blob: 4b6a1d8d629e9297e1d04dec66f7e965480b9652 [file] [log] [blame]
/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE 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.
*/
#include "webrtc/base/bytebuffer.h"
#include <assert.h>
#include <string.h>
#include <algorithm>
#include "webrtc/base/basictypes.h"
#include "webrtc/base/byteorder.h"
namespace rtc {
static const int DEFAULT_SIZE = 4096;
ByteBuffer::ByteBuffer() {
Construct(NULL, DEFAULT_SIZE, ORDER_NETWORK);
}
ByteBuffer::ByteBuffer(ByteOrder byte_order) {
Construct(NULL, DEFAULT_SIZE, byte_order);
}
ByteBuffer::ByteBuffer(const char* bytes, size_t len) {
Construct(bytes, len, ORDER_NETWORK);
}
ByteBuffer::ByteBuffer(const char* bytes, size_t len, ByteOrder byte_order) {
Construct(bytes, len, byte_order);
}
ByteBuffer::ByteBuffer(const char* bytes) {
Construct(bytes, strlen(bytes), ORDER_NETWORK);
}
ByteBuffer::ByteBuffer(const Buffer& buf) {
Construct(buf.data<char>(), buf.size(), ORDER_NETWORK);
}
void ByteBuffer::Construct(const char* bytes, size_t len,
ByteOrder byte_order) {
version_ = 0;
start_ = 0;
size_ = len;
byte_order_ = byte_order;
bytes_ = new char[size_];
if (bytes) {
end_ = len;
memcpy(bytes_, bytes, end_);
} else {
end_ = 0;
}
}
ByteBuffer::~ByteBuffer() {
delete[] bytes_;
}
bool ByteBuffer::ReadUInt8(uint8* val) {
if (!val) return false;
return ReadBytes(reinterpret_cast<char*>(val), 1);
}
bool ByteBuffer::ReadUInt16(uint16* val) {
if (!val) return false;
uint16 v;
if (!ReadBytes(reinterpret_cast<char*>(&v), 2)) {
return false;
} else {
*val = (byte_order_ == ORDER_NETWORK) ? NetworkToHost16(v) : v;
return true;
}
}
bool ByteBuffer::ReadUInt24(uint32* val) {
if (!val) return false;
uint32 v = 0;
char* read_into = reinterpret_cast<char*>(&v);
if (byte_order_ == ORDER_NETWORK || IsHostBigEndian()) {
++read_into;
}
if (!ReadBytes(read_into, 3)) {
return false;
} else {
*val = (byte_order_ == ORDER_NETWORK) ? NetworkToHost32(v) : v;
return true;
}
}
bool ByteBuffer::ReadUInt32(uint32* val) {
if (!val) return false;
uint32 v;
if (!ReadBytes(reinterpret_cast<char*>(&v), 4)) {
return false;
} else {
*val = (byte_order_ == ORDER_NETWORK) ? NetworkToHost32(v) : v;
return true;
}
}
bool ByteBuffer::ReadUInt64(uint64* val) {
if (!val) return false;
uint64 v;
if (!ReadBytes(reinterpret_cast<char*>(&v), 8)) {
return false;
} else {
*val = (byte_order_ == ORDER_NETWORK) ? NetworkToHost64(v) : v;
return true;
}
}
bool ByteBuffer::ReadString(std::string* val, size_t len) {
if (!val) return false;
if (len > Length()) {
return false;
} else {
val->append(bytes_ + start_, len);
start_ += len;
return true;
}
}
bool ByteBuffer::ReadBytes(char* val, size_t len) {
if (len > Length()) {
return false;
} else {
memcpy(val, bytes_ + start_, len);
start_ += len;
return true;
}
}
void ByteBuffer::WriteUInt8(uint8 val) {
WriteBytes(reinterpret_cast<const char*>(&val), 1);
}
void ByteBuffer::WriteUInt16(uint16 val) {
uint16 v = (byte_order_ == ORDER_NETWORK) ? HostToNetwork16(val) : val;
WriteBytes(reinterpret_cast<const char*>(&v), 2);
}
void ByteBuffer::WriteUInt24(uint32 val) {
uint32 v = (byte_order_ == ORDER_NETWORK) ? HostToNetwork32(val) : val;
char* start = reinterpret_cast<char*>(&v);
if (byte_order_ == ORDER_NETWORK || IsHostBigEndian()) {
++start;
}
WriteBytes(start, 3);
}
void ByteBuffer::WriteUInt32(uint32 val) {
uint32 v = (byte_order_ == ORDER_NETWORK) ? HostToNetwork32(val) : val;
WriteBytes(reinterpret_cast<const char*>(&v), 4);
}
void ByteBuffer::WriteUInt64(uint64 val) {
uint64 v = (byte_order_ == ORDER_NETWORK) ? HostToNetwork64(val) : val;
WriteBytes(reinterpret_cast<const char*>(&v), 8);
}
void ByteBuffer::WriteString(const std::string& val) {
WriteBytes(val.c_str(), val.size());
}
void ByteBuffer::WriteBytes(const char* val, size_t len) {
memcpy(ReserveWriteBuffer(len), val, len);
}
char* ByteBuffer::ReserveWriteBuffer(size_t len) {
if (Length() + len > Capacity())
Resize(Length() + len);
char* start = bytes_ + end_;
end_ += len;
return start;
}
void ByteBuffer::Resize(size_t size) {
size_t len = std::min(end_ - start_, size);
if (size <= size_) {
// Don't reallocate, just move data backwards
memmove(bytes_, bytes_ + start_, len);
} else {
// Reallocate a larger buffer.
size_ = std::max(size, 3 * size_ / 2);
char* new_bytes = new char[size_];
memcpy(new_bytes, bytes_ + start_, len);
delete [] bytes_;
bytes_ = new_bytes;
}
start_ = 0;
end_ = len;
++version_;
}
bool ByteBuffer::Consume(size_t size) {
if (size > Length())
return false;
start_ += size;
return true;
}
ByteBuffer::ReadPosition ByteBuffer::GetReadPosition() const {
return ReadPosition(start_, version_);
}
bool ByteBuffer::SetReadPosition(const ReadPosition &position) {
if (position.version_ != version_) {
return false;
}
start_ = position.start_;
return true;
}
void ByteBuffer::Clear() {
memset(bytes_, 0, size_);
start_ = end_ = 0;
++version_;
}
} // namespace rtc