base/mac/os_crash_dumps.cc

   1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/mac/os_crash_dumps.h"
   6
   7 #include <signal.h>
   8 #include <unistd.h>
   9
  10 #include "base/basictypes.h"
  11 #include "base/logging.h"
  12
  13 namespace base {
  14 namespace mac {
  15
  16 namespace {
  17
  18 void ExitSignalHandler(int sig) {
  19   // A call to exit() can call atexit() handlers.  If we SIGSEGV due
  20   // to a corrupt heap, and if we have an atexit handler that
  21   // allocates or frees memory, we are in trouble if we do not _exit.
  22   _exit(128 + sig);
  23 }
  24
  25 }  // namespace
  26
  27 void DisableOSCrashDumps() {
  28   // These are the POSIX signals corresponding to the Mach exceptions that
  29   // Apple Crash Reporter handles.  See ux_exception() in xnu's
  30   // bsd/uxkern/ux_exception.c and machine_exception() in xnu's
  31   // bsd/dev/*/unix_signal.c.
  32   const int signals_to_intercept[] = {
  33     // Hardware faults
  34     SIGILL,   // EXC_BAD_INSTRUCTION
  35     SIGTRAP,  // EXC_BREAKPOINT
  36     SIGFPE,   // EXC_ARITHMETIC
  37     SIGBUS,   // EXC_BAD_ACCESS
  38     SIGSEGV,  // EXC_BAD_ACCESS
  39     // Not a hardware fault
  40     SIGABRT
  41   };
  42
  43   // For all these signals, just wire things up so we exit immediately.
  44   for (size_t i = 0; i < arraysize(signals_to_intercept); ++i) {
  45     struct sigaction act = {};
  46     act.sa_handler = ExitSignalHandler;
  47
  48     // It is better to allow the signal handler to run on the stack
  49     // registered with sigaltstack(), if one is present.
  50     act.sa_flags = SA_ONSTACK;
  51
  52     if (sigemptyset(&act.sa_mask) != 0)
  53       DPLOG(FATAL) << "sigemptyset() failed";
  54     if (sigaction(signals_to_intercept[i], &act, NULL) != 0)
  55       DPLOG(FATAL) << "sigaction() failed";
  56   }
  57 }
  58
  59 }  // namespace mac
  60 }  // namespace base