Basic HTTP pipelining support

net/http/http_network_transaction.cc

Index: net/http/http_network_transaction.cc
diff --git a/net/http/http_network_transaction.cc b/net/http/http_network_transaction.cc
index d1e7ec58ce8be7edcf9e90e220c5a878a6350ca5..f4218e8d7a53a72bc1adb3233ebaa6efdcae35a1 100644
--- a/net/http/http_network_transaction.cc
+++ b/net/http/http_network_transaction.cc
@@ -39,7 +39,6 @@
 #include "net/http/http_proxy_client_socket_pool.h"
 #include "net/http/http_request_headers.h"
 #include "net/http/http_request_info.h"
-#include "net/http/http_response_body_drainer.h"
 #include "net/http/http_response_headers.h"
 #include "net/http/http_response_info.h"
 #include "net/http/http_stream_factory.h"
@@ -135,15 +134,8 @@ HttpNetworkTransaction::~HttpNetworkTransaction() {
         stream_->Close(true /* not reusable */);
       } else {
         // Otherwise, we try to drain the response body.
-        // TODO(willchan): Consider moving this response body draining to the
-        // stream implementation.  For SPDY, there's clearly no point.  For
-        // HTTP, it can vary depending on whether or not we're pipelining.  It's
-        // stream dependent, so the different subtypes should be implementing
-        // their solutions.
-        HttpResponseBodyDrainer* drainer =
-          new HttpResponseBodyDrainer(stream_.release());
-        drainer->Start(session_);
-        // |drainer| will delete itself.
+        HttpStream* stream = stream_.release();
+        stream->Drain(session_);
       }
     }
   }
@@ -547,8 +539,6 @@ int HttpNetworkTransaction::DoLoop(int result) {
         break;
       case STATE_READ_HEADERS_COMPLETE:
         rv = DoReadHeadersComplete(rv);
-        net_log_.EndEventWithNetErrorCode(
-            NetLog::TYPE_HTTP_TRANSACTION_READ_HEADERS, rv);

[willchan no longer on Chromium, 2011/09/29 19:32:48]

You should keep this back where it was.

[James Simonsen, 2011/10/12 01:36:58]

Didn't mean to delete it. Forgot to save before uploading.

         break;
       case STATE_READ_BODY:
         DCHECK_EQ(OK, rv);
@@ -872,6 +862,10 @@ int HttpNetworkTransaction::DoReadHeadersComplete(int result) {
   if (is_https_request())
     stream_->GetSSLInfo(&response_.ssl_info);
 
+  if (read_buf_len_) {
+    next_state_ = STATE_READ_BODY;

[willchan no longer on Chromium, 2011/09/29 19:32:48]

I believe this is a bug. We should only transition to this state when Read() is
called.

[James Simonsen, 2011/10/12 01:36:58]

It's a tricky situation. Maybe I should just forget about it.

If we were to be evicted after Read() was called, then after restarting, we
shouldn't wait for Read() to be called again. We know Read() has been called if
we have a read_buf_len_.

Anyway, this shouldn't happen in practice, so I just removed it. I'd only seen
it while playing with the unit test.

[willchan no longer on Chromium, 2011/10/13 02:29:16]

A new test? Because this shouldn't happen, since no one is allowed to call
Read() until the response headers have been returned. If someone does this, they
are broken.

+  }
+
   headers_valid_ = true;
   return OK;
 }
@@ -1186,6 +1180,10 @@ int HttpNetworkTransaction::HandleIOError(int error) {
   error = HandleSSLHandshakeError(error);
 
   switch (error) {
+    case ERR_PIPELINE_EVICTION:

[willchan no longer on Chromium, 2011/09/29 19:32:48]

I think here you should log to net_log_. You should probably create a new event
for this. I think this event should also be logged below, above the call to 
ResetConnectionAndRequestForResend();

[James Simonsen, 2011/10/12 01:36:58]

Done.

+      error = RestartAfterPipelineEviction();
+      break;
+
     // If we try to reuse a connection that the server is in the process of
     // closing, we may end up successfully writing out our request (or a
     // portion of our request) only to find a connection error when we try to
@@ -1202,6 +1200,14 @@ int HttpNetworkTransaction::HandleIOError(int error) {
   return error;
 }
 
+int HttpNetworkTransaction::RestartAfterPipelineEviction() {
+  stream_->Close(true);
+  stream_.reset();
+  stream_request_.reset();
+  next_state_ = STATE_CREATE_STREAM;
+  return OK;
+}
+
 void HttpNetworkTransaction::ResetStateForRestart() {
   ResetStateForAuthRestart();
   stream_.reset();