Update tutorial

This commit is contained in:
Tatsuhiro Tsujikawa 2014-11-30 21:10:59 +09:00
parent 2b465ee65f
commit f2cd057e89
2 changed files with 187 additions and 228 deletions

View File

@ -22,12 +22,10 @@ protocol over the SSL/TLS transport. In this tutorial, we use
`nghttp2_select_next_protocol()` function to select the HTTP/2
protocol the library supports::
static int select_next_proto_cb(SSL* ssl,
unsigned char **out, unsigned char *outlen,
const unsigned char *in, unsigned int inlen,
void *arg)
{
if(nghttp2_select_next_protocol(out, outlen, in, inlen) <= 0) {
static int select_next_proto_cb(SSL *ssl _U_, unsigned char **out,
unsigned char *outlen, const unsigned char *in,
unsigned int inlen, void *arg _U_) {
if (nghttp2_select_next_protocol(out, outlen, in, inlen) <= 0) {
errx(1, "Server did not advertise " NGHTTP2_PROTO_VERSION_ID);
}
return SSL_TLSEXT_ERR_OK;
@ -36,17 +34,17 @@ protocol the library supports::
The callback is set to the SSL_CTX object using
``SSL_CTX_set_next_proto_select_cb()`` function::
static SSL_CTX* create_ssl_ctx(void)
{
static SSL_CTX *create_ssl_ctx(void) {
SSL_CTX *ssl_ctx;
ssl_ctx = SSL_CTX_new(SSLv23_client_method());
if(!ssl_ctx) {
if (!ssl_ctx) {
errx(1, "Could not create SSL/TLS context: %s",
ERR_error_string(ERR_get_error(), NULL));
}
SSL_CTX_set_options(ssl_ctx,
SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_COMPRESSION |
SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION);
SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
SSL_OP_NO_COMPRESSION |
SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION);
SSL_CTX_set_next_proto_select_cb(ssl_ctx, select_next_proto_cb, NULL);
return ssl_ctx;
}
@ -91,25 +89,22 @@ respectively.
Then we call function ``initiate_connection()`` to start connecting to
the remote server::
static void initiate_connection(struct event_base *evbase,
SSL_CTX *ssl_ctx,
static void initiate_connection(struct event_base *evbase, SSL_CTX *ssl_ctx,
const char *host, uint16_t port,
http2_session_data *session_data)
{
http2_session_data *session_data) {
int rv;
struct bufferevent *bev;
SSL *ssl;
ssl = create_ssl(ssl_ctx);
bev = bufferevent_openssl_socket_new(evbase, -1, ssl,
BUFFEREVENT_SSL_CONNECTING,
BEV_OPT_DEFER_CALLBACKS |
BEV_OPT_CLOSE_ON_FREE);
bev = bufferevent_openssl_socket_new(
evbase, -1, ssl, BUFFEREVENT_SSL_CONNECTING,
BEV_OPT_DEFER_CALLBACKS | BEV_OPT_CLOSE_ON_FREE);
bufferevent_setcb(bev, readcb, writecb, eventcb, session_data);
rv = bufferevent_socket_connect_hostname(bev, session_data->dnsbase,
AF_UNSPEC, host, port);
if(rv != 0) {
if (rv != 0) {
errx(1, "Could not connect to the remote host %s", host);
}
session_data->bev = bev;
@ -122,10 +117,9 @@ The ``eventcb()`` is invoked by libevent event loop when an event
(e.g., connection has been established, timeout, etc) happens on the
underlying network socket::
static void eventcb(struct bufferevent *bev, short events, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
if(events & BEV_EVENT_CONNECTED) {
static void eventcb(struct bufferevent *bev, short events, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
if (events & BEV_EVENT_CONNECTED) {
int fd = bufferevent_getfd(bev);
