Update libwebp to 0.4.0

third_party/libwebp/webp/demux.h

 // Copyright 2012 Google Inc. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the COPYING file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS. All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 // Demux API.
 // Enables extraction of image and extended format data from WebP files.
 
 // Code Example: Demuxing WebP data to extract all the frames, ICC profile
 // and EXIF/XMP metadata.
-//
-//   WebPDemuxer* demux = WebPDemux(&webp_data);
-//
-//   uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
-//   uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
-//   // ... (Get information about the features present in the WebP file).
-//   uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
-//
-//   // ... (Iterate over all frames).
-//   WebPIterator iter;
-//   if (WebPDemuxGetFrame(demux, 1, &iter)) {
-//     do {
-//       // ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
-//       // ... and get other frame properties like width, height, offsets etc.
-//       // ... see 'struct WebPIterator' below for more info).
-//     } while (WebPDemuxNextFrame(&iter));
-//     WebPDemuxReleaseIterator(&iter);
-//   }
-//
-//   // ... (Extract metadata).
-//   WebPChunkIterator chunk_iter;
-//   if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
-//   // ... (Consume the ICC profile in 'chunk_iter.chunk').
-//   WebPDemuxReleaseChunkIterator(&chunk_iter);
-//   if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
-//   // ... (Consume the EXIF metadata in 'chunk_iter.chunk').
-//   WebPDemuxReleaseChunkIterator(&chunk_iter);
-//   if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
-//   // ... (Consume the XMP metadata in 'chunk_iter.chunk').
-//   WebPDemuxReleaseChunkIterator(&chunk_iter);
-//   WebPDemuxDelete(demux);
+/*
+  WebPDemuxer* demux = WebPDemux(&webp_data);
+
+  uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
+  uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
+  // ... (Get information about the features present in the WebP file).
+  uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
+
+  // ... (Iterate over all frames).
+  WebPIterator iter;
+  if (WebPDemuxGetFrame(demux, 1, &iter)) {
+    do {
+      // ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
+      // ... and get other frame properties like width, height, offsets etc.
+      // ... see 'struct WebPIterator' below for more info).
+    } while (WebPDemuxNextFrame(&iter));
+    WebPDemuxReleaseIterator(&iter);
+  }
+
+  // ... (Extract metadata).
+  WebPChunkIterator chunk_iter;
+  if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
+  // ... (Consume the ICC profile in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
+  // ... (Consume the EXIF metadata in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
+  // ... (Consume the XMP metadata in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  WebPDemuxDelete(demux);
+*/
 
 #ifndef WEBP_WEBP_DEMUX_H_
 #define WEBP_WEBP_DEMUX_H_
 
 #include "./mux_types.h"
 
-#if defined(__cplusplus) || defined(c_plusplus)
+#ifdef __cplusplus
 extern "C" {
 #endif
 
 #define WEBP_DEMUX_ABI_VERSION 0x0101    // MAJOR(8b) + MINOR(8b)
 
 // Note: forward declaring enumerations is not allowed in (strict) C and C++,
 // the types are left here for reference.
 // typedef enum WebPDemuxState WebPDemuxState;
 // typedef enum WebPFormatFeature WebPFormatFeature;
 typedef struct WebPDemuxer WebPDemuxer;
 typedef struct WebPIterator WebPIterator;
 typedef struct WebPChunkIterator WebPChunkIterator;
 
 //------------------------------------------------------------------------------
 
 // Returns the version number of the demux library, packed in hexadecimal using
 // 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
 WEBP_EXTERN(int) WebPGetDemuxVersion(void);
 
 //------------------------------------------------------------------------------
 // Life of a Demux object
 
 typedef enum WebPDemuxState {
-  WEBP_DEMUX_PARSING_HEADER,  // Not enough data to parse full header.
-  WEBP_DEMUX_PARSED_HEADER,   // Header parsing complete, data may be available.
-  WEBP_DEMUX_DONE             // Entire file has been parsed.
+  WEBP_DEMUX_PARSE_ERROR    = -1,  // An error occurred while parsing.
+  WEBP_DEMUX_PARSING_HEADER =  0,  // Not enough data to parse full header.
+  WEBP_DEMUX_PARSED_HEADER  =  1,  // Header parsing complete,
+                                   // data may be available.
+  WEBP_DEMUX_DONE           =  2   // Entire file has been parsed.
 } WebPDemuxState;
 
