Remove unnecessary parameter from ff_thread_init() and fix behavior

thread_count passed to ff_thread_init() is only used to set AVCodecContext.
thread_count, and can be removed. Instead move it to the legacy implementation
of avcodec_thread_init().

This also fixes the problem that calling avcodec_thread_init() with pthreads
enabled did not set it since ff1efc52.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>

libavcodec/pthread.c

@@ -882,7 +882,7 @@ static void validate_thread_parameters(AVCodecContext *avctx)
     }
 }
 
-int ff_thread_init(AVCodecContext *avctx, int thread_count)
+int ff_thread_init(AVCodecContext *avctx)
 {
     if (avctx->thread_opaque) {
         av_log(avctx, AV_LOG_ERROR, "avcodec_thread_init is ignored after avcodec_open\n");

libavcodec/thread.h

@@ -108,7 +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);
+int ff_thread_init(AVCodecContext *s);
 void ff_thread_free(AVCodecContext *s);
 
 #endif /* AVCODEC_THREAD_H */

libavcodec/utils.c

@@ -539,7 +539,7 @@ int attribute_align_arg avcodec_open(AVCodecContext *avctx, AVCodec *codec)
     avctx->frame_number = 0;
 
     if (HAVE_THREADS && !avctx->thread_opaque) {
-        ret = ff_thread_init(avctx, avctx->thread_count);
+        ret = ff_thread_init(avctx);
         if (ret < 0) {
             goto free_and_end;
         }
@@ -1147,8 +1147,7 @@ int av_get_bits_per_sample_format(enum AVSampleFormat sample_fmt) {
 #endif
 
 #if !HAVE_THREADS
-int ff_thread_init(AVCodecContext *s, int thread_count){
-    s->thread_count = thread_count;
+int ff_thread_init(AVCodecContext *s){
     return -1;
 }
 #endif
@@ -1291,7 +1290,8 @@ void ff_thread_await_progress(AVFrame *f, int progress, int field)
 
 int avcodec_thread_init(AVCodecContext *s, int thread_count)
 {
-    return ff_thread_init(s, thread_count);
+    s->thread_count = thread_count;
+    return ff_thread_init(s);
 }
 
 void avcodec_thread_free(AVCodecContext *s)

libavcodec/w32thread.c

@@ -125,7 +125,7 @@ static int avcodec_thread_execute2(AVCodecContext *s, int (*func)(AVCodecContext
     avcodec_thread_execute(s, NULL, arg, ret, count, 0);
 }
 
-int ff_thread_init(AVCodecContext *s, int thread_count){
+int ff_thread_init(AVCodecContext *s){
     int i;
     ThreadContext *c;
     uint32_t threadid;
@@ -135,14 +135,13 @@ int ff_thread_init(AVCodecContext *s, int thread_count){
         return 0;
     }
 
-    s->thread_count= thread_count;
     s->active_thread_type= FF_THREAD_SLICE;
 
-    if (thread_count <= 1)
+    if (s->thread_count <= 1)
         return 0;
 
     assert(!s->thread_opaque);
-    c= av_mallocz(sizeof(ThreadContext)*thread_count);
+    c= av_mallocz(sizeof(ThreadContext)*s->thread_count);
     s->thread_opaque= c;
     if(!(c[0].work_sem = CreateSemaphore(NULL, 0, INT_MAX, NULL)))
         goto fail;
@@ -151,7 +150,7 @@ int ff_thread_init(AVCodecContext *s, int thread_count){
     if(!(c[0].done_sem = CreateSemaphore(NULL, 0, INT_MAX, NULL)))
         goto fail;
 
-    for(i=0; i<thread_count; i++){
+    for(i=0; i<s->thread_count; i++){
 //printf("init semaphors %d\n", i); fflush(stdout);
         c[i].avctx= s;
         c[i].work_sem = c[0].work_sem;