[FFmpeg-devel] [PATCH 02/12] Replace some variable-length arrays with av_malloc/free

[Mans Rullgard]

---
 libavcodec/aacenc.c           |    4 +++-
 libavcodec/error_resilience.c |    8 +++++---
 libavcodec/ratecontrol.c      |    7 +++++--
 libavcodec/resample2.c        |    6 +++++-
 4 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/libavcodec/aacenc.c b/libavcodec/aacenc.c
index 219a4c1..b40247a 100644
--- a/libavcodec/aacenc.c
+++ b/libavcodec/aacenc.c
@@ -488,7 +488,7 @@ static int aac_encode_frame(AVCodecContext *avctx,
     int i, j, chans, tag, start_ch;
     const uint8_t *chan_map = aac_chan_configs[avctx->channels-1];
     int chan_el_counter[4];
-    FFPsyWindowInfo windows[avctx->channels];
+    FFPsyWindowInfo *windows = av_malloc(avctx->channels * sizeof(*windows));
 
     if (s->last_frame)
         return 0;
@@ -612,6 +612,8 @@ static int aac_encode_frame(AVCodecContext *avctx,
         s->lambda = FFMIN(s->lambda, 65536.f);
     }
 
+    av_free(windows);
+
     if (!data)
         s->last_frame = 1;
     memcpy(s->samples, s->samples + 1024 * avctx->channels,
diff --git a/libavcodec/error_resilience.c b/libavcodec/error_resilience.c
index dc015b9..f343578 100644
--- a/libavcodec/error_resilience.c
+++ b/libavcodec/error_resilience.c
@@ -357,7 +357,7 @@ static void v_block_filter(MpegEncContext *s, uint8_t *dst, int w, int h, int st
 }
 
 static void guess_mv(MpegEncContext *s){
-    uint8_t fixed[s->mb_stride * s->mb_height];
+    uint8_t *fixed = av_malloc(s->mb_stride * s->mb_height);
 #define MV_FROZEN    3
 #define MV_CHANGED   2
 #define MV_UNCHANGED 1
@@ -405,7 +405,7 @@ static void guess_mv(MpegEncContext *s){
                 decode_mb(s, 0);
             }
         }
-        return;
+        goto end;
     }
 
     for(depth=0;; depth++){
@@ -606,7 +606,7 @@ score_sum+= best_score;
         }
 
         if(none_left)
-            return;
+            goto end;
 
         for(i=0; i<s->mb_num; i++){
             int mb_xy= s->mb_index2xy[i];
@@ -615,6 +615,8 @@ score_sum+= best_score;
         }
 //        printf(":"); fflush(stdout);
     }
+end:
+    av_free(fixed);
 }
 
 static int is_intra_more_likely(MpegEncContext *s){
diff --git a/libavcodec/ratecontrol.c b/libavcodec/ratecontrol.c
index 4261678..6a66f2f 100644
--- a/libavcodec/ratecontrol.c
+++ b/libavcodec/ratecontrol.c
@@ -537,8 +537,8 @@ static void adaptive_quantization(MpegEncContext *s, double q){
     const float border_masking = s->avctx->border_masking;
     float bits_sum= 0.0;
     float cplx_sum= 0.0;
-    float cplx_tab[s->mb_num];
-    float bits_tab[s->mb_num];
+    float *cplx_tab = av_malloc(s->mb_num * sizeof(*cplx_tab));
+    float *bits_tab = av_malloc(s->mb_num * sizeof(*bits_tab));
     const int qmin= s->avctx->mb_lmin;
     const int qmax= s->avctx->mb_lmax;
     Picture * const pic= &s->current_picture;
@@ -639,6 +639,9 @@ static void adaptive_quantization(MpegEncContext *s, double q){
 //printf("%2d%3d ", intq, ff_sqrt(s->mc_mb_var[i]));
         s->lambda_table[mb_xy]= intq;
     }
+
+    av_free(cplx_tab);
+    av_free(bits_tab);
 }
 
 void ff_get_2pass_fcode(MpegEncContext *s){
diff --git a/libavcodec/resample2.c b/libavcodec/resample2.c
index 45f41a1..53fe793 100644
--- a/libavcodec/resample2.c
+++ b/libavcodec/resample2.c
@@ -97,7 +97,8 @@ static double bessel(double x){
  */
 static void build_filter(FELEM *filter, double factor, int tap_count, int phase_count, int scale, int type){
     int ph, i;
-    double x, y, w, tab[tap_count];
+    double x, y, w;
+    double *tab = av_malloc(tap_count * sizeof(*tab));
     const int center= (tap_count-1)/2;
 
     /* if upsampling, only need to interpolate, no filter */
@@ -140,6 +141,9 @@ static void build_filter(FELEM *filter, double factor, int tap_count, int phase_
 #endif
         }
     }
+
+    av_free(tab);
+
 #if 0
     {
 #define LEN 1024
-- 
1.7.1