safe logging

src/device.c

@@ -10,6 +10,7 @@
 #include <linux/videodev2.h>
 
 #include "tools.h"
+#include "logging.h"
 #include "device.h"
 
 

src/http.c

@@ -14,6 +14,7 @@
 #endif
 
 #include "tools.h"
+#include "logging.h"
 #include "stream.h"
 #include "http.h"
 
@@ -82,7 +83,6 @@ void http_server_loop(struct http_server_t *server) {
 }
 
 void http_server_loop_break(struct http_server_t *server) {
-	LOG_INFO("Stopping HTTP eventloop ...");
 	event_base_loopbreak(server->run->base);
 }
 

src/logging.h

@@ -0,0 +1,92 @@
+#pragma once
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <pthread.h>
+#include <time.h>
+#include <assert.h>
+
+#include "tools.h"
+
+
+unsigned log_level;
+pthread_mutex_t log_mutex;
+
+
+#define LOG_LEVEL_INFO		0
+#define LOG_LEVEL_VERBOSE	1
+#define LOG_LEVEL_PERF		2
+#define LOG_LEVEL_DEBUG		3
+
+
+#define LOGGING_INIT	assert(!pthread_mutex_init(&log_mutex, NULL))
+#define LOGGING_DESTROY	assert(!pthread_mutex_destroy(&log_mutex))
+
+#define LOGGING_LOCK	assert(!pthread_mutex_lock(&log_mutex))
+#define LOGGING_UNLOCK	assert(!pthread_mutex_unlock(&log_mutex))
+
+
+#define SEP_INFO(_x_ch) { \
+		LOGGING_LOCK; \
+		for (int _i = 0; _i < 80; ++_i) { \
+			putchar(_x_ch); \
+		} \
+		putchar('\n'); \
+		LOGGING_UNLOCK; \
+	}
+
+#define SEP_DEBUG(_x_ch) { \
+		if (log_level >= LOG_LEVEL_DEBUG) { \
+			SEP_INFO(_x_ch); \
+		} \
+	}
+
+#define LOG_ERROR(_x_msg, ...) { \
+		LOGGING_LOCK; \
+		printf("-- ERROR [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+		LOGGING_UNLOCK; \
+	}
+
+#define LOG_PERROR(_x_msg, ...) { \
+		char _buf[1024]; \
+		strerror_r(errno, _buf, 1024); \
+		LOGGING_LOCK; \
+		printf("-- ERROR [%.03Lf tid=%ld] -- " _x_msg ": %s\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__, _buf); \
+		LOGGING_UNLOCK; \
+	}
+
+#define LOG_INFO(_x_msg, ...) { \
+		LOGGING_LOCK; \
+		printf("-- INFO  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+		LOGGING_UNLOCK; \
+	}
+
+#define LOG_INFO_NOLOCK(_x_msg, ...) { \
+		printf("-- INFO  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+	}
+
+#define LOG_VERBOSE(_x_msg, ...) { \
+		if (log_level >= LOG_LEVEL_VERBOSE) { \
+			LOGGING_LOCK; \
+			printf("-- VERB  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+			LOGGING_UNLOCK; \
+		} \
+	}
+
+#define LOG_PERF(_x_msg, ...) { \
+		if (log_level >= LOG_LEVEL_PERF) { \
+			LOGGING_LOCK; \
+			printf("-- PERF  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+			LOGGING_UNLOCK; \
+		} \
+	}
+
+#define LOG_DEBUG(_x_msg, ...) { \
+		if (log_level >= LOG_LEVEL_DEBUG) { \
+			LOGGING_LOCK; \
+			printf("-- DEBUG [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); \
+			LOGGING_UNLOCK; \
+		} \
+	}

src/main.c

@@ -5,13 +5,13 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 #include <signal.h>
 #include <pthread.h>
 #include <getopt.h>
 
 #include "tools.h"
+#include "logging.h"
 #include "device.h"
 #include "stream.h"
 #include "http.h"
@@ -131,7 +131,7 @@ static void *_server_loop_thread(UNUSED void *_) {
 }
 
 static void _signal_handler(int signum) {
-	LOG_INFO("===== Stopping by %s =====", strsignal(signum));
+	LOG_INFO_NOLOCK("===== Stopping by %s =====", (signum == SIGTERM ? "SIGTERM" : "SIGINT"));
 	stream_loop_break(_ctx->stream);
 	http_server_loop_break(_ctx->server);
 }
@@ -161,6 +161,8 @@ int main(int argc, char *argv[]) {
 	struct http_server_t *server;
 	int exit_code = 0;
 
