http2: Use std::array for indexing headers

src/HttpServer.h

@@ -84,7 +84,7 @@ struct Stream {
   int64_t upload_left;
   int32_t stream_id;
   int file;
-  int hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex hdidx;
   Stream(Http2Handler *handler, int32_t stream_id);
   ~Stream();
 };

src/http2.cc

@@ -593,9 +593,11 @@ int lookup_token(const uint8_t *name, size_t namelen) {
   return -1;
 }
 
-void init_hdidx(int *hdidx) { memset(hdidx, -1, sizeof(hdidx[0]) * HD_MAXIDX); }
+void init_hdidx(HeaderIndex &hdidx) {
+  std::fill(std::begin(hdidx), std::end(hdidx), -1);
+}
 
-void index_headers(int *hdidx, const Headers &headers) {
+void index_headers(HeaderIndex &hdidx, const Headers &headers) {
   for (size_t i = 0; i < headers.size(); ++i) {
     auto &kv = headers[i];
     auto token = lookup_token(
@@ -606,7 +608,7 @@ void index_headers(int *hdidx, const Headers &headers) {
   }
 }
 
-void index_header(int *hdidx, int token, size_t idx) {
+void index_header(HeaderIndex &hdidx, int token, size_t idx) {
   if (token == -1) {
     return;
   }
@@ -614,7 +616,7 @@ void index_header(int *hdidx, int token, size_t idx) {
   hdidx[token] = idx;
 }
 
-bool check_http2_request_pseudo_header(const int *hdidx, int token) {
+bool check_http2_request_pseudo_header(const HeaderIndex &hdidx, int token) {
   switch (token) {
   case HD__AUTHORITY:
   case HD__METHOD:
@@ -626,7 +628,7 @@ bool check_http2_request_pseudo_header(const int *hdidx, int token) {
   }
 }
 
-bool check_http2_response_pseudo_header(const int *hdidx, int token) {
+bool check_http2_response_pseudo_header(const HeaderIndex &hdidx, int token) {
   switch (token) {
   case HD__STATUS:
     return hdidx[token] == -1;
@@ -648,7 +650,7 @@ bool http2_header_allowed(int token) {
   }
 }
 
-bool http2_mandatory_request_headers_presence(const int *hdidx) {
+bool http2_mandatory_request_headers_presence(const HeaderIndex &hdidx) {
   if (hdidx[HD__METHOD] == -1 || hdidx[HD__PATH] == -1 ||
       hdidx[HD__SCHEME] == -1 ||
       (hdidx[HD__AUTHORITY] == -1 && hdidx[HD_HOST] == -1)) {
@@ -657,7 +659,7 @@ bool http2_mandatory_request_headers_presence(const int *hdidx) {
   return true;
 }
 
-const Headers::value_type *get_header(const int *hdidx, int token,
+const Headers::value_type *get_header(const HeaderIndex &hdidx, int token,
                                       const Headers &nva) {
   auto i = hdidx[token];
   if (i == -1) {

src/http2.h

@@ -31,6 +31,7 @@
 #include <cstring>
 #include <string>
 #include <vector>
+#include <array>
 
 #include <nghttp2/nghttp2.h>
 
@@ -210,6 +211,8 @@ enum {
   HD_MAXIDX,
 };
 
+using HeaderIndex = std::array<int, HD_MAXIDX>;
+
 // Looks up header token for header name |name| of length |namelen|.
 // Only headers we are interested in are tokenized.  If header name
 // cannot be tokenized, returns -1.
@@ -218,19 +221,19 @@ int lookup_token(const std::string &name);
 
 // Initializes |hdidx|, header index.  The |hdidx| must point to the
 // array containing at least HD_MAXIDX elements.
-void init_hdidx(int *hdidx);
+void init_hdidx(HeaderIndex &hdidx);
 // Indexes header |token| using index |idx|.
-void index_header(int *hdidx, int token, size_t idx);
+void index_header(HeaderIndex &hdidx, int token, size_t idx);
 // Iterates |headers| and for each element, call index_header.
-void index_headers(int *hdidx, const Headers &headers);
+void index_headers(HeaderIndex &hdidx, const Headers &headers);
 