int val = 1;
fprintf(stderr, "Connected\n");
@ -133,16 +127,16 @@ underlying network socket::
initialize_nghttp2_session(session_data);
send_client_connection_header(session_data);
submit_request(session_data);
if(session_send(session_data) != 0) {
if (session_send(session_data) != 0) {
delete_http2_session_data(session_data);
}
return;
}
if(events & BEV_EVENT_EOF) {
if (events & BEV_EVENT_EOF) {
warnx("Disconnected from the remote host");
} else if(events & BEV_EVENT_ERROR) {
} else if (events & BEV_EVENT_ERROR) {
warnx("Network error");
} else if(events & BEV_EVENT_TIMEOUT) {
} else if (events & BEV_EVENT_TIMEOUT) {
warnx("Timeout");
}
delete_http2_session_data(session_data);
@ -154,28 +148,27 @@ event, we just simply tear down the connection. The
finished successfully. We first initialize nghttp2 session object in
``initialize_nghttp2_session()`` function::
static void initialize_nghttp2_session(http2_session_data *session_data)
{
static void initialize_nghttp2_session(http2_session_data *session_data) {
nghttp2_session_callbacks *callbacks;
nghttp2_session_callbacks_new(&callbacks);
nghttp2_session_callbacks_set_send_callback(callbacks, send_callback);
nghttp2_session_callbacks_set_on_frame_recv_callback
(callbacks, on_frame_recv_callback);
nghttp2_session_callbacks_set_on_frame_recv_callback(callbacks,
on_frame_recv_callback);
nghttp2_session_callbacks_set_on_data_chunk_recv_callback
(callbacks, on_data_chunk_recv_callback);
nghttp2_session_callbacks_set_on_data_chunk_recv_callback(
callbacks, on_data_chunk_recv_callback);
nghttp2_session_callbacks_set_on_stream_close_callback
(callbacks, on_stream_close_callback);
nghttp2_session_callbacks_set_on_stream_close_callback(
callbacks, on_stream_close_callback);
nghttp2_session_callbacks_set_on_header_callback
(callbacks, on_header_callback);
nghttp2_session_callbacks_set_on_header_callback(callbacks,
on_header_callback);
nghttp2_session_callbacks_set_on_begin_headers_callback
(callbacks, on_begin_headers_callback);
nghttp2_session_callbacks_set_on_begin_headers_callback(
callbacks, on_begin_headers_callback);
nghttp2_session_client_new(&session_data->session, callbacks, session_data);
@ -196,19 +189,16 @@ which is 24 bytes magic byte sequence
transmission of client connection header is done in
``send_client_connection_header()``::
static void send_client_connection_header(http2_session_data *session_data)
{
static void send_client_connection_header(http2_session_data *session_data) {
nghttp2_settings_entry iv[1] = {
{ NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 100 }
};
{NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 100}};
int rv;
bufferevent_write(session_data->bev,
NGHTTP2_CLIENT_CONNECTION_PREFACE,
bufferevent_write(session_data->bev, NGHTTP2_CLIENT_CONNECTION_PREFACE,
NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN);
rv = nghttp2_submit_settings(session_data->session, NGHTTP2_FLAG_NONE,
iv, ARRLEN(iv));
if(rv != 0) {
rv = nghttp2_submit_settings(session_data->session, NGHTTP2_FLAG_NONE, iv,
ARRLEN(iv));
if (rv != 0) {
errx(1, "Could not submit SETTINGS: %s", nghttp2_strerror(rv));
}
}
@ -225,24 +215,22 @@ used, which is described about later.
