tiff: refactor fax support in a separate function

libavcodec/tiff.c

@@ -142,6 +142,38 @@ static int tiff_unpack_zlib(TiffContext *s, uint8_t *dst, int stride,
 }
 #endif
 
+
+static int tiff_unpack_fax(TiffContext *s, uint8_t *dst, int stride,
+                           const uint8_t *src, int size, int lines)
+{
+    int i, ret = 0;
+    uint8_t *src2 = av_malloc((unsigned)size +
+                              FF_INPUT_BUFFER_PADDING_SIZE);
+
+    if (!src2) {
+        av_log(s->avctx, AV_LOG_ERROR,
+               "Error allocating temporary buffer\n");
+        return AVERROR(ENOMEM);
+    }
+    if (s->fax_opts & 2) {
+        av_log(s->avctx, AV_LOG_ERROR,
+               "Uncompressed fax mode is not supported (yet)\n");
+        av_free(src2);
+        return AVERROR_INVALIDDATA;
+    }
+    if (!s->fill_order) {
+        memcpy(src2, src, size);
+    } else {
+        for (i = 0; i < size; i++)
+            src2[i] = ff_reverse[src[i]];
+    }
+    memset(src2 + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+    ret = ff_ccitt_unpack(s->avctx, src2, size, dst, lines, stride,
+                          s->compr, s->fax_opts);
+    av_free(src2);
+    return ret;
+}
+
 static int tiff_unpack_strip(TiffContext *s, uint8_t *dst, int stride,
                              const uint8_t *src, int size, int lines)
 {
@@ -171,38 +203,7 @@ static int tiff_unpack_strip(TiffContext *s, uint8_t *dst, int stride,
     if (s->compr == TIFF_CCITT_RLE ||
         s->compr == TIFF_G3        ||
         s->compr == TIFF_G4) {
-        int i, ret = 0;
-        uint8_t *src2 = av_malloc((unsigned)size +
-                                  FF_INPUT_BUFFER_PADDING_SIZE);
-
-        if (!src2) {
-            av_log(s->avctx, AV_LOG_ERROR,
-                   "Error allocating temporary buffer\n");
-            return AVERROR(ENOMEM);
-        }
-        if (s->fax_opts & 2) {
-            av_log(s->avctx, AV_LOG_ERROR,
-                   "Uncompressed fax mode is not supported (yet)\n");
-            av_free(src2);
-            return AVERROR_INVALIDDATA;
-        }
-        if (!s->fill_order) {
-            memcpy(src2, src, size);
-        } else {
-            for (i = 0; i < size; i++)
-                src2[i] = ff_reverse[src[i]];
-        }
-        memset(src2 + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
-        switch (s->compr) {
-        case TIFF_CCITT_RLE:
-        case TIFF_G3:
-        case TIFF_G4:
-            ret = ff_ccitt_unpack(s->avctx, src2, size, dst, lines, stride,
-                                  s->compr, s->fax_opts);
-            break;
-        }
-        av_free(src2);
-        return ret;
+        return tiff_unpack_fax(s, dst, stride, src, size, lines);
     }
     for (line = 0; line < lines; line++) {
         if (src - ssrc > size) {