Define magic descriptors in one place.

content/zygote/zygote_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/zygote/zygote_linux.h"
 
 #include <fcntl.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <sys/types.h>
@@ skipping 24 matching lines @@
 namespace content {
 
 namespace {
 
 // NOP function. See below where this handler is installed.
 void SIGCHLDHandler(int signal) {
 }
 
 }  // namespace
 
-const int Zygote::kMagicSandboxIPCDescriptor;
-
 Zygote::Zygote(int sandbox_flags,
                ZygoteForkDelegate* helper)
     : sandbox_flags_(sandbox_flags),
       helper_(helper),
       initial_uma_sample_(0),
       initial_uma_boundary_value_(0) {
   if (helper_) {
     helper_->InitialUMA(&initial_uma_name_,
                         &initial_uma_sample_,
                         &initial_uma_boundary_value_);
@@ skipping 13 matching lines @@
   // otherwise we cannot wait on children. (According to POSIX 2001.)
   struct sigaction action;
   memset(&action, 0, sizeof(action));
   action.sa_handler = &SIGCHLDHandler;
   CHECK(sigaction(SIGCHLD, &action, NULL) == 0);
 
   if (UsingSUIDSandbox()) {
     // Let the ZygoteHost know we are ready to go.
     // The receiving code is in content/browser/zygote_host_linux.cc.
     std::vector<int> empty;
-    bool r = UnixDomainSocket::SendMsg(kBrowserDescriptor,
+    bool r = UnixDomainSocket::SendMsg(kMagicZygoteDescriptor,
                                        kZygoteHelloMessage,
                                        sizeof(kZygoteHelloMessage), empty);
 #if defined(OS_CHROMEOS)
     LOG_IF(WARNING, !r) << "Sending zygote magic failed";
     // Exit normally on chromeos because session manager may send SIGTERM
     // right after the process starts and it may fail to send zygote magic
     // number to browser process.
     if (!r)
       _exit(RESULT_CODE_NORMAL_EXIT);
 #else
     CHECK(r) << "Sending zygote magic failed";
 #endif
   }
 
   for (;;) {
     // This function call can return multiple times, once per fork().
-    if (HandleRequestFromBrowser(kBrowserDescriptor))
+    if (HandleRequestFromBrowser(kMagicZygoteDescriptor))
       return true;
   }
 }
 
 bool Zygote::GetProcessInfo(base::ProcessHandle pid,
                             ZygoteProcessInfo* process_info) {
   DCHECK(process_info);
   const ZygoteProcessMap::const_iterator it = process_info_map_.find(pid);
   if (it == process_info_map_.end()) {
     return false;
@@ skipping 360 matching lines @@
   mapping.push_back(std::make_pair(
       static_cast<uint32_t>(kSandboxIPCChannel), kMagicSandboxIPCDescriptor));
 
   // Returns twice, once per process.
   base::ProcessId child_pid = ForkWithRealPid(process_type, fds, channel_id,
                                               uma_name, uma_sample,
                                               uma_boundary_value);
   if (!child_pid) {
     // This is the child process.
 
-    close(kBrowserDescriptor);  // Our socket from the browser.
+    close(kMagicZygoteDescriptor);  // Our socket from the browser.
     if (UsingSUIDSandbox())
       close(kZygoteIdFd);  // Another socket from the browser.
     base::GlobalDescriptors::GetInstance()->Reset(mapping);
 
     // Reset the process-wide command line to our new command line.
     CommandLine::Reset();
     CommandLine::Init(0, NULL);
     CommandLine::ForCurrentProcess()->InitFromArgv(args);
 
     // Update the process title. The argv was already cached by the call to
@@ skipping 50 matching lines @@
                                     PickleIterator iter) {
   if (HANDLE_EINTR(write(fd, &sandbox_flags_, sizeof(sandbox_flags_))) !=
                    sizeof(sandbox_flags_)) {
     PLOG(ERROR) << "write";
   }
 
   return false;
 }
 
 }  // namespace content