cosmetics: Write NULL pointer equality checks more compactly

[ffmpeg] / libavcodec / dxa.c

diff --git a/libavcodec/dxa.c b/libavcodec/dxa.c
index 9e7f453b081069691ba7ebc9f11b71fbe34a2f94..989fcb965bf73f3e3c39a2dcfe2f977a0aa50119 100644 (file)
--- a/libavcodec/dxa.c
+++ b/libavcodec/dxa.c
@@ -38,7 +38,7 @@
  * Decoder context
  */
 typedef struct DxaDecContext {
-    AVFrame prev;
+    AVFrame *prev;
 
     int dsize;
     uint8_t *decomp_buf;
@@ -226,7 +226,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
 
     outptr = frame->data[0];
     srcptr = c->decomp_buf;
-    tmpptr = c->prev.data[0];
+    tmpptr = c->prev->data[0];
     stride = frame->linesize[0];
 
     if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L')
@@ -243,8 +243,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
     case -1:
         frame->key_frame = 0;
         frame->pict_type = AV_PICTURE_TYPE_P;
-        if(c->prev.data[0])
-            memcpy(frame->data[0], c->prev.data[0], frame->linesize[0] * avctx->height);
+        if (c->prev->data[0])
+            memcpy(frame->data[0], c->prev->data[0], frame->linesize[0] * avctx->height);
         else{ // Should happen only when first frame is 'NULL'
             memset(frame->data[0], 0, frame->linesize[0] * avctx->height);
             frame->key_frame = 1;
@@ -252,35 +252,44 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
         }
         break;
     case 2:
-    case 3:
     case 4:
-    case 5:
-        frame->key_frame = !(compr & 1);
-        frame->pict_type = (compr & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
-        for(j = 0; j < avctx->height; j++){
-            if(compr & 1){
-                for(i = 0; i < avctx->width; i++)
-                    outptr[i] = srcptr[i] ^ tmpptr[i];
-                tmpptr += stride;
-            }else
+        frame->key_frame = 1;
+        frame->pict_type = AV_PICTURE_TYPE_I;
+        for (j = 0; j < avctx->height; j++) {
                 memcpy(outptr, srcptr, avctx->width);
             outptr += stride;
             srcptr += avctx->width;
         }
         break;
+    case 3:
+    case 5:
+        if (!tmpptr) {
+            av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
+            return AVERROR_INVALIDDATA;
+        }
+        frame->key_frame = 0;
+        frame->pict_type = AV_PICTURE_TYPE_P;
+        for (j = 0; j < avctx->height; j++) {
+            for (i = 0; i < avctx->width; i++)
+                outptr[i] = srcptr[i] ^ tmpptr[i];
+            tmpptr += stride;
+            outptr += stride;
+            srcptr += avctx->width;
+        }
+        break;
     case 12: // ScummVM coding
     case 13:
         frame->key_frame = 0;
         frame->pict_type = AV_PICTURE_TYPE_P;
-        decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev.data[0]);
+        decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev->data[0]);
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]);
         return AVERROR_INVALIDDATA;
     }
 
-    av_frame_unref(&c->prev);
-    if ((ret = av_frame_ref(&c->prev, frame)) < 0)
+    av_frame_unref(c->prev);
+    if ((ret = av_frame_ref(c->prev, frame)) < 0)
         return ret;
 
     *got_frame = 1;
@@ -293,10 +302,14 @@ static av_cold int decode_init(AVCodecContext *avctx)
 {
     DxaDecContext * const c = avctx->priv_data;
 
+    c->prev = av_frame_alloc();
+    if (!c->prev)
+        return AVERROR(ENOMEM);
+
     avctx->pix_fmt = AV_PIX_FMT_PAL8;
 
     c->dsize = avctx->width * avctx->height * 2;
-    if((c->decomp_buf = av_malloc(c->dsize)) == NULL) {
+    if (!(c->decomp_buf = av_malloc(c->dsize))) {
         av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
         return AVERROR(ENOMEM);
     }
@@ -309,13 +322,14 @@ static av_cold int decode_end(AVCodecContext *avctx)
     DxaDecContext * const c = avctx->priv_data;
 
     av_freep(&c->decomp_buf);
-    av_frame_unref(&c->prev);
+    av_frame_free(&c->prev);
 
     return 0;
 }
 
 AVCodec ff_dxa_decoder = {
     .name           = "dxa",
+    .long_name      = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_DXA,
     .priv_data_size = sizeof(DxaDecContext),
@@ -323,5 +337,4 @@ AVCodec ff_dxa_decoder = {
     .close          = decode_end,
     .decode         = decode_frame,
     .capabilities   = CODEC_CAP_DR1,
-    .long_name      = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
 };