From 5b00b6a64fb75cdfad2c5f98571c450378700bf5 Mon Sep 17 00:00:00 2001
From: Ryan Dahl <ry@tinyclouds.org>
Date: Fri, 20 Nov 2009 15:36:55 +0100
Subject: [PATCH] add http_should_keep_alive()

---
 http_parser.c | 63 +++++++++++++++++++++++++++++++--------------------
 http_parser.h |  6 +++++
 test.c        |  4 ++--
 3 files changed, 47 insertions(+), 26 deletions(-)

diff --git a/http_parser.c b/http_parser.c
index 7362c24..e4948f7 100644
--- a/http_parser.c
+++ b/http_parser.c
@@ -146,7 +146,9 @@ static const uint32_t  usual[] = {
 };
 
 enum state 
-  { s_start_res = 1 /* important that this is > 0 */
+  { s_dead = 1 /* important that this is > 0 */
+
+  , s_start_res
   , s_res_H
   , s_res_HT
   , s_res_HTT
@@ -289,6 +291,12 @@ size_t parse (http_parser *parser, const char *data, size_t len, int start_state
     ch = *p;
     switch (state) {
 
+      case s_dead:
+        /* this state is used after a 'Connection: close' message
+         * the parser will error out if it reads another message
+         */
+        return 0;
+
       case s_start_res:
       {
         parser->flags = 0;
@@ -1241,7 +1249,7 @@ size_t parse (http_parser *parser, const char *data, size_t len, int start_state
         if (parser->flags & F_TRAILING) {
           /* End of a chunked request */
           CALLBACK2(message_complete);
-          state = start_state;
+          state = http_should_keep_alive(parser) ? start_state : s_dead;
           break;
         }
 
@@ -1256,32 +1264,18 @@ size_t parse (http_parser *parser, const char *data, size_t len, int start_state
           if (parser->content_length == 0) {
             /* Content-Length header given but zero: Content-Length: 0\r\n */
             CALLBACK2(message_complete);
-            state = start_state;
+            state = http_should_keep_alive(parser) ? start_state : s_dead;
           } else if (parser->content_length > 0) {
             /* Content-Length header given and non-zero */
             state = s_body_identity;
           } else {
-            /* No Content-Length header, not chunked */ 
-            if (parser->http_major > 0 && parser->http_minor > 0) {
-              /* HTTP/1.0 or HTTP/1.1 */
-              if (parser->flags & F_CONNECTION_CLOSE) {
-                /* Read body until EOF */
-                state = s_body_identity_eof;
-              } else {
-                /* Message is done - read the next */
-                CALLBACK2(message_complete);
-                state = start_state;
-              }
+            if (http_should_keep_alive(parser)) {
+              /* Assume content-length 0 - read the next */
+              CALLBACK2(message_complete);
+              state = start_state;
             } else {
-              /* HTTP/1.0 or earlier */
-              if (parser->flags & F_CONNECTION_KEEP_ALIVE) {
-                /* Message is done - read the next */
-                CALLBACK2(message_complete);
-                state = start_state;
-              } else {
-                /* Read body until EOF */
-                state = s_body_identity_eof;
-              }
+              /* Read body until EOF */
+              state = s_body_identity_eof;
             }
           }
         }
@@ -1297,7 +1291,7 @@ size_t parse (http_parser *parser, const char *data, size_t len, int start_state
           parser->body_read += to_read;
           if (parser->body_read == parser->content_length) {
             CALLBACK2(message_complete);
-            state = start_state;
+            state = http_should_keep_alive(parser) ? start_state : s_dead;
           }
         }
         break;
@@ -1440,6 +1434,27 @@ http_parse_responses (http_parser *parser, const char *data, size_t len)
 }
 
 
+int
+http_should_keep_alive (http_parser *parser)
+{
+  if (parser->http_major > 0 && parser->http_minor > 0) {
+    /* HTTP/1.1 */
+    if (parser->flags & F_CONNECTION_CLOSE) {
+      return 0;
+    } else {
+      return 1;
+    }
+  } else {
+    /* HTTP/1.0 or earlier */
+    if (parser->flags & F_CONNECTION_KEEP_ALIVE) {
+      return 1;
+    } else {
+      return 0;
+    }
+  }
+}
+
+
 void
 http_parser_init (http_parser *parser)
 {
diff --git a/http_parser.h b/http_parser.h
index eaca330..d27c068 100644
--- a/http_parser.h
+++ b/http_parser.h
@@ -112,6 +112,12 @@ struct http_parser {
 void http_parser_init(http_parser *parser);
 size_t http_parse_requests(http_parser *parser, const char *data, size_t len);
 size_t http_parse_responses(http_parser *parser, const char *data, size_t len);
+/* Call this in the on_headers_complete or on_message_complete callback to
+ * determine if this will be the last message on the connection.  
+ * If you are the server, respond with the "Connection: close" header
+ * if you are the client, close the connection.
+ */
+int http_should_keep_alive(http_parser *parser);
 
 #ifdef __cplusplus
 }
diff --git a/test.c b/test.c
index 62fe943..8658235 100644
--- a/test.c
+++ b/test.c
@@ -1085,9 +1085,9 @@ main (void)
            );
 
   printf("request scan 2/3      ");
-  test_scan( &requests[GET_FUNKY_CONTENT_LENGTH]
+  test_scan( &requests[POST_CHUNKED_ALL_YOUR_BASE]
            , &requests[POST_IDENTITY_BODY_WORLD]
-           , &requests[POST_CHUNKED_ALL_YOUR_BASE]
+           , &requests[GET_FUNKY_CONTENT_LENGTH]
            );
 
   printf("request scan 3/3      ");