summaryrefslogtreecommitdiffstats
path: root/chrome/app/chrome_dll_main.cc
blob: ee75d766ea716c9f97efaa9d258a2e7abf8fefc2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
// Copyright (c) 2009 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.

// TODO(port): the ifdefs in here are a first step towards trying to determine
// the correct abstraction for all the OS functionality required at this
// stage of process initialization. It should not be taken as a final
// abstraction.

#include "build/build_config.h"

#if defined(OS_WIN)
#include <algorithm>
#include <atlbase.h>
#include <atlapp.h>
#include <malloc.h>
#include <new.h>
#elif defined(OS_POSIX)
#include <locale.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#endif

#if defined(OS_LINUX)
#include <gdk/gdk.h>
#include <glib.h>
#include <gtk/gtk.h>
#include <stdlib.h>
#include <string.h>
#endif

#include "app/app_paths.h"
#include "app/app_switches.h"
#include "app/resource_bundle.h"
#include "base/at_exit.h"
#include "base/command_line.h"
#include "base/debug_util.h"
#include "base/i18n/icu_util.h"
#include "base/message_loop.h"
#include "base/path_service.h"
#include "base/process_util.h"
#include "base/scoped_nsautorelease_pool.h"
#include "base/stats_counters.h"
#include "base/stats_table.h"
#include "base/string_util.h"
#include "chrome/browser/diagnostics/diagnostics_main.h"
#include "chrome/browser/renderer_host/render_process_host.h"
#include "chrome/common/chrome_constants.h"
#include "chrome/common/chrome_counters.h"
#include "chrome/common/chrome_descriptors.h"
#include "chrome/common/chrome_paths.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/common/logging_chrome.h"
#include "chrome/common/main_function_params.h"
#include "chrome/common/sandbox_init_wrapper.h"
#include "ipc/ipc_switches.h"

#if defined(OS_LINUX)
#include "base/nss_init.h"
#include "chrome/browser/renderer_host/render_sandbox_host_linux.h"
#include "chrome/browser/zygote_host_linux.h"
#endif

#if defined(OS_MACOSX)
#include "base/mac_util.h"
#include "chrome/common/chrome_paths_internal.h"
#include "chrome/app/breakpad_mac.h"
#include "third_party/WebKit/WebKit/mac/WebCoreSupport/WebSystemInterface.h"
#endif

#if defined(OS_POSIX)
#include "base/global_descriptors_posix.h"
#endif

#if defined(OS_WIN)
#include "base/win_util.h"
#include "sandbox/src/sandbox.h"
#include "tools/memory_watcher/memory_watcher.h"
#endif

#if defined(USE_TCMALLOC)
#include "third_party/tcmalloc/chromium/src/google/malloc_extension.h"
#endif

extern int BrowserMain(const MainFunctionParams&);
extern int RendererMain(const MainFunctionParams&);
extern int PluginMain(const MainFunctionParams&);
extern int WorkerMain(const MainFunctionParams&);
extern int NaClMain(const MainFunctionParams&);
extern int UtilityMain(const MainFunctionParams&);
extern int ProfileImportMain(const MainFunctionParams&);
extern int ZygoteMain(const MainFunctionParams&);
#ifdef NACL_WIN64
extern int NaClBrokerMain(const MainFunctionParams&);
#endif

#if defined(OS_WIN)
// TODO(erikkay): isn't this already defined somewhere?
#define DLLEXPORT __declspec(dllexport)

// We use extern C for the prototype DLLEXPORT to avoid C++ name mangling.
extern "C" {
DLLEXPORT int __cdecl ChromeMain(HINSTANCE instance,
                                 sandbox::SandboxInterfaceInfo* sandbox_info,
                                 TCHAR* command_line);
}
#elif defined(OS_POSIX)
extern "C" {
__attribute__((visibility("default")))
int ChromeMain(int argc, char** argv);
}
#endif

namespace {

#if defined(OS_WIN)
const wchar_t kProfilingDll[] = L"memory_watcher.dll";

