libwebp-0.6.0-rc1

third_party/libwebp/utils/bit_reader.h

Index: third_party/libwebp/utils/bit_reader.h
diff --git a/third_party/libwebp/utils/bit_reader.h b/third_party/libwebp/utils/bit_reader.h
deleted file mode 100644
index ec3426cd11c892c1e4d7c3aaa503125902d2b4a0..0000000000000000000000000000000000000000
--- a/third_party/libwebp/utils/bit_reader.h
+++ /dev/null
@@ -1,174 +0,0 @@
-// Copyright 2010 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.
-// -----------------------------------------------------------------------------
-//
-// Boolean decoder
-//
-// Author: Skal (pascal.massimino@gmail.com)
-//         Vikas Arora (vikaas.arora@gmail.com)
-
-#ifndef WEBP_UTILS_BIT_READER_H_
-#define WEBP_UTILS_BIT_READER_H_
-
-#include <assert.h>
-#ifdef _MSC_VER
-#include <stdlib.h>  // _byteswap_ulong
-#endif
-#include "../webp/types.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-// The Boolean decoder needs to maintain infinite precision on the value_ field.
-// However, since range_ is only 8bit, we only need an active window of 8 bits
-// for value_. Left bits (MSB) gets zeroed and shifted away when value_ falls
-// below 128, range_ is updated, and fresh bits read from the bitstream are
-// brought in as LSB. To avoid reading the fresh bits one by one (slow), we
-// cache BITS of them ahead. The total of (BITS + 8) bits must fit into a
-// natural register (with type bit_t). To fetch BITS bits from bitstream we
-// use a type lbit_t.
-//
-// BITS can be any multiple of 8 from 8 to 56 (inclusive).
-// Pick values that fit natural register size.
-
-#if defined(__i386__) || defined(_M_IX86)      // x86 32bit
-#define BITS 24
-#elif defined(__x86_64__) || defined(_M_X64)   // x86 64bit
-#define BITS 56
-#elif defined(__arm__) || defined(_M_ARM)      // ARM
-#define BITS 24
-#elif defined(__aarch64__)                     // ARM 64bit
-#define BITS 56
-#elif defined(__mips__)                        // MIPS
-#define BITS 24
-#else                                          // reasonable default
-#define BITS 24
-#endif
-
-//------------------------------------------------------------------------------
-// Derived types and constants:
-//   bit_t = natural register type for storing 'value_' (which is BITS+8 bits)
-//   range_t = register for 'range_' (which is 8bits only)
-
-#if (BITS > 24)
-typedef uint64_t bit_t;
-#else
-typedef uint32_t bit_t;
-#endif
-
-typedef uint32_t range_t;
-
-//------------------------------------------------------------------------------
-// Bitreader
-
-typedef struct VP8BitReader VP8BitReader;
-struct VP8BitReader {
-  // boolean decoder  (keep the field ordering as is!)
-  bit_t value_;               // current value
-  range_t range_;             // current range minus 1. In [127, 254] interval.
-  int bits_;                  // number of valid bits left
-  // read buffer
-  const uint8_t* buf_;        // next byte to be read
-  const uint8_t* buf_end_;    // end of read buffer
-  const uint8_t* buf_max_;    // max packed-read position on buffer
-  int eof_;                   // true if input is exhausted
-};
-
-// Initialize the bit reader and the boolean decoder.
-void VP8InitBitReader(VP8BitReader* const br,
-                      const uint8_t* const start, size_t size);
-// Sets the working read buffer.
-void VP8BitReaderSetBuffer(VP8BitReader* const br,
-                           const uint8_t* const start, size_t size);
-
-// Update internal pointers to displace the byte buffer by the
-// relative offset 'offset'.
