| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "base/pickle.h" |
| |
| #include <stdlib.h> |
| |
| #include <algorithm> // for max() |
| |
| //------------------------------------------------------------------------------ |
| |
| using base::char16; |
| using base::string16; |
| |
| // static |
| const int Pickle::kPayloadUnit = 64; |
| |
| static const size_t kCapacityReadOnly = static_cast<size_t>(-1); |
| |
| PickleIterator::PickleIterator(const Pickle& pickle) |
| : payload_(pickle.payload()), |
| read_index_(0), |
| end_index_(pickle.payload_size()) { |
| } |
| |
| template <typename Type> |
| inline bool PickleIterator::ReadBuiltinType(Type* result) { |
| const char* read_from = GetReadPointerAndAdvance<Type>(); |
| if (!read_from) |
| return false; |
| if (sizeof(Type) > sizeof(uint32)) |
| memcpy(result, read_from, sizeof(*result)); |
| else |
| *result = *reinterpret_cast<const Type*>(read_from); |
| return true; |
| } |
| |
| inline void PickleIterator::Advance(size_t size) { |
| size_t aligned_size = AlignInt(size, sizeof(uint32_t)); |
| if (end_index_ - read_index_ < aligned_size) { |
| read_index_ = end_index_; |
| } else { |
| read_index_ += aligned_size; |
| } |
| } |
| |
| template<typename Type> |
| inline const char* PickleIterator::GetReadPointerAndAdvance() { |
| if (sizeof(Type) > end_index_ - read_index_) { |
| read_index_ = end_index_; |
| return NULL; |
| } |
| const char* current_read_ptr = payload_ + read_index_; |
| Advance(sizeof(Type)); |
| return current_read_ptr; |
| } |
| |
| const char* PickleIterator::GetReadPointerAndAdvance(int num_bytes) { |
| if (num_bytes < 0 || |
| end_index_ - read_index_ < static_cast<size_t>(num_bytes)) { |
| read_index_ = end_index_; |
| return NULL; |
| } |
| const char* current_read_ptr = payload_ + read_index_; |
| Advance(num_bytes); |
| return current_read_ptr; |
| } |
| |
| inline const char* PickleIterator::GetReadPointerAndAdvance( |
| int num_elements, |
| size_t size_element) { |
| // Check for int32 overflow. |
| int64 num_bytes = static_cast<int64>(num_elements) * size_element; |
| int num_bytes32 = static_cast<int>(num_bytes); |
| if (num_bytes != static_cast<int64>(num_bytes32)) |
| return NULL; |
| return GetReadPointerAndAdvance(num_bytes32); |
| } |
| |
| bool PickleIterator::ReadBool(bool* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadInt(int* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadLong(long* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadUInt16(uint16* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadUInt32(uint32* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadInt64(int64* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadUInt64(uint64* result) { |
| return ReadBuiltinType(result); |
| } |
| |
| bool PickleIterator::ReadSizeT(size_t* result) { |
| // Always read size_t as a 64-bit value to ensure compatibility between 32-bit |
| // and 64-bit processes. |
| uint64 result_uint64 = 0; |
| bool success = ReadBuiltinType(&result_uint64); |
| *result = static_cast<size_t>(result_uint64); |
| // Fail if the cast above truncates the value. |
| return success && (*result == result_uint64); |
| } |
| |
| bool PickleIterator::ReadFloat(float* result) { |
| // crbug.com/315213 |
| // The source data may not be properly aligned, and unaligned float reads |
| // cause SIGBUS on some ARM platforms, so force using memcpy to copy the data |
| // into the result. |
| const char* read_from = GetReadPointerAndAdvance<float>(); |
| if (!read_from) |
| return false; |
| memcpy(result, read_from, sizeof(*result)); |
| return true; |
| } |
| |
| bool PickleIterator::ReadDouble(double* result) { |
| // crbug.com/315213 |
| // The source data may not be properly aligned, and unaligned double reads |
| // cause SIGBUS on some ARM platforms, so force using memcpy to copy the data |
| // into the result. |
| const char* read_from = GetReadPointerAndAdvance<double>(); |
| if (!read_from) |
| return false; |
| memcpy(result, read_from, sizeof(*result)); |
| return true; |
| } |
| |