// Load the memory profiling DLL.  All it needs to be activated
// is to be loaded.  Return true on success, false otherwise.
bool LoadMemoryProfiler() {
  HMODULE prof_module = LoadLibrary(kProfilingDll);
  return prof_module != NULL;
}

CAppModule _Module;

#pragma optimize("", off)
// Handlers for invalid parameter and pure call. They generate a breakpoint to
// tell breakpad that it needs to dump the process.
void InvalidParameter(const wchar_t* expression, const wchar_t* function,
                      const wchar_t* file, unsigned int line,
                      uintptr_t reserved) {
  __debugbreak();
}

void PureCall() {
  __debugbreak();
}

#pragma warning( push )
// Disables warning 4748 which is: "/GS can not protect parameters and local
// variables from local buffer overrun because optimizations are disabled in
// function."  GetStats() will not overflow the passed-in buffer and this
// function never returns.
#pragma warning( disable : 4748 )
void OnNoMemory() {
#if defined(USE_TCMALLOC)
  // Try to get some information on the stack to make the crash easier to
  // diagnose from a minidump, being very careful not to do anything that might
  // try to heap allocate.
  char buf[32*1024];
  MallocExtension::instance()->GetStats(buf, sizeof(buf));
#endif
  // Kill the process. This is important for security, since WebKit doesn't
  // NULL-check many memory allocations. If a malloc fails, returns NULL, and
  // the buffer is then used, it provides a handy mapping of memory starting at
  // address 0 for an attacker to utilize.
  __debugbreak();
}
#pragma warning( pop )

// Handlers to silently dump the current process when there is an assert in
// chrome.
void ChromeAssert(const std::string& str) {
  // Get the breakpad pointer from chrome.exe
  typedef void (__cdecl *DumpProcessFunction)();
  DumpProcessFunction DumpProcess = reinterpret_cast<DumpProcessFunction>(
      ::GetProcAddress(::GetModuleHandle(chrome::kBrowserProcessExecutableName),
                       "DumpProcess"));
  if (DumpProcess)
    DumpProcess();
}

#pragma optimize("", on)

// Early versions of Chrome incorrectly registered a chromehtml: URL handler,
// which gives us nothing but trouble. Avoid launching chrome this way since
// some apps fail to properly escape arguments.
bool HasDeprecatedArguments(const std::wstring& command_line) {
  const wchar_t kChromeHtml[] = L"chromehtml:";
  std::wstring command_line_lower = command_line;
  // We are only searching for ASCII characters so this is OK.
  StringToLowerASCII(&command_line_lower);
  std::wstring::size_type pos = command_line_lower.find(kChromeHtml);
  return (pos != std::wstring::npos);
}

#endif  // OS_WIN

#if defined(OS_LINUX)
static void GLibLogHandler(const gchar* log_domain,
                           GLogLevelFlags log_level,
                           const gchar* message,
                           gpointer userdata) {
  if (!log_domain)
    log_domain = "<unknown>";
  if (!message)
    message = "<no message>";

  if (strstr(message, "Loading IM context type") ||
      strstr(message, "wrong ELF class: ELFCLASS64")) {
    // http://crbug.com/9643
    // Until we have a real 64-bit build or all of these 32-bit package issues
    // are sorted out, don't fatal on ELF 32/64-bit mismatch warnings and don't
    // spam the user with more than one of them.
    static bool alerted = false;
    if (!alerted) {
      LOG(ERROR) << "Bug 9643: " << log_domain << ": " << message;
      alerted = true;
    }
  } else if (strstr(message, "gtk_widget_size_allocate(): attempt to "
                             "allocate widget with width") &&
             !GTK_CHECK_VERSION(2, 16, 1)) {
    // This warning only occurs in obsolete versions of GTK and is harmless.
    // http://crbug.com/11133
  } else if (strstr(message, "Theme file for default has no") ||
             strstr(message, "Theme directory") ||
             strstr(message, "theme pixmap")) {
    LOG(ERROR) << "GTK theme error: " << message;
  } else if (strstr(message, "gtk_drag_dest_leave: assertion")) {
    LOG(ERROR) << "Drag destination deleted: http://crbug.com/18557";
  } else {
#ifdef NDEBUG
    LOG(ERROR) << log_domain << ": " << message;
#else
    LOG(FATAL) << log_domain << ": " << message;
#endif
  }
}

