[FFmpeg-devel] [PATCH] aac: Make codec init run under ff_thread_once

[Derek Buitenhuis]

This makes AAC init threadsafe.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
---
This relies on the latest merge from Libav, which hasn't happened
yet.
---
 libavcodec/aacdec.c          |  2 ++
 libavcodec/aacdec_fixed.c    |  1 +
 libavcodec/aacdec_template.c | 80 +++++++++++++++++++++++++-------------------
 3 files changed, 49 insertions(+), 34 deletions(-)

diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c
index 837102f..f53803b 100644
--- a/libavcodec/aacdec.c
+++ b/libavcodec/aacdec.c
@@ -551,6 +551,7 @@ AVCodec ff_aac_decoder = {
         AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE
     },
     .capabilities    = AV_CODEC_CAP_CHANNEL_CONF | AV_CODEC_CAP_DR1,
+    .caps_internal   = FF_CODEC_CAP_INIT_THREADSAFE,
     .channel_layouts = aac_channel_layout,
     .flush = flush,
     .priv_class      = &aac_decoder_class,
@@ -575,6 +576,7 @@ AVCodec ff_aac_latm_decoder = {
         AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE
     },
     .capabilities    = AV_CODEC_CAP_CHANNEL_CONF | AV_CODEC_CAP_DR1,
+    .caps_internal   = FF_CODEC_CAP_INIT_THREADSAFE,
     .channel_layouts = aac_channel_layout,
     .flush = flush,
     .profiles        = profiles,
diff --git a/libavcodec/aacdec_fixed.c b/libavcodec/aacdec_fixed.c
index 875ef58..923fbe0 100644
--- a/libavcodec/aacdec_fixed.c
+++ b/libavcodec/aacdec_fixed.c
@@ -438,6 +438,7 @@ AVCodec ff_aac_fixed_decoder = {
         AV_SAMPLE_FMT_S32P, AV_SAMPLE_FMT_NONE
     },
     .capabilities    = AV_CODEC_CAP_CHANNEL_CONF | AV_CODEC_CAP_DR1,
+    .caps_internal   = FF_CODEC_CAP_INIT_THREADSAFE,
     .channel_layouts = aac_channel_layout,
     .flush = flush,
 };
diff --git a/libavcodec/aacdec_template.c b/libavcodec/aacdec_template.c
index c2d7d05..aabd3f0 100644
--- a/libavcodec/aacdec_template.c
+++ b/libavcodec/aacdec_template.c
@@ -89,6 +89,8 @@
            Parametric Stereo.
  */
 
+#include "libavutil/thread.h"
+
 static VLC vlc_scalefactors;
 static VLC vlc_spectral[11];
 
@@ -1063,11 +1065,55 @@ static void reset_predictor_group(PredictorState *ps, int group_num)
 
 static void aacdec_init(AACContext *ac);
 
+static av_cold void aac_static_table_init()
+{
+    AAC_INIT_VLC_STATIC( 0, 304);
+    AAC_INIT_VLC_STATIC( 1, 270);
+    AAC_INIT_VLC_STATIC( 2, 550);
+    AAC_INIT_VLC_STATIC( 3, 300);
+    AAC_INIT_VLC_STATIC( 4, 328);
+    AAC_INIT_VLC_STATIC( 5, 294);
+    AAC_INIT_VLC_STATIC( 6, 306);
+    AAC_INIT_VLC_STATIC( 7, 268);
+    AAC_INIT_VLC_STATIC( 8, 510);
+    AAC_INIT_VLC_STATIC( 9, 366);
+    AAC_INIT_VLC_STATIC(10, 462);
+
+    AAC_RENAME(ff_aac_sbr_init)();
+
+    ff_aac_tableinit();
+
+    INIT_VLC_STATIC(&vlc_scalefactors, 7,
+                    FF_ARRAY_ELEMS(ff_aac_scalefactor_code),
+                    ff_aac_scalefactor_bits,
+                    sizeof(ff_aac_scalefactor_bits[0]),
+                    sizeof(ff_aac_scalefactor_bits[0]),
+                    ff_aac_scalefactor_code,
+                    sizeof(ff_aac_scalefactor_code[0]),
+                    sizeof(ff_aac_scalefactor_code[0]),
+                    352);
+
+    // window initialization
+    AAC_RENAME(ff_kbd_window_init)(AAC_RENAME(ff_aac_kbd_long_1024), 4.0, 1024);
+    AAC_RENAME(ff_kbd_window_init)(AAC_RENAME(ff_aac_kbd_short_128), 6.0, 128);
+    AAC_RENAME(ff_init_ff_sine_windows)(10);
+    AAC_RENAME(ff_init_ff_sine_windows)( 9);
+    AAC_RENAME(ff_init_ff_sine_windows)( 7);
+
+    AAC_RENAME(cbrt_tableinit)();
+}
+
+static AVOnce aac_init = AV_ONCE_INIT;
+
 static av_cold int aac_decode_init(AVCodecContext *avctx)
 {
     AACContext *ac = avctx->priv_data;
     int ret;
 
