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Diffstat (limited to 'modules/woff2/src/buffer.h')
-rw-r--r-- | modules/woff2/src/buffer.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/modules/woff2/src/buffer.h b/modules/woff2/src/buffer.h new file mode 100644 index 000000000..588ac0d33 --- /dev/null +++ b/modules/woff2/src/buffer.h @@ -0,0 +1,172 @@ +// 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_ |