After the transmission of client connection header, we enqueue HTTP
request in ``submit_request()`` function::
static void submit_request(http2_session_data *session_data)
{
static void submit_request(http2_session_data *session_data) {
int32_t stream_id;
http2_stream_data *stream_data = session_data->stream_data;
const char *uri = stream_data->uri;
const struct http_parser_url *u = stream_data->u;
nghttp2_nv hdrs[] = {
MAKE_NV2(":method", "GET"),
MAKE_NV(":scheme",
&uri[u->field_data[UF_SCHEMA].off], u->field_data[UF_SCHEMA].len),
MAKE_NV(":authority", stream_data->authority, stream_data->authoritylen),
MAKE_NV(":path", stream_data->path, stream_data->pathlen)
};
MAKE_NV2(":method", "GET"),
MAKE_NV(":scheme", &uri[u->field_data[UF_SCHEMA].off],
u->field_data[UF_SCHEMA].len),
MAKE_NV(":authority", stream_data->authority, stream_data->authoritylen),
MAKE_NV(":path", stream_data->path, stream_data->pathlen)};
fprintf(stderr, "Request headers:\n");
print_headers(stderr, hdrs, ARRLEN(hdrs));
stream_id = nghttp2_submit_request(session_data->session, NULL,
hdrs, ARRLEN(hdrs), NULL, stream_data);
if(stream_id < 0) {
stream_id = nghttp2_submit_request(session_data->session, NULL, hdrs,
ARRLEN(hdrs), NULL, stream_data);
if (stream_id < 0) {
errx(1, "Could not submit HTTP request: %s", nghttp2_strerror(stream_id));
}
@ -261,26 +249,25 @@ this request.
The next bufferevent callback is ``readcb()``, which is invoked when
data is available to read in the bufferevent input buffer::
static void readcb(struct bufferevent *bev, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
static void readcb(struct bufferevent *bev, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
ssize_t readlen;
struct evbuffer *input = bufferevent_get_input(bev);
size_t datalen = evbuffer_get_length(input);
unsigned char *data = evbuffer_pullup(input, -1);
readlen = nghttp2_session_mem_recv(session_data->session, data, datalen);
if(readlen < 0) {
if (readlen < 0) {
warnx("Fatal error: %s", nghttp2_strerror((int)readlen));
delete_http2_session_data(session_data);
return;
}
if(evbuffer_drain(input, readlen) != 0) {
if (evbuffer_drain(input, readlen) != 0) {
warnx("Fatal error: evbuffer_drain failed");
delete_http2_session_data(session_data);
return;
}
if(session_send(session_data) != 0) {
if (session_send(session_data) != 0) {
delete_http2_session_data(session_data);
return;
}
@ -293,12 +280,11 @@ invoke nghttp2 callbacks and also queue frames. Since there may be
pending frames, we call ``session_send()`` function to send those
frames. The ``session_send()`` function is defined as follows::
static int session_send(http2_session_data *session_data)
{
static int session_send(http2_session_data *session_data) {
int rv;
rv = nghttp2_session_send(session_data->session);
if(rv != 0) {
if (rv != 0) {
warnx("Fatal error: %s", nghttp2_strerror(rv));
return -1;
}
@ -310,11 +296,9 @@ format and call ``send_callback()`` function of type
:type:`nghttp2_send_callback`. The ``send_callback()`` is defined as
follows::
static ssize_t send_callback(nghttp2_session *session,
const uint8_t *data, size_t length,
int flags, void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
static ssize_t send_callback(nghttp2_session *session _U_, const uint8_t *data,
size_t length, int flags _U_, void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
struct bufferevent *bev = session_data->bev;
bufferevent_write(bev, data, length);
return length;
@ -336,12 +320,11 @@ buffered data, see the ``send_callback()`` in the server tutorial.