+    ret = ff_thread_once(&aac_init, &aac_static_table_init);
+    if (ret != 0)
+        return AVERROR_UNKNOWN;
+
     ac->avctx = avctx;
     ac->oc[1].m4ac.sample_rate = avctx->sample_rate;
 
@@ -1119,20 +1165,6 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
         return AVERROR_INVALIDDATA;
     }
 
-    AAC_INIT_VLC_STATIC( 0, 304);
-    AAC_INIT_VLC_STATIC( 1, 270);
-    AAC_INIT_VLC_STATIC( 2, 550);
-    AAC_INIT_VLC_STATIC( 3, 300);
-    AAC_INIT_VLC_STATIC( 4, 328);
-    AAC_INIT_VLC_STATIC( 5, 294);
-    AAC_INIT_VLC_STATIC( 6, 306);
-    AAC_INIT_VLC_STATIC( 7, 268);
-    AAC_INIT_VLC_STATIC( 8, 510);
-    AAC_INIT_VLC_STATIC( 9, 366);
-    AAC_INIT_VLC_STATIC(10, 462);
-
-    AAC_RENAME(ff_aac_sbr_init)();
-
 #if USE_FIXED
     ac->fdsp = avpriv_alloc_fixed_dsp(avctx->flags & AV_CODEC_FLAG_BITEXACT);
 #else
@@ -1144,18 +1176,6 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
 
     ac->random_state = 0x1f2e3d4c;
 
-    ff_aac_tableinit();
-
-    INIT_VLC_STATIC(&vlc_scalefactors, 7,
-                    FF_ARRAY_ELEMS(ff_aac_scalefactor_code),
-                    ff_aac_scalefactor_bits,
-                    sizeof(ff_aac_scalefactor_bits[0]),
-                    sizeof(ff_aac_scalefactor_bits[0]),
-                    ff_aac_scalefactor_code,
-                    sizeof(ff_aac_scalefactor_code[0]),
-                    sizeof(ff_aac_scalefactor_code[0]),
-                    352);
-
     AAC_RENAME_32(ff_mdct_init)(&ac->mdct,       11, 1, 1.0 / RANGE15(1024.0));
     AAC_RENAME_32(ff_mdct_init)(&ac->mdct_ld,    10, 1, 1.0 / RANGE15(512.0));
     AAC_RENAME_32(ff_mdct_init)(&ac->mdct_small,  8, 1, 1.0 / RANGE15(128.0));
@@ -1165,14 +1185,6 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
     if (ret < 0)
         return ret;
 #endif
-    // window initialization
-    AAC_RENAME(ff_kbd_window_init)(AAC_RENAME(ff_aac_kbd_long_1024), 4.0, 1024);
-    AAC_RENAME(ff_kbd_window_init)(AAC_RENAME(ff_aac_kbd_short_128), 6.0, 128);
-    AAC_RENAME(ff_init_ff_sine_windows)(10);
-    AAC_RENAME(ff_init_ff_sine_windows)( 9);
-    AAC_RENAME(ff_init_ff_sine_windows)( 7);
-
-    AAC_RENAME(cbrt_tableinit)();
 
     return 0;
 }
-- 
1.8.3.1