Deprecate avcodec_thread_init()

As a side effect of the last commit, avcodec_open() now calls it automatically,
so there is no longer any need for clients to call it.
Instead they should set AVCodecContext.thread_count.

avcodec_thread_free() is deprecated, and will be removed from avcodec.h at the
next MAJOR libavcodec bump.

Rename the functions to ff_thread_init/free, since they are now internal.
Wrappers are provided to maintain API compatibility.

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
(cherry picked from commit c0b102ca03fe92250f1ce620aec3836f529fc1d6)

doc/APIchanges

@@ -13,6 +13,10 @@ libavutil:   2009-03-08
 
 API changes, most recent first:
 
+2011-02-09 - XXXXXXX - lavc 52.112.0 - avcodec_thread_init()
+  Deprecate avcodec_thread_init()/avcodec_thread_free() use; instead
+  set thread_count before calling avcodec_open.
+
 2011-02-09 - 778b08a - lavc 52.111.0 - threading API
   Add CODEC_CAP_FRAME_THREADS with new restrictions on get_buffer()/
   release_buffer()/draw_horiz_band() callbacks for appropriate codecs.

ffmpeg.c

@@ -707,11 +707,6 @@ static int read_ffserver_streams(AVFormatContext *s, const char *filename)
                 choose_pixel_fmt(st, codec);
         }
 
-        if(!st->codec->thread_count)
-            st->codec->thread_count = 1;
-        if(st->codec->thread_count>1)
-            avcodec_thread_init(st->codec, st->codec->thread_count);
-
         if(st->codec->flags & CODEC_FLAG_BITEXACT)
             nopts = 1;
 
@@ -3248,7 +3243,7 @@ static void opt_input_file(const char *filename)
     for(i=0;i<ic->nb_streams;i++) {
         AVStream *st = ic->streams[i];
         AVCodecContext *dec = st->codec;
-        avcodec_thread_init(dec, thread_count);
+        dec->thread_count = thread_count;
         input_codecs = grow_array(input_codecs, sizeof(*input_codecs), &nb_input_codecs, nb_input_codecs + 1);
         switch (dec->codec_type) {
         case AVMEDIA_TYPE_AUDIO:
@@ -3406,7 +3401,7 @@ static void new_video_stream(AVFormatContext *oc, int file_idx)
     ost->bitstream_filters = video_bitstream_filters;
     video_bitstream_filters= NULL;
 
-    avcodec_thread_init(st->codec, thread_count);
+    st->codec->thread_count= thread_count;
 
     video_enc = st->codec;
 
@@ -3553,7 +3548,7 @@ static void new_audio_stream(AVFormatContext *oc, int file_idx)
     ost->bitstream_filters = audio_bitstream_filters;
     audio_bitstream_filters= NULL;
 
-    avcodec_thread_init(st->codec, thread_count);
+    st->codec->thread_count= thread_count;
 
     audio_enc = st->codec;
     audio_enc->codec_type = AVMEDIA_TYPE_AUDIO;

ffplay.c

@@ -2257,7 +2257,7 @@ static int stream_component_open(VideoState *is, int stream_index)
     avctx->skip_loop_filter= skip_loop_filter;
     avctx->error_recognition= error_recognition;
     avctx->error_concealment= error_concealment;
-    avcodec_thread_init(avctx, thread_count);
+    avctx->thread_count= thread_count;
 
     set_context_opts(avctx, avcodec_opts[avctx->codec_type], 0, codec);
 

libavcodec/avcodec.h

@@ -32,7 +32,7 @@
 #include "libavutil/cpu.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 52
-#define LIBAVCODEC_VERSION_MINOR 111
+#define LIBAVCODEC_VERSION_MINOR 112
 #define LIBAVCODEC_VERSION_MICRO  0
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
@@ -3656,8 +3656,14 @@ int avcodec_check_dimensions(void *av_log_ctx, unsigned int w, unsigned int h);
 
 enum PixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum PixelFormat * fmt);
 