The third bufferevent callback is ``writecb()``, which is invoked when
all data written in the bufferevent output buffer have been sent::
static void writecb(struct bufferevent *bev, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
if(nghttp2_session_want_read(session_data->session) == 0 &&
nghttp2_session_want_write(session_data->session) == 0 &&
evbuffer_get_length(bufferevent_get_output(session_data->bev)) == 0) {
static void writecb(struct bufferevent *bev _U_, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
if (nghttp2_session_want_read(session_data->session) == 0 &&
nghttp2_session_want_write(session_data->session) == 0 &&
evbuffer_get_length(bufferevent_get_output(session_data->bev)) == 0) {
delete_http2_session_data(session_data);
}
}
@ -367,18 +350,16 @@ Let's describe remaining nghttp2 callbacks we setup in
Each request header name/value pair is emitted via
``on_header_callback`` function::
static int on_header_callback(nghttp2_session *session,
const nghttp2_frame *frame,
const uint8_t *name, size_t namelen,
const uint8_t *value, size_t valuelen,
uint8_t flags,
void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
switch(frame->hd.type) {
static int on_header_callback(nghttp2_session *session _U_,
const nghttp2_frame *frame, const uint8_t *name,
size_t namelen, const uint8_t *value,
size_t valuelen, uint8_t flags _U_,
void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
switch (frame->hd.type) {
case NGHTTP2_HEADERS:
if(frame->headers.cat == NGHTTP2_HCAT_RESPONSE &&
session_data->stream_data->stream_id == frame->hd.stream_id) {
if (frame->headers.cat == NGHTTP2_HCAT_RESPONSE &&
session_data->stream_data->stream_id == frame->hd.stream_id) {
/* Print response headers for the initiated request. */
print_header(stderr, name, namelen, value, valuelen);
break;
@ -392,14 +373,13 @@ In this tutorial, we just print the name/value pair.
After all name/value pairs are emitted for a frame,
``on_frame_recv_callback`` function is called::
static int on_frame_recv_callback(nghttp2_session *session,
const nghttp2_frame *frame, void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
switch(frame->hd.type) {
static int on_frame_recv_callback(nghttp2_session *session _U_,
const nghttp2_frame *frame, void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
switch (frame->hd.type) {
case NGHTTP2_HEADERS:
if(frame->headers.cat == NGHTTP2_HCAT_RESPONSE &&
session_data->stream_data->stream_id == frame->hd.stream_id) {
if (frame->headers.cat == NGHTTP2_HCAT_RESPONSE &&
session_data->stream_data->stream_id == frame->hd.stream_id) {
fprintf(stderr, "All headers received\n");
}
break;
@ -415,13 +395,12 @@ its stream ID.
The ``on_data_chunk_recv_callback()`` function is invoked when a chunk
of data is received from the remote peer::
static int on_data_chunk_recv_callback(nghttp2_session *session, uint8_t flags,
int32_t stream_id,
static int on_data_chunk_recv_callback(nghttp2_session *session _U_,
uint8_t flags _U_, int32_t stream_id,
const uint8_t *data, size_t len,
void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
if(session_data->stream_data->stream_id == stream_id) {
void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
if (session_data->stream_data->stream_id == stream_id) {
fwrite(data, len, 1, stdout);
}
return 0;
@ -435,19 +414,17 @@ some binary data.
The ``on_stream_close_callback()`` function is invoked when the stream
is about to close::
static int on_stream_close_callback(nghttp2_session *session,
int32_t stream_id,
static int on_stream_close_callback(nghttp2_session *session, int32_t stream_id,
nghttp2_error_code error_code,
void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
int rv;
if(session_data->stream_data->stream_id == stream_id) {
fprintf(stderr, "Stream %d closed with error_code=%d\n",
stream_id, error_code);
if (session_data->stream_data->stream_id == stream_id) {
fprintf(stderr, "Stream %d closed with error_code=%d\n", stream_id,
error_code);
rv = nghttp2_session_terminate_session(session, NGHTTP2_NO_ERROR);
if(rv != 0) {
if (rv != 0) {
return NGHTTP2_ERR_CALLBACK_FAILURE;
}
}

View File

@ -29,17 +29,17 @@ time::
static unsigned char next_proto_list[256];
static size_t next_proto_list_len;
static int next_proto_cb(SSL *s, const unsigned char **data, unsigned int *len,
void *arg)
{
static int next_proto_cb(SSL *s _U_, const unsigned char **data,
unsigned int *len, void *arg _U_) {
*data = next_proto_list;
*len = (unsigned int)next_proto_list_len;
return SSL_TLSEXT_ERR_OK;
}
static SSL_CTX* create_ssl_ctx(const char *key_file, const char *cert_file)
{
static SSL_CTX *create_ssl_ctx(const char *key_file, const char *cert_file) {
SSL_CTX *ssl_ctx;
EC_KEY *ecdh;
ssl_ctx = SSL_CTX_new(SSLv23_server_method());
...