static void SetUpGLibLogHandler() {
  // Register GLib-handled assertions to go through our logging system.
  const char* kLogDomains[] = { NULL, "Gtk", "Gdk", "GLib", "GLib-GObject" };
  for (size_t i = 0; i < arraysize(kLogDomains); i++) {
    g_log_set_handler(kLogDomains[i],
                      static_cast<GLogLevelFlags>(G_LOG_FLAG_RECURSION |
                                                  G_LOG_FLAG_FATAL |
                                                  G_LOG_LEVEL_ERROR |
                                                  G_LOG_LEVEL_CRITICAL |
                                                  G_LOG_LEVEL_WARNING),
                      GLibLogHandler,
                      NULL);
  }
}

static void AdjustLinuxOOMScore(const std::string& process_type) {
  const int kMiscScore = 7;
  const int kPluginScore = 10;
  int score = -1;

  if (process_type == switches::kPluginProcess) {
    score = kPluginScore;
  } else if (process_type == switches::kUtilityProcess ||
             process_type == switches::kWorkerProcess) {
    score = kMiscScore;
  } else if (process_type == switches::kProfileImportProcess) {
    NOTIMPLEMENTED();
#ifndef DISABLE_NACL
  } else if (process_type == switches::kNaClProcess) {
    score = kPluginScore;
#endif
  } else if (process_type == switches::kZygoteProcess ||
             process_type.empty()) {
    // Pass - browser / zygote process stays at 0.
  } else if (process_type == switches::kExtensionProcess ||
             process_type == switches::kRendererProcess) {
    // Set in chrome/browser/zygote_host_linux.cc.
    NOTREACHED() << "process type " << process_type
                 << "should go through the zygote.";
  } else {
    NOTREACHED() << "Unknown process type";
  }
  if (score > -1)
    base::AdjustOOMScore(base::GetCurrentProcId(), score);
}
#endif  // defined(OS_LINUX)

// Register the invalid param handler and pure call handler to be able to
// notify breakpad when it happens.
void RegisterInvalidParamHandler() {
#if defined(OS_WIN)
  _set_invalid_parameter_handler(InvalidParameter);
  _set_purecall_handler(PureCall);
  // Gather allocation failure.
  std::set_new_handler(&OnNoMemory);
  // Also enable the new handler for malloc() based failures.
  _set_new_mode(1);
#endif
}

void SetupCRT(const CommandLine& parsed_command_line) {
#if defined(OS_WIN)
#ifdef _CRTDBG_MAP_ALLOC
  _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
  _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
#else
  if (!parsed_command_line.HasSwitch(switches::kDisableBreakpad)) {
    _CrtSetReportMode(_CRT_ASSERT, 0);
  }
#endif

  // Enable the low fragmentation heap for the CRT heap. The heap is not changed
  // if the process is run under the debugger is enabled or if certain gflags
  // are set.
  bool use_lfh = false;
  if (parsed_command_line.HasSwitch(switches::kUseLowFragHeapCrt))
    use_lfh = parsed_command_line.GetSwitchValue(switches::kUseLowFragHeapCrt)
        != L"false";
  if (use_lfh) {
    void* crt_heap = reinterpret_cast<void*>(_get_heap_handle());
    ULONG enable_lfh = 2;
    HeapSetInformation(crt_heap, HeapCompatibilityInformation,
                       &enable_lfh, sizeof(enable_lfh));
  }
#endif
}

// Enable the heap profiler if the appropriate command-line switch is
// present, bailing out of the app we can't.
void EnableHeapProfiler(const CommandLine& parsed_command_line) {
#if defined(OS_WIN)
  if (parsed_command_line.HasSwitch(switches::kMemoryProfiling))
    if (!LoadMemoryProfiler())
      exit(-1);
#endif
}

void CommonSubprocessInit() {
#if defined(OS_WIN)
  // HACK: Let Windows know that we have started.  This is needed to suppress
  // the IDC_APPSTARTING cursor from being displayed for a prolonged period
  // while a subprocess is starting.
  PostThreadMessage(GetCurrentThreadId(), WM_NULL, 0, 0);
  MSG msg;
  PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
#endif
}

