avcodec/prosumer: Remove unneeded ()

[ffmpeg] / libavcodec / scpr.c

diff --git a/libavcodec/scpr.c b/libavcodec/scpr.c
index ad6073dbf0118d399b755c3e2d66454b8058947e..e41fbbec13c7b9051f6589125011a38b6678dd3b 100644 (file)
--- a/libavcodec/scpr.c
+++ b/libavcodec/scpr.c
@@ -136,7 +136,7 @@ static int decode(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigned
     rc->range *= freq;
 
     while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
-        unsigned byte = bytestream2_get_byte(gb);
+        unsigned byte = bytestream2_get_byteu(gb);
         rc->code = (rc->code << 8) | byte;
         rc->range <<= 8;
     }
@@ -172,7 +172,7 @@ static int decode0(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigne
     rc->range = rc->range * (uint64_t)(freq + cumFreq) / total_freq - (t + 1);
 
     while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
-        unsigned byte = bytestream2_get_byte(gb);
+        unsigned byte = bytestream2_get_byteu(gb);
         rc->code = (rc->code << 8) | byte;
         rc->code1 <<= 8;
         rc->range <<= 8;
@@ -211,6 +211,10 @@ static int decode_value(SCPRContext *s, unsigned *cnt, unsigned maxc, unsigned s
             break;
         c++;
     }
+
+    if (c >= maxc)
+        return AVERROR_INVALIDDATA;
+
     if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
         return ret;
 
@@ -293,14 +297,41 @@ static int decode_unit(SCPRContext *s, PixelModel *pixel, unsigned step, unsigne
     return 0;
 }
 
+static int decode_units(SCPRContext *s, unsigned *r, unsigned *g, unsigned *b,
+                        int *cx, int *cx1)
+{
+    const int cxshift = s->cxshift;
+    int ret;
+
+    ret = decode_unit(s, &s->pixel_model[0][*cx + *cx1], 400, r);
+    if (ret < 0)
+        return ret;
+
+    *cx1 = (*cx << 6) & 0xFC0;
+    *cx = *r >> cxshift;
+    ret = decode_unit(s, &s->pixel_model[1][*cx + *cx1], 400, g);
+    if (ret < 0)
+        return ret;
+
+    *cx1 = (*cx << 6) & 0xFC0;
+    *cx = *g >> cxshift;
+    ret = decode_unit(s, &s->pixel_model[2][*cx + *cx1], 400, b);
+    if (ret < 0)
+        return ret;
+
+    *cx1 = (*cx << 6) & 0xFC0;
+    *cx = *b >> cxshift;
+
+    return 0;
+}
+
 static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
 {
     SCPRContext *s = avctx->priv_data;
     GetByteContext *gb = &s->gb;
     int cx = 0, cx1 = 0, k = 0, clr = 0;
-    int run, r, g, b, off, y = 0, x = 0, z, ret;
-    unsigned backstep = linesize - avctx->width;
-    const int cxshift = s->cxshift;
+    int run, off, y = 0, x = 0, z, ret;
+    unsigned r, g, b, backstep = linesize - avctx->width;
     unsigned lx, ly, ptype;
 
     reinit_tables(s);
@@ -308,28 +339,15 @@ static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
     init_rangecoder(&s->rc, gb);
 
     while (k < avctx->width + 1) {
-        ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
-        if (ret < 0)
-            return ret;
-
-        cx1 = (cx << 6) & 0xFC0;
-        cx = r >> cxshift;
-        ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
+        ret = decode_units(s, &r, &g, &b, &cx, &cx1);
         if (ret < 0)
             return ret;
 
-        cx1 = (cx << 6) & 0xFC0;
-        cx = g >> cxshift;
-        ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
-        if (ret < 0)
-            return ret;
-
-        cx1 = (cx << 6) & 0xFC0;
-        cx = b >> cxshift;
-
         ret = decode_value(s, s->run_model[0], 256, 400, &run);
         if (ret < 0)
             return ret;
+        if (run <= 0)
+            return AVERROR_INVALIDDATA;
 
         clr = (b << 16) + (g << 8) + r;
         k += run;
@@ -355,19 +373,7 @@ static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
         if (ret < 0)
             return ret;
         if (ptype == 0) {
-            ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
-            if (ret < 0)
-                return ret;
-
-            cx1 = (cx << 6) & 0xFC0;
-            cx = r >> cxshift;
-            ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
-            if (ret < 0)
-                return ret;
-
-            cx1 = (cx << 6) & 0xFC0;
-            cx = g >> cxshift;
-            ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
+            ret = decode_units(s, &r, &g, &b, &cx, &cx1);
             if (ret < 0)
                 return ret;
 
