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