// Returns true if this subprocess type needs the ResourceBundle initialized
// and resources loaded.
bool SubprocessNeedsResourceBundle(const std::string& process_type) {
  return
#if defined(OS_WIN)
      // Windows needs resources for the default/null plugin.
      process_type == switches::kPluginProcess ||
#endif
#if defined(OS_LINUX)
      // The zygote process opens the resources for the renderers.
      process_type == switches::kZygoteProcess ||
#endif
      process_type == switches::kRendererProcess ||
      process_type == switches::kExtensionProcess;
}

}  // namespace

#if defined(OS_WIN)
DLLEXPORT int __cdecl ChromeMain(HINSTANCE instance,
                                 sandbox::SandboxInterfaceInfo* sandbox_info,
                                 TCHAR* command_line) {
#elif defined(OS_POSIX)
int ChromeMain(int argc, char** argv) {
#endif

#if defined(OS_MACOSX)
  // TODO(mark): Some of these things ought to be handled in chrome_exe_main.mm.
  // Under the current architecture, nothing in chrome_exe_main can rely
  // directly on chrome_dll code on the Mac, though, so until some of this code
  // is refactored to avoid such a dependency, it lives here.  See also the
  // TODO(mark) below at InitCrashReporter() and DestructCrashReporter().
  base::EnableTerminationOnHeapCorruption();
  base::EnableTerminationOnOutOfMemory();
#endif  // OS_MACOSX

  RegisterInvalidParamHandler();

  // The exit manager is in charge of calling the dtors of singleton objects.
  base::AtExitManager exit_manager;

  // 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.
  base::ScopedNSAutoreleasePool autorelease_pool;

#if defined(OS_POSIX)
  base::GlobalDescriptors* g_fds = Singleton<base::GlobalDescriptors>::get();
  g_fds->Set(kPrimaryIPCChannel,
             kPrimaryIPCChannel + base::GlobalDescriptors::kBaseDescriptor);
#if defined(OS_LINUX)
  g_fds->Set(kCrashDumpSignal,
             kCrashDumpSignal + base::GlobalDescriptors::kBaseDescriptor);
#endif
#endif

#if defined(OS_POSIX)
  // Set C library locale to make sure CommandLine can parse argument values
  // in correct encoding.
  setlocale(LC_ALL, "");

  // 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(0 == sigemptyset(&empty_signal_set));
  CHECK(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(0 == sigaction(signals_to_reset[i], &sigact, NULL));
  }
#endif

  // Initialize the command line.
#if defined(OS_WIN)
  CommandLine::Init(0, NULL);
#else
  CommandLine::Init(argc, argv);
#endif

  const CommandLine& parsed_command_line = *CommandLine::ForCurrentProcess();
  std::string process_type =
      parsed_command_line.GetSwitchValueASCII(switches::kProcessType);

  // If we are in diagnostics mode this is the end of the line. After the
  // diagnostics are run the process will invariably exit.
  if (parsed_command_line.HasSwitch(switches::kDiagnostics)) {
    return DiagnosticsMain(parsed_command_line);
  }

#if defined(OS_MACOSX)
  mac_util::SetOverrideAppBundlePath(chrome::GetFrameworkBundlePath());
#endif  // OS_MACOSX

#if defined(OS_WIN)
  // Must do this before any other usage of command line!
  if (HasDeprecatedArguments(parsed_command_line.command_line_string()))
    return 1;
#endif

#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
  // Show the man page on --help or -h.
  if (parsed_command_line.HasSwitch("help") ||
      parsed_command_line.HasSwitch("h")) {
    FilePath binary(parsed_command_line.argv()[0]);
    execlp("man", "man", binary.BaseName().value().c_str(), NULL);
    PLOG(FATAL) << "execlp failed";
  }
#endif

