[FFmpeg-devel] [PATCH 1/6] avformat/utils: Use static mutexes instead of ff_lock_avformat()

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Fri May 17 18:23:05 EEST 2024


Its existence is a remnant of (libavcodec's) lock-manager API
which has been removed in a04c2c707de2ce850f79870e84ac9d7ec7aa9143.
There is no need to use the same lock for avisynth, chromaprint
or tls, so switch to ordinary static mutexes instead.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavformat/avisynth.c    | 15 +++++++++------
 libavformat/chromaprint.c | 12 +++++++-----
 libavformat/internal.h    |  3 ---
 libavformat/tls_gnutls.c  | 16 +++++++---------
 libavformat/tls_openssl.c | 17 +++++++----------
 libavformat/utils.c       | 13 -------------
 6 files changed, 30 insertions(+), 46 deletions(-)

diff --git a/libavformat/avisynth.c b/libavformat/avisynth.c
index 1709bf4051..625bdf7e3a 100644
--- a/libavformat/avisynth.c
+++ b/libavformat/avisynth.c
@@ -23,6 +23,7 @@
 #include "libavutil/internal.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
+#include "libavutil/thread.h"
 
 #include "avformat.h"
 #include "demux.h"
@@ -130,6 +131,8 @@ static const int avs_planes_yuva[4]   = { AVS_PLANAR_Y, AVS_PLANAR_U,
 static const int avs_planes_rgba[4]   = { AVS_PLANAR_G, AVS_PLANAR_B,
                                           AVS_PLANAR_R, AVS_PLANAR_A };
 
+static AVMutex avisynth_mutex = AV_MUTEX_INITIALIZER;
+
 /* A conflict between C++ global objects, atexit, and dynamic loading requires
  * us to register our own atexit handler to prevent double freeing. */
 static AviSynthLibrary avs_library;
@@ -1083,15 +1086,15 @@ static av_cold int avisynth_read_header(AVFormatContext *s)
     int ret;
 
     // Calling library must implement a lock for thread-safe opens.
-    if (ret = ff_lock_avformat())
-        return ret;
+    if (ff_mutex_lock(&avisynth_mutex))
+        return AVERROR_UNKNOWN;
 
     if (ret = avisynth_open_file(s)) {
-        ff_unlock_avformat();
+        ff_mutex_unlock(&avisynth_mutex);
         return ret;
     }
 
-    ff_unlock_avformat();
+    ff_mutex_unlock(&avisynth_mutex);
     return 0;
 }
 
@@ -1127,11 +1130,11 @@ static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)
 
 static av_cold int avisynth_read_close(AVFormatContext *s)
 {
-    if (ff_lock_avformat())
+    if (ff_mutex_lock(&avisynth_mutex))
         return AVERROR_UNKNOWN;
 
     avisynth_context_destroy(s->priv_data);
-    ff_unlock_avformat();
+    ff_mutex_unlock(&avisynth_mutex);
     return 0;
 }
 
diff --git a/libavformat/chromaprint.c b/libavformat/chromaprint.c
index 1cdca47ea5..eae233a651 100644
--- a/libavformat/chromaprint.c
+++ b/libavformat/chromaprint.c
@@ -20,15 +20,17 @@
  */
 
 #include "avformat.h"
-#include "internal.h"
 #include "mux.h"
 #include "libavutil/opt.h"
+#include "libavutil/thread.h"
 #include <chromaprint.h>
 
 #define CPR_VERSION_INT AV_VERSION_INT(CHROMAPRINT_VERSION_MAJOR, \
                                        CHROMAPRINT_VERSION_MINOR, \
                                        CHROMAPRINT_VERSION_PATCH)
 
+static AVMutex chromaprint_mutex = AV_MUTEX_INITIALIZER;
+
 typedef enum FingerprintFormat {
     FINGERPRINT_RAW,
     FINGERPRINT_COMPRESSED,
@@ -52,9 +54,9 @@ static void deinit(AVFormatContext *s)
     ChromaprintMuxContext *const cpr = s->priv_data;
 
     if (cpr->ctx) {
-        ff_lock_avformat();
+        ff_mutex_lock(&chromaprint_mutex);
         chromaprint_free(cpr->ctx);
-        ff_unlock_avformat();
+        ff_mutex_unlock(&chromaprint_mutex);
     }
 }
 
@@ -63,9 +65,9 @@ static av_cold int init(AVFormatContext *s)
     ChromaprintMuxContext *cpr = s->priv_data;
     AVStream *st;
 
-    ff_lock_avformat();
+    ff_mutex_lock(&chromaprint_mutex);
     cpr->ctx = chromaprint_new(cpr->algorithm);
-    ff_unlock_avformat();
+    ff_mutex_unlock(&chromaprint_mutex);
 
     if (!cpr->ctx) {
         av_log(s, AV_LOG_ERROR, "Failed to create chromaprint context.\n");
diff --git a/libavformat/internal.h b/libavformat/internal.h
index 7f3d1c0086..6bad4fd119 100644
--- a/libavformat/internal.h
+++ b/libavformat/internal.h
@@ -727,9 +727,6 @@ struct AVBPrint;
  */
 int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf);
 
-int ff_lock_avformat(void);
-int ff_unlock_avformat(void);
-
 /**
  * Set AVFormatContext url field to the provided pointer. The pointer must
  * point to a valid string. The existing url field is freed if necessary. Also
diff --git a/libavformat/tls_gnutls.c b/libavformat/tls_gnutls.c
index 2ab38a199b..df251ad79c 100644
--- a/libavformat/tls_gnutls.c
+++ b/libavformat/tls_gnutls.c
@@ -25,15 +25,12 @@
 #include <gnutls/x509.h>
 