 // Returns true if HTTP/2 request pseudo header |token| is not indexed
 // yet and not -1.
-bool check_http2_request_pseudo_header(const int *hdidx, int token);
+bool check_http2_request_pseudo_header(const HeaderIndex &hdidx, int token);
 
 // Returns true if HTTP/2 response pseudo header |token| is not
 // indexed yet and not -1.
-bool check_http2_response_pseudo_header(const int *hdidx, int token);
+bool check_http2_response_pseudo_header(const HeaderIndex &hdidx, int token);
 
 // Returns true if header field denoted by |token| is allowed for
 // HTTP/2.
@@ -238,10 +241,10 @@ bool http2_header_allowed(int token);
 
 // Returns true that |hdidx| contains mandatory HTTP/2 request
 // headers.
-bool http2_mandatory_request_headers_presence(const int *hdidx);
+bool http2_mandatory_request_headers_presence(const HeaderIndex &hdidx);
 
 // Returns header denoted by |token| using index |hdidx|.
-const Headers::value_type *get_header(const int *hdidx, int token,
+const Headers::value_type *get_header(const HeaderIndex &hdidx, int token,
                                       const Headers &nva);
 
 } // namespace http2

src/http2_test.cc

@@ -120,7 +120,7 @@ void test_http2_get_header(void) {
   rv = http2::get_header(nva, "foxtrot");
   CU_ASSERT(rv == nullptr);
 
-  int hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex hdidx;
   http2::init_hdidx(hdidx);
   hdidx[http2::HD_CONTENT_LENGTH] = 6;
   rv = http2::get_header(hdidx, http2::HD_CONTENT_LENGTH, nva);
@@ -227,7 +227,7 @@ void test_http2_parse_http_status_code(void) {
 }
 
 void test_http2_index_header(void) {
-  int hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex hdidx;
   http2::init_hdidx(hdidx);
 
   http2::index_header(hdidx, http2::HD__AUTHORITY, 0);
@@ -244,7 +244,7 @@ void test_http2_lookup_token(void) {
 }
 
 void test_http2_check_http2_pseudo_header(void) {
-  int hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex hdidx;
   http2::init_hdidx(hdidx);
 
   CU_ASSERT(http2::check_http2_request_pseudo_header(hdidx, http2::HD__METHOD));
@@ -272,7 +272,7 @@ void test_http2_http2_header_allowed(void) {
 }
 
 void test_http2_mandatory_request_headers_presence(void) {
-  int hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex hdidx;
   http2::init_hdidx(hdidx);
 
   CU_ASSERT(!http2::http2_mandatory_request_headers_presence(hdidx));

src/nghttp.h

@@ -153,9 +153,9 @@ struct Request {
   int level;
   // RequestPriority value defined in HtmlParser.h
   int pri;
-  int res_hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex res_hdidx;
   // used for incoming PUSH_PROMISE
-  int req_hdidx[http2::HD_MAXIDX];
+  http2::HeaderIndex req_hdidx;
   bool expect_final_response;
 };
 

src/shrpx_downstream.cc

@@ -288,7 +288,8 @@ const std::string &Downstream::get_assembled_request_cookie() const {
 }
 
 namespace {
-int index_headers(int *hdidx, Headers &headers, int64_t &content_length) {
+int index_headers(http2::HeaderIndex &hdidx, Headers &headers,
+                  int64_t &content_length) {
   for (size_t i = 0; i < headers.size(); ++i) {
     auto &kv = headers[i];
     util::inp_strlower(kv.name);

src/shrpx_downstream.h

@@ -362,8 +362,8 @@ private:
   int response_major_;
   int response_minor_;
 
-  int request_hdidx_[http2::HD_MAXIDX];
-  int response_hdidx_[http2::HD_MAXIDX];
+  http2::HeaderIndex request_hdidx_;
+  http2::HeaderIndex response_hdidx_;
 
   // true if the request contains upgrade token (HTTP Upgrade or
   // CONNECT)