+#if LIBAVCODEC_VERSION_MAJOR < 53
+/**
+ * @deprecated Set s->thread_count before calling avcodec_open() instead of calling this.
+ */
+attribute_deprecated
 int avcodec_thread_init(AVCodecContext *s, int thread_count);
 void avcodec_thread_free(AVCodecContext *s);
+#endif
 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
 //FIXME func typedef

libavcodec/pthread.c

@@ -256,7 +256,7 @@ static int thread_init(AVCodecContext *avctx)
         if(pthread_create(&c->workers[i], NULL, worker, avctx)) {
            avctx->thread_count = i;
            pthread_mutex_unlock(&c->current_job_lock);
-           avcodec_thread_free(avctx);
+           ff_thread_free(avctx);
            return -1;
         }
     }
@@ -870,7 +870,7 @@ static void validate_thread_parameters(AVCodecContext *avctx)
     }
 }
 
-int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
+int ff_thread_init(AVCodecContext *avctx, int thread_count)
 {
     if (avctx->thread_opaque) {
         av_log(avctx, AV_LOG_ERROR, "avcodec_thread_init is ignored after avcodec_open\n");
@@ -891,7 +891,7 @@ int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
     return 0;
 }
 
-void avcodec_thread_free(AVCodecContext *avctx)
+void ff_thread_free(AVCodecContext *avctx)
 {
     if (avctx->active_thread_type&FF_THREAD_FRAME)
         frame_thread_free(avctx, avctx->thread_count);

libavcodec/thread.h

@@ -108,4 +108,7 @@ int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f);
  */
 void ff_thread_release_buffer(AVCodecContext *avctx, AVFrame *f);
 
+int ff_thread_init(AVCodecContext *s, int thread_count);
+void ff_thread_free(AVCodecContext *s);
+
 #endif /* AVCODEC_THREAD_H */

libavcodec/utils.c

@@ -540,7 +540,7 @@ int attribute_align_arg avcodec_open(AVCodecContext *avctx, AVCodec *codec)
     avctx->frame_number = 0;
 
     if (HAVE_THREADS && !avctx->thread_opaque) {
-        ret = avcodec_thread_init(avctx, avctx->thread_count);
+        ret = ff_thread_init(avctx, avctx->thread_count);
         if (ret < 0) {
             goto free_and_end;
         }
@@ -819,7 +819,7 @@ av_cold int avcodec_close(AVCodecContext *avctx)
     }
 
     if (HAVE_THREADS && avctx->thread_opaque)
-        avcodec_thread_free(avctx);
+        ff_thread_free(avctx);
     if (avctx->codec && avctx->codec->close)
         avctx->codec->close(avctx);
     avcodec_default_free_buffers(avctx);
@@ -1180,7 +1180,7 @@ int av_get_bits_per_sample_format(enum AVSampleFormat sample_fmt) {
 #endif
 
 #if !HAVE_THREADS
-int avcodec_thread_init(AVCodecContext *s, int thread_count){
+int ff_thread_init(AVCodecContext *s, int thread_count){
     s->thread_count = thread_count;
     return -1;
 }
@@ -1319,3 +1319,17 @@ void ff_thread_await_progress(AVFrame *f, int progress, int field)
 }
 
 #endif
+
+#if LIBAVCODEC_VERSION_MAJOR < 53
+
+int avcodec_thread_init(AVCodecContext *s, int thread_count)
+{
+    return ff_thread_init(s, thread_count);
+}
+
+void avcodec_thread_free(AVCodecContext *s)
+{
+    return ff_thread_free(s);
+}
+
+#endif

libavcodec/w32thread.c

@@ -69,10 +69,10 @@ static unsigned WINAPI attribute_align_arg thread_func(void *v){
 }
 
 /**
- * Free what has been allocated by avcodec_thread_init().
+ * Free what has been allocated by ff_thread_init().
  * Must be called after decoding has finished, especially do not call while avcodec_thread_execute() is running.
  */
-void avcodec_thread_free(AVCodecContext *s){
+void ff_thread_free(AVCodecContext *s){
     ThreadContext *c= s->thread_opaque;
     int i;
 
@@ -124,7 +124,7 @@ static int avcodec_thread_execute2(AVCodecContext *s, int (*func)(AVCodecContext
     avcodec_thread_execute(s, NULL, arg, ret, count, 0);
 }
 
-int avcodec_thread_init(AVCodecContext *s, int thread_count){
+int ff_thread_init(AVCodecContext *s, int thread_count){
     int i;
     ThreadContext *c;
     uint32_t threadid;
@@ -169,6 +169,6 @@ int avcodec_thread_init(AVCodecContext *s, int thread_count){
 
     return 0;
 fail:
-    avcodec_thread_free(s);
+    ff_thread_free(s);
     return -1;
 }