[libcxxabi] Improve logging of aborts for Android.

[danalbert]

Summary

In Android, stderr only goes to the console, and as such will only ever be seen by adb shell users. Since very few developers will ever actually see that, also send the abort message to logcat and the tombstone.

[jroelofs]

LGTM

src/abort_message.cpp

15

Out of curiosity, does the android compiler define this, or does it come from a particular header?

[danalbert]

Submitted as r215983.

src/abort_message.cpp

 //===------------------------- abort_message.cpp --------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is dual licensed under the MIT and the University of Illinois Open
 // Source Licenses. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
 #include "abort_message.h"
 
+#ifdef __BIONIC__
+#include <android/set_abort_message.h>
+#include <syslog.h>
+#endif
+
 #pragma GCC visibility push(hidden)
 
-#if __APPLE__ 
+#if __APPLE__
 #   if defined(__has_include) && __has_include(<CrashReporterClient.h>)
 #       define HAVE_CRASHREPORTERCLIENT_H 1
 #       include <CrashReporterClient.h>
 #   endif
 #endif
 
 __attribute__((visibility("hidden"), noreturn))
 void abort_message(const char* format, ...)
 {
     // write message to stderr
 #if __APPLE__
     fprintf(stderr, "libc++abi.dylib: ");
 #endif
     va_list list;
     va_start(list, format);
     vfprintf(stderr, format, list);
     va_end(list);
     fprintf(stderr, "\n");
-    
 #if __APPLE__ && HAVE_CRASHREPORTERCLIENT_H
     // record message in crash report
     char* buffer;
     va_list list2;
     va_start(list2, format);
     vasprintf(&buffer, format, list2);
     va_end(list2);
     CRSetCrashLogMessage(buffer);
+#elif __BIONIC__
+    char* buffer;
+    va_list list2;
+    va_start(list2, format);
+    vasprintf(&buffer, format, list2);
+    va_end(list2);
+
+    // Show error in tombstone.
+    android_set_abort_message(buffer);
+
+    // Show error in logcat.
+    openlog("libc++abi", 0, 0);
+    syslog(LOG_CRIT, "%s", buffer);
+    closelog();
 #endif
 
     abort();
 }
 
 #pragma GCC visibility pop