 #include "avformat.h"
-#include "internal.h"
 #include "network.h"
 #include "os_support.h"
 #include "url.h"
 #include "tls.h"
-#include "libavcodec/internal.h"
-#include "libavutil/avstring.h"
 #include "libavutil/opt.h"
-#include "libavutil/parseutils.h"
+#include "libavutil/thread.h"
 
 #ifndef GNUTLS_VERSION_NUMBER
 #define GNUTLS_VERSION_NUMBER LIBGNUTLS_VERSION_NUMBER
@@ -41,7 +38,6 @@
 
 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER <= 0x020b00
 #include <gcrypt.h>
-#include "libavutil/thread.h"
 GCRY_THREAD_OPTION_PTHREAD_IMPL;
 #endif
 
@@ -54,22 +50,24 @@ typedef struct TLSContext {
     int io_err;
 } TLSContext;
 
+static AVMutex gnutls_mutex = AV_MUTEX_INITIALIZER;
+
 void ff_gnutls_init(void)
 {
-    ff_lock_avformat();
+    ff_mutex_lock(&gnutls_mutex);
 #if HAVE_THREADS && GNUTLS_VERSION_NUMBER < 0x020b00
     if (gcry_control(GCRYCTL_ANY_INITIALIZATION_P) == 0)
         gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
 #endif
     gnutls_global_init();
-    ff_unlock_avformat();
+    ff_mutex_unlock(&gnutls_mutex);
 }
 
 void ff_gnutls_deinit(void)
 {
-    ff_lock_avformat();
+    ff_mutex_lock(&gnutls_mutex);
     gnutls_global_deinit();
-    ff_unlock_avformat();
+    ff_mutex_unlock(&gnutls_mutex);
 }
 
 static int print_tls_error(URLContext *h, int ret)
diff --git a/libavformat/tls_openssl.c b/libavformat/tls_openssl.c
index b875be32f0..89d7c6e1ea 100644
--- a/libavformat/tls_openssl.c
+++ b/libavformat/tls_openssl.c
@@ -19,17 +19,12 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "avformat.h"
-#include "internal.h"
 #include "network.h"
 #include "os_support.h"
 #include "url.h"
 #include "tls.h"
-#include "libavutil/avstring.h"
-#include "libavutil/avutil.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
-#include "libavutil/parseutils.h"
 #include "libavutil/thread.h"
 
 #include <openssl/bio.h>
@@ -49,6 +44,8 @@ typedef struct TLSContext {
     int io_err;
 } TLSContext;
 
+static AVMutex openssl_mutex = AV_MUTEX_INITIALIZER;
+
 #if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
 #include <openssl/crypto.h>
 pthread_mutex_t *openssl_mutexes;
@@ -69,7 +66,7 @@ static unsigned long openssl_thread_id(void)
 
 int ff_openssl_init(void)
 {
-    ff_lock_avformat();
+    ff_mutex_lock(&openssl_mutex);
     if (!openssl_init) {
         /* OpenSSL 1.0.2 or below, then you would use SSL_library_init. If you are
          * using OpenSSL 1.1.0 or above, then the library will initialize
@@ -85,7 +82,7 @@ int ff_openssl_init(void)
             int i;
             openssl_mutexes = av_malloc_array(sizeof(pthread_mutex_t), CRYPTO_num_locks());
             if (!openssl_mutexes) {
-                ff_unlock_avformat();
+                ff_mutex_unlock(&openssl_mutex);
                 return AVERROR(ENOMEM);
             }
 
@@ -99,14 +96,14 @@ int ff_openssl_init(void)
 #endif
     }
     openssl_init++;
-    ff_unlock_avformat();
+    ff_mutex_unlock(&openssl_mutex);
 
     return 0;
 }
 
 void ff_openssl_deinit(void)
 {
-    ff_lock_avformat();
+    ff_mutex_lock(&openssl_mutex);
     openssl_init--;
     if (!openssl_init) {
 #if HAVE_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L
@@ -119,7 +116,7 @@ void ff_openssl_deinit(void)
         }
 #endif
     }
-    ff_unlock_avformat();
+    ff_mutex_unlock(&openssl_mutex);
 }
 
 static int print_tls_error(URLContext *h, int ret)
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 4dded7aea4..e9ded627ad 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -27,7 +27,6 @@
 #include "libavutil/bprint.h"
 #include "libavutil/internal.h"
 #include "libavutil/mem.h"
-#include "libavutil/thread.h"
 #include "libavutil/time.h"
 
 #include "libavcodec/internal.h"
@@ -40,23 +39,11 @@
 #endif
 #include "os_support.h"
 
-static AVMutex avformat_mutex = AV_MUTEX_INITIALIZER;
-
 /**
  * @file
  * various utility functions for use within FFmpeg
  */
 
-int ff_lock_avformat(void)
-{
-    return ff_mutex_lock(&avformat_mutex) ? -1 : 0;
-}
-
-int ff_unlock_avformat(void)
-{
-    return ff_mutex_unlock(&avformat_mutex) ? -1 : 0;
-}
-
 /* an arbitrarily chosen "sane" max packet size -- 50M */
 #define SANE_CHUNK_SIZE (50000000)
 
-- 
2.40.1



More information about the ffmpeg-devel mailing list