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<div class="section" id="tutorial-http-2-server">
<h1>Tutorial: HTTP/2 server<a class="headerlink" href="#tutorial-http-2-server" title="Permalink to this headline"></a></h1>
<p>In this tutorial, we are going to write single-threaded, event-based
HTTP/2 web server, which supports HTTPS only. It can handle
concurrent multiple requests, but only GET method is supported. The
complete source code, <a class="reference internal" href="#libevent-server-c">libevent-server.c</a>, is attached at the end of
this page. It also resides in examples directory in the archive or
repository.</p>
<p>This simple server takes 3 arguments, a port number to listen to, a
path to SSL/TLS private key file and certificate file. Its synopsis
is like this:</p>
<div class="highlight-c"><div class="highlight"><pre>$ libevent-server PORT /path/to/server.key /path/to/server.crt
</pre></div>
</div>
<p>We use libevent in this tutorial to handle networking I/O. Please
note that nghttp2 itself does not depend on libevent.</p>
<p>First we do some setup routine for libevent and OpenSSL library in
function <tt class="docutils literal"><span class="pre">main()</span></tt> and <tt class="docutils literal"><span class="pre">run()</span></tt>, which is not so relevant to nghttp2
library use. The one thing you should look at is setup NPN callback.
The NPN callback is used for the server to advertise the application
protocols the server supports to a client. In this example program,
when creating <tt class="docutils literal"><span class="pre">SSL_CTX</span></tt> object, we stores the application protocol
name in the wire format of NPN in statically allocated buffer. This is
safe because we only create 1 <tt class="docutils literal"><span class="pre">SSL_CTX</span></tt> object in the entire program
life time:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">unsigned</span> <span class="kt">char</span> <span class="n">next_proto_list</span><span class="p">[</span><span class="mi">256</span><span class="p">];</span>
<span class="k">static</span> <span class="kt">size_t</span> <span class="n">next_proto_list_len</span><span class="p">;</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">next_proto_cb</span><span class="p">(</span><span class="n">SSL</span> <span class="o">*</span><span class="n">s</span><span class="p">,</span> <span class="k">const</span> <span class="kt">unsigned</span> <span class="kt">char</span> <span class="o">**</span><span class="n">data</span><span class="p">,</span> <span class="kt">unsigned</span> <span class="kt">int</span> <span class="o">*</span><span class="n">len</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">arg</span><span class="p">)</span>
<span class="p">{</span>
<span class="o">*</span><span class="n">data</span> <span class="o">=</span> <span class="n">next_proto_list</span><span class="p">;</span>
<span class="o">*</span><span class="n">len</span> <span class="o">=</span> <span class="n">next_proto_list_len</span><span class="p">;</span>
<span class="k">return</span> <span class="n">SSL_TLSEXT_ERR_OK</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="n">SSL_CTX</span><span class="o">*</span> <span class="nf">create_ssl_ctx</span><span class="p">(</span><span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">key_file</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">cert_file</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">;</span>
<span class="n">ssl_ctx</span> <span class="o">=</span> <span class="n">SSL_CTX_new</span><span class="p">(</span><span class="n">SSLv23_server_method</span><span class="p">());</span>
<span class="p">...</span>
<span class="n">next_proto_list</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">=</span> <span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">;</span>
<span class="n">memcpy</span><span class="p">(</span><span class="o">&amp;</span><span class="n">next_proto_list</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">NGHTTP2_PROTO_VERSION_ID</span><span class="p">,</span>
<span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">);</span>
<span class="n">next_proto_list_len</span> <span class="o">=</span> <span class="mi">1</span> <span class="o">+</span> <span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">;</span>
<span class="n">SSL_CTX_set_next_protos_advertised_cb</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">,</span> <span class="n">next_proto_cb</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="k">return</span> <span class="n">ssl_ctx</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The wire format of NPN is a sequence of length prefixed string. The
exactly one byte is used to specify the length of each protocol
identifier. In this tutorial, we advertise the HTTP/2 protocol the
nghttp2 library supports. The nghttp2 library exports its identifier
in <a class="reference internal" href="apiref.html#c.NGHTTP2_PROTO_VERSION_ID" title="NGHTTP2_PROTO_VERSION_ID"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_PROTO_VERSION_ID</span></tt></a>. The <tt class="docutils literal"><span class="pre">next_proto_cb()</span></tt> function
is the server-side NPN callback. In OpenSSL implementation, we just
assign the pointer to the NPN buffers we filled earlier. The NPN
callback function is set to <tt class="docutils literal"><span class="pre">SSL_CTX</span></tt> object using
<tt class="docutils literal"><span class="pre">SSL_CTX_set_next_protos_advertised_cb()</span></tt>.</p>
<p>We use <tt class="docutils literal"><span class="pre">app_content</span></tt> structure to store the application-wide data:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">struct</span> <span class="n">app_context</span> <span class="p">{</span>
<span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">;</span>
<span class="p">};</span>
</pre></div>
</div>
<p>We use <tt class="docutils literal"><span class="pre">http2_session_data</span></tt> structure to store the session-level
(which corresponds to 1 HTTP/2 connection) data:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">typedef</span> <span class="k">struct</span> <span class="n">http2_session_data</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="n">root</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">;</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">;</span>
<span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">;</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">client_addr</span><span class="p">;</span>
<span class="kt">size_t</span> <span class="n">handshake_leftlen</span><span class="p">;</span>
<span class="p">}</span> <span class="n">http2_session_data</span><span class="p">;</span>
</pre></div>
</div>
<p>We use <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> structure to store the stream-level
data:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">typedef</span> <span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">prev</span><span class="p">,</span> <span class="o">*</span><span class="n">next</span><span class="p">;</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">request_path</span><span class="p">;</span>
<span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">;</span>
<span class="kt">int</span> <span class="n">fd</span><span class="p">;</span>
<span class="p">}</span> <span class="n">http2_stream_data</span><span class="p">;</span>
</pre></div>
</div>
<p>1 HTTP/2 session can have multiple streams. We manage these multiple
streams by intrusive doubly linked list to add and remove the object
in O(1). The first element of this list is pointed by the
<tt class="docutils literal"><span class="pre">root-&gt;next</span></tt> in <tt class="docutils literal"><span class="pre">http2_session_data</span></tt>. Initially, <tt class="docutils literal"><span class="pre">root-&gt;next</span></tt>
is <tt class="docutils literal"><span class="pre">NULL</span></tt>. The <tt class="docutils literal"><span class="pre">handshake_leftlen</span></tt> member of
<tt class="docutils literal"><span class="pre">http2_session_data</span></tt> is used to track the number of bytes remaining
when receiving first client connection preface
(<a class="reference internal" href="apiref.html#c.NGHTTP2_CLIENT_CONNECTION_PREFACE" title="NGHTTP2_CLIENT_CONNECTION_PREFACE"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_CLIENT_CONNECTION_PREFACE</span></tt></a>), which is 24 bytes magic
byte string, from the client. We use libevent&#8217;s bufferevent structure
to perform network I/O. Notice that bufferevent object is in
<tt class="docutils literal"><span class="pre">http2_session_data</span></tt> and not in <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt>. This is
because <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> is just a logical stream multiplexed
over the single connection managed by bufferevent in
<tt class="docutils literal"><span class="pre">http2_session_data</span></tt>.</p>
<p>We first create listener object to accept incoming connections.
