From 5f635602cee8b7d4a79b0b51a0c7a060bb6575e2 Mon Sep 17 00:00:00 2001
From: vemax78 <devnull@localhost>
Date: Sun, 10 Nov 2013 22:10:40 +0100
Subject: [PATCH] Add debug information into mutex calls

---
 src/common/capwap_lock.c | 75 ++++++++++++++++++++++++++++++++++++----
 src/common/capwap_lock.h | 16 +++++++++
 2 files changed, 85 insertions(+), 6 deletions(-)

diff --git a/src/common/capwap_lock.c b/src/common/capwap_lock.c
index 039513b..a63bbd3 100644
--- a/src/common/capwap_lock.c
+++ b/src/common/capwap_lock.c
@@ -1,5 +1,6 @@
 #include "capwap.h"
 #include "capwap_lock.h"
+#include "capwap_logging.h"
 
 #ifndef CAPWAP_MULTITHREADING_ENABLE
 #error "Warning: multithreading is disabled\n"
@@ -17,23 +18,85 @@ int capwap_lock_init(capwap_lock_t* lock) {
 	return 1;
 }
 
+#ifdef DEBUG
+/* */
+void capwap_lock_destroy_debug(capwap_lock_t* lock, const char* file, const int line) {
+	int res;
+
+	ASSERT(lock != NULL);
+
+	res = pthread_mutex_trylock(&lock->mutex);
+	if (!res) {
+		pthread_mutex_unlock(&lock->mutex);
+	} else if (res == EINVAL) {
+		capwap_logging_debug("Attempt to destroy invalid mutex from '%s' (%d)", file, line);
+		capwap_backtrace_callstack();
+	} else if (res == EBUSY) {
+		capwap_logging_debug("Attempt to destroy locked mutex by '%s' (%d) from '%s' (%d)", lock->file, lock->line, file, line);
+		capwap_backtrace_callstack();
+	}
+
+	pthread_mutex_destroy(&lock->mutex);
+}
+
+/* */
+void capwap_lock_enter_debug(capwap_lock_t* lock, const char* file, const int line) {
+	int res;
+	time_t starttime;
+	time_t waittime;
+	time_t lasttime = 0;
+
+	ASSERT(lock != NULL);
+
+	/* */
+	starttime = time(NULL);
+
+	do {
+		res = pthread_mutex_trylock(&lock->mutex);
+		if (res == EBUSY) {
+			waittime = time(NULL) - starttime;
+			if (!(waittime % 5) && (waittime > lasttime)) {
+				lasttime = waittime;
+				capwap_logging_debug("Waited %d sec for mutex '%s' (%d) locked by '%s' (%d)", waittime, file, line, lock->file, lock->line);
+				capwap_backtrace_callstack();
+			}
+
+			usleep(200);
+		}
+	} while (res == EBUSY);
+
+	/* */
+	lock->file = (char*)file;
+	lock->line = (int)line;
+}
+
+/* */
+void capwap_lock_exit_debug(capwap_lock_t* lock, const char* file, const int line) {
+	ASSERT(lock != NULL);
+
+	/* */
+	lock->file = NULL;
+	lock->line = 0;
+
+	/* */
+	if (pthread_mutex_unlock(&lock->mutex)) {
+		capwap_logging_debug("Error releasing mutex '%s' (%d)", file, line);
+		capwap_backtrace_callstack();
+	}
+}
+#else
 /* */
 void capwap_lock_destroy(capwap_lock_t* lock) {
-	ASSERT(lock != NULL);
-	
 	pthread_mutex_destroy(&lock->mutex);
 }
 
 /* */
 void capwap_lock_enter(capwap_lock_t* lock) {
-	ASSERT(lock != NULL);
-	
 	pthread_mutex_lock(&lock->mutex);
 }
 
 /* */
 void capwap_lock_exit(capwap_lock_t* lock) {
-	ASSERT(lock != NULL);
-	
 	pthread_mutex_unlock(&lock->mutex);
 }
+#endif
diff --git a/src/common/capwap_lock.h b/src/common/capwap_lock.h
index cf4c1d8..a52c5f4 100644
--- a/src/common/capwap_lock.h
+++ b/src/common/capwap_lock.h
@@ -7,12 +7,28 @@
 
 typedef struct {
 	pthread_mutex_t mutex;
+#ifdef DEBUG
+	char* file;
+	int line;
+#endif
 } capwap_lock_t;
 
 int capwap_lock_init(capwap_lock_t* lock);
+
+#ifdef DEBUG
+#define capwap_lock_destroy(lock)						capwap_lock_destroy_debug(lock, __FILE__, __LINE__)
+void capwap_lock_destroy_debug(capwap_lock_t* lock, const char* file, const int line);
+
+#define capwap_lock_enter(lock)							capwap_lock_enter_debug(lock, __FILE__, __LINE__)
+void capwap_lock_enter_debug(capwap_lock_t* lock, const char* file, const int line);
+
+#define capwap_lock_exit(lock)							capwap_lock_exit_debug(lock, __FILE__, __LINE__)
+void capwap_lock_exit_debug(capwap_lock_t* lock, const char* file, const int line);
+#else
 void capwap_lock_destroy(capwap_lock_t* lock);
 void capwap_lock_enter(capwap_lock_t* lock);
 void capwap_lock_exit(capwap_lock_t* lock);
+#endif
 
 #endif /* CAPWAP_MULTITHREADING_ENABLE */