#if defined(OS_POSIX)
  // Always ignore SIGPIPE.  We check the return value of write().
  CHECK(signal(SIGPIPE, SIG_IGN) != SIG_ERR);
#endif  // OS_POSIX

  base::ProcessId browser_pid;
  if (process_type.empty()) {
    browser_pid = base::GetCurrentProcId();
  } else {
#if defined(OS_WIN)
    std::wstring channel_name =
      parsed_command_line.GetSwitchValue(switches::kProcessChannelID);

    browser_pid =
        static_cast<base::ProcessId>(StringToInt(WideToASCII(channel_name)));
    DCHECK_NE(browser_pid, 0);
#else
    browser_pid = base::GetCurrentProcId();
#endif

#if defined(OS_POSIX)
    // When you hit Ctrl-C in a terminal running the browser
    // process, a SIGINT is delivered to the entire process group.
    // When debugging the browser process via gdb, gdb catches the
    // SIGINT for the browser process (and dumps you back to the gdb
    // console) but doesn't for the child processes, killing them.
    // The fix is to have child processes ignore SIGINT; they'll die
    // on their own when the browser process goes away.
    // Note that we *can't* rely on DebugUtil::BeingDebugged to catch this
    // case because we are the child process, which is not being debugged.
    if (!DebugUtil::BeingDebugged())
      signal(SIGINT, SIG_IGN);
#endif
  }
  SetupCRT(parsed_command_line);

  // Initialize the Chrome path provider.
  app::RegisterPathProvider();
  chrome::RegisterPathProvider();

#if defined(OS_MACOSX)
  // TODO(mark): Right now, InitCrashReporter() needs to be called after
  // CommandLine::Init() and chrome::RegisterPathProvider().  Ideally, Breakpad
  // initialization could occur sooner, preferably even before the framework
  // dylib is even loaded, to catch potential early crashes.
  InitCrashReporter();

#if defined(NDEBUG)
  bool is_debug_build = false;
#else
  bool is_debug_build = true;
#endif

  // Details on when we enable Apple's Crash reporter.
  //
  // Motivation:
  //    In debug mode it takes Apple's crash reporter eons to generate a crash
  // dump.
  //
  // What we do:
  // * We only pass crashes for foreground processes to Apple's Crash reporter.
  //    At the time of this writing, that means just the Browser process.
  // * If Breakpad is enabled, it will pass browser crashes to Crash Reporter
  //    itself.
  // * If Breakpad is disabled, we only turn on Crash Reporter for the
  //    Browser process in release mode.
  if (!parsed_command_line.HasSwitch(switches::kDisableBreakpad)) {
    bool disable_apple_crash_reporter = is_debug_build
                                        || mac_util::IsBackgroundOnlyProcess();
    if (!IsCrashReporterEnabled() && disable_apple_crash_reporter) {
      DebugUtil::DisableOSCrashDumps();
    }
  }

  if (IsCrashReporterEnabled())
    InitCrashProcessInfo();
#endif  // OS_MACOSX

  // Initialize the Stats Counters table.  With this initialized,
  // the StatsViewer can be utilized to read counters outside of
  // Chrome.  These lines can be commented out to effectively turn
  // counters 'off'.  The table is created and exists for the life
  // of the process.  It is not cleaned up.
  // TODO(port): we probably need to shut this down correctly to avoid
  // leaking shared memory regions on posix platforms.
  if (parsed_command_line.HasSwitch(switches::kEnableStatsTable) ||
      parsed_command_line.HasSwitch(switches::kEnableBenchmarking)) {
    std::string statsfile =
        StringPrintf("%s-%u", chrome::kStatsFilename,
                     static_cast<unsigned int>(browser_pid));
    StatsTable *stats_table = new StatsTable(statsfile,
        chrome::kStatsMaxThreads, chrome::kStatsMaxCounters);
    StatsTable::set_current(stats_table);
  }

  StatsScope<StatsCounterTimer>
      startup_timer(chrome::Counters::chrome_main());