@ -104,8 +104,7 @@ We first create a listener object to accept incoming connections. We use
libevent's ``struct evconnlistener`` for this purpose::
static void start_listen(struct event_base *evbase, const char *service,
app_context *app_ctx)
{
app_context *app_ctx) {
int rv;
struct addrinfo hints;
struct addrinfo *res, *rp;
@ -116,19 +115,20 @@ libevent's ``struct evconnlistener`` for this purpose::
hints.ai_flags = AI_PASSIVE;
#ifdef AI_ADDRCONFIG
hints.ai_flags |= AI_ADDRCONFIG;
#endif // AI_ADDRCONFIG
#endif /* AI_ADDRCONFIG */
rv = getaddrinfo(NULL, service, &hints, &res);
if(rv != 0) {
if (rv != 0) {
errx(1, NULL);
}
for(rp = res; rp; rp = rp->ai_next) {
for (rp = res; rp; rp = rp->ai_next) {
struct evconnlistener *listener;
listener = evconnlistener_new_bind(evbase, acceptcb, app_ctx,
LEV_OPT_CLOSE_ON_FREE |
LEV_OPT_REUSEABLE, -1,
rp->ai_addr, rp->ai_addrlen);
if(listener) {
listener = evconnlistener_new_bind(
evbase, acceptcb, app_ctx, LEV_OPT_CLOSE_ON_FREE | LEV_OPT_REUSEABLE,
16, rp->ai_addr, rp->ai_addrlen);
if (listener) {
freeaddrinfo(res);
return;
}
}
@ -138,10 +138,9 @@ libevent's ``struct evconnlistener`` for this purpose::
We specify the ``acceptcb`` callback which is called when a new connection is
accepted::
static void acceptcb(struct evconnlistener *listener, int fd,
struct sockaddr *addr, int addrlen, void *arg)
{
app_context *app_ctx = (app_context*)arg;
static void acceptcb(struct evconnlistener *listener _U_, int fd,
struct sockaddr *addr, int addrlen, void *arg) {
app_context *app_ctx = (app_context *)arg;
http2_session_data *session_data;
session_data = create_http2_session_data(app_ctx, fd, addr, addrlen);
@ -158,26 +157,25 @@ The ``eventcb()`` callback is invoked by the libevent event loop when an event
(e.g., connection has been established, timeout, etc) happens on the
underlying network socket::
static void eventcb(struct bufferevent *bev, short events, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
if(events & BEV_EVENT_CONNECTED) {
static void eventcb(struct bufferevent *bev _U_, short events, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
if (events & BEV_EVENT_CONNECTED) {
fprintf(stderr, "%s connected\n", session_data->client_addr);
initialize_nghttp2_session(session_data);
if(send_server_connection_header(session_data) != 0) {
if (send_server_connection_header(session_data) != 0) {
delete_http2_session_data(session_data);
return;
}
return;
}
if(events & BEV_EVENT_EOF) {
if (events & BEV_EVENT_EOF) {
fprintf(stderr, "%s EOF\n", session_data->client_addr);
} else if(events & BEV_EVENT_ERROR) {
} else if (events & BEV_EVENT_ERROR) {
fprintf(stderr, "%s network error\n", session_data->client_addr);
} else if(events & BEV_EVENT_TIMEOUT) {
} else if (events & BEV_EVENT_TIMEOUT) {
fprintf(stderr, "%s timeout\n", session_data->client_addr);
}
delete_http2_session_data(session_data);
@ -195,8 +193,7 @@ communication.