@@ -378,6 +384,8 @@ static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
         ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
         if (ret < 0)
             return ret;
+        if (run <= 0)
+            return AVERROR_INVALIDDATA;
 
         switch (ptype) {
         case 0:
@@ -442,13 +450,13 @@ static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
                 }
 
                 r = odst[(ly * linesize + lx) * 4] +
-                    odst[((y * linesize + x) + off - z) * 4 + 4] -
+                    odst[((y * linesize + x) + off) * 4 + 4] -
                     odst[((y * linesize + x) + off - z) * 4];
                 g = odst[(ly * linesize + lx) * 4 + 1] +
-                    odst[((y * linesize + x) + off - z) * 4 + 5] -
+                    odst[((y * linesize + x) + off) * 4 + 5] -
                     odst[((y * linesize + x) + off - z) * 4 + 1];
                 b = odst[(ly * linesize + lx) * 4 + 2] +
-                    odst[((y * linesize + x) + off - z) * 4 + 6] -
+                    odst[((y * linesize + x) + off) * 4 + 6] -
                     odst[((y * linesize + x) + off - z) * 4 + 2];
                 clr = ((b & 0xFF) << 16) + ((g & 0xFF) << 8) + (r & 0xFF);
                 dst[y * linesize + x] = clr;
@@ -506,10 +514,9 @@ static int decompress_p(AVCodecContext *avctx,
     GetByteContext *gb = &s->gb;
     int ret, temp, min, max, x, y, cx = 0, cx1 = 0;
     int backstep = linesize - avctx->width;
-    const int cxshift = s->cxshift;
 
     if (bytestream2_get_byte(gb) == 0)
-        return 0;
+        return 1;
     bytestream2_skip(gb, 1);
     init_rangecoder(&s->rc, gb);
 
@@ -522,6 +529,9 @@ static int decompress_p(AVCodecContext *avctx,
         return ret;
 
     max += temp << 8;
+    if (min > max || min >= s->nbcount)
+        return AVERROR_INVALIDDATA;
+
     memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
 
     while (min <= max) {
@@ -531,6 +541,8 @@ static int decompress_p(AVCodecContext *avctx,
         ret |= decode_value(s, s->count_model, 256, 20, &count);
         if (ret < 0)
             return ret;
+        if (count <= 0)
+            return AVERROR_INVALIDDATA;
 
         while (min < s->nbcount && count-- > 0) {
             s->blocks[min++] = fill;
@@ -577,27 +589,15 @@ static int decompress_p(AVCodecContext *avctx,
                     }
                 }
             } else {
-                int run, r, g, b, z, bx = x * 16 + sx1, by = y * 16 + sy1;
-                unsigned clr, ptype = 0;
+                int run, z, bx = x * 16 + sx1, by = y * 16 + sy1;
+                unsigned r, g, b, clr, ptype = 0;
 
                 for (; by < y * 16 + sy2 && by < avctx->height;) {
                     ret = decode_value(s, s->op_model[ptype], 6, 1000, &ptype);
                     if (ret < 0)
                         return ret;
                     if (ptype == 0) {
-                        ret = decode_unit(s, &s->pixel_model[0][cx + cx1], 400, &r);
-                        if (ret < 0)
-                            return ret;
-
-                        cx1 = (cx << 6) & 0xFC0;
-                        cx = r >> cxshift;
-                        ret = decode_unit(s, &s->pixel_model[1][cx + cx1], 400, &g);
-                        if (ret < 0)
-                            return ret;
-
-                        cx1 = (cx << 6) & 0xFC0;
-                        cx = g >> cxshift;
-                        ret = decode_unit(s, &s->pixel_model[2][cx + cx1], 400, &b);
+                        ret = decode_units(s, &r, &g, &b, &cx, &cx1);
                         if (ret < 0)
                             return ret;
 
@@ -608,6 +608,8 @@ static int decompress_p(AVCodecContext *avctx,
                     ret = decode_value(s, s->run_model[ptype], 256, 400, &run);
                     if (ret < 0)
                         return ret;
+                    if (run <= 0)
+                        return AVERROR_INVALIDDATA;
 
                     switch (ptype) {
                     case 0:
@@ -811,6 +813,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
                            s->current_frame->linesize[0] / 4,
                            (uint32_t *)s->last_frame->data[0],
                            s->last_frame->linesize[0] / 4);
+        if (ret == 1)
+            return avpkt->size;
     } else {
         return AVERROR_PATCHWELCOME;
     }