If a write is pending, just add it to the buffer. Don't trigger a second conc...

net/socket/ssl_client_socket_mac.cc

Index: net/socket/ssl_client_socket_mac.cc
===================================================================
--- net/socket/ssl_client_socket_mac.cc	(revision 21838)
+++ net/socket/ssl_client_socket_mac.cc	(working copy)
@@ -736,10 +736,21 @@
     return status;
   }
 
+  bool send_pending = !us->send_buffer_.empty();
+
   if (data)
     us->send_buffer_.insert(us->send_buffer_.end(),
                             static_cast<const char*>(data),
                             static_cast<const char*>(data) + *data_length);
+
+  if (send_pending) {
+    // If we have I/O in flight, just add the data to the end of the buffer and
+    // return to our caller. The existing callback will trigger the write of the
+    // new data when it sees that data remains in the buffer after removing the
+    // sent data.
+    return noErr;

[wtc, 2009/07/29 18:05:17]

Perhaps you can reproduce the "always lie to our caller"
comment here.  I wondered whether we should return noErr
or a would-block/io-pending error.

[Avi (use Gerrit), 2009/07/29 18:22:41]

Sure.

We can't return would-block. The caller wants to know how much is written and
we'd have no idea what to return.

+  }
+
   int rv;
   do {
     scoped_refptr<IOBuffer> buffer = new IOBuffer(us->send_buffer_.size());