-void VP8RemapBitReader(VP8BitReader* const br, ptrdiff_t offset);
-
-// return the next value made of 'num_bits' bits
-uint32_t VP8GetValue(VP8BitReader* const br, int num_bits);
-static WEBP_INLINE uint32_t VP8Get(VP8BitReader* const br) {
-  return VP8GetValue(br, 1);
-}
-
-// return the next value with sign-extension.
-int32_t VP8GetSignedValue(VP8BitReader* const br, int num_bits);
-
-// bit_reader_inl.h will implement the following methods:
-//   static WEBP_INLINE int VP8GetBit(VP8BitReader* const br, int prob)
-//   static WEBP_INLINE int VP8GetSigned(VP8BitReader* const br, int v)
-// and should be included by the .c files that actually need them.
-// This is to avoid recompiling the whole library whenever this file is touched,
-// and also allowing platform-specific ad-hoc hacks.
-
-// -----------------------------------------------------------------------------
-// Bitreader for lossless format
-
-// maximum number of bits (inclusive) the bit-reader can handle:
-#define VP8L_MAX_NUM_BIT_READ 24
-
-#define VP8L_LBITS 64  // Number of bits prefetched (= bit-size of vp8l_val_t).
-#define VP8L_WBITS 32  // Minimum number of bytes ready after VP8LFillBitWindow.
-
-typedef uint64_t vp8l_val_t;  // right now, this bit-reader can only use 64bit.
-
-typedef struct {
-  vp8l_val_t     val_;        // pre-fetched bits
-  const uint8_t* buf_;        // input byte buffer
-  size_t         len_;        // buffer length
-  size_t         pos_;        // byte position in buf_
-  int            bit_pos_;    // current bit-reading position in val_
-  int            eos_;        // true if a bit was read past the end of buffer
-} VP8LBitReader;
-
-void VP8LInitBitReader(VP8LBitReader* const br,
-                       const uint8_t* const start,
-                       size_t length);
-
-//  Sets a new data buffer.
-void VP8LBitReaderSetBuffer(VP8LBitReader* const br,
-                            const uint8_t* const buffer, size_t length);
-
-// Reads the specified number of bits from read buffer.
-// Flags an error in case end_of_stream or n_bits is more than the allowed limit
-// of VP8L_MAX_NUM_BIT_READ (inclusive).
-// Flags eos_ if this read attempt is going to cross the read buffer.
-uint32_t VP8LReadBits(VP8LBitReader* const br, int n_bits);
-
-// Return the prefetched bits, so they can be looked up.
-static WEBP_INLINE uint32_t VP8LPrefetchBits(VP8LBitReader* const br) {
-  return (uint32_t)(br->val_ >> (br->bit_pos_ & (VP8L_LBITS - 1)));
-}
-
-// Returns true if there was an attempt at reading bit past the end of
-// the buffer. Doesn't set br->eos_ flag.
-static WEBP_INLINE int VP8LIsEndOfStream(const VP8LBitReader* const br) {
-  assert(br->pos_ <= br->len_);
-  return br->eos_ || ((br->pos_ == br->len_) && (br->bit_pos_ > VP8L_LBITS));
-}
-
-// For jumping over a number of bits in the bit stream when accessed with
-// VP8LPrefetchBits and VP8LFillBitWindow.
-static WEBP_INLINE void VP8LSetBitPos(VP8LBitReader* const br, int val) {
-  br->bit_pos_ = val;
-  br->eos_ = VP8LIsEndOfStream(br);
-}
-
-// Advances the read buffer by 4 bytes to make room for reading next 32 bits.
-// Speed critical, but infrequent part of the code can be non-inlined.
-extern void VP8LDoFillBitWindow(VP8LBitReader* const br);
-static WEBP_INLINE void VP8LFillBitWindow(VP8LBitReader* const br) {
-  if (br->bit_pos_ >= VP8L_WBITS) VP8LDoFillBitWindow(br);
-}
-
-#ifdef __cplusplus
-}    // extern "C"
-#endif
-
-#endif  /* WEBP_UTILS_BIT_READER_H_ */