Move some basic early process init into Service Manager

services/service_manager/embedder/main.cc

+// Copyright 2017 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 "services/service_manager/embedder/main.h"
+#include "base/allocator/features.h"
+#include "base/command_line.h"
+#include "base/logging.h"
+#include "base/memory/ptr_util.h"
+#include "base/process/memory.h"
+#include "mojo/edk/embedder/embedder.h"
+#include "services/service_manager/embedder/main_delegate.h"
+#include "services/service_manager/embedder/set_process_title.h"
+#include "services/service_manager/embedder/shared_file_util.h"
+#include "services/service_manager/embedder/switches.h"
+
+#if defined(OS_WIN)
+#include "base/win/process_startup_helper.h"
+#include "ui/base/win/atl_module.h"
+#endif
+
+#if defined(OS_POSIX) && !defined(OS_ANDROID)
+#include <locale.h>
+#include <signal.h>
+
+#include "base/file_descriptor_store.h"
+#include "base/posix/global_descriptors.h"
+#endif
+
+#if defined(OS_MACOSX)
+#include "base/mac/scoped_nsautorelease_pool.h"
+#include "services/service_manager/embedder/mac_init.h"
+#endif
+
+namespace service_manager {
+
+namespace {
+
+// Maximum message size allowed to be read from a Mojo message pipe in any
+// service manager embedder process.
+constexpr size_t kMaximumMojoMessageSize = 128 * 1024 * 1024;
+
+#if defined(OS_POSIX) && !defined(OS_ANDROID)
+
+// Setup signal-handling state: resanitize most signals, ignore SIGPIPE.
+void SetupSignalHandlers() {
+  // Sanitise our signal handling state. Signals that were ignored by our
+  // parent will also be ignored by us. We also inherit our parent's sigmask.
+  sigset_t empty_signal_set;
+  CHECK_EQ(0, sigemptyset(&empty_signal_set));
+  CHECK_EQ(0, sigprocmask(SIG_SETMASK, &empty_signal_set, NULL));
+
+  struct sigaction sigact;
+  memset(&sigact, 0, sizeof(sigact));
+  sigact.sa_handler = SIG_DFL;
+  static const int signals_to_reset[] = {
+      SIGHUP,  SIGINT,  SIGQUIT, SIGILL, SIGABRT, SIGFPE, SIGSEGV,
+      SIGALRM, SIGTERM, SIGCHLD, SIGBUS, SIGTRAP};  // SIGPIPE is set below.
+  for (unsigned i = 0; i < arraysize(signals_to_reset); i++) {
+    CHECK_EQ(0, sigaction(signals_to_reset[i], &sigact, NULL));
+  }
+
+  // Always ignore SIGPIPE.  We check the return value of write().
+  CHECK_NE(SIG_ERR, signal(SIGPIPE, SIG_IGN));
+}
+
+void PopulateFDsFromCommandLine() {
+  const std::string& shared_file_param =
+      base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+          switches::kSharedFiles);
+  if (shared_file_param.empty())
+    return;
+
+  base::Optional<std::map<int, std::string>> shared_file_descriptors =
+      service_manager::ParseSharedFileSwitchValue(shared_file_param);
+  if (!shared_file_descriptors)
+    return;
+
+  for (const auto& descriptor : *shared_file_descriptors) {
+    base::MemoryMappedFile::Region region;
+    const std::string& key = descriptor.second;
+    base::ScopedFD fd = base::GlobalDescriptors::GetInstance()->TakeFD(
+        descriptor.first, &region);
+    base::FileDescriptorStore::GetInstance().Set(key, std::move(fd), region);
+  }
+}
+
+#endif  // defined(OS_POSIX) && !defined(OS_ANDROID)
+
+}  // namespace
+
+MainParams::MainParams(MainDelegate* delegate) : delegate(delegate) {}
+
+MainParams::~MainParams() {}
+
+int Main(const MainParams& params) {
+  MainDelegate* delegate = params.delegate;
+  DCHECK(delegate);
+
+#if defined(OS_MACOSX) && BUILDFLAG(USE_EXPERIMENTAL_ALLOCATOR_SHIM)
+  base::allocator::InitializeAllocatorShim();
+#endif
+  base::EnableTerminationOnOutOfMemory();
+
+#if defined(OS_WIN)
+  base::win::RegisterInvalidParamHandler();
+  ui::win::CreateATLModuleIfNeeded();
+#endif  // defined(OS_WIN)
+
+// On Android setlocale() is not supported, and we don't override the signal
+// handlers so we can get a stack trace when crashing.
+#if defined(OS_POSIX) && !defined(OS_ANDROID)
+  // Set C library locale to make sure CommandLine can parse argument values in
+  // the correct encoding.
+  setlocale(LC_ALL, "");
+
+  SetupSignalHandlers();
+#endif
+
+#if !defined(OS_ANDROID)
+  // On Android, the command line is initialized when library is loaded.
+  int argc = 0;
+  const char** argv = nullptr;
+
+#if defined(OS_POSIX)
+  // argc/argv are ignored on Windows; see command_line.h for details.
+  argc = params.argc;
+  argv = params.argv;
+#endif
+
+  base::CommandLine::Init(argc, argv);
+
+#if defined(OS_POSIX)
+  PopulateFDsFromCommandLine();
+#endif
+
+  base::EnableTerminationOnHeapCorruption();
+
+  SetProcessTitleFromCommandLine(argv);
+#endif  // !defined(OS_ANDROID)
+
+  MainDelegate::InitializeParams init_params;
+
+#if defined(OS_MACOSX)
+  // We need this pool for all the objects created before we get to the event
+  // loop, but we don't want to leave them hanging around until the app quits.
+  // Each "main" needs to flush this pool right before it goes into its main
+  // event loop to get rid of the cruft.
+  std::unique_ptr<base::mac::ScopedNSAutoreleasePool> autorelease_pool =
+      base::MakeUnique<base::mac::ScopedNSAutoreleasePool>();
+  init_params.autorelease_pool = autorelease_pool.get();
+  InitializeMac();
+#endif
+
+  mojo::edk::SetMaxMessageSize(kMaximumMojoMessageSize);
+  mojo::edk::Init();
+
+  int exit_code = 0;
+  if (!delegate->Initialize(init_params, &exit_code))
+    return exit_code;
+
+  exit_code = delegate->Run();
+  delegate->ShutDown();
+
+  return exit_code;
+}
+
+}  // namespace service_manager