commit 50d4c71c942c1c4b9c54412507301a5f6630d74b
author wub <wub@google.com> Tue May 19 15:48:28 2020 -0700
committer Copybara-Service <copybara-worker@google.com> Tue May 19 15:49:01 2020 -0700
tree 0bf3a48c89d03f7d21c16ea10ca64f80e720b3e2
parent 403342681c37abe75ccb866418dd6cd23eac35d8

Change quicpacketwriter::getnextwritelocation to return a release function used to free a writer-allocated buffer. use this release function to avoid buffer leak if a writer buffer is allocated but writer->writepacket is not called. protected by --gfe2_reloadable_flag_quic_avoid_leak_writer_buffer.

This is needed to fix a buffer leak when the new PigeonWriter is used.

PiperOrigin-RevId: 312369772
Change-Id: I0d12327b58989ec69e401b03f7b9ebb4d8ce22fd

quic/core/quic_packet_writer.h

diff --git a/quic/core/quic_packet_writer.h b/quic/core/quic_packet_writer.h
index ab29e15..6efdb60 100644
--- a/quic/core/quic_packet_writer.h
+++ b/quic/core/quic_packet_writer.h
@@ -125,17 +125,22 @@
   // True=Batch mode. False=PassThrough mode.
   virtual bool IsBatchMode() const = 0;
 
-  // PassThrough mode: Return nullptr.
+  // PassThrough mode: Return {nullptr, nullptr}
   //
   // Batch mode:
-  // Return the starting address for the next packet's data. A minimum of
+  // Return the QuicPacketBuffer for the next packet. A minimum of
   // kMaxOutgoingPacketSize is guaranteed to be available from the returned
-  // address. If the internal buffer does not have enough space, nullptr is
-  // returned. All arguments should be identical to the follow-up call to
-  // |WritePacket|, they are here to allow advanced packet memory management in
-  // packet writers, e.g. one packet buffer pool per |peer_address|.
-  virtual char* GetNextWriteLocation(const QuicIpAddress& self_address,
-                                     const QuicSocketAddress& peer_address) = 0;
+  // address. If the internal buffer does not have enough space,
+  // {nullptr, nullptr} is returned. All arguments should be identical to the
+  // follow-up call to |WritePacket|, they are here to allow advanced packet
+  // memory management in packet writers, e.g. one packet buffer pool per
+  // |peer_address|.
+  //
+  // If QuicPacketBuffer.release_buffer is !nullptr, it should be called iff
+  // the caller does not call WritePacket for the returned buffer.
+  virtual QuicPacketBuffer GetNextWriteLocation(
+      const QuicIpAddress& self_address,
+      const QuicSocketAddress& peer_address) = 0;
 
   // PassThrough mode: Return WriteResult(WRITE_STATUS_OK, 0).
   //