[Mac] Log registers with stackdump in debug crashes.

Expand |StackDumpSignalHandler()| to log register contents and part of the stack.

BUG=60426
TEST=Bug's crashes get registers logged.

Review URL: http://codereview.chromium.org/5243002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@67012 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 51 insertions, 7 deletions

diff --git a/base/process_util_posix.cc b/base/process_util_posix.cc
index 07e3125..8a97dcd 100644
--- a/base/process_util_posix.cc
+++ b/base/process_util_posix.cc
@@ -101,9 +101,52 @@ int WaitpidWithTimeout(ProcessHandle handle, int64 wait_milliseconds,
   return status;
 }
 
-void StackDumpSignalHandler(int signal) {
+void StackDumpSignalHandler(int signal, siginfo_t* info, ucontext_t* context) {
   LOG(ERROR) << "Received signal " << signal;
   debug::StackTrace().PrintBacktrace();
+
+  // TODO(shess): Port to Linux.
+#if defined(OS_MACOSX)
+  // TODO(shess): Port to 64-bit.
+#if ARCH_CPU_32_BITS
+  char buf[1024];
+  size_t len;
+
+  // NOTE: Even |snprintf()| is not on the approved list for signal
+  // handlers, but buffered I/O is definitely not on the list due to
+  // potential for |malloc()|.
+  len = static_cast<size_t>(
+      snprintf(buf, sizeof(buf),
+               "ax: %x, bx: %x, cx: %x, dx: %x\n",
+               context->uc_mcontext->__ss.__eax,
+               context->uc_mcontext->__ss.__ebx,
+               context->uc_mcontext->__ss.__ecx,
+               context->uc_mcontext->__ss.__edx));
+  write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
+
+  len = static_cast<size_t>(
+      snprintf(buf, sizeof(buf),
+               "di: %x, si: %x, bp: %x, sp: %x, ss: %x, flags: %x\n",
+               context->uc_mcontext->__ss.__edi,
+               context->uc_mcontext->__ss.__esi,
+               context->uc_mcontext->__ss.__ebp,
+               context->uc_mcontext->__ss.__esp,
+               context->uc_mcontext->__ss.__ss,
+               context->uc_mcontext->__ss.__eflags));
+  write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
+
+  len = static_cast<size_t>(
+      snprintf(buf, sizeof(buf),
+               "ip: %x, cs: %x, ds: %x, es: %x, fs: %x, gs: %x\n",
+               context->uc_mcontext->__ss.__eip,
+               context->uc_mcontext->__ss.__cs,
+               context->uc_mcontext->__ss.__ds,
+               context->uc_mcontext->__ss.__es,
+               context->uc_mcontext->__ss.__fs,
+               context->uc_mcontext->__ss.__gs));
+  write(STDERR_FILENO, buf, std::min(len, sizeof(buf) - 1));
+#endif  // ARCH_CPU_32_BITS
+#endif  // defined(OS_MACOSX)
   _exit(1);
 }
 
@@ -571,12 +614,13 @@ bool EnableInProcessStackDumping() {
   sigemptyset(&action.sa_mask);
   bool success = (sigaction(SIGPIPE, &action, NULL) == 0);
 
-  success &= (signal(SIGILL, &StackDumpSignalHandler) != SIG_ERR);
-  success &= (signal(SIGABRT, &StackDumpSignalHandler) != SIG_ERR);
-  success &= (signal(SIGFPE, &StackDumpSignalHandler) != SIG_ERR);
-  success &= (signal(SIGBUS, &StackDumpSignalHandler) != SIG_ERR);
-  success &= (signal(SIGSEGV, &StackDumpSignalHandler) != SIG_ERR);
-  success &= (signal(SIGSYS, &StackDumpSignalHandler) != SIG_ERR);
+  sig_t handler = reinterpret_cast<sig_t>(&StackDumpSignalHandler);
+  success &= (signal(SIGILL, handler) != SIG_ERR);
+  success &= (signal(SIGABRT, handler) != SIG_ERR);
+  success &= (signal(SIGFPE, handler) != SIG_ERR);
+  success &= (signal(SIGBUS, handler) != SIG_ERR);
+  success &= (signal(SIGSEGV, handler) != SIG_ERR);
+  success &= (signal(SIGSYS, handler) != SIG_ERR);
 
   return success;
 }