 // Internal, version-checked, entry point
 WEBP_EXTERN(WebPDemuxer*) WebPDemuxInternal(
     const WebPData*, int, WebPDemuxState*, int);
 
 // Parses the full WebP file given by 'data'.
 // Returns a WebPDemuxer object on successful parse, NULL otherwise.
 static WEBP_INLINE WebPDemuxer* WebPDemux(const WebPData* data) {
   return WebPDemuxInternal(data, 0, NULL, WEBP_DEMUX_ABI_VERSION);
 }
 
 // Parses the possibly incomplete WebP file given by 'data'.
 // If 'state' is non-NULL it will be set to indicate the status of the demuxer.
-// Returns a WebPDemuxer object on successful parse, NULL otherwise.
+// Returns NULL in case of error or if there isn't enough data to start parsing;
+// and a WebPDemuxer object on successful parse.
+// Note that WebPDemuxer keeps internal pointers to 'data' memory segment.
+// If this data is volatile, the demuxer object should be deleted (by calling
+// WebPDemuxDelete()) and WebPDemuxPartial() called again on the new data.
+// This is usually an inexpensive operation.
 static WEBP_INLINE WebPDemuxer* WebPDemuxPartial(
     const WebPData* data, WebPDemuxState* state) {
   return WebPDemuxInternal(data, 1, state, WEBP_DEMUX_ABI_VERSION);
 }
 
 // Frees memory associated with 'dmux'.
 WEBP_EXTERN(void) WebPDemuxDelete(WebPDemuxer* dmux);
 
 //------------------------------------------------------------------------------
 // Data/information extraction.
@@ skipping 34 matching lines @@
                       // 'fragment_num'.
   int has_alpha;      // True if the frame or fragment contains transparency.
   WebPMuxAnimBlend blend_method;  // Blend operation for the frame.
 
   uint32_t pad[2];         // padding for later use.
   void* private_;          // for internal use only.
 };
 
 // Retrieves frame 'frame_number' from 'dmux'.
 // 'iter->fragment' points to the first fragment on return from this function.
-// Individual fragments may be extracted using WebPDemuxSetFragment().
+// Individual fragments may be extracted using WebPDemuxSelectFragment().
 // Setting 'frame_number' equal to 0 will return the last frame of the image.
 // Returns false if 'dmux' is NULL or frame 'frame_number' is not present.
 // Call WebPDemuxReleaseIterator() when use of the iterator is complete.
 // NOTE: 'dmux' must persist for the lifetime of 'iter'.
 WEBP_EXTERN(int) WebPDemuxGetFrame(
     const WebPDemuxer* dmux, int frame_number, WebPIterator* iter);
 
 // Sets 'iter->fragment' to point to the next ('iter->frame_num' + 1) or
 // previous ('iter->frame_num' - 1) frame. These functions do not loop.
 // Returns true on success, false otherwise.
@@ skipping 43 matching lines @@
 WEBP_EXTERN(int) WebPDemuxNextChunk(WebPChunkIterator* iter);
 WEBP_EXTERN(int) WebPDemuxPrevChunk(WebPChunkIterator* iter);
 
 // Releases any memory associated with 'iter'.
 // Must be called before destroying the associated WebPDemuxer with
 // WebPDemuxDelete().
 WEBP_EXTERN(void) WebPDemuxReleaseChunkIterator(WebPChunkIterator* iter);
 
 //------------------------------------------------------------------------------
 
-#if defined(__cplusplus) || defined(c_plusplus)
+#ifdef __cplusplus
 }    // extern "C"
 #endif
 
 #endif  /* WEBP_WEBP_DEMUX_H_ */