We initialize a nghttp2 session object which is done in
``initialize_nghttp2_session()``::
static void initialize_nghttp2_session(http2_session_data *session_data)
{
static void initialize_nghttp2_session(http2_session_data *session_data) {
nghttp2_option *option;
nghttp2_session_callbacks *callbacks;
@ -210,19 +207,17 @@ We initialize a nghttp2 session object which is done in
nghttp2_session_callbacks_set_send_callback(callbacks, send_callback);
nghttp2_session_callbacks_set_on_frame_recv_callback
(callbacks, on_frame_recv_callback);
nghttp2_session_callbacks_set_on_frame_recv_callback(callbacks,
on_frame_recv_callback);
nghttp2_session_callbacks_set_on_stream_close_callback
(callbacks, on_stream_close_callback);
nghttp2_session_callbacks_set_on_header_callback
(callbacks, on_header_callback);
nghttp2_session_callbacks_set_on_begin_headers_callback
(callbacks, on_begin_headers_callback);
nghttp2_session_callbacks_set_on_stream_close_callback(
callbacks, on_stream_close_callback);
nghttp2_session_callbacks_set_on_header_callback(callbacks,
on_header_callback);
nghttp2_session_callbacks_set_on_begin_headers_callback(
callbacks, on_begin_headers_callback);
nghttp2_session_server_new2(&session_data->session, callbacks, session_data,
option);
@ -242,16 +237,14 @@ saves some lines of application code.
After initialization of the nghttp2 session object, we are going to send
a server connection header in ``send_server_connection_header()``::
static int send_server_connection_header(http2_session_data *session_data)
{
static int send_server_connection_header(http2_session_data *session_data) {
nghttp2_settings_entry iv[1] = {
{ NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 100 }
};
{NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 100}};
int rv;
rv = nghttp2_submit_settings(session_data->session, NGHTTP2_FLAG_NONE,
iv, ARRLEN(iv));
if(rv != 0) {
rv = nghttp2_submit_settings(session_data->session, NGHTTP2_FLAG_NONE, iv,
ARRLEN(iv));
if (rv != 0) {
warnx("Fatal error: %s", nghttp2_strerror(rv));
return -1;
}
@ -272,23 +265,22 @@ have to process them here since libevent won't invoke callback functions for
this pending data. To process the received data, we call the
``session_recv()`` function::
static int session_recv(http2_session_data *session_data)
{
static int session_recv(http2_session_data *session_data) {
ssize_t readlen;
struct evbuffer *input = bufferevent_get_input(session_data->bev);
size_t datalen = evbuffer_get_length(input);
unsigned char *data = evbuffer_pullup(input, -1);
readlen = nghttp2_session_mem_recv(session_data->session, data, datalen);
if(readlen < 0) {
if (readlen < 0) {
warnx("Fatal error: %s", nghttp2_strerror((int)readlen));
return -1;
}
if(evbuffer_drain(input, readlen) != 0) {
if (evbuffer_drain(input, readlen) != 0) {
warnx("Fatal error: evbuffer_drain failed");
return -1;
}
if(session_send(session_data) != 0) {
if (session_send(session_data) != 0) {
return -1;
}
return 0;
@ -301,11 +293,10 @@ nghttp2 callbacks and also queue outgoing frames. Since there may be pending
outgoing frames, we call ``session_send()`` function to send off those
frames. The ``session_send()`` function is defined as follows::
static int session_send(http2_session_data *session_data)
{
static int session_send(http2_session_data *session_data) {
int rv;
rv = nghttp2_session_send(session_data->session);
if(rv != 0) {
if (rv != 0) {
warnx("Fatal error: %s", nghttp2_strerror(rv));
return -1;
}
@ -317,15 +308,13 @@ format and calls ``send_callback()`` of type
:type:`nghttp2_send_callback`. The ``send_callback()`` is defined as
follows::
static ssize_t send_callback(nghttp2_session *session,
const uint8_t *data, size_t length,
int flags, void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
static ssize_t send_callback(nghttp2_session *session _U_, const uint8_t *data,
size_t length, int flags _U_, void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
struct bufferevent *bev = session_data->bev;
/* Avoid excessive buffering in server side. */
if(evbuffer_get_length(bufferevent_get_output(session_data->bev)) >=
OUTPUT_WOULDBLOCK_THRESHOLD) {
if (evbuffer_get_length(bufferevent_get_output(session_data->bev)) >=
OUTPUT_WOULDBLOCK_THRESHOLD) {
return NGHTTP2_ERR_WOULDBLOCK;
}
bufferevent_write(bev, data, length);
@ -350,10 +339,9 @@ calling send_callback.