We use libevent&#8217;s <tt class="docutils literal"><span class="pre">struct</span> <span class="pre">evconnlistener</span></tt> for this purpose:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">start_listen</span><span class="p">(</span><span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">service</span><span class="p">,</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">addrinfo</span> <span class="n">hints</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">addrinfo</span> <span class="o">*</span><span class="n">res</span><span class="p">,</span> <span class="o">*</span><span class="n">rp</span><span class="p">;</span>
<span class="n">memset</span><span class="p">(</span><span class="o">&amp;</span><span class="n">hints</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">hints</span><span class="p">));</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_family</span> <span class="o">=</span> <span class="n">AF_UNSPEC</span><span class="p">;</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_socktype</span> <span class="o">=</span> <span class="n">SOCK_STREAM</span><span class="p">;</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_flags</span> <span class="o">=</span> <span class="n">AI_PASSIVE</span><span class="p">;</span>
<span class="cp">#ifdef AI_ADDRCONFIG</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_flags</span> <span class="o">|=</span> <span class="n">AI_ADDRCONFIG</span><span class="p">;</span>
<span class="cp">#endif </span><span class="c1">// AI_ADDRCONFIG</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">getaddrinfo</span><span class="p">(</span><span class="nb">NULL</span><span class="p">,</span> <span class="n">service</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">hints</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">res</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">for</span><span class="p">(</span><span class="n">rp</span> <span class="o">=</span> <span class="n">res</span><span class="p">;</span> <span class="n">rp</span><span class="p">;</span> <span class="n">rp</span> <span class="o">=</span> <span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_next</span><span class="p">)</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">evconnlistener</span> <span class="o">*</span><span class="n">listener</span><span class="p">;</span>
<span class="n">listener</span> <span class="o">=</span> <span class="n">evconnlistener_new_bind</span><span class="p">(</span><span class="n">evbase</span><span class="p">,</span> <span class="n">acceptcb</span><span class="p">,</span> <span class="n">app_ctx</span><span class="p">,</span>
<span class="n">LEV_OPT_CLOSE_ON_FREE</span> <span class="o">|</span>
<span class="n">LEV_OPT_REUSEABLE</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">,</span>
<span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_addr</span><span class="p">,</span> <span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_addrlen</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">listener</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not start listener&quot;</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We specify <tt class="docutils literal"><span class="pre">acceptcb</span></tt> callback which is called when a new connection
is accepted:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">acceptcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">evconnlistener</span> <span class="o">*</span><span class="n">listener</span><span class="p">,</span> <span class="kt">int</span> <span class="n">fd</span><span class="p">,</span>
<span class="k">struct</span> <span class="n">sockaddr</span> <span class="o">*</span><span class="n">addr</span><span class="p">,</span> <span class="kt">int</span> <span class="n">addrlen</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">arg</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span> <span class="o">=</span> <span class="p">(</span><span class="n">app_context</span><span class="o">*</span><span class="p">)</span><span class="n">arg</span><span class="p">;</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">;</span>
<span class="n">session_data</span> <span class="o">=</span> <span class="n">create_http2_session_data</span><span class="p">(</span><span class="n">app_ctx</span><span class="p">,</span> <span class="n">fd</span><span class="p">,</span> <span class="n">addr</span><span class="p">,</span> <span class="n">addrlen</span><span class="p">);</span>
<span class="n">bufferevent_setcb</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">,</span> <span class="n">handshake_readcb</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">,</span> <span class="n">eventcb</span><span class="p">,</span>
<span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Here we create <tt class="docutils literal"><span class="pre">http2_session_data</span></tt> object. The bufferevent for this
connection is also initialized at this time. We specify 2 callbacks
for the bufferevent: <tt class="docutils literal"><span class="pre">handshake_readcb</span></tt> and <tt class="docutils literal"><span class="pre">eventcb</span></tt>.</p>
<p>The <tt class="docutils literal"><span class="pre">eventcb()</span></tt> is invoked by libevent event loop when an event
(e.g., connection has been established, timeout, etc) happens on the
underlying network socket:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">eventcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">short</span> <span class="n">events</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_CONNECTED</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s connected</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_EOF</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s EOF</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_ERROR</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s network error</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_TIMEOUT</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s timeout</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
</div>
<p>For <tt class="docutils literal"><span class="pre">BEV_EVENT_EOF</span></tt>, <tt class="docutils literal"><span class="pre">BEV_EVENT_ERROR</span></tt> and <tt class="docutils literal"><span class="pre">BEV_EVENT_TIMEOUT</span></tt>
event, we just simply tear down the connection. The
<tt class="docutils literal"><span class="pre">delete_http2_session_data()</span></tt> function destroys
<tt class="docutils literal"><span class="pre">http2_session_data</span></tt> object and thus its bufferevent member. As a
result, the underlying connection is closed. The
<tt class="docutils literal"><span class="pre">BEV_EVENT_CONNECTED</span></tt> event is invoked when SSL/TLS handshake is
finished successfully.</p>
<p>The <tt class="docutils literal"><span class="pre">handshake_readcb()</span></tt> is a callback function to handle 24 bytes
magic byte string from a client, since nghttp2 library does not handle
it:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">handshake_readcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="kt">uint8_t</span> <span class="n">data</span><span class="p">[</span><span class="mi">24</span><span class="p">];</span>
<span class="k">struct</span> <span class="n">evbuffer</span> <span class="o">*</span><span class="n">input</span> <span class="o">=</span> <span class="n">bufferevent_get_input</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="kt">int</span> <span class="n">readlen</span> <span class="o">=</span> <span class="n">evbuffer_remove</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span><span class="p">);</span>
<span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">conhead</span> <span class="o">=</span> <span class="n">NGHTTP2_CLIENT_CONNECTION_PREFACE</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">memcmp</span><span class="p">(</span><span class="n">conhead</span> <span class="o">+</span> <span class="n">NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN</span>
<span class="o">-</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">readlen</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span> <span class="o">-=</span> <span class="n">readlen</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">bufferevent_setcb</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">,</span> <span class="n">readcb</span><span class="p">,</span> <span class="n">writecb</span><span class="p">,</span> <span class="n">eventcb</span><span class="p">,</span> <span class="n">ptr</span><span class="p">);</span>
<span class="cm">/* Process pending data in buffer since they are not notified</span>
<span class="cm"> further */</span>
<span class="n">initialize_nghttp2_session</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">send_server_connection_header</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_recv</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We check that the received byte string matches
<a class="reference internal" href="apiref.html#c.NGHTTP2_CLIENT_CONNECTION_PREFACE" title="NGHTTP2_CLIENT_CONNECTION_PREFACE"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_CLIENT_CONNECTION_PREFACE</span></tt></a>. When they match, the
connection state is ready for starting HTTP/2 communication. First
we change the callback functions for the bufferevent object. We use
same <tt class="docutils literal"><span class="pre">eventcb</span></tt> as before. But we specify new <tt class="docutils literal"><span class="pre">readcb</span></tt> and
<tt class="docutils literal"><span class="pre">writecb</span></tt> function to handle HTTP/2 communication. We describe
these 2 functions later.</p>
<p>We initialize nghttp2 session object which is done in
<tt class="docutils literal"><span class="pre">initialize_nghttp2_session()</span></tt>:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">initialize_nghttp2_session</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">nghttp2_session_callbacks</span> <span class="n">callbacks</span> <span class="o">=</span> <span class="p">{</span><span class="mi">0</span><span class="p">};</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">send_callback</span> <span class="o">=</span> <span class="n">send_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_frame_recv_callback</span> <span class="o">=</span> <span class="n">on_frame_recv_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_stream_close_callback</span> <span class="o">=</span> <span class="n">on_stream_close_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_header_callback</span> <span class="o">=</span> <span class="n">on_header_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_begin_headers_callback</span> <span class="o">=</span> <span class="n">on_begin_headers_callback</span><span class="p">;</span>
<span class="n">nghttp2_session_server_new</span><span class="p">(</span><span class="o">&amp;</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">callbacks</span><span class="p">,</span> <span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Since we are creating server, nghttp2 session object is created using
<a class="reference internal" href="apiref.html#c.nghttp2_session_server_new" title="nghttp2_session_server_new"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_server_new()</span></tt></a> function. We registers 5 callbacks to
nghttp2 session object. We&#8217;ll talk about these callbacks later.</p>
<p>After initialization of nghttp2 session object, we are going to send
server connection header in <tt class="docutils literal"><span class="pre">send_server_connection_header()</span></tt>:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">send_server_connection_header</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">nghttp2_settings_entry</span> <span class="n">iv</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span> <span class="o">=</span> <span class="p">{</span>
<span class="p">{</span> <span class="n">NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS</span><span class="p">,</span> <span class="mi">100</span> <span class="p">}</span>
<span class="p">};</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_submit_settings</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="n">NGHTTP2_FLAG_NONE</span><span class="p">,</span>
<span class="n">iv</span><span class="p">,</span> <span class="n">ARRLEN</span><span class="p">(</span><span class="n">iv</span><span class="p">));</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The server connection header is SETTINGS frame. We specify
SETTINGS_MAX_CONCURRENT_STREAMS to 100 in SETTINGS frame. To queue
the SETTINGS frame for the transmission, we use
<a class="reference internal" href="apiref.html#c.nghttp2_submit_settings" title="nghttp2_submit_settings"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_submit_settings()</span></tt></a>. Note that <a class="reference internal" href="apiref.html#c.nghttp2_submit_settings" title="nghttp2_submit_settings"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_submit_settings()</span></tt></a>
function only queues the frame and not actually send it. All
<tt class="docutils literal"><span class="pre">nghttp2_submit_*()</span></tt> family functions have this property. To
actually send the frame, <a class="reference internal" href="apiref.html#c.nghttp2_session_send" title="nghttp2_session_send"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_send()</span></tt></a> is used, which is
described about later.</p>
<p>Since bufferevent may buffer more than first 24 bytes from the client,
we have to process them here since libevent won&#8217;t invoke callback
functions for these pending data. To process received data, we call
