Take the latency into account when evaluating whether or not to reuse a connection.
[privoxy.git] / parsers.c
index 687f2c2..ef0fde2 100644 (file)
--- a/parsers.c
+++ b/parsers.c
@@ -1,4 +1,4 @@
-const char parsers_rcs[] = "$Id: parsers.c,v 1.190 2009/07/05 20:43:14 ler762 Exp $";
+const char parsers_rcs[] = "$Id: parsers.c,v 1.196 2009/07/11 11:20:12 fabiankeil Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/parsers.c,v $
@@ -172,7 +172,6 @@ static jb_err create_forged_referrer(char **header, const char *hostport);
 static jb_err create_fake_referrer(char **header, const char *fake_referrer);
 static jb_err handle_conditional_hide_referrer_parameter(char **header,
    const char *host, const int parameter_conditional_block);
-static const char *get_appropiate_connection_header(const struct client_state *csp);
 static void create_content_length_header(unsigned long long content_length,
                                          char *header, size_t buffer_length);
 
@@ -1692,6 +1691,14 @@ static jb_err client_keep_alive(struct client_state *csp, char **header)
    unsigned int keep_alive_timeout;
    const char *timeout_position = strstr(*header, ": ");
 
+   if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
+   {
+      log_error(LOG_LEVEL_HEADER,
+         "keep-alive support is disabled. Crunching: %s.", *header);
+      freez(*header);
+      return JB_ERR_OK;
+   }
+
    if ((NULL == timeout_position)
     || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout)))
    {
@@ -1742,32 +1749,54 @@ static jb_err client_keep_alive(struct client_state *csp, char **header)
  *********************************************************************/
 static jb_err client_connection(struct client_state *csp, char **header)
 {
-   const char *wanted_header = get_appropiate_connection_header(csp);
+   static const char connection_close[] = "Connection: close";
 
-   if (strcmpic(*header, wanted_header))
+   if (!strcmpic(*header, connection_close))
    {
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
-      if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
+      if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
+      {
+          if (!strcmpic(csp->http->ver, "HTTP/1.1"))
+          {
+             log_error(LOG_LEVEL_HEADER,
+                "Removing \'%s\' to imply keep-alive.", *header);
+             freez(*header);
+          }
+          else
+          {
+             char *old_header = *header;
+
+             *header = strdup("Connection: keep-alive");
+             if (header == NULL)
+             {
+                return JB_ERR_MEMORY;
+             }
+             log_error(LOG_LEVEL_HEADER,
+                "Replaced: \'%s\' with \'%s\'", old_header, *header);
+             freez(old_header);
+          }
+          csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
+      }
+      else
       {
          log_error(LOG_LEVEL_HEADER,
             "Keeping the client header '%s' around. "
             "The connection will not be kept alive.",
             *header);
+         csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
       }
-      else
-#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
-      {
-         char *old_header = *header;
+#else
+      char *old_header = *header;
 
-         *header = strdup(wanted_header);
-         if (header == NULL)
-         {
-            return JB_ERR_MEMORY;
-         }
-         log_error(LOG_LEVEL_HEADER,
-            "Replaced: \'%s\' with \'%s\'", old_header, *header);
-         freez(old_header);
+      *header = strdup(connection_close);
+      if (header == NULL)
+      {
+         return JB_ERR_MEMORY;
       }
+      log_error(LOG_LEVEL_HEADER,
+         "Replaced: \'%s\' with \'%s\'", old_header, *header);
+      freez(old_header);
+#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
    }
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
    else
@@ -3448,7 +3477,7 @@ static jb_err server_connection_adder(struct client_state *csp)
 {
    const unsigned int flags = csp->flags;
    const char *response_status_line = csp->headers->first->str;
-   const char *wanted_header = get_appropiate_connection_header(csp);
+   static const char connection_close[] = "Connection: close";
 
    if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
     && (flags & CSP_FLAG_SERVER_CONNECTION_HEADER_SET))
@@ -3466,25 +3495,17 @@ static jb_err server_connection_adder(struct client_state *csp)
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
     && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
 #endif
-    && (csp->http->status == 200)
        )
    {
-      /*
-       * XXX: not doing this for status codes other than 200 works
-       * around problems with broken servers that will keep the
-       * connection open, but terminate the connection when the
-       * next request arrives. Once we are able to figure out which
-       * requests are safe to send again, this will probably no
-       * longer be necessary.
-       */
       log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
          "without Connection header implies keep-alive.");
       csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
+      return JB_ERR_OK;
    }
 
-   log_error(LOG_LEVEL_HEADER, "Adding: %s", wanted_header);
+   log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
 
-   return enlist(csp->headers, wanted_header);
+   return enlist(csp->headers, connection_close);
 }
 
 
@@ -3537,7 +3558,7 @@ static jb_err server_proxy_connection_adder(struct client_state *csp)
  *********************************************************************/
 static jb_err client_connection_header_adder(struct client_state *csp)
 {
-   const char *wanted_header = get_appropiate_connection_header(csp);
+   static const char connection_close[] = "Connection: close";
 
    if (!(csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
      && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET))
@@ -3551,12 +3572,13 @@ static jb_err client_connection_header_adder(struct client_state *csp)
       && !strcmpic(csp->http->ver, "HTTP/1.1"))
    {
       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
+      return JB_ERR_OK;
    }
 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
 
-   log_error(LOG_LEVEL_HEADER, "Adding: %s", wanted_header);
+   log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
 
-   return enlist(csp->headers, wanted_header);
+   return enlist(csp->headers, connection_close);
 }
 
 
@@ -4101,37 +4123,6 @@ static jb_err handle_conditional_hide_referrer_parameter(char **header,
 }
 
 
-/*********************************************************************
- *
- * Function    :  get_appropiate_connection_header
- *
- * Description :  Returns an appropiate Connection header
- *                depending on whether or not we try to keep
- *                the connection to the server alive.
- *
- * Parameters  :
- *          1  :  csp = Current client state (buffers, headers, etc...)
- *
- * Returns     :  Pointer to statically allocated header buffer.
- *
- *********************************************************************/
-static const char *get_appropiate_connection_header(const struct client_state *csp)
-{
-   static const char connection_keep_alive[] = "Connection: keep-alive";
-   static const char connection_close[] = "Connection: close";
-
-   if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
-#ifdef FEATURE_CONNECTION_KEEP_ALIVE
-    && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
-#endif
-    && (csp->http->ssl == 0))
-   {
-      return connection_keep_alive;
-   }
-   return connection_close;
-}
-
-
 /*********************************************************************
  *
  * Function    :  create_content_length_header