The next bufferevent callback is ``readcb()``, which is invoked when
data is available to read in the bufferevent input buffer::
static void readcb(struct bufferevent *bev, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
if(session_recv(session_data) != 0) {
static void readcb(struct bufferevent *bev _U_, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
if (session_recv(session_data) != 0) {
delete_http2_session_data(session_data);
return;
}
@ -365,18 +353,17 @@ data.
The third bufferevent callback is ``writecb()``, which is invoked when all
data in the bufferevent output buffer has been sent::
static void writecb(struct bufferevent *bev, void *ptr)
{
http2_session_data *session_data = (http2_session_data*)ptr;
if(evbuffer_get_length(bufferevent_get_output(bev)) > 0) {
static void writecb(struct bufferevent *bev, void *ptr) {
http2_session_data *session_data = (http2_session_data *)ptr;
if (evbuffer_get_length(bufferevent_get_output(bev)) > 0) {
return;
}
if(nghttp2_session_want_read(session_data->session) == 0 &&
nghttp2_session_want_write(session_data->session) == 0) {
if (nghttp2_session_want_read(session_data->session) == 0 &&
nghttp2_session_want_write(session_data->session) == 0) {
delete_http2_session_data(session_data);
return;
}
if(session_send(session_data) != 0) {
if (session_send(session_data) != 0) {
delete_http2_session_data(session_data);
return;
}
@ -407,13 +394,12 @@ a header block in HEADERS or PUSH_PROMISE frame is started::
static int on_begin_headers_callback(nghttp2_session *session,
const nghttp2_frame *frame,
void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
http2_stream_data *stream_data;
if(frame->hd.type != NGHTTP2_HEADERS ||
frame->headers.cat != NGHTTP2_HCAT_REQUEST) {
if (frame->hd.type != NGHTTP2_HEADERS ||
frame->headers.cat != NGHTTP2_HCAT_REQUEST) {
return 0;
}
stream_data = create_http2_stream_data(session_data, frame->hd.stream_id);
@ -436,26 +422,26 @@ emitted via ``on_header_callback`` function, which is called after
``on_begin_headers_callback()``::
static int on_header_callback(nghttp2_session *session,
const nghttp2_frame *frame,
const uint8_t *name, size_t namelen,
const uint8_t *value, size_t valuelen,
void *user_data)
{
const nghttp2_frame *frame, const uint8_t *name,
size_t namelen, const uint8_t *value,
size_t valuelen, uint8_t flags _U_,
void *user_data _U_) {
http2_stream_data *stream_data;
const char PATH[] = ":path";
switch(frame->hd.type) {
switch (frame->hd.type) {
case NGHTTP2_HEADERS:
if(frame->headers.cat != NGHTTP2_HCAT_REQUEST) {
if (frame->headers.cat != NGHTTP2_HCAT_REQUEST) {
break;
}
stream_data = nghttp2_session_get_stream_user_data(session,
frame->hd.stream_id);
if(!stream_data || stream_data->request_path) {
stream_data =
nghttp2_session_get_stream_user_data(session, frame->hd.stream_id);
if (!stream_data || stream_data->request_path) {
break;
}
if(namelen == sizeof(PATH) - 1 && memcmp(PATH, name, namelen) == 0) {
if (namelen == sizeof(PATH) - 1 && memcmp(PATH, name, namelen) == 0) {
size_t j;
for(j = 0; j < valuelen && value[j] != '?'; ++j);
for (j = 0; j < valuelen && value[j] != '?'; ++j)
;
stream_data->request_path = percent_decode(value, j);