<tt class="docutils literal"><span class="pre">session_recv()</span></tt> function:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">session_recv</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">evbuffer</span> <span class="o">*</span><span class="n">input</span> <span class="o">=</span> <span class="n">bufferevent_get_input</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="kt">size_t</span> <span class="n">datalen</span> <span class="o">=</span> <span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">input</span><span class="p">);</span>
<span class="kt">unsigned</span> <span class="kt">char</span> <span class="o">*</span><span class="n">data</span> <span class="o">=</span> <span class="n">evbuffer_pullup</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">);</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_session_mem_recv</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">datalen</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">&lt;</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">evbuffer_drain</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="n">rv</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_send</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>In this function, we feed all unprocessed, received data to nghttp2
session object using <a class="reference internal" href="apiref.html#c.nghttp2_session_mem_recv" title="nghttp2_session_mem_recv"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_mem_recv()</span></tt></a> function. The
<a class="reference internal" href="apiref.html#c.nghttp2_session_mem_recv" title="nghttp2_session_mem_recv"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_mem_recv()</span></tt></a> processes the received data and may
invoke nghttp2 callbacks and also queue outgoing frames. Since there
may be pending frames, we call <tt class="docutils literal"><span class="pre">session_send()</span></tt> function to send
those frames. The <tt class="docutils literal"><span class="pre">session_send()</span></tt> function is defined as follows:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">session_send</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_session_send</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The <a class="reference internal" href="apiref.html#c.nghttp2_session_send" title="nghttp2_session_send"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_send()</span></tt></a> function serializes the frame into wire
format and call <a class="reference internal" href="apiref.html#c.nghttp2_session_callbacks.send_callback" title="nghttp2_session_callbacks.send_callback"><tt class="xref c c-member docutils literal"><span class="pre">nghttp2_session_callbacks.send_callback</span></tt></a> with
it. We set <tt class="docutils literal"><span class="pre">send_callback()</span></tt> function to
<a class="reference internal" href="apiref.html#c.nghttp2_session_callbacks.send_callback" title="nghttp2_session_callbacks.send_callback"><tt class="xref c c-member docutils literal"><span class="pre">nghttp2_session_callbacks.send_callback</span></tt></a> in
<tt class="docutils literal"><span class="pre">initialize_nghttp2_session()</span></tt> function described earlier. It is
defined as follows:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">ssize_t</span> <span class="nf">send_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">data</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">length</span><span class="p">,</span>
<span class="kt">int</span> <span class="n">flags</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span> <span class="o">=</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">;</span>
<span class="cm">/* Avoid excessive buffering in server side. */</span>
<span class="k">if</span><span class="p">(</span><span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">bufferevent_get_output</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">))</span> <span class="o">&gt;=</span>
<span class="n">OUTPUT_WOULDBLOCK_THRESHOLD</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_WOULDBLOCK</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">bufferevent_write</span><span class="p">(</span><span class="n">bev</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">length</span><span class="p">);</span>
<span class="k">return</span> <span class="n">length</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Since we use bufferevent to abstract network I/O, we just write the
data to the bufferevent object. Note that <a class="reference internal" href="apiref.html#c.nghttp2_session_send" title="nghttp2_session_send"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_send()</span></tt></a>
continues to write all frames queued so far. If we were writing the
data to the non-blocking socket directly using <tt class="docutils literal"><span class="pre">write()</span></tt> system call
in the <a class="reference internal" href="apiref.html#c.nghttp2_session_callbacks.send_callback" title="nghttp2_session_callbacks.send_callback"><tt class="xref c c-member docutils literal"><span class="pre">nghttp2_session_callbacks.send_callback</span></tt></a>, we will
surely get <tt class="docutils literal"><span class="pre">EAGAIN</span></tt> or <tt class="docutils literal"><span class="pre">EWOULDBLOCK</span></tt> since the socket has limited
send buffer. If that happens, we can return
<a class="reference internal" href="apiref.html#c.NGHTTP2_ERR_WOULDBLOCK" title="NGHTTP2_ERR_WOULDBLOCK"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_ERR_WOULDBLOCK</span></tt></a> to signal the nghttp2 library to stop
sending further data. But writing to the bufferevent, we have to
regulate the amount data to be buffered by ourselves to avoid possible
huge memory consumption. To achieve this, we check the size of output
buffer and if it is more than or equal to
<tt class="docutils literal"><span class="pre">OUTPUT_WOULDBLOCK_THRESHOLD</span></tt> bytes, we stop writing data and return
<a class="reference internal" href="apiref.html#c.NGHTTP2_ERR_WOULDBLOCK" title="NGHTTP2_ERR_WOULDBLOCK"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_ERR_WOULDBLOCK</span></tt></a> to tell the library to stop calling
send_callback.</p>
<p>The next bufferevent callback is <tt class="docutils literal"><span class="pre">readcb()</span></tt>, which is invoked when
data is available to read in the bufferevent input buffer:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">readcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_recv</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
<p>In this function, we just call <tt class="docutils literal"><span class="pre">session_recv()</span></tt> to process incoming
data.</p>
<p>The third bufferevent callback is <tt class="docutils literal"><span class="pre">writecb()</span></tt>, which is invoked when
all data written in the bufferevent output buffer have been sent:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">void</span> <span class="nf">writecb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">bufferevent_get_output</span><span class="p">(</span><span class="n">bev</span><span class="p">))</span> <span class="o">&gt;</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">nghttp2_session_want_read</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span> <span class="o">&amp;&amp;</span>
<span class="n">nghttp2_session_want_write</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_send</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
<p>First we check whether we should drop connection or not. The nghttp2
session object keeps track of reception and transmission of GOAWAY
frame and other error conditions as well. Using these information,
nghttp2 session object will tell whether the connection should be
dropped or not. More specifically, both <a class="reference internal" href="apiref.html#c.nghttp2_session_want_read" title="nghttp2_session_want_read"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_want_read()</span></tt></a>
and <a class="reference internal" href="apiref.html#c.nghttp2_session_want_write" title="nghttp2_session_want_write"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_want_write()</span></tt></a> return 0, we have no business in
the connection. But since we are using bufferevent and its deferred
callback option, the bufferevent output buffer may contain the pending
data when the <tt class="docutils literal"><span class="pre">writecb()</span></tt> is called. To handle this situation, we
also check whether the output buffer is empty or not. If these
conditions are met, we drop connection.</p>
<p>Otherwise, we call <tt class="docutils literal"><span class="pre">session_send()</span></tt> to process pending output
data. Remember that in <tt class="docutils literal"><span class="pre">send_callback()</span></tt>, we may not write all data
to bufferevent to avoid excessive buffering. We continue process
pending data when output buffer becomes empty.</p>
<p>We have already described about nghttp2 callback <tt class="docutils literal"><span class="pre">send_callback()</span></tt>.
Let&#8217;s describe remaining nghttp2 callbacks we setup in
<tt class="docutils literal"><span class="pre">initialize_nghttp2_setup()</span></tt> function.</p>
<p>The <tt class="docutils literal"><span class="pre">on_begin_headers_callback()</span></tt> function is invoked when reception
of header block in HEADERS or PUSH_PROMISE frame is started:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">on_begin_headers_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span> <span class="o">!=</span> <span class="n">NGHTTP2_HEADERS</span> <span class="o">||</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">headers</span><span class="p">.</span><span class="n">cat</span> <span class="o">!=</span> <span class="n">NGHTTP2_HCAT_REQUEST</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">create_http2_stream_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="n">nghttp2_session_set_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">,</span>
<span class="n">stream_data</span><span class="p">);</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We only interested in HEADERS frame in this function. Since HEADERS
frame has several roles in HTTP/2 protocol, we check that it is a
request HEADERS, which opens new stream. If frame is request HEADERS,
then we create <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> object to store stream related
data. We associate created <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> object to the stream
in nghttp2 session object using <tt class="xref c c-func docutils literal"><span class="pre">nghttp2_set_stream_user_data()</span></tt> in
order to get the object without searching through doubly linked list.</p>
<p>In this example server, we want to serve files relative to the current
working directory the program was invoked. Each header name/value pair
is emitted via <tt class="docutils literal"><span class="pre">on_header_callback</span></tt> function, which is called after
<tt class="docutils literal"><span class="pre">on_begin_headers_callback()</span></tt>:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">on_header_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">name</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">namelen</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">value</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">valuelen</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">const</span> <span class="kt">char</span> <span class="n">PATH</span><span class="p">[]</span> <span class="o">=</span> <span class="s">&quot;:path&quot;</span><span class="p">;</span>
<span class="k">switch</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span><span class="p">)</span> <span class="p">{</span>
<span class="k">case</span> <span class="n">NGHTTP2_HEADERS</span>:
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">headers</span><span class="p">.</span><span class="n">cat</span> <span class="o">!=</span> <span class="n">NGHTTP2_HCAT_REQUEST</span><span class="p">)</span> <span class="p">{</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span> <span class="o">||</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">)</span> <span class="p">{</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">namelen</span> <span class="o">==</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">PATH</span><span class="p">)</span> <span class="o">-</span> <span class="mi">1</span> <span class="o">&amp;&amp;</span> <span class="n">memcmp</span><span class="p">(</span><span class="n">PATH</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">namelen</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="kt">size_t</span> <span class="n">j</span><span class="p">;</span>
<span class="k">for</span><span class="p">(</span><span class="n">j</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="n">j</span> <span class="o">&lt;</span> <span class="n">valuelen</span> <span class="o">&amp;&amp;</span> <span class="n">value</span><span class="p">[</span><span class="n">j</span><span class="p">]</span> <span class="o">!=</span> <span class="sc">&#39;?&#39;</span><span class="p">;</span> <span class="o">++</span><span class="n">j</span><span class="p">);</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span> <span class="o">=</span> <span class="n">percent_decode</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">j</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We search <tt class="docutils literal"><span class="pre">:path</span></tt> header field in request headers and keep the
requested path in <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> object. In this example
program, we ignore <tt class="docutils literal"><span class="pre">:method</span></tt> header field and always treat the
request as GET request.</p>
<p>The <tt class="docutils literal"><span class="pre">on_frame_recv_callback()</span></tt> function is invoked when a frame is
fully received:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">on_frame_recv_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">switch</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span><span class="p">)</span> <span class="p">{</span>
