libwebp: update to 0.5.0

This commit imports libwebp 0.5.0, including AUTHORS, COPYING, ChangeLog,
NEWS, PATENTS, README and src directories. In src, only includes header
and source files.

The patches required to build it in Qt will follow in separate
commit(s).

Change-Id: I96b4961ba63c75cc7fbab158c36a0f403f254c14
Reviewed-by: aavit <eirik.aavitsland@theqtcompany.com>

1 files changed, 20 insertions, 27 deletions

diff --git a/src/3rdparty/libwebp/src/dec/vp8.c b/src/3rdparty/libwebp/src/dec/vp8.c
index 89d478a..d89eb1c 100644
--- a/src/3rdparty/libwebp/src/dec/vp8.c
+++ b/src/3rdparty/libwebp/src/dec/vp8.c
@@ -75,10 +75,7 @@ void VP8Delete(VP8Decoder* const dec) {
 
 int VP8SetError(VP8Decoder* const dec,
                 VP8StatusCode error, const char* const msg) {
-  // TODO This check would be unnecessary if alpha decompression was separated
-  // from VP8ProcessRow/FinishRow. This avoids setting 'dec->status_' to
-  // something other than VP8_STATUS_BITSTREAM_ERROR on alpha decompression
-  // failure.
+  // The oldest error reported takes precedence over the new one.
   if (dec->status_ == VP8_STATUS_OK) {
     dec->status_ = error;
     dec->error_msg_ = msg;
@@ -193,25 +190,27 @@ static VP8StatusCode ParsePartitions(VP8Decoder* const dec,
   const uint8_t* sz = buf;
   const uint8_t* buf_end = buf + size;
   const uint8_t* part_start;
-  int last_part;
-  int p;
+  size_t size_left = size;
+  size_t last_part;
+  size_t p;
 
   dec->num_parts_ = 1 << VP8GetValue(br, 2);
   last_part = dec->num_parts_ - 1;
-  part_start = buf + last_part * 3;
-  if (buf_end < part_start) {
+  if (size < 3 * last_part) {
     // we can't even read the sizes with sz[]! That's a failure.
     return VP8_STATUS_NOT_ENOUGH_DATA;
   }
+  part_start = buf + last_part * 3;
+  size_left -= last_part * 3;
   for (p = 0; p < last_part; ++p) {
-    const uint32_t psize = sz[0] | (sz[1] << 8) | (sz[2] << 16);
-    const uint8_t* part_end = part_start + psize;
-    if (part_end > buf_end) part_end = buf_end;
-    VP8InitBitReader(dec->parts_ + p, part_start, part_end);
-    part_start = part_end;
+    size_t psize = sz[0] | (sz[1] << 8) | (sz[2] << 16);
+    if (psize > size_left) psize = size_left;
+    VP8InitBitReader(dec->parts_ + p, part_start, psize);
+    part_start += psize;
+    size_left -= psize;
     sz += 3;
   }
-  VP8InitBitReader(dec->parts_ + last_part, part_start, buf_end);
+  VP8InitBitReader(dec->parts_ + last_part, part_start, size_left);
   return (part_start < buf_end) ? VP8_STATUS_OK :
            VP8_STATUS_SUSPENDED;   // Init is ok, but there's not enough data
 }
@@ -328,7 +327,7 @@ int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
   }
 
   br = &dec->br_;
-  VP8InitBitReader(br, buf, buf + frm_hdr->partition_length_);
+  VP8InitBitReader(br, buf, frm_hdr->partition_length_);
   buf += frm_hdr->partition_length_;
   buf_size -= frm_hdr->partition_length_;
 
@@ -371,11 +370,6 @@ int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
 //------------------------------------------------------------------------------
 // Residual decoding (Paragraph 13.2 / 13.3)
 
-static const int kBands[16 + 1] = {
-  0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7,
-  0  // extra entry as sentinel
-};
-
 static const uint8_t kCat3[] = { 173, 148, 140, 0 };
 static const uint8_t kCat4[] = { 176, 155, 140, 135, 0 };
 static const uint8_t kCat5[] = { 180, 157, 141, 134, 130, 0 };
@@ -419,20 +413,19 @@ static int GetLargeValue(VP8BitReader* const br, const uint8_t* const p) {
 }
 
 // Returns the position of the last non-zero coeff plus one
-static int GetCoeffs(VP8BitReader* const br, const VP8BandProbas* const prob,
+static int GetCoeffs(VP8BitReader* const br, const VP8BandProbas* const prob[],
                      int ctx, const quant_t dq, int n, int16_t* out) {
-  // n is either 0 or 1 here. kBands[n] is not necessary for extracting '*p'.
-  const uint8_t* p = prob[n].probas_[ctx];
+  const uint8_t* p = prob[n]->probas_[ctx];
   for (; n < 16; ++n) {
     if (!VP8GetBit(br, p[0])) {
       return n;  // previous coeff was last non-zero coeff
     }
     while (!VP8GetBit(br, p[1])) {       // sequence of zero coeffs
-      p = prob[kBands[++n]].probas_[0];
+      p = prob[++n]->probas_[0];
       if (n == 16) return 16;
     }
     {        // non zero coeff
-      const VP8ProbaArray* const p_ctx = &prob[kBands[n + 1]].probas_[0];
+      const VP8ProbaArray* const p_ctx = &prob[n + 1]->probas_[0];
       int v;
       if (!VP8GetBit(br, p[2])) {
         v = 1;
@@ -455,8 +448,8 @@ static WEBP_INLINE uint32_t NzCodeBits(uint32_t nz_coeffs, int nz, int dc_nz) {
 
 static int ParseResiduals(VP8Decoder* const dec,
                           VP8MB* const mb, VP8BitReader* const token_br) {
-  VP8BandProbas (* const bands)[NUM_BANDS] = dec->proba_.bands_;
-  const VP8BandProbas* ac_proba;
+  const VP8BandProbas* (* const bands)[16 + 1] = dec->proba_.bands_ptr_;
+  const VP8BandProbas* const * ac_proba;
   VP8MBData* const block = dec->mb_data_ + dec->mb_x_;
   const VP8QuantMatrix* const q = &dec->dqm_[block->segment_];
   int16_t* dst = block->coeffs_;