  // Enable the heap profiler as early as possible!
  EnableHeapProfiler(parsed_command_line);

  // Enable Message Loop related state asap.
  if (parsed_command_line.HasSwitch(switches::kMessageLoopHistogrammer))
    MessageLoop::EnableHistogrammer(true);

  // Checks if the sandbox is enabled in this process and initializes it if this
  // is the case. The crash handler depends on this so it has to be done before
  // its initialization.
  SandboxInitWrapper sandbox_wrapper;
#if defined(OS_WIN)
  sandbox_wrapper.SetServices(sandbox_info);
#endif

  // OS X enables sandboxing later in the startup process.
#if !defined (OS_MACOSX)
  sandbox_wrapper.InitializeSandbox(parsed_command_line, process_type);
#endif  // !OS_MACOSX

#if defined(OS_WIN)
  _Module.Init(NULL, instance);
#endif

  // Notice a user data directory override if any
  const FilePath user_data_dir =
      parsed_command_line.GetSwitchValuePath(switches::kUserDataDir);
  if (!user_data_dir.empty())
    CHECK(PathService::Override(chrome::DIR_USER_DATA, user_data_dir));

  bool single_process =
#if defined (GOOGLE_CHROME_BUILD)
    // This is an unsupported and not fully tested mode, so don't enable it for
    // official Chrome builds.
    false;
#else
    parsed_command_line.HasSwitch(switches::kSingleProcess);
#endif
  if (single_process)
    RenderProcessHost::set_run_renderer_in_process(true);
#if defined(OS_MACOSX)
  // TODO(port-mac): This is from renderer_main_platform_delegate.cc.
  // shess tried to refactor things appropriately, but it sprawled out
  // of control because different platforms needed different styles of
  // initialization.  Try again once we understand the process
  // architecture needed and where it should live.
  if (single_process)
    InitWebCoreSystemInterface();
#endif

  bool icu_result = icu_util::Initialize();
  CHECK(icu_result);

  logging::OldFileDeletionState file_state =
      logging::APPEND_TO_OLD_LOG_FILE;
  if (process_type.empty()) {
    file_state = logging::DELETE_OLD_LOG_FILE;
  }
  logging::InitChromeLogging(parsed_command_line, file_state);

#ifdef NDEBUG
  if (parsed_command_line.HasSwitch(switches::kSilentDumpOnDCHECK) &&
      parsed_command_line.HasSwitch(switches::kEnableDCHECK)) {
#if defined(OS_WIN)
    logging::SetLogReportHandler(ChromeAssert);
#endif
  }
#endif  // NDEBUG

  if (SubprocessNeedsResourceBundle(process_type)) {
    // Initialize ResourceBundle which handles files loaded from external
    // sources.  The language should have been passed in to us from the
    // browser process as a command line flag.
    DCHECK(parsed_command_line.HasSwitch(switches::kLang) ||
           process_type == switches::kZygoteProcess);
    ResourceBundle::InitSharedInstance(std::wstring());
  }

  if (!process_type.empty())
    CommonSubprocessInit();

#if defined(OS_MACOSX)
  // On OS X the renderer sandbox needs to be initialized later in the startup
  // sequence in RendererMainPlatformDelegate::PlatformInitialize().
  if (process_type != switches::kRendererProcess &&
      process_type != switches::kExtensionProcess) {
    bool sandbox_initialized_ok =
        sandbox_wrapper.InitializeSandbox(parsed_command_line, process_type);
    // Die if the sandbox can't be enabled.
    CHECK(sandbox_initialized_ok) << "Error initializing sandbox for "
                                  << process_type;
  }
#endif  // OS_MACOSX

  startup_timer.Stop();  // End of Startup Time Measurement.