<span class="k">case</span> <span class="n">NGHTTP2_DATA</span>:
<span class="k">case</span> <span class="n">NGHTTP2_HEADERS</span>:
<span class="cm">/* Check that the client request has finished */</span>
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">flags</span> <span class="o">&amp;</span> <span class="n">NGHTTP2_FLAG_END_STREAM</span><span class="p">)</span> <span class="p">{</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="cm">/* For DATA and HEADERS frame, this callback may be called after</span>
<span class="cm"> on_stream_close_callback. Check that stream still alive. */</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">on_request_recv</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">session_data</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">break</span><span class="p">;</span>
<span class="nl">default:</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>First we retrieve <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> object associated to the
stream in <tt class="docutils literal"><span class="pre">on_begin_headers_callback()</span></tt>. It is done using
<a class="reference internal" href="apiref.html#c.nghttp2_session_get_stream_user_data" title="nghttp2_session_get_stream_user_data"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_session_get_stream_user_data()</span></tt></a>. If the requested path cannot
be served for some reasons (e.g., file is not found), we send 404
response, which is done in <tt class="docutils literal"><span class="pre">error_reply()</span></tt>. Otherwise, we open
requested file and send its content. We send 1 header field
<tt class="docutils literal"><span class="pre">:status</span></tt> as a response header.</p>
<p>Sending content of a file is done in <tt class="docutils literal"><span class="pre">send_response()</span></tt> function:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">send_response</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span> <span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="n">nghttp2_nv</span> <span class="o">*</span><span class="n">nva</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">nvlen</span><span class="p">,</span> <span class="kt">int</span> <span class="n">fd</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">nghttp2_data_provider</span> <span class="n">data_prd</span><span class="p">;</span>
<span class="n">data_prd</span><span class="p">.</span><span class="n">source</span><span class="p">.</span><span class="n">fd</span> <span class="o">=</span> <span class="n">fd</span><span class="p">;</span>
<span class="n">data_prd</span><span class="p">.</span><span class="n">read_callback</span> <span class="o">=</span> <span class="n">file_read_callback</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_submit_response</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_id</span><span class="p">,</span> <span class="n">nva</span><span class="p">,</span> <span class="n">nvlen</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">data_prd</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The nghttp2 library uses <a class="reference internal" href="apiref.html#c.nghttp2_data_provider" title="nghttp2_data_provider"><tt class="xref c c-type docutils literal"><span class="pre">nghttp2_data_provider</span></tt></a> structure to
send entity body to the remote peer. The <tt class="docutils literal"><span class="pre">source</span></tt> member of this
structure is a union and it can be either void pointer or int which is
intended to be used as file descriptor. In this example server, we use
file descriptor. We also set <tt class="docutils literal"><span class="pre">file_read_callback()</span></tt> callback
function to read content of the file:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">ssize_t</span> <span class="nf">file_read_callback</span>
<span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span> <span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="kt">uint8_t</span> <span class="o">*</span><span class="n">buf</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">length</span><span class="p">,</span> <span class="kt">uint32_t</span> <span class="o">*</span><span class="n">data_flags</span><span class="p">,</span>
<span class="n">nghttp2_data_source</span> <span class="o">*</span><span class="n">source</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">fd</span> <span class="o">=</span> <span class="n">source</span><span class="o">-&gt;</span><span class="n">fd</span><span class="p">;</span>
<span class="kt">ssize_t</span> <span class="n">r</span><span class="p">;</span>
<span class="k">while</span><span class="p">((</span><span class="n">r</span> <span class="o">=</span> <span class="n">read</span><span class="p">(</span><span class="n">fd</span><span class="p">,</span> <span class="n">buf</span><span class="p">,</span> <span class="n">length</span><span class="p">))</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span> <span class="o">&amp;&amp;</span> <span class="n">errno</span> <span class="o">==</span> <span class="n">EINTR</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">r</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">r</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="o">*</span><span class="n">data_flags</span> <span class="o">|=</span> <span class="n">NGHTTP2_DATA_FLAG_EOF</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">r</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>If error happens while reading file, we return
<a class="reference internal" href="apiref.html#c.NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE" title="NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE</span></tt></a>. This tells the
library to send RST_STREAM to the stream. When all data are read, set
<a class="reference internal" href="apiref.html#c.NGHTTP2_DATA_FLAG_EOF" title="NGHTTP2_DATA_FLAG_EOF"><tt class="xref c c-macro docutils literal"><span class="pre">NGHTTP2_DATA_FLAG_EOF</span></tt></a> flag to <tt class="docutils literal"><span class="pre">*data_flags</span></tt> to tell the
nghttp2 library that we have finished reading file.</p>
<p>The <a class="reference internal" href="apiref.html#c.nghttp2_submit_response" title="nghttp2_submit_response"><tt class="xref c c-func docutils literal"><span class="pre">nghttp2_submit_response()</span></tt></a> is used to send response to the remote
peer.</p>
<p>The <tt class="docutils literal"><span class="pre">on_stream_close_callback()</span></tt> function is invoked when the stream
is about to close:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="kt">int</span> <span class="nf">on_stream_close_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="n">nghttp2_error_code</span> <span class="n">error_code</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_id</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">remove_stream</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">);</span>
<span class="n">delete_http2_stream_data</span><span class="p">(</span><span class="n">stream_data</span><span class="p">);</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We destroy <tt class="docutils literal"><span class="pre">http2_stream_data</span></tt> object in this function since the
stream is about to close and we no longer use that object.</p>
<div class="section" id="libevent-server-c">
<h2>libevent-server.c<a class="headerlink" href="#libevent-server-c" title="Permalink to this headline"></a></h2>
<div class="highlight-c"><div class="highlight"><pre><span class="cm">/*</span>
<span class="cm"> * nghttp2 - HTTP/2 C Library</span>
<span class="cm"> *</span>
<span class="cm"> * Copyright (c) 2013 Tatsuhiro Tsujikawa</span>
<span class="cm"> *</span>
<span class="cm"> * Permission is hereby granted, free of charge, to any person obtaining</span>
<span class="cm"> * a copy of this software and associated documentation files (the</span>
<span class="cm"> * &quot;Software&quot;), to deal in the Software without restriction, including</span>
<span class="cm"> * without limitation the rights to use, copy, modify, merge, publish,</span>
<span class="cm"> * distribute, sublicense, and/or sell copies of the Software, and to</span>
<span class="cm"> * permit persons to whom the Software is furnished to do so, subject to</span>
<span class="cm"> * the following conditions:</span>
<span class="cm"> *</span>
<span class="cm"> * The above copyright notice and this permission notice shall be</span>
<span class="cm"> * included in all copies or substantial portions of the Software.</span>
<span class="cm"> *</span>
<span class="cm"> * THE SOFTWARE IS PROVIDED &quot;AS IS&quot;, WITHOUT WARRANTY OF ANY KIND,</span>
<span class="cm"> * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF</span>
<span class="cm"> * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND</span>
<span class="cm"> * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE</span>
<span class="cm"> * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION</span>
<span class="cm"> * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION</span>
<span class="cm"> * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.</span>
<span class="cm"> */</span>
<span class="cp">#include &lt;sys/types.h&gt;</span>
<span class="cp">#include &lt;sys/socket.h&gt;</span>
<span class="cp">#include &lt;netdb.h&gt;</span>
<span class="cp">#include &lt;signal.h&gt;</span>
<span class="cp">#include &lt;unistd.h&gt;</span>
<span class="cp">#include &lt;sys/stat.h&gt;</span>
<span class="cp">#include &lt;fcntl.h&gt;</span>
<span class="cp">#include &lt;ctype.h&gt;</span>
<span class="cp">#include &lt;netinet/in.h&gt;</span>
<span class="cp">#include &lt;netinet/tcp.h&gt;</span>
<span class="cp">#include &lt;err.h&gt;</span>
<span class="cp">#include &lt;openssl/ssl.h&gt;</span>
<span class="cp">#include &lt;openssl/err.h&gt;</span>
<span class="cp">#include &lt;event.h&gt;</span>
<span class="cp">#include &lt;event2/event.h&gt;</span>
<span class="cp">#include &lt;event2/bufferevent_ssl.h&gt;</span>
<span class="cp">#include &lt;event2/listener.h&gt;</span>
<span class="cp">#include &lt;nghttp2/nghttp2.h&gt;</span>
<span class="cp">#define OUTPUT_WOULDBLOCK_THRESHOLD (1 &lt;&lt; 16)</span>
<span class="cp">#define ARRLEN(x) (sizeof(x)/sizeof(x[0]))</span>
<span class="cp">#define MAKE_NV(NAME, VALUE) \</span>
<span class="cp"> { (uint8_t*)NAME, (uint8_t*)VALUE, sizeof(NAME) - 1, sizeof(VALUE) - 1, \</span>
<span class="cp"> NGHTTP2_NV_FLAG_NONE }</span>
<span class="k">struct</span> <span class="n">app_context</span><span class="p">;</span>
<span class="k">typedef</span> <span class="k">struct</span> <span class="n">app_context</span> <span class="n">app_context</span><span class="p">;</span>
<span class="k">typedef</span> <span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">prev</span><span class="p">,</span> <span class="o">*</span><span class="n">next</span><span class="p">;</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">request_path</span><span class="p">;</span>
<span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">;</span>
<span class="kt">int</span> <span class="n">fd</span><span class="p">;</span>
<span class="p">}</span> <span class="n">http2_stream_data</span><span class="p">;</span>
<span class="k">typedef</span> <span class="k">struct</span> <span class="n">http2_session_data</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">http2_stream_data</span> <span class="n">root</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">;</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">;</span>
<span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">;</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">client_addr</span><span class="p">;</span>
<span class="kt">size_t</span> <span class="n">handshake_leftlen</span><span class="p">;</span>
<span class="p">}</span> <span class="n">http2_session_data</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">app_context</span> <span class="p">{</span>
<span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">;</span>
<span class="p">};</span>
<span class="k">static</span> <span class="kt">unsigned</span> <span class="kt">char</span> <span class="n">next_proto_list</span><span class="p">[</span><span class="mi">256</span><span class="p">];</span>
<span class="k">static</span> <span class="kt">size_t</span> <span class="n">next_proto_list_len</span><span class="p">;</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">next_proto_cb</span><span class="p">(</span><span class="n">SSL</span> <span class="o">*</span><span class="n">s</span><span class="p">,</span> <span class="k">const</span> <span class="kt">unsigned</span> <span class="kt">char</span> <span class="o">**</span><span class="n">data</span><span class="p">,</span> <span class="kt">unsigned</span> <span class="kt">int</span> <span class="o">*</span><span class="n">len</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">arg</span><span class="p">)</span>
<span class="p">{</span>
<span class="o">*</span><span class="n">data</span> <span class="o">=</span> <span class="n">next_proto_list</span><span class="p">;</span>
<span class="o">*</span><span class="n">len</span> <span class="o">=</span> <span class="n">next_proto_list_len</span><span class="p">;</span>
<span class="k">return</span> <span class="n">SSL_TLSEXT_ERR_OK</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Create SSL_CTX. */</span>
<span class="k">static</span> <span class="n">SSL_CTX</span><span class="o">*</span> <span class="nf">create_ssl_ctx</span><span class="p">(</span><span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">key_file</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">cert_file</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">;</span>
<span class="n">ssl_ctx</span> <span class="o">=</span> <span class="n">SSL_CTX_new</span><span class="p">(</span><span class="n">SSLv23_server_method</span><span class="p">());</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">ssl_ctx</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not create SSL/TLS context: %s&quot;</span><span class="p">,</span>
