xwd: convert to bytestream2.

libavcodec/xwddec.c

@@ -45,43 +45,43 @@ static int xwd_decode_frame(AVCodecContext *avctx, void *data,
     uint32_t pixformat, pixdepth, bunit, bitorder, bpad;
     uint32_t rgb[3];
     uint8_t *ptr;
+    GetByteContext gb;
 
     if (buf_size < XWD_HEADER_SIZE)
         return AVERROR_INVALIDDATA;
 
-    header_size = bytestream_get_be32(&buf);
-    if (buf_size < header_size)
-        return AVERROR_INVALIDDATA;
+    bytestream2_init(&gb, buf, buf_size);
+    header_size = bytestream2_get_be32u(&gb);
 
-    version = bytestream_get_be32(&buf);
+    version = bytestream2_get_be32u(&gb);
     if (version != XWD_VERSION) {
         av_log(avctx, AV_LOG_ERROR, "unsupported version\n");
         return AVERROR_INVALIDDATA;
     }
 
-    if (header_size < XWD_HEADER_SIZE) {
+    if (buf_size < header_size || header_size < XWD_HEADER_SIZE) {
         av_log(avctx, AV_LOG_ERROR, "invalid header size\n");
         return AVERROR_INVALIDDATA;
     }
 
-    pixformat     = bytestream_get_be32(&buf);
-    pixdepth      = bytestream_get_be32(&buf);
-    avctx->width  = bytestream_get_be32(&buf);
-    avctx->height = bytestream_get_be32(&buf);
-    xoffset       = bytestream_get_be32(&buf);
-    be            = bytestream_get_be32(&buf);
-    bunit         = bytestream_get_be32(&buf);
-    bitorder      = bytestream_get_be32(&buf);
-    bpad          = bytestream_get_be32(&buf);
-    bpp           = bytestream_get_be32(&buf);
-    lsize         = bytestream_get_be32(&buf);
-    vclass        = bytestream_get_be32(&buf);
-    rgb[0]        = bytestream_get_be32(&buf);
-    rgb[1]        = bytestream_get_be32(&buf);
-    rgb[2]        = bytestream_get_be32(&buf);
-    buf          += 8;
-    ncolors       = bytestream_get_be32(&buf);
-    buf          += header_size - (XWD_HEADER_SIZE - 20);
+    pixformat     = bytestream2_get_be32u(&gb);
+    pixdepth      = bytestream2_get_be32u(&gb);
+    avctx->width  = bytestream2_get_be32u(&gb);
+    avctx->height = bytestream2_get_be32u(&gb);
+    xoffset       = bytestream2_get_be32u(&gb);
+    be            = bytestream2_get_be32u(&gb);
+    bunit         = bytestream2_get_be32u(&gb);
+    bitorder      = bytestream2_get_be32u(&gb);
+    bpad          = bytestream2_get_be32u(&gb);
+    bpp           = bytestream2_get_be32u(&gb);
+    lsize         = bytestream2_get_be32u(&gb);
+    vclass        = bytestream2_get_be32u(&gb);
+    rgb[0]        = bytestream2_get_be32u(&gb);
+    rgb[1]        = bytestream2_get_be32u(&gb);
+    rgb[2]        = bytestream2_get_be32u(&gb);
+    bytestream2_skipu(&gb, 8);
+    ncolors       = bytestream2_get_be32u(&gb);
+    bytestream2_skipu(&gb, header_size - (XWD_HEADER_SIZE - 20));
 
     av_log(avctx, AV_LOG_DEBUG, "pixformat %d, pixdepth %d, bunit %d, bitorder %d, bpad %d\n",
            pixformat, pixdepth, bunit, bitorder, bpad);
@@ -143,7 +143,7 @@ static int xwd_decode_frame(AVCodecContext *avctx, void *data,
         return AVERROR_INVALIDDATA;
     }
 
-    if (buf_size < header_size + ncolors * XWD_CMAP_SIZE + avctx->height * lsize) {
+    if (bytestream2_get_bytes_left(&gb) < ncolors * XWD_CMAP_SIZE + avctx->height * lsize) {
         av_log(avctx, AV_LOG_ERROR, "input buffer too small\n");
         return AVERROR_INVALIDDATA;
     }
@@ -192,7 +192,7 @@ static int xwd_decode_frame(AVCodecContext *avctx, void *data,
             else if (rgb[0] == 0xFF && rgb[1] == 0xFF00 && rgb[2] == 0xFF0000)
                 avctx->pix_fmt = be ? PIX_FMT_ABGR : PIX_FMT_RGBA;
         }
-        buf += ncolors * XWD_CMAP_SIZE;
+        bytestream2_skipu(&gb, ncolors * XWD_CMAP_SIZE);
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "invalid visual class\n");
@@ -222,11 +222,13 @@ static int xwd_decode_frame(AVCodecContext *avctx, void *data,
 
         for (i = 0; i < ncolors; i++) {
 
-            buf   += 4;  // skip colormap entry number
-            red    = *buf; buf += 2;
-            green  = *buf; buf += 2;
-            blue   = *buf; buf += 2;
-            buf   += 2;  // skip bitmask flag and padding
+            bytestream2_skipu(&gb, 4); // skip colormap entry number
+            red    = bytestream2_get_byteu(&gb);
+            bytestream2_skipu(&gb, 1);
+            green  = bytestream2_get_byteu(&gb);
+            bytestream2_skipu(&gb, 1);
+            blue   = bytestream2_get_byteu(&gb);
+            bytestream2_skipu(&gb, 3); // skip bitmask flag and padding
 
             dst[i] = red << 16 | green << 8 | blue;
         }
@@ -234,8 +236,8 @@ static int xwd_decode_frame(AVCodecContext *avctx, void *data,
 
     ptr = p->data[0];
     for (i = 0; i < avctx->height; i++) {
-        bytestream_get_buffer(&buf, ptr, rsize);
-        buf += lsize - rsize;
+        bytestream2_get_bufferu(&gb, ptr, rsize);
+        bytestream2_skipu(&gb, lsize - rsize);
         ptr += p->linesize[0];
     }