  MainFunctionParams main_params(parsed_command_line, sandbox_wrapper,
                                 &autorelease_pool);

  // Note: If you are adding a new process type below, be sure to adjust the
  // AdjustLinuxOOMScore function too.
#if defined(OS_LINUX)
  AdjustLinuxOOMScore(process_type);
#endif

  // TODO(port): turn on these main() functions as they've been de-winified.
  int rv = -1;
  if (process_type == switches::kRendererProcess) {
    rv = RendererMain(main_params);
  } else if (process_type == switches::kExtensionProcess) {
    // An extension process is just a renderer process. We use a different
    // command line argument to differentiate crash reports.
    rv = RendererMain(main_params);
  } else if (process_type == switches::kPluginProcess) {
    rv = PluginMain(main_params);
  } else if (process_type == switches::kUtilityProcess) {
    rv = UtilityMain(main_params);
  } else if (process_type == switches::kProfileImportProcess) {
#if defined(OS_MACOSX)
    rv = ProfileImportMain(main_params);
#else
    // TODO(port): Use OOP profile import - http://crbug.com/22142 .
    NOTIMPLEMENTED();
    rv = -1;
#endif
  } else if (process_type == switches::kWorkerProcess) {
    rv = WorkerMain(main_params);
#ifndef DISABLE_NACL
  } else if (process_type == switches::kNaClProcess) {
    rv = NaClMain(main_params);
#endif
  } else if (process_type == switches::kZygoteProcess) {
#if defined(OS_LINUX)
    if (ZygoteMain(main_params)) {
      // Zygote::HandleForkRequest may have reallocated the command
      // line so update it here with the new version.
      const CommandLine& parsed_command_line =
        *CommandLine::ForCurrentProcess();
      MainFunctionParams main_params(parsed_command_line, sandbox_wrapper,
                                     &autorelease_pool);
      rv = RendererMain(main_params);
    } else {
      rv = 0;
    }
#else
    NOTIMPLEMENTED();
#endif
  } else if (process_type.empty()) {
#if defined(OS_LINUX)
    const char* sandbox_binary = NULL;
    struct stat st;

    // In Chromium branded builds, developers can set an environment variable to
    // use the development sandbox. See
    // http://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment
    if (stat("/proc/self/exe", &st) == 0 && st.st_uid == getuid())
      sandbox_binary = getenv("CHROME_DEVEL_SANDBOX");

#if defined(LINUX_SANDBOX_PATH)
    if (!sandbox_binary)
      sandbox_binary = LINUX_SANDBOX_PATH;
#endif

    std::string sandbox_cmd;
    if (sandbox_binary)
      sandbox_cmd = sandbox_binary;

    // Tickle the sandbox host and zygote host so they fork now.
    RenderSandboxHostLinux* shost = Singleton<RenderSandboxHostLinux>::get();
    shost->Init(sandbox_cmd);
    ZygoteHost* zhost = Singleton<ZygoteHost>::get();
    zhost->Init(sandbox_cmd);

    // We want to be sure to init NSPR on the main thread.
    base::EnsureNSPRInit();

    g_thread_init(NULL);
    // Glib type system initialization. Needed at least for gconf,
    // used in net/proxy/proxy_config_service_linux.cc. Most likely
    // this is superfluous as gtk_init() ought to do this. It's
    // definitely harmless, so retained as a reminder of this
    // requirement for gconf.
    g_type_init();
    // gtk_init() can change |argc| and |argv|.
    gtk_init(&argc, &argv);
    SetUpGLibLogHandler();
#endif  // defined(OS_LINUX)

    rv = BrowserMain(main_params);
  } else {
    NOTREACHED() << "Unknown process type";
  }

  if (SubprocessNeedsResourceBundle(process_type))
    ResourceBundle::CleanupSharedInstance();

#if defined(OS_WIN)
#ifdef _CRTDBG_MAP_ALLOC
  _CrtDumpMemoryLeaks();
#endif  // _CRTDBG_MAP_ALLOC

  _Module.Term();
#endif

  logging::CleanupChromeLogging();

#if defined(OS_MACOSX) && defined(GOOGLE_CHROME_BUILD)
  // TODO(mark): See the TODO(mark) above at InitCrashReporter.
  DestructCrashReporter();
#endif  // OS_MACOSX && GOOGLE_CHROME_BUILD

  return rv;
}