From: Helge Norberg <helge.norberg@svt.se>
Date: Mon, 10 Apr 2017 15:28:02 +0000 (+0200)
Subject: [logging] Made FFmpeg logging callback thread-safe by using thread-local storage... 
X-Git-Tag: 2.1.0_Beta2~3
X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=f488fb61c318535ea62540a1429616c08f2a3df3;p=casparcg

[logging] Made FFmpeg logging callback thread-safe by using thread-local storage for state that is carried between multiple calls
---

diff --git a/modules/ffmpeg/ffmpeg.cpp b/modules/ffmpeg/ffmpeg.cpp
index cece1f6bf..ea7f73741 100644
--- a/modules/ffmpeg/ffmpeg.cpp
+++ b/modules/ffmpeg/ffmpeg.cpp
@@ -109,7 +109,15 @@ static void sanitize(uint8_t *line)
 
 void log_callback(void* ptr, int level, const char* fmt, va_list vl)
 {
-	static int print_prefix=1;
+	static boost::thread_specific_ptr<bool> print_prefix_tss;
+	auto print_prefix = print_prefix_tss.get();
+
+	if (!print_prefix)
+	{
+		print_prefix = new bool(true);
+		print_prefix_tss.reset(print_prefix);
+	}
+
 	char line[1024];
 	AVClass* avc= ptr ? *(AVClass**)ptr : NULL;
 	if (level > AV_LOG_DEBUG)
@@ -117,7 +125,7 @@ void log_callback(void* ptr, int level, const char* fmt, va_list vl)
 	line[0]=0;
 
 #undef fprintf
-	if(print_prefix && avc)
+	if(*print_prefix && avc)
 	{
 		if (avc->parent_log_context_offset)
 		{
@@ -130,7 +138,7 @@ void log_callback(void* ptr, int level, const char* fmt, va_list vl)
 
 	std::vsnprintf(line + strlen(line), sizeof(line) - strlen(line), fmt, vl);
 
-	print_prefix = strlen(line) && line[strlen(line)-1] == '\n';
+	*print_prefix = strlen(line) && line[strlen(line)-1] == '\n';
 
 	sanitize((uint8_t*)line);