Turn FileDescriptorInfo a collection class

content/browser/zygote_host/zygote_host_impl_linux.cc

Index: content/browser/zygote_host/zygote_host_impl_linux.cc
diff --git a/content/browser/zygote_host/zygote_host_impl_linux.cc b/content/browser/zygote_host/zygote_host_impl_linux.cc
index 0ead4ce1c33d9005adfed3a95abc88a823ec7b46..b30262a026ba9711eed9ae914808a3780468a271 100644
--- a/content/browser/zygote_host/zygote_host_impl_linux.cc
+++ b/content/browser/zygote_host/zygote_host_impl_linux.cc
@@ -287,10 +287,9 @@ ssize_t ZygoteHostImpl::ReadReply(void* buf, size_t buf_len) {
   return HANDLE_EINTR(read(control_fd_, buf, buf_len));
 }
 
-pid_t ZygoteHostImpl::ForkRequest(
-    const std::vector<std::string>& argv,
-    const std::vector<FileDescriptorInfo>& mapping,
-    const std::string& process_type) {
+pid_t ZygoteHostImpl::ForkRequest(const std::vector<std::string>& argv,
+                                  scoped_ptr<FileDescriptorInfo> mapping,
+                                  const std::string& process_type) {
   DCHECK(init_);
   Pickle pickle;
 
@@ -309,26 +308,17 @@ pid_t ZygoteHostImpl::ForkRequest(
 
   // Fork requests contain one file descriptor for the PID oracle, and one
   // more for each file descriptor mapping for the child process.
-  const size_t num_fds_to_send = 1 + mapping.size();
+  const size_t num_fds_to_send = 1 + mapping->size();
   pickle.WriteInt(num_fds_to_send);
 
   std::vector<int> fds;
-  ScopedVector<base::ScopedFD> autoclose_fds;
 
   // First FD to send is peer_sock.
   fds.push_back(peer_sock.get());
-  autoclose_fds.push_back(new base::ScopedFD(peer_sock.Pass()));
-
   // The rest come from mapping.
-  for (std::vector<FileDescriptorInfo>::const_iterator
-       i = mapping.begin(); i != mapping.end(); ++i) {
-    pickle.WriteUInt32(i->id);
-    fds.push_back(i->fd.fd);
-    if (i->fd.auto_close) {
-      // Auto-close means we need to close the FDs after they have been passed
-      // to the other process.
-      autoclose_fds.push_back(new base::ScopedFD(i->fd.fd));
-    }
+  for (size_t i = 0; i < mapping->size(); ++i) {
+    pickle.WriteUInt32(mapping->GetIDAt(i));
+    fds.push_back(mapping->GetFDAt(i));
   }
 
   // Sanity check that we've populated |fds| correctly.
@@ -339,7 +329,8 @@ pid_t ZygoteHostImpl::ForkRequest(
     base::AutoLock lock(control_lock_);
     if (!SendMessage(pickle, &fds))
       return base::kNullProcessHandle;
-    autoclose_fds.clear();
+    peer_sock.reset();
+    mapping.reset();

[jln (very slow on Chromium), 2014/09/22 17:54:15]

I find this slightly worse. Having one autoclose_fds variable made it easier to
know what we close.

[mdempsky, 2014/09/22 18:30:51]

Agreed, though it's overall fewer lines of code, so I'm okay with it as a
net-win towards simplicity.

[Hajime Morrita, 2014/09/22 22:59:26]

Let me have some addition to FileDescriptorInfo to simplify this.

 
     {
       char buf[sizeof(kZygoteChildPingMessage) + 1];