<span class="n">ERR_error_string</span><span class="p">(</span><span class="n">ERR_get_error</span><span class="p">(),</span> <span class="nb">NULL</span><span class="p">));</span>
<span class="p">}</span>
<span class="n">SSL_CTX_set_options</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">,</span>
<span class="n">SSL_OP_ALL</span> <span class="o">|</span> <span class="n">SSL_OP_NO_SSLv2</span> <span class="o">|</span> <span class="n">SSL_OP_NO_COMPRESSION</span> <span class="o">|</span>
<span class="n">SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">SSL_CTX_use_PrivateKey_file</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">,</span> <span class="n">key_file</span><span class="p">,</span>
<span class="n">SSL_FILETYPE_PEM</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not read private key file %s&quot;</span><span class="p">,</span> <span class="n">key_file</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">SSL_CTX_use_certificate_chain_file</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">,</span> <span class="n">cert_file</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not read certificate file %s&quot;</span><span class="p">,</span> <span class="n">cert_file</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">next_proto_list</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">=</span> <span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">;</span>
<span class="n">memcpy</span><span class="p">(</span><span class="o">&amp;</span><span class="n">next_proto_list</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">NGHTTP2_PROTO_VERSION_ID</span><span class="p">,</span>
<span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">);</span>
<span class="n">next_proto_list_len</span> <span class="o">=</span> <span class="mi">1</span> <span class="o">+</span> <span class="n">NGHTTP2_PROTO_VERSION_ID_LEN</span><span class="p">;</span>
<span class="n">SSL_CTX_set_next_protos_advertised_cb</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">,</span> <span class="n">next_proto_cb</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="k">return</span> <span class="n">ssl_ctx</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Create SSL object */</span>
<span class="k">static</span> <span class="n">SSL</span><span class="o">*</span> <span class="nf">create_ssl</span><span class="p">(</span><span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">SSL</span> <span class="o">*</span><span class="n">ssl</span><span class="p">;</span>
<span class="n">ssl</span> <span class="o">=</span> <span class="n">SSL_new</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">ssl</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not create SSL/TLS session object: %s&quot;</span><span class="p">,</span>
<span class="n">ERR_error_string</span><span class="p">(</span><span class="n">ERR_get_error</span><span class="p">(),</span> <span class="nb">NULL</span><span class="p">));</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">ssl</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">add_stream</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">,</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span> <span class="o">=</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">root</span><span class="p">.</span><span class="n">next</span><span class="p">;</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">root</span><span class="p">.</span><span class="n">next</span> <span class="o">=</span> <span class="n">stream_data</span><span class="p">;</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">prev</span> <span class="o">=</span> <span class="o">&amp;</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">root</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="p">)</span> <span class="p">{</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="o">-&gt;</span><span class="n">prev</span> <span class="o">=</span> <span class="n">stream_data</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">remove_stream</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">,</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">prev</span><span class="o">-&gt;</span><span class="n">next</span> <span class="o">=</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="p">)</span> <span class="p">{</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="o">-&gt;</span><span class="n">prev</span> <span class="o">=</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">prev</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="k">static</span> <span class="n">http2_stream_data</span><span class="o">*</span> <span class="nf">create_http2_stream_data</span>
<span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">,</span> <span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">malloc</span><span class="p">(</span><span class="k">sizeof</span><span class="p">(</span><span class="n">http2_stream_data</span><span class="p">));</span>
<span class="n">memset</span><span class="p">(</span><span class="n">stream_data</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">http2_stream_data</span><span class="p">));</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">stream_id</span> <span class="o">=</span> <span class="n">stream_id</span><span class="p">;</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">fd</span> <span class="o">=</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="n">add_stream</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">);</span>
<span class="k">return</span> <span class="n">stream_data</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">delete_http2_stream_data</span><span class="p">(</span><span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">fd</span> <span class="o">!=</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="n">close</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">fd</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">free</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">);</span>
<span class="n">free</span><span class="p">(</span><span class="n">stream_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">static</span> <span class="n">http2_session_data</span><span class="o">*</span> <span class="nf">create_http2_session_data</span><span class="p">(</span><span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">,</span>
<span class="kt">int</span> <span class="n">fd</span><span class="p">,</span>
<span class="k">struct</span> <span class="n">sockaddr</span> <span class="o">*</span><span class="n">addr</span><span class="p">,</span>
<span class="kt">int</span> <span class="n">addrlen</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">;</span>
<span class="n">SSL</span> <span class="o">*</span><span class="n">ssl</span><span class="p">;</span>
<span class="kt">char</span> <span class="n">host</span><span class="p">[</span><span class="n">NI_MAXHOST</span><span class="p">];</span>
<span class="kt">int</span> <span class="n">val</span> <span class="o">=</span> <span class="mi">1</span><span class="p">;</span>
<span class="n">ssl</span> <span class="o">=</span> <span class="n">create_ssl</span><span class="p">(</span><span class="n">app_ctx</span><span class="o">-&gt;</span><span class="n">ssl_ctx</span><span class="p">);</span>
<span class="n">session_data</span> <span class="o">=</span> <span class="n">malloc</span><span class="p">(</span><span class="k">sizeof</span><span class="p">(</span><span class="n">http2_session_data</span><span class="p">));</span>
<span class="n">memset</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">http2_session_data</span><span class="p">));</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">app_ctx</span> <span class="o">=</span> <span class="n">app_ctx</span><span class="p">;</span>
<span class="n">setsockopt</span><span class="p">(</span><span class="n">fd</span><span class="p">,</span> <span class="n">IPPROTO_TCP</span><span class="p">,</span> <span class="n">TCP_NODELAY</span><span class="p">,</span> <span class="p">(</span><span class="kt">char</span> <span class="o">*</span><span class="p">)</span><span class="o">&amp;</span><span class="n">val</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">val</span><span class="p">));</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span> <span class="o">=</span> <span class="n">bufferevent_openssl_socket_new</span>
<span class="p">(</span><span class="n">app_ctx</span><span class="o">-&gt;</span><span class="n">evbase</span><span class="p">,</span> <span class="n">fd</span><span class="p">,</span> <span class="n">ssl</span><span class="p">,</span>
<span class="n">BUFFEREVENT_SSL_ACCEPTING</span><span class="p">,</span>
<span class="n">BEV_OPT_CLOSE_ON_FREE</span> <span class="o">|</span> <span class="n">BEV_OPT_DEFER_CALLBACKS</span><span class="p">);</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span> <span class="o">=</span> <span class="n">NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">getnameinfo</span><span class="p">(</span><span class="n">addr</span><span class="p">,</span> <span class="n">addrlen</span><span class="p">,</span> <span class="n">host</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">host</span><span class="p">),</span> <span class="nb">NULL</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="n">NI_NUMERICHOST</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span> <span class="o">=</span> <span class="n">strdup</span><span class="p">(</span><span class="s">&quot;(unknown)&quot;</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span> <span class="o">=</span> <span class="n">strdup</span><span class="p">(</span><span class="n">host</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">session_data</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">delete_http2_session_data</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="n">SSL</span> <span class="o">*</span><span class="n">ssl</span> <span class="o">=</span> <span class="n">bufferevent_openssl_get_ssl</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s disconnected</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">ssl</span><span class="p">)</span> <span class="p">{</span>
<span class="n">SSL_shutdown</span><span class="p">(</span><span class="n">ssl</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">bufferevent_free</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="n">nghttp2_session_del</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">);</span>
<span class="k">for</span><span class="p">(</span><span class="n">stream_data</span> <span class="o">=</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">root</span><span class="p">.</span><span class="n">next</span><span class="p">;</span> <span class="n">stream_data</span><span class="p">;)</span> <span class="p">{</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">next</span> <span class="o">=</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">next</span><span class="p">;</span>
<span class="n">delete_http2_stream_data</span><span class="p">(</span><span class="n">stream_data</span><span class="p">);</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">next</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">free</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="n">free</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="cm">/* Serialize the frame and send (or buffer) the data to</span>
<span class="cm"> bufferevent. */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">session_send</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_session_send</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Read the data in the bufferevent and feed them into nghttp2 library</span>
<span class="cm"> function. Invocation of nghttp2_session_mem_recv() may make</span>
<span class="cm"> additional pending frames, so call session_send() at the end of the</span>
<span class="cm"> function. */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">session_recv</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">evbuffer</span> <span class="o">*</span><span class="n">input</span> <span class="o">=</span> <span class="n">bufferevent_get_input</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="kt">size_t</span> <span class="n">datalen</span> <span class="o">=</span> <span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">input</span><span class="p">);</span>
<span class="kt">unsigned</span> <span class="kt">char</span> <span class="o">*</span><span class="n">data</span> <span class="o">=</span> <span class="n">evbuffer_pullup</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">);</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_session_mem_recv</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">datalen</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">&lt;</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">evbuffer_drain</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="n">rv</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_send</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">ssize_t</span> <span class="nf">send_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">data</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">length</span><span class="p">,</span>
<span class="kt">int</span> <span class="n">flags</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span> <span class="o">=</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">;</span>
<span class="cm">/* Avoid excessive buffering in server side. */</span>
<span class="k">if</span><span class="p">(</span><span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">bufferevent_get_output</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">))</span> <span class="o">&gt;=</span>
