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// Copyright 2013 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// The parts of ots.h & opentype-sanitiser.h that we need, taken from the
// https://code.google.com/p/ots/ project.
#ifndef WOFF2_BUFFER_H_
#define WOFF2_BUFFER_H_
#if defined(_WIN32)
#include <stdlib.h>
typedef signed char int8_t;
typedef unsigned char uint8_t;
typedef short int16_t;
typedef unsigned short uint16_t;
typedef int int32_t;
typedef unsigned int uint32_t;
typedef __int64 int64_t;
typedef unsigned __int64 uint64_t;
#define ntohl(x) _byteswap_ulong (x)
#define ntohs(x) _byteswap_ushort (x)
#define htonl(x) _byteswap_ulong (x)
#define htons(x) _byteswap_ushort (x)
#else
#include <arpa/inet.h>
#include <stdint.h>
#endif
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <limits>
namespace woff2 {
#if defined(_MSC_VER) || !defined(FONT_COMPRESSION_DEBUG)
#define FONT_COMPRESSION_FAILURE() false
#else
#define FONT_COMPRESSION_FAILURE() \
woff2::Failure(__FILE__, __LINE__, __PRETTY_FUNCTION__)
inline bool Failure(const char *f, int l, const char *fn) {
fprintf(stderr, "ERROR at %s:%d (%s)\n", f, l, fn);
fflush(stderr);
return false;
}
#endif
// -----------------------------------------------------------------------------
// Buffer helper class
//
// This class perform some trival buffer operations while checking for
// out-of-bounds errors. As a family they return false if anything is amiss,
// updating the current offset otherwise.
// -----------------------------------------------------------------------------
class Buffer {
public:
Buffer(const uint8_t *buffer, size_t len)
: buffer_(buffer),
length_(len),
offset_(0) { }
bool Skip(size_t n_bytes) {
return Read(NULL, n_bytes);
}
bool Read(uint8_t *buffer, size_t n_bytes) {
if (n_bytes > 1024 * 1024 * 1024) {
return FONT_COMPRESSION_FAILURE();
}
if ((offset_ + n_bytes > length_) ||
(offset_ > length_ - n_bytes)) {
return FONT_COMPRESSION_FAILURE();
}
if (buffer) {
std::memcpy(buffer, buffer_ + offset_, n_bytes);
}
offset_ += n_bytes;
return true;
}
inline bool ReadU8(uint8_t *value) {
if (offset_ + 1 > length_) {
return FONT_COMPRESSION_FAILURE();
}
*value = buffer_[offset_];
++offset_;
return true;
}
bool ReadU16(uint16_t *value) {
if (offset_ + 2 > length_) {
return FONT_COMPRESSION_FAILURE();
}
std::memcpy(value, buffer_ + offset_, sizeof(uint16_t));
*value = ntohs(*value);
offset_ += 2;
return true;
}
bool ReadS16(int16_t *value) {
return ReadU16(reinterpret_cast<uint16_t*>(value));
}
bool ReadU24(uint32_t *value) {
if (offset_ + 3 > length_) {
return FONT_COMPRESSION_FAILURE();
}
*value = static_cast<uint32_t>(buffer_[offset_]) << 16 |
static_cast<uint32_t>(buffer_[offset_ + 1]) << 8 |
static_cast<uint32_t>(buffer_[offset_ + 2]);
offset_ += 3;
return true;
}
bool ReadU32(uint32_t *value) {
if (offset_ + 4 > length_) {
return FONT_COMPRESSION_FAILURE();
}
std::memcpy(value, buffer_ + offset_, sizeof(uint32_t));
*value = ntohl(*value);
offset_ += 4;
return true;
}
bool ReadS32(int32_t *value) {
return ReadU32(reinterpret_cast<uint32_t*>(value));
}
bool ReadTag(uint32_t *value) {
if (offset_ + 4 > length_) {
return FONT_COMPRESSION_FAILURE();
}
std::memcpy(value, buffer_ + offset_, sizeof(uint32_t));
offset_ += 4;
return true;
}
bool ReadR64(uint64_t *value) {
if (offset_ + 8 > length_) {
return FONT_COMPRESSION_FAILURE();
}
std::memcpy(value, buffer_ + offset_, sizeof(uint64_t));
offset_ += 8;
return true;
}
const uint8_t *buffer() const { return buffer_; }
size_t offset() const { return offset_; }
size_t length() const { return length_; }
void set_offset(size_t newoffset) { offset_ = newoffset; }
private:
const uint8_t * const buffer_;
const size_t length_;
size_t offset_;
};
} // namespace woff2
#endif // WOFF2_BUFFER_H_