Refactor Pickle Read methods to use higher performance PickleIterator.

content/browser/zygote_host_impl_linux.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/zygote_host_impl_linux.h"
 
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
@@ skipping 260 matching lines @@
     if (!UnixDomainSocket::SendMsg(control_fd_, pickle.data(), pickle.size(),
                                    fds))
       return base::kNullProcessHandle;
 
     // Read the reply, which pickles the PID and an optional UMA enumeration.
     static const unsigned kMaxReplyLength = 2048;
     char buf[kMaxReplyLength];
     const ssize_t len = ReadReply(buf, sizeof(buf));
 
     Pickle reply_pickle(buf, len);
-    void* iter = NULL;
+    PickleIterator iter(reply_pickle);
     if (len <= 0 || !reply_pickle.ReadInt(&iter, &pid))
       return base::kNullProcessHandle;
 
     // If there is a nonempty UMA name string, then there is a UMA
     // enumeration to record.
     std::string uma_name;
     int uma_sample;
     int uma_boundary_value;
     if (reply_pickle.ReadString(&iter, &uma_name) &&
         !uma_name.empty() &&
@@ skipping 138 matching lines @@
   if (len == -1) {
     LOG(WARNING) << "Error reading message from zygote: " << errno;
     return base::TERMINATION_STATUS_NORMAL_TERMINATION;
   } else if (len == 0) {
     LOG(WARNING) << "Socket closed prematurely.";
     return base::TERMINATION_STATUS_NORMAL_TERMINATION;
   }
 
   Pickle read_pickle(buf, len);
   int status, tmp_exit_code;
-  void* iter = NULL;
+  PickleIterator iter(read_pickle);
   if (!read_pickle.ReadInt(&iter, &status) ||
       !read_pickle.ReadInt(&iter, &tmp_exit_code)) {
     LOG(WARNING) << "Error parsing GetTerminationStatus response from zygote.";
     return base::TERMINATION_STATUS_NORMAL_TERMINATION;
   }
 
   if (exit_code)
     *exit_code = tmp_exit_code;
 
   return static_cast<base::TerminationStatus>(status);
 }
 
 pid_t ZygoteHostImpl::GetPid() const {
   return pid_;
 }
 
 pid_t ZygoteHostImpl::GetSandboxHelperPid() const {
   return RenderSandboxHostLinux::GetInstance()->pid();
 }
 
 int ZygoteHostImpl::GetSandboxStatus() const {
   if (have_read_sandbox_status_word_)
     return sandbox_status_;
   return 0;
 }