<span class="n">OUTPUT_WOULDBLOCK_THRESHOLD</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_WOULDBLOCK</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">bufferevent_write</span><span class="p">(</span><span class="n">bev</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">length</span><span class="p">);</span>
<span class="k">return</span> <span class="n">length</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Returns nonzero if the string |s| ends with the substring |sub| */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">ends_with</span><span class="p">(</span><span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">s</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">sub</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">size_t</span> <span class="n">slen</span> <span class="o">=</span> <span class="n">strlen</span><span class="p">(</span><span class="n">s</span><span class="p">);</span>
<span class="kt">size_t</span> <span class="n">sublen</span> <span class="o">=</span> <span class="n">strlen</span><span class="p">(</span><span class="n">sub</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">slen</span> <span class="o">&lt;</span> <span class="n">sublen</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">memcmp</span><span class="p">(</span><span class="n">s</span> <span class="o">+</span> <span class="n">slen</span> <span class="o">-</span> <span class="n">sublen</span><span class="p">,</span> <span class="n">sub</span><span class="p">,</span> <span class="n">sublen</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Returns int value of hex string character |c| */</span>
<span class="k">static</span> <span class="kt">uint8_t</span> <span class="nf">hex_to_uint</span><span class="p">(</span><span class="kt">uint8_t</span> <span class="n">c</span><span class="p">)</span>
<span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="sc">&#39;0&#39;</span> <span class="o">&lt;=</span> <span class="n">c</span> <span class="o">&amp;&amp;</span> <span class="n">c</span> <span class="o">&lt;=</span> <span class="sc">&#39;9&#39;</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">c</span> <span class="o">-</span> <span class="sc">&#39;0&#39;</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="sc">&#39;A&#39;</span> <span class="o">&lt;=</span> <span class="n">c</span> <span class="o">&amp;&amp;</span> <span class="n">c</span> <span class="o">&lt;=</span> <span class="sc">&#39;F&#39;</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">c</span> <span class="o">-</span> <span class="sc">&#39;A&#39;</span> <span class="o">+</span> <span class="mi">10</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="sc">&#39;a&#39;</span> <span class="o">&lt;=</span> <span class="n">c</span> <span class="o">&amp;&amp;</span> <span class="n">c</span> <span class="o">&lt;=</span> <span class="sc">&#39;f&#39;</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">c</span> <span class="o">-</span> <span class="sc">&#39;a&#39;</span> <span class="o">+</span> <span class="mi">10</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Decodes percent-encoded byte string |value| with length |valuelen|</span>
<span class="cm"> and returns the decoded byte string in allocated buffer. The return</span>
<span class="cm"> value is NULL terminated. The caller must free the returned</span>
<span class="cm"> string. */</span>
<span class="k">static</span> <span class="kt">char</span><span class="o">*</span> <span class="nf">percent_decode</span><span class="p">(</span><span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">value</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">valuelen</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">res</span><span class="p">;</span>
<span class="n">res</span> <span class="o">=</span> <span class="n">malloc</span><span class="p">(</span><span class="n">valuelen</span> <span class="o">+</span> <span class="mi">1</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">valuelen</span> <span class="o">&gt;</span> <span class="mi">3</span><span class="p">)</span> <span class="p">{</span>
<span class="kt">size_t</span> <span class="n">i</span><span class="p">,</span> <span class="n">j</span><span class="p">;</span>
<span class="k">for</span><span class="p">(</span><span class="n">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">,</span> <span class="n">j</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="n">i</span> <span class="o">&lt;</span> <span class="n">valuelen</span> <span class="o">-</span> <span class="mi">2</span><span class="p">;)</span> <span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="n">value</span><span class="p">[</span><span class="n">i</span><span class="p">]</span> <span class="o">!=</span> <span class="sc">&#39;%&#39;</span> <span class="o">||</span>
<span class="o">!</span><span class="n">isxdigit</span><span class="p">(</span><span class="n">value</span><span class="p">[</span><span class="n">i</span> <span class="o">+</span> <span class="mi">1</span><span class="p">])</span> <span class="o">||</span> <span class="o">!</span><span class="n">isxdigit</span><span class="p">(</span><span class="n">value</span><span class="p">[</span><span class="n">i</span> <span class="o">+</span> <span class="mi">2</span><span class="p">]))</span> <span class="p">{</span>
<span class="n">res</span><span class="p">[</span><span class="n">j</span><span class="o">++</span><span class="p">]</span> <span class="o">=</span> <span class="n">value</span><span class="p">[</span><span class="n">i</span><span class="o">++</span><span class="p">];</span>
<span class="k">continue</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">res</span><span class="p">[</span><span class="n">j</span><span class="o">++</span><span class="p">]</span> <span class="o">=</span> <span class="p">(</span><span class="n">hex_to_uint</span><span class="p">(</span><span class="n">value</span><span class="p">[</span><span class="n">i</span> <span class="o">+</span> <span class="mi">1</span><span class="p">])</span> <span class="o">&lt;&lt;</span> <span class="mi">4</span><span class="p">)</span> <span class="o">+</span> <span class="n">hex_to_uint</span><span class="p">(</span><span class="n">value</span><span class="p">[</span><span class="n">i</span> <span class="o">+</span> <span class="mi">2</span><span class="p">]);</span>
<span class="n">i</span> <span class="o">+=</span> <span class="mi">3</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">memcpy</span><span class="p">(</span><span class="o">&amp;</span><span class="n">res</span><span class="p">[</span><span class="n">j</span><span class="p">],</span> <span class="o">&amp;</span><span class="n">value</span><span class="p">[</span><span class="n">i</span><span class="p">],</span> <span class="mi">2</span><span class="p">);</span>
<span class="n">res</span><span class="p">[</span><span class="n">j</span> <span class="o">+</span> <span class="mi">2</span><span class="p">]</span> <span class="o">=</span> <span class="sc">&#39;\0&#39;</span><span class="p">;</span>
<span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="n">memcpy</span><span class="p">(</span><span class="n">res</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">valuelen</span><span class="p">);</span>
<span class="n">res</span><span class="p">[</span><span class="n">valuelen</span><span class="p">]</span> <span class="o">=</span> <span class="sc">&#39;\0&#39;</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">res</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">ssize_t</span> <span class="nf">file_read_callback</span>
<span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span> <span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="kt">uint8_t</span> <span class="o">*</span><span class="n">buf</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">length</span><span class="p">,</span> <span class="kt">uint32_t</span> <span class="o">*</span><span class="n">data_flags</span><span class="p">,</span>
<span class="n">nghttp2_data_source</span> <span class="o">*</span><span class="n">source</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">fd</span> <span class="o">=</span> <span class="n">source</span><span class="o">-&gt;</span><span class="n">fd</span><span class="p">;</span>
<span class="kt">ssize_t</span> <span class="n">r</span><span class="p">;</span>
<span class="k">while</span><span class="p">((</span><span class="n">r</span> <span class="o">=</span> <span class="n">read</span><span class="p">(</span><span class="n">fd</span><span class="p">,</span> <span class="n">buf</span><span class="p">,</span> <span class="n">length</span><span class="p">))</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span> <span class="o">&amp;&amp;</span> <span class="n">errno</span> <span class="o">==</span> <span class="n">EINTR</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">r</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">r</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="o">*</span><span class="n">data_flags</span> <span class="o">|=</span> <span class="n">NGHTTP2_DATA_FLAG_EOF</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">r</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">send_response</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span> <span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="n">nghttp2_nv</span> <span class="o">*</span><span class="n">nva</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">nvlen</span><span class="p">,</span> <span class="kt">int</span> <span class="n">fd</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">nghttp2_data_provider</span> <span class="n">data_prd</span><span class="p">;</span>
<span class="n">data_prd</span><span class="p">.</span><span class="n">source</span><span class="p">.</span><span class="n">fd</span> <span class="o">=</span> <span class="n">fd</span><span class="p">;</span>
<span class="n">data_prd</span><span class="p">.</span><span class="n">read_callback</span> <span class="o">=</span> <span class="n">file_read_callback</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_submit_response</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_id</span><span class="p">,</span> <span class="n">nva</span><span class="p">,</span> <span class="n">nvlen</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">data_prd</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">const</span> <span class="kt">char</span> <span class="n">ERROR_HTML</span><span class="p">[]</span> <span class="o">=</span> <span class="s">&quot;&lt;html&gt;&lt;head&gt;&lt;title&gt;404&lt;/title&gt;&lt;/head&gt;&quot;</span>
<span class="s">&quot;&lt;body&gt;&lt;h1&gt;404 Not Found&lt;/h1&gt;&lt;/body&gt;&lt;/html&gt;&quot;</span><span class="p">;</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">error_reply</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="kt">int</span> <span class="n">pipefd</span><span class="p">[</span><span class="mi">2</span><span class="p">];</span>
<span class="n">nghttp2_nv</span> <span class="n">hdrs</span><span class="p">[]</span> <span class="o">=</span> <span class="p">{</span>
<span class="n">MAKE_NV</span><span class="p">(</span><span class="s">&quot;:status&quot;</span><span class="p">,</span> <span class="s">&quot;404&quot;</span><span class="p">)</span>
<span class="p">};</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">pipe</span><span class="p">(</span><span class="n">pipefd</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warn</span><span class="p">(</span><span class="s">&quot;Could not create pipe&quot;</span><span class="p">);</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_submit_rst_stream</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">NGHTTP2_FLAG_NONE</span><span class="p">,</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">stream_id</span><span class="p">,</span>
<span class="n">NGHTTP2_INTERNAL_ERROR</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">write</span><span class="p">(</span><span class="n">pipefd</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">ERROR_HTML</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">ERROR_HTML</span><span class="p">)</span> <span class="o">-</span> <span class="mi">1</span><span class="p">);</span>
<span class="n">close</span><span class="p">(</span><span class="n">pipefd</span><span class="p">[</span><span class="mi">1</span><span class="p">]);</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">fd</span> <span class="o">=</span> <span class="n">pipefd</span><span class="p">[</span><span class="mi">0</span><span class="p">];</span>
<span class="k">if</span><span class="p">(</span><span class="n">send_response</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">stream_id</span><span class="p">,</span> <span class="n">hdrs</span><span class="p">,</span> <span class="n">ARRLEN</span><span class="p">(</span><span class="n">hdrs</span><span class="p">),</span>
<span class="n">pipefd</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">close</span><span class="p">(</span><span class="n">pipefd</span><span class="p">[</span><span class="mi">0</span><span class="p">]);</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* nghttp2_on_header_callback: Called when nghttp2 library emits</span>
<span class="cm"> single header name/value pair. */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">on_header_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">name</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">namelen</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">uint8_t</span> <span class="o">*</span><span class="n">value</span><span class="p">,</span> <span class="kt">size_t</span> <span class="n">valuelen</span><span class="p">,</span>
<span class="kt">uint8_t</span> <span class="n">flags</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">const</span> <span class="kt">char</span> <span class="n">PATH</span><span class="p">[]</span> <span class="o">=</span> <span class="s">&quot;:path&quot;</span><span class="p">;</span>
