Upgrade a DLOG(INFO) and remove an fprintf in objc_zombie.mm

These cause unrelated changes to the file to fail presubmit checks.

The INFO becomes a WARNING. It immediately precedes a DLOG(FATAL), so
isn't really spamming.

The fprintf becomes ::write(..). It precedes a
base::debug::StackTrace(..).Print(), which is async-signal safe, so use
use an async-signal safe function beforehand. This is probably overly
paranoid but I'm surrounded by zombies and they scare me.

BUG=None

Review URL: https://codereview.chromium.org/443563002

Cr-Commit-Position: refs/heads/master@{#288888}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@288888 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 5 insertions, 2 deletions

diff --git a/chrome/common/mac/objc_zombie.mm b/chrome/common/mac/objc_zombie.mm
index ab62cae..d0cb063 100644
--- a/chrome/common/mac/objc_zombie.mm
+++ b/chrome/common/mac/objc_zombie.mm
@@ -15,6 +15,7 @@
 #include "base/debug/stack_trace.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
+#include "base/posix/eintr_wrapper.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/lock.h"
 #include "chrome/common/crash_keys.h"
@@ -174,7 +175,9 @@ BOOL GetZombieRecord(id object, ZombieRecord* record) {
 // Dump the symbols.  This is pulled out into a function to make it
 // easy to use DCHECK to dump only in debug builds.
 BOOL DumpDeallocTrace(const void* const* array, int size) {
-  fprintf(stderr, "Backtrace from -dealloc:\n");
+  // Async-signal safe version of fputs, consistent with StackTrace::Print().
+  const char* message = "Backtrace from -dealloc:\n";
+  ignore_result(HANDLE_EINTR(write(STDERR_FILENO, message, strlen(message))));
   base::debug::StackTrace(array, size).Print();
 
   return YES;
@@ -220,7 +223,7 @@ void ZombieObjectCrash(id object, SEL aSelector, SEL viaSelector) {
   if (found && record.traceDepth) {
     DCHECK(DumpDeallocTrace(record.trace, record.traceDepth));
   } else {
-    DLOG(INFO) << "Unable to generate backtrace from -dealloc.";
+    DLOG(WARNING) << "Unable to generate backtrace from -dealloc.";
   }
   DLOG(FATAL) << aString;