Increase MessageAttachmentSet::kMaxDescriptorsPerMessage

ipc/ipc_channel_nacl.cc

Index: ipc/ipc_channel_nacl.cc
diff --git a/ipc/ipc_channel_nacl.cc b/ipc/ipc_channel_nacl.cc
index 53397f475240a776e48e74e028ab53e9b1701735..49ac1393af10891a79c181836b26551c63d23d1d 100644
--- a/ipc/ipc_channel_nacl.cc
+++ b/ipc/ipc_channel_nacl.cc
@@ -37,7 +37,7 @@ bool ReadDataOnReaderThread(int pipe, MessageContents* contents) {
     return false;
 
   contents->data.resize(Channel::kReadBufferSize);
-  contents->fds.resize(MessageAttachmentSet::kMaxDescriptorsPerMessage);
+  contents->fds.resize(NACL_ABI_IMC_DESC_MAX);

[dmichael (off chromium), 2015/03/12 22:07:16]

We want this number to be == kMaxDescriptorsPerMessage, right? Is it possible to
have a static_assert here so we know if one of them changes?

[Yusuke Sato, 2015/03/12 22:19:28]

NACL_ABI_IMC_DESC_MAX defined in native_client/ is currently very small (8,
IIRC) and I think that's okay.

My understanding is that NACL_ABI_IPC_DESC_MAX defines the maximum number of FDs
that can be passed with one message from trusted to untrusted. Since there is no
IRT at this point that requires the trusted side to pass a large number of FDs
at once, I think keeping NACL_ABI_IMC_DESC_MAX small makes sense.

 
   NaClAbiNaClImcMsgIoVec iov = { &contents->data[0], contents->data.size() };
   NaClAbiNaClImcMsgHdr msg = {