<span class="k">switch</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span><span class="p">)</span> <span class="p">{</span>
<span class="k">case</span> <span class="n">NGHTTP2_HEADERS</span>:
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">headers</span><span class="p">.</span><span class="n">cat</span> <span class="o">!=</span> <span class="n">NGHTTP2_HCAT_REQUEST</span><span class="p">)</span> <span class="p">{</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span> <span class="o">||</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">)</span> <span class="p">{</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">namelen</span> <span class="o">==</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">PATH</span><span class="p">)</span> <span class="o">-</span> <span class="mi">1</span> <span class="o">&amp;&amp;</span> <span class="n">memcmp</span><span class="p">(</span><span class="n">PATH</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">namelen</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="kt">size_t</span> <span class="n">j</span><span class="p">;</span>
<span class="k">for</span><span class="p">(</span><span class="n">j</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="n">j</span> <span class="o">&lt;</span> <span class="n">valuelen</span> <span class="o">&amp;&amp;</span> <span class="n">value</span><span class="p">[</span><span class="n">j</span><span class="p">]</span> <span class="o">!=</span> <span class="sc">&#39;?&#39;</span><span class="p">;</span> <span class="o">++</span><span class="n">j</span><span class="p">);</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span> <span class="o">=</span> <span class="n">percent_decode</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">j</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">on_begin_headers_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span> <span class="o">!=</span> <span class="n">NGHTTP2_HEADERS</span> <span class="o">||</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">headers</span><span class="p">.</span><span class="n">cat</span> <span class="o">!=</span> <span class="n">NGHTTP2_HCAT_REQUEST</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">create_http2_stream_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="n">nghttp2_session_set_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">,</span>
<span class="n">stream_data</span><span class="p">);</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* Minimum check for directory traversal. Returns nonzero if it is</span>
<span class="cm"> safe. */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">check_path</span><span class="p">(</span><span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">path</span><span class="p">)</span>
<span class="p">{</span>
<span class="cm">/* We don&#39;t like &#39;\&#39; in url. */</span>
<span class="k">return</span> <span class="n">path</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">&amp;&amp;</span> <span class="n">path</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">==</span> <span class="sc">&#39;/&#39;</span> <span class="o">&amp;&amp;</span>
<span class="n">strchr</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="sc">&#39;\\&#39;</span><span class="p">)</span> <span class="o">==</span> <span class="nb">NULL</span> <span class="o">&amp;&amp;</span>
<span class="n">strstr</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="s">&quot;/../&quot;</span><span class="p">)</span> <span class="o">==</span> <span class="nb">NULL</span> <span class="o">&amp;&amp;</span>
<span class="n">strstr</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="s">&quot;/./&quot;</span><span class="p">)</span> <span class="o">==</span> <span class="nb">NULL</span> <span class="o">&amp;&amp;</span>
<span class="o">!</span><span class="n">ends_with</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="s">&quot;/..&quot;</span><span class="p">)</span> <span class="o">&amp;&amp;</span> <span class="o">!</span><span class="n">ends_with</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="s">&quot;/.&quot;</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">on_request_recv</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">,</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">fd</span><span class="p">;</span>
<span class="n">nghttp2_nv</span> <span class="n">hdrs</span><span class="p">[]</span> <span class="o">=</span> <span class="p">{</span>
<span class="n">MAKE_NV</span><span class="p">(</span><span class="s">&quot;:status&quot;</span><span class="p">,</span> <span class="s">&quot;200&quot;</span><span class="p">)</span>
<span class="p">};</span>
<span class="kt">char</span> <span class="o">*</span><span class="n">rel_path</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="n">error_reply</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s GET %s</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">,</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">check_path</span><span class="p">(</span><span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">))</span> <span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="n">error_reply</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">for</span><span class="p">(</span><span class="n">rel_path</span> <span class="o">=</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">request_path</span><span class="p">;</span> <span class="o">*</span><span class="n">rel_path</span> <span class="o">==</span> <span class="sc">&#39;/&#39;</span><span class="p">;</span> <span class="o">++</span><span class="n">rel_path</span><span class="p">);</span>
<span class="n">fd</span> <span class="o">=</span> <span class="n">open</span><span class="p">(</span><span class="n">rel_path</span><span class="p">,</span> <span class="n">O_RDONLY</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">fd</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span><span class="p">(</span><span class="n">error_reply</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">fd</span> <span class="o">=</span> <span class="n">fd</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">send_response</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_data</span><span class="o">-&gt;</span><span class="n">stream_id</span><span class="p">,</span> <span class="n">hdrs</span><span class="p">,</span>
<span class="n">ARRLEN</span><span class="p">(</span><span class="n">hdrs</span><span class="p">),</span> <span class="n">fd</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">close</span><span class="p">(</span><span class="n">fd</span><span class="p">);</span>
<span class="k">return</span> <span class="n">NGHTTP2_ERR_CALLBACK_FAILURE</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">on_frame_recv_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="k">const</span> <span class="n">nghttp2_frame</span> <span class="o">*</span><span class="n">frame</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="k">switch</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">type</span><span class="p">)</span> <span class="p">{</span>
<span class="k">case</span> <span class="n">NGHTTP2_DATA</span>:
<span class="k">case</span> <span class="n">NGHTTP2_HEADERS</span>:
<span class="cm">/* Check that the client request has finished */</span>
<span class="k">if</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">flags</span> <span class="o">&amp;</span> <span class="n">NGHTTP2_FLAG_END_STREAM</span><span class="p">)</span> <span class="p">{</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span>
<span class="n">frame</span><span class="o">-&gt;</span><span class="n">hd</span><span class="p">.</span><span class="n">stream_id</span><span class="p">);</span>
<span class="cm">/* For DATA and HEADERS frame, this callback may be called after</span>
<span class="cm"> on_stream_close_callback. Check that stream still alive. */</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">on_request_recv</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">session_data</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">break</span><span class="p">;</span>
<span class="nl">default:</span>
<span class="k">break</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">on_stream_close_callback</span><span class="p">(</span><span class="n">nghttp2_session</span> <span class="o">*</span><span class="n">session</span><span class="p">,</span>
<span class="kt">int32_t</span> <span class="n">stream_id</span><span class="p">,</span>
<span class="n">nghttp2_error_code</span> <span class="n">error_code</span><span class="p">,</span>
<span class="kt">void</span> <span class="o">*</span><span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">user_data</span><span class="p">;</span>
<span class="n">http2_stream_data</span> <span class="o">*</span><span class="n">stream_data</span><span class="p">;</span>
<span class="n">stream_data</span> <span class="o">=</span> <span class="n">nghttp2_session_get_stream_user_data</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">stream_id</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="o">!</span><span class="n">stream_data</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">remove_stream</span><span class="p">(</span><span class="n">session_data</span><span class="p">,</span> <span class="n">stream_data</span><span class="p">);</span>
<span class="n">delete_http2_stream_data</span><span class="p">(</span><span class="n">stream_data</span><span class="p">);</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">initialize_nghttp2_session</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">nghttp2_session_callbacks</span> <span class="n">callbacks</span> <span class="o">=</span> <span class="p">{</span><span class="mi">0</span><span class="p">};</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">send_callback</span> <span class="o">=</span> <span class="n">send_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_frame_recv_callback</span> <span class="o">=</span> <span class="n">on_frame_recv_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_stream_close_callback</span> <span class="o">=</span> <span class="n">on_stream_close_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_header_callback</span> <span class="o">=</span> <span class="n">on_header_callback</span><span class="p">;</span>
<span class="n">callbacks</span><span class="p">.</span><span class="n">on_begin_headers_callback</span> <span class="o">=</span> <span class="n">on_begin_headers_callback</span><span class="p">;</span>
<span class="n">nghttp2_session_server_new</span><span class="p">(</span><span class="o">&amp;</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">callbacks</span><span class="p">,</span> <span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="cm">/* Send HTTP/2 client connection header, which includes 24 bytes</span>
<span class="cm"> magic octets and SETTINGS frame */</span>
<span class="k">static</span> <span class="kt">int</span> <span class="nf">send_server_connection_header</span><span class="p">(</span><span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">nghttp2_settings_entry</span> <span class="n">iv</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span> <span class="o">=</span> <span class="p">{</span>
<span class="p">{</span> <span class="n">NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS</span><span class="p">,</span> <span class="mi">100</span> <span class="p">}</span>
<span class="p">};</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">nghttp2_submit_settings</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">,</span> <span class="n">NGHTTP2_FLAG_NONE</span><span class="p">,</span>
<span class="n">iv</span><span class="p">,</span> <span class="n">ARRLEN</span><span class="p">(</span><span class="n">iv</span><span class="p">));</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">warnx</span><span class="p">(</span><span class="s">&quot;Fatal error: %s&quot;</span><span class="p">,</span> <span class="n">nghttp2_strerror</span><span class="p">(</span><span class="n">rv</span><span class="p">));</span>
<span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
<span class="cm">/* readcb for bufferevent after client connection header was</span>
<span class="cm"> checked. */</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">readcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_recv</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="cm">/* writecb for bufferevent. To greaceful shutdown after sending or</span>
<span class="cm"> receiving GOAWAY, we check the some conditions on the nghttp2</span>
<span class="cm"> library and output buffer of bufferevent. If it indicates we have</span>
<span class="cm"> no business to this session, tear down the connection. If the</span>
<span class="cm"> connection is not going to shutdown, we call session_send() to</span>
<span class="cm"> process pending data in the output buffer. This is necessary</span>
<span class="cm"> because we have a threshold on the buffer size to avoid too much</span>
<span class="cm"> buffering. See send_callback(). */</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">writecb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">evbuffer_get_length</span><span class="p">(</span><span class="n">bufferevent_get_output</span><span class="p">(</span><span class="n">bev</span><span class="p">))</span> <span class="o">&gt;</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">nghttp2_session_want_read</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span> <span class="o">&amp;&amp;</span>