+	LOGGING_INIT;
+
 	dev = device_init();
 	stream = stream_init(dev);
 	server = http_server_init(stream);
@@ -187,5 +189,7 @@ int main(int argc, char *argv[]) {
 	http_server_destroy(server);
 	stream_destroy(stream);
 	device_destroy(dev);
+
+	LOGGING_DESTROY;
 	return abs(exit_code);
 }

src/stream.c

@@ -15,6 +15,7 @@
 #endif
 
 #include "tools.h"
+#include "logging.h"
 #include "device.h"
 #include "jpeg.h"
 #include "stream.h"

src/tools.h

@@ -2,7 +2,6 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 #include <errno.h>
 #include <math.h>
@@ -13,42 +12,7 @@
 #include <sys/types.h>
 #include <sys/syscall.h>
 
-
+#include "logging.h"
-unsigned log_level;
-
-
-#define LOG_LEVEL_INFO		0
-#define LOG_LEVEL_VERBOSE	1
-#define LOG_LEVEL_PERF		2
-#define LOG_LEVEL_DEBUG		3
-
-#define SEP_INFO(_x_ch) \
-	{ for (int _i = 0; _i < 80; ++_i) putchar(_x_ch); putchar('\n'); }
-
-#define SEP_DEBUG(_x_ch) \
-	{ if (log_level >= LOG_LEVEL_DEBUG) { SEP_INFO(_x_ch); } }
-
-#define LOG_ERROR(_x_msg, ...) \
-	printf("-- ERROR [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__)
-
-#define LOG_PERROR(_x_msg, ...) \
-	{ char _buf[1024]; strerror_r(errno, _buf, 1024); \
-	printf("-- ERROR [%.03Lf tid=%ld] -- " _x_msg ": %s\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__, _buf); }
-
-#define LOG_INFO(_x_msg, ...) \
-	printf("-- INFO  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__)
-
-#define LOG_VERBOSE(_x_msg, ...) \
-	{ if (log_level >= LOG_LEVEL_VERBOSE) \
-	printf("-- VERB  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); }
-
-#define LOG_PERF(_x_msg, ...) \
-	{ if (log_level >= LOG_LEVEL_PERF) \
-	printf("-- PERF  [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); }
-
-#define LOG_DEBUG(_x_msg, ...) \
-	{ if (log_level >= LOG_LEVEL_DEBUG) \
-	printf("-- DEBUG [%.03Lf tid=%ld] -- " _x_msg "\n", now_ms_ld(), syscall(SYS_gettid), ##__VA_ARGS__); }
 
 
 #define A_PTHREAD_CREATE(_tid, _func, _arg)	assert(!pthread_create(_tid, NULL, _func, _arg))
@@ -56,14 +20,13 @@ unsigned log_level;
 
 #define A_PTHREAD_M_INIT(_mutex)	assert(!pthread_mutex_init(_mutex, NULL))
 #define A_PTHREAD_M_DESTROY(_mutex)	assert(!pthread_mutex_destroy(_mutex))
-#define A_PTHREAD_M_LOCK(...)		assert(!pthread_mutex_lock(__VA_ARGS__))
+#define A_PTHREAD_M_LOCK(_mutex)	assert(!pthread_mutex_lock(_mutex))
-#define A_PTHREAD_M_UNLOCK(...)		assert(!pthread_mutex_unlock(__VA_ARGS__))
+#define A_PTHREAD_M_UNLOCK(_mutex)	assert(!pthread_mutex_unlock(_mutex))
 
 #define A_PTHREAD_C_INIT(_cond)		assert(!pthread_cond_init(_cond, NULL))
 #define A_PTHREAD_C_DESTROY(_cond)	assert(!pthread_cond_destroy(_cond))
 #define A_PTHREAD_C_SIGNAL(...)		assert(!pthread_cond_signal(__VA_ARGS__))
-#define A_PTHREAD_C_WAIT_TRUE(_var, _cond, _mutex) \
+#define A_PTHREAD_C_WAIT_TRUE(_var, _cond, _mutex) { while(!_var) assert(!pthread_cond_wait(_cond, _mutex)); }
-	{ while(!_var) assert(!pthread_cond_wait(_cond, _mutex)); }
 
 
 #define A_CALLOC(_dest, _nmemb)		assert((_dest = calloc(_nmemb, sizeof(*(_dest)))))