Improve process launch handle sharing API.

components/nacl/zygote/nacl_fork_delegate_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 "components/nacl/zygote/nacl_fork_delegate_linux.h"
 
 #include <signal.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <sys/resource.h>
@@ skipping 156 matching lines @@
 
   // For communications between the NaCl loader process and
   // the browser process.
   int nacl_sandbox_descriptor =
       base::GlobalDescriptors::kBaseDescriptor + kSandboxIPCChannel;
   // Confirm a hard-wired assumption.
   DCHECK_EQ(sandboxdesc, nacl_sandbox_descriptor);
 
   int fds[2];
   PCHECK(0 == socketpair(PF_UNIX, SOCK_SEQPACKET, 0, fds));
-  base::FileHandleMappingVector fds_to_map;
-  fds_to_map.push_back(std::make_pair(fds[1], kNaClZygoteDescriptor));
-  fds_to_map.push_back(std::make_pair(sandboxdesc, nacl_sandbox_descriptor));
 
   bool use_nacl_bootstrap = false;
   // For non-SFI mode, we do not use fixed address space.
   if (!nonsfi_mode_) {
     // Using nacl_helper_bootstrap is not necessary on x86-64 because
     // NaCl's x86-64 sandbox is not zero-address-based.  Starting
     // nacl_helper through nacl_helper_bootstrap works on x86-64, but it
     // leaves nacl_helper_bootstrap mapped at a fixed address at the
     // bottom of the address space, which is undesirable because it
     // effectively defeats ASLR.
@@ skipping 57 matching lines @@
       base::CommandLine::StringVector bootstrap_prepend;
       bootstrap_prepend.push_back(helper_exe.value());
       bootstrap_prepend.push_back(kNaClHelperReservedAtZero);
       bootstrap_prepend.push_back(kNaClHelperRDebug);
       argv_to_launch.insert(argv_to_launch.begin() + 1,
                             bootstrap_prepend.begin(),
                             bootstrap_prepend.end());
     }
 
     base::LaunchOptions options;
+    options.fds_to_remap.push_back(
+        std::make_pair(fds[1], kNaClZygoteDescriptor));
+    options.fds_to_remap.push_back(
+        std::make_pair(sandboxdesc, nacl_sandbox_descriptor));
 
     base::ScopedFD dummy_fd;
     if (using_setuid_sandbox) {
       // NaCl needs to keep tight control of the cmd_line, so prepend the
       // setuid sandbox wrapper manually.
       base::FilePath sandbox_path = setuid_sandbox_host->GetSandboxBinaryPath();
       argv_to_launch.insert(argv_to_launch.begin(), sandbox_path.value());
-      setuid_sandbox_host->SetupLaunchOptions(&options, &fds_to_map, &dummy_fd);
+      setuid_sandbox_host->SetupLaunchOptions(&options, &dummy_fd);
       setuid_sandbox_host->SetupLaunchEnvironment();
     }
 
-    options.fds_to_remap = &fds_to_map;
-
     // The NaCl processes spawned may need to exceed the ambient soft limit
     // on RLIMIT_AS to allocate the untrusted address space and its guard
     // regions.  The nacl_helper itself cannot just raise its own limit,
     // because the existing limit may prevent the initial exec of
     // nacl_helper_bootstrap from succeeding, with its large address space
     // reservation.
     std::vector<int> max_these_limits;
     max_these_limits.push_back(RLIMIT_AS);
     options.maximize_rlimits = &max_these_limits;
 
@@ skipping 178 matching lines @@
   pass_through_vars.push_back(kNaClVerbosity);
   pass_through_vars.push_back(sandbox::kSandboxEnvironmentApiRequest);
   for (size_t i = 0; i < pass_through_vars.size(); ++i) {
     std::string temp;
     if (env->GetVar(pass_through_vars[i], &temp))
       options->environ[pass_through_vars[i]] = temp;
   }
 }
 
 }  // namespace nacl