<span class="n">nghttp2_session_want_write</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">session</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_send</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="cm">/* eventcb for bufferevent */</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">eventcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">short</span> <span class="n">events</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_CONNECTED</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s connected</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_EOF</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s EOF</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_ERROR</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s network error</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span><span class="p">(</span><span class="n">events</span> <span class="o">&amp;</span> <span class="n">BEV_EVENT_TIMEOUT</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;%s timeout</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">client_addr</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="cm">/* readcb for bufferevent to check first 24 bytes client connection</span>
<span class="cm"> header. */</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">handshake_readcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">bufferevent</span> <span class="o">*</span><span class="n">bev</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">ptr</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span> <span class="o">=</span> <span class="p">(</span><span class="n">http2_session_data</span><span class="o">*</span><span class="p">)</span><span class="n">ptr</span><span class="p">;</span>
<span class="kt">uint8_t</span> <span class="n">data</span><span class="p">[</span><span class="mi">24</span><span class="p">];</span>
<span class="k">struct</span> <span class="n">evbuffer</span> <span class="o">*</span><span class="n">input</span> <span class="o">=</span> <span class="n">bufferevent_get_input</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">);</span>
<span class="kt">int</span> <span class="n">readlen</span> <span class="o">=</span> <span class="n">evbuffer_remove</span><span class="p">(</span><span class="n">input</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span><span class="p">);</span>
<span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">conhead</span> <span class="o">=</span> <span class="n">NGHTTP2_CLIENT_CONNECTION_PREFACE</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">memcmp</span><span class="p">(</span><span class="n">conhead</span> <span class="o">+</span> <span class="n">NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN</span>
<span class="o">-</span> <span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span><span class="p">,</span> <span class="n">data</span><span class="p">,</span> <span class="n">readlen</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span> <span class="o">-=</span> <span class="n">readlen</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">handshake_leftlen</span> <span class="o">==</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">bufferevent_setcb</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">,</span> <span class="n">readcb</span><span class="p">,</span> <span class="n">writecb</span><span class="p">,</span> <span class="n">eventcb</span><span class="p">,</span> <span class="n">ptr</span><span class="p">);</span>
<span class="cm">/* Process pending data in buffer since they are not notified</span>
<span class="cm"> further */</span>
<span class="n">initialize_nghttp2_session</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">send_server_connection_header</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span><span class="p">(</span><span class="n">session_recv</span><span class="p">(</span><span class="n">session_data</span><span class="p">)</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">delete_http2_session_data</span><span class="p">(</span><span class="n">session_data</span><span class="p">);</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="cm">/* callback for evconnlistener */</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">acceptcb</span><span class="p">(</span><span class="k">struct</span> <span class="n">evconnlistener</span> <span class="o">*</span><span class="n">listener</span><span class="p">,</span> <span class="kt">int</span> <span class="n">fd</span><span class="p">,</span>
<span class="k">struct</span> <span class="n">sockaddr</span> <span class="o">*</span><span class="n">addr</span><span class="p">,</span> <span class="kt">int</span> <span class="n">addrlen</span><span class="p">,</span> <span class="kt">void</span> <span class="o">*</span><span class="n">arg</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span> <span class="o">=</span> <span class="p">(</span><span class="n">app_context</span><span class="o">*</span><span class="p">)</span><span class="n">arg</span><span class="p">;</span>
<span class="n">http2_session_data</span> <span class="o">*</span><span class="n">session_data</span><span class="p">;</span>
<span class="n">session_data</span> <span class="o">=</span> <span class="n">create_http2_session_data</span><span class="p">(</span><span class="n">app_ctx</span><span class="p">,</span> <span class="n">fd</span><span class="p">,</span> <span class="n">addr</span><span class="p">,</span> <span class="n">addrlen</span><span class="p">);</span>
<span class="n">bufferevent_setcb</span><span class="p">(</span><span class="n">session_data</span><span class="o">-&gt;</span><span class="n">bev</span><span class="p">,</span> <span class="n">handshake_readcb</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">,</span> <span class="n">eventcb</span><span class="p">,</span>
<span class="n">session_data</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">start_listen</span><span class="p">(</span><span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">service</span><span class="p">,</span>
<span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">)</span>
<span class="p">{</span>
<span class="kt">int</span> <span class="n">rv</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">addrinfo</span> <span class="n">hints</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">addrinfo</span> <span class="o">*</span><span class="n">res</span><span class="p">,</span> <span class="o">*</span><span class="n">rp</span><span class="p">;</span>
<span class="n">memset</span><span class="p">(</span><span class="o">&amp;</span><span class="n">hints</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">hints</span><span class="p">));</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_family</span> <span class="o">=</span> <span class="n">AF_UNSPEC</span><span class="p">;</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_socktype</span> <span class="o">=</span> <span class="n">SOCK_STREAM</span><span class="p">;</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_flags</span> <span class="o">=</span> <span class="n">AI_PASSIVE</span><span class="p">;</span>
<span class="cp">#ifdef AI_ADDRCONFIG</span>
<span class="n">hints</span><span class="p">.</span><span class="n">ai_flags</span> <span class="o">|=</span> <span class="n">AI_ADDRCONFIG</span><span class="p">;</span>
<span class="cp">#endif </span><span class="c1">// AI_ADDRCONFIG</span>
<span class="n">rv</span> <span class="o">=</span> <span class="n">getaddrinfo</span><span class="p">(</span><span class="nb">NULL</span><span class="p">,</span> <span class="n">service</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">hints</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">res</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">rv</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">for</span><span class="p">(</span><span class="n">rp</span> <span class="o">=</span> <span class="n">res</span><span class="p">;</span> <span class="n">rp</span><span class="p">;</span> <span class="n">rp</span> <span class="o">=</span> <span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_next</span><span class="p">)</span> <span class="p">{</span>
<span class="k">struct</span> <span class="n">evconnlistener</span> <span class="o">*</span><span class="n">listener</span><span class="p">;</span>
<span class="n">listener</span> <span class="o">=</span> <span class="n">evconnlistener_new_bind</span><span class="p">(</span><span class="n">evbase</span><span class="p">,</span> <span class="n">acceptcb</span><span class="p">,</span> <span class="n">app_ctx</span><span class="p">,</span>
<span class="n">LEV_OPT_CLOSE_ON_FREE</span> <span class="o">|</span>
<span class="n">LEV_OPT_REUSEABLE</span><span class="p">,</span> <span class="mi">16</span><span class="p">,</span>
<span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_addr</span><span class="p">,</span> <span class="n">rp</span><span class="o">-&gt;</span><span class="n">ai_addrlen</span><span class="p">);</span>
<span class="k">if</span><span class="p">(</span><span class="n">listener</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span><span class="p">;</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="n">errx</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="s">&quot;Could not start listener&quot;</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">initialize_app_context</span><span class="p">(</span><span class="n">app_context</span> <span class="o">*</span><span class="n">app_ctx</span><span class="p">,</span> <span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">,</span>
<span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">memset</span><span class="p">(</span><span class="n">app_ctx</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="n">app_context</span><span class="p">));</span>
<span class="n">app_ctx</span><span class="o">-&gt;</span><span class="n">ssl_ctx</span> <span class="o">=</span> <span class="n">ssl_ctx</span><span class="p">;</span>
<span class="n">app_ctx</span><span class="o">-&gt;</span><span class="n">evbase</span> <span class="o">=</span> <span class="n">evbase</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">static</span> <span class="kt">void</span> <span class="nf">run</span><span class="p">(</span><span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">service</span><span class="p">,</span>
<span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">key_file</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">cert_file</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">SSL_CTX</span> <span class="o">*</span><span class="n">ssl_ctx</span><span class="p">;</span>
<span class="n">app_context</span> <span class="n">app_ctx</span><span class="p">;</span>
<span class="k">struct</span> <span class="n">event_base</span> <span class="o">*</span><span class="n">evbase</span><span class="p">;</span>
<span class="n">ssl_ctx</span> <span class="o">=</span> <span class="n">create_ssl_ctx</span><span class="p">(</span><span class="n">key_file</span><span class="p">,</span> <span class="n">cert_file</span><span class="p">);</span>
<span class="n">evbase</span> <span class="o">=</span> <span class="n">event_base_new</span><span class="p">();</span>
<span class="n">initialize_app_context</span><span class="p">(</span><span class="o">&amp;</span><span class="n">app_ctx</span><span class="p">,</span> <span class="n">ssl_ctx</span><span class="p">,</span> <span class="n">evbase</span><span class="p">);</span>
<span class="n">start_listen</span><span class="p">(</span><span class="n">evbase</span><span class="p">,</span> <span class="n">service</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">app_ctx</span><span class="p">);</span>
<span class="n">event_base_loop</span><span class="p">(</span><span class="n">evbase</span><span class="p">,</span> <span class="mi">0</span><span class="p">);</span>
<span class="n">event_base_free</span><span class="p">(</span><span class="n">evbase</span><span class="p">);</span>
<span class="n">SSL_CTX_free</span><span class="p">(</span><span class="n">ssl_ctx</span><span class="p">);</span>
<span class="p">}</span>
<span class="kt">int</span> <span class="nf">main</span><span class="p">(</span><span class="kt">int</span> <span class="n">argc</span><span class="p">,</span> <span class="kt">char</span> <span class="o">**</span><span class="n">argv</span><span class="p">)</span>
<span class="p">{</span>
<span class="k">struct</span> <span class="n">sigaction</span> <span class="n">act</span><span class="p">;</span>
<span class="k">if</span><span class="p">(</span><span class="n">argc</span> <span class="o">&lt;</span> <span class="mi">4</span><span class="p">)</span> <span class="p">{</span>
<span class="n">fprintf</span><span class="p">(</span><span class="n">stderr</span><span class="p">,</span> <span class="s">&quot;Usage: libevent-server PORT KEY_FILE CERT_FILE</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">);</span>
<span class="n">exit</span><span class="p">(</span><span class="n">EXIT_FAILURE</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">memset</span><span class="p">(</span><span class="o">&amp;</span><span class="n">act</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="k">sizeof</span><span class="p">(</span><span class="k">struct</span> <span class="n">sigaction</span><span class="p">));</span>
<span class="n">act</span><span class="p">.</span><span class="n">sa_handler</span> <span class="o">=</span> <span class="n">SIG_IGN</span><span class="p">;</span>
<span class="n">sigaction</span><span class="p">(</span><span class="n">SIGPIPE</span><span class="p">,</span> <span class="o">&amp;</span><span class="n">act</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="n">SSL_load_error_strings</span><span class="p">();</span>
<span class="n">SSL_library_init</span><span class="p">();</span>
<span class="n">run</span><span class="p">(</span><span class="n">argv</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">argv</span><span class="p">[</span><span class="mi">2</span><span class="p">],</span> <span class="n">argv</span><span class="p">[</span><span class="mi">3</span><span class="p">]);</span>
<span class="k">return</span> <span class="mi">0</span><span class="p">;</span>
<span class="p">}</span>
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