| bool PickleIterator::ReadString(std::string* result) { |
| int len; |
| if (!ReadInt(&len)) |
| return false; |
| const char* read_from = GetReadPointerAndAdvance(len); |
| if (!read_from) |
| return false; |
| |
| result->assign(read_from, len); |
| return true; |
| } |
| |
| bool PickleIterator::ReadWString(std::wstring* result) { |
| int len; |
| if (!ReadInt(&len)) |
| return false; |
| const char* read_from = GetReadPointerAndAdvance(len, sizeof(wchar_t)); |
| if (!read_from) |
| return false; |
| |
| result->assign(reinterpret_cast<const wchar_t*>(read_from), len); |
| return true; |
| } |
| |
| bool PickleIterator::ReadString16(string16* result) { |
| int len; |
| if (!ReadInt(&len)) |
| return false; |
| const char* read_from = GetReadPointerAndAdvance(len, sizeof(char16)); |
| if (!read_from) |
| return false; |
| |
| result->assign(reinterpret_cast<const char16*>(read_from), len); |
| return true; |
| } |
| |
| bool PickleIterator::ReadData(const char** data, int* length) { |
| *length = 0; |
| *data = 0; |
| |
| if (!ReadInt(length)) |
| return false; |
| |
| return ReadBytes(data, *length); |
| } |
| |
| bool PickleIterator::ReadBytes(const char** data, int length) { |
| const char* read_from = GetReadPointerAndAdvance(length); |
| if (!read_from) |
| return false; |
| *data = read_from; |
| return true; |
| } |
| |
| // Payload is uint32 aligned. |
| |
| Pickle::Pickle() |
| : header_(NULL), |
| header_size_(sizeof(Header)), |
| capacity_after_header_(0), |
| write_offset_(0) { |
| Resize(kPayloadUnit); |
| header_->payload_size = 0; |
| } |
| |
| Pickle::Pickle(int header_size) |
| : header_(NULL), |
| header_size_(AlignInt(header_size, sizeof(uint32))), |
| capacity_after_header_(0), |
| write_offset_(0) { |
| DCHECK_GE(static_cast<size_t>(header_size), sizeof(Header)); |
| DCHECK_LE(header_size, kPayloadUnit); |
| Resize(kPayloadUnit); |
| header_->payload_size = 0; |
| } |
| |
| Pickle::Pickle(const char* data, int data_len) |
| : header_(reinterpret_cast<Header*>(const_cast<char*>(data))), |
| header_size_(0), |
| capacity_after_header_(kCapacityReadOnly), |
| write_offset_(0) { |
| if (data_len >= static_cast<int>(sizeof(Header))) |
| header_size_ = data_len - header_->payload_size; |
| |
| if (header_size_ > static_cast<unsigned int>(data_len)) |
| header_size_ = 0; |
| |
| if (header_size_ != AlignInt(header_size_, sizeof(uint32))) |
| header_size_ = 0; |
| |
| // If there is anything wrong with the data, we're not going to use it. |
| if (!header_size_) |
| header_ = NULL; |
| } |
| |
| Pickle::Pickle(const Pickle& other) |
| : header_(NULL), |
| header_size_(other.header_size_), |
| capacity_after_header_(0), |
| write_offset_(other.write_offset_) { |
| size_t payload_size = header_size_ + other.header_->payload_size; |
| Resize(payload_size); |
| memcpy(header_, other.header_, payload_size); |
| } |
| |
| Pickle::~Pickle() { |
| if (capacity_after_header_ != kCapacityReadOnly) |
| free(header_); |
| } |
| |
| Pickle& Pickle::operator=(const Pickle& other) { |
| if (this == &other) { |
| NOTREACHED(); |
| return *this; |
| } |
| if (capacity_after_header_ == kCapacityReadOnly) { |
| header_ = NULL; |
| capacity_after_header_ = 0; |
| } |
| if (header_size_ != other.header_size_) { |
| free(header_); |
| header_ = NULL; |
| header_size_ = other.header_size_; |
| } |
| Resize(other.header_->payload_size); |
| memcpy(header_, other.header_, |
| other.header_size_ + other.header_->payload_size); |
| write_offset_ = other.write_offset_; |
| return *this; |
| } |
| |
| bool Pickle::WriteString(const std::string& value) { |
| if (!WriteInt(static_cast<int>(value.size()))) |
| return false; |
| |
| return WriteBytes(value.data(), static_cast<int>(value.size())); |
| } |
| |
| bool Pickle::WriteWString(const std::wstring& value) { |
| if (!WriteInt(static_cast<int>(value.size()))) |
| return false; |
| |
| return WriteBytes(value.data(), |
| static_cast<int>(value.size() * sizeof(wchar_t))); |
| } |
| |
| bool Pickle::WriteString16(const string16& value) { |
| if (!WriteInt(static_cast<int>(value.size()