From 6492654d213236b394b22c71dd77827aa100a2fb Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jarkko=20P=C3=B6yry?= <jpoyry@google.com>
Date: Fri, 20 Mar 2015 15:29:47 -0700
Subject: [PATCH] Don't call exit() from signal handler.

Bug: 19517387
Change-Id: I58d60a54a9473d14b60f981682307338e30ba087
---
 framework/qphelper/qpCrashHandler.c | 17 ++++++++---------
 framework/qphelper/qpCrashHandler.h |  4 ++++
 framework/qphelper/qpDebugOut.c     | 30 +++++++++++++++++++++++-------
 3 files changed, 35 insertions(+), 16 deletions(-)

diff --git a/framework/qphelper/qpCrashHandler.c b/framework/qphelper/qpCrashHandler.c
index 114ca97..f78c0c7 100644
--- a/framework/qphelper/qpCrashHandler.c
+++ b/framework/qphelper/qpCrashHandler.c
@@ -373,12 +373,11 @@ void qpCrashHandler_writeCrashInfo (qpCrashHandler* handler, qpWriteCrashInfoFun
 
 #else /* posix / generic implementation */
 
-#if (DE_OS == DE_OS_UNIX) || (DE_OS == DE_OS_ANDROID) || (DE_OS == DE_OS_OSX) || (DE_OS == DE_OS_IOS)
-#	define USE_SIGNAL_HANDLER 1
+#if defined(QP_USE_SIGNAL_HANDLER)
 #	include <signal.h>
 #endif
 
-#if defined(USE_SIGNAL_HANDLER)
+#if defined(QP_USE_SIGNAL_HANDLER)
 
 typedef struct SignalInfo_s
 {
@@ -397,7 +396,7 @@ static const SignalInfo s_signals[] =
 	{ SIGPIPE,		QP_CRASHTYPE_OTHER,					"SIGPIPE"	}
 };
 
-#endif /* USE_SIGNAL_HANDLER */
+#endif /* QP_USE_SIGNAL_HANDLER */
 
 struct qpCrashHandler_s
 {
@@ -407,7 +406,7 @@ struct qpCrashHandler_s
 	qpCrashInfo				crashInfo;
 	int						crashSignal;
 
-#if defined(USE_SIGNAL_HANDLER)
+#if defined(QP_USE_SIGNAL_HANDLER)
 	struct sigaction		oldHandlers[DE_LENGTH_OF_ARRAY(s_signals)];
 #endif
 };
@@ -424,7 +423,7 @@ static void assertFailureCallback (const char* expr, const char* file, int line)
 		g_crashHandler->crashHandlerFunc(g_crashHandler, g_crashHandler->handlerUserPointer);
 }
 
-#if defined(USE_SIGNAL_HANDLER)
+#if defined(QP_USE_SIGNAL_HANDLER)
 
 static const SignalInfo* getSignalInfo (int sigNum)
 {
@@ -449,7 +448,7 @@ static void signalHandler (int sigNum)
 		g_crashHandler->crashHandlerFunc(g_crashHandler, g_crashHandler->handlerUserPointer);
 }
 
-#endif /* USE_SIGNAL_HANDLER */
+#endif /* QP_USE_SIGNAL_HANDLER */
 
 qpCrashHandler* qpCrashHandler_create (qpCrashHandlerFunc handlerFunc, void* userPointer)
 {
@@ -471,7 +470,7 @@ qpCrashHandler* qpCrashHandler_create (qpCrashHandlerFunc handlerFunc, void* use
 	/* DE_ASSERT callback. */
 	deSetAssertFailureCallback(assertFailureCallback);
 
-#if defined(USE_SIGNAL_HANDLER)
+#if defined(QP_USE_SIGNAL_HANDLER)
 	/* Register signal handlers. */
 	{
 		struct sigaction	action;
@@ -497,7 +496,7 @@ void qpCrashHandler_destroy (qpCrashHandler* handler)
 
 	deSetAssertFailureCallback(DE_NULL);
 
-#if defined(USE_SIGNAL_HANDLER)
+#if defined(QP_USE_SIGNAL_HANDLER)
 	/* Restore old handlers. */
 	{
 		int sigNdx;
diff --git a/framework/qphelper/qpCrashHandler.h b/framework/qphelper/qpCrashHandler.h
index 9bb12e0..9f8ad71 100644
--- a/framework/qphelper/qpCrashHandler.h
+++ b/framework/qphelper/qpCrashHandler.h
@@ -25,6 +25,10 @@
 
 #include "deDefs.h"
 
+#if (DE_OS == DE_OS_UNIX) || (DE_OS == DE_OS_ANDROID) || (DE_OS == DE_OS_OSX) || (DE_OS == DE_OS_IOS)
+#	define QP_USE_SIGNAL_HANDLER 1
+#endif
+
 typedef struct qpCrashHandler_s	qpCrashHandler;
 
 typedef void		(*qpCrashHandlerFunc)		(qpCrashHandler* crashHandler, void* userPtr);
diff --git a/framework/qphelper/qpDebugOut.c b/framework/qphelper/qpDebugOut.c
index e4a31f9..cb49ed8 100644
--- a/framework/qphelper/qpDebugOut.c
+++ b/framework/qphelper/qpDebugOut.c
@@ -23,6 +23,8 @@
 
 #include "qpDebugOut.h"
 
+#include "qpCrashHandler.h" /*!< for QP_USE_SIGNAL_HANDLER */
+
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -157,23 +159,37 @@ static void exitProcess (void)
 	TerminateProcess(curProc, -1);
 }
 
-#elif (DE_OS == DE_OS_IOS)
+#else
 
-#include "deThread.h"
+#if (DE_OS == DE_OS_IOS)
+#	include "deThread.h"	/*!< for deSleep() */
+#endif
+
+#if defined(QP_USE_SIGNAL_HANDLER)
+#	include <signal.h>
+#endif
 
 static void exitProcess (void)
 {
+#if (DE_OS == DE_OS_IOS)
 	/* Since tests are in the same process as execserver, we want to give it
 	   a chance to stream complete log data before terminating. */
 	deSleep(5000);
-	exit(-1);
-}
+#endif
 
-#else
+#if defined(QP_USE_SIGNAL_HANDLER)
+	/* QP_USE_SIGNAL_HANDLER defined, this means this function could have
+	   been called from a signal handler. Calling exit() inside a signal
+	   handler is not safe. */
 
-static void exitProcess (void)
-{
+	/* Flush all open FILES */
+	fflush(DE_NULL);
+
+	/* Kill without calling any _at_exit handlers as those might hang */
+	raise(SIGKILL);
+#else
 	exit(-1);
+#endif
 }
 
 #endif
-- 
2.7.4