}
break;
@ -472,20 +458,19 @@ The ``on_frame_recv_callback()`` function is invoked when a frame is
fully received::
static int on_frame_recv_callback(nghttp2_session *session,
const nghttp2_frame *frame, void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
const nghttp2_frame *frame, void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
http2_stream_data *stream_data;
switch(frame->hd.type) {
switch (frame->hd.type) {
case NGHTTP2_DATA:
case NGHTTP2_HEADERS:
/* Check that the client request has finished */
if(frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
stream_data = nghttp2_session_get_stream_user_data(session,
frame->hd.stream_id);
if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
stream_data =
nghttp2_session_get_stream_user_data(session, frame->hd.stream_id);
/* For DATA and HEADERS frame, this callback may be called after
on_stream_close_callback. Check that stream still alive. */
if(!stream_data) {
if (!stream_data) {
return 0;
}
return on_request_recv(session, session_data, stream_data);
@ -508,15 +493,14 @@ header.
Sending the content of the file is done in ``send_response()`` function::
static int send_response(nghttp2_session *session, int32_t stream_id,
nghttp2_nv *nva, size_t nvlen, int fd)
{
nghttp2_nv *nva, size_t nvlen, int fd) {
int rv;
nghttp2_data_provider data_prd;
data_prd.source.fd = fd;
data_prd.read_callback = file_read_callback;
rv = nghttp2_submit_response(session, stream_id, nva, nvlen, &data_prd);
if(rv != 0) {
if (rv != 0) {
warnx("Fatal error: %s", nghttp2_strerror(rv));
return -1;
}
@ -530,18 +514,19 @@ intended to be used as file descriptor. In this example server, we use
the file descriptor. We also set the ``file_read_callback()`` callback
function to read the contents of the file::
static ssize_t file_read_callback
(nghttp2_session *session, int32_t stream_id,
uint8_t *buf, size_t length, uint32_t *data_flags,
nghttp2_data_source *source, void *user_data)
{
static ssize_t file_read_callback(nghttp2_session *session _U_,
int32_t stream_id _U_, uint8_t *buf,
size_t length, uint32_t *data_flags,
nghttp2_data_source *source,
void *user_data _U_) {
int fd = source->fd;
ssize_t r;
while((r = read(fd, buf, length)) == -1 && errno == EINTR);
if(r == -1) {
while ((r = read(fd, buf, length)) == -1 && errno == EINTR)
;
if (r == -1) {
return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
}
if(r == 0) {
if (r == 0) {
*data_flags |= NGHTTP2_DATA_FLAG_EOF;
}
return r;
@ -559,16 +544,13 @@ remote peer.
The ``on_stream_close_callback()`` function is invoked when the stream
is about to close::
static int on_stream_close_callback(nghttp2_session *session,
int32_t stream_id,
nghttp2_error_code error_code,
void *user_data)
{
http2_session_data *session_data = (http2_session_data*)user_data;
static int on_stream_close_callback(nghttp2_session *session, int32_t stream_id,
uint32_t error_code _U_, void *user_data) {
http2_session_data *session_data = (http2_session_data *)user_data;
http2_stream_data *stream_data;
stream_data = nghttp2_session_get_stream_user_data(session, stream_id);
if(!stream_data) {
if (!stream_data) {
return 0;
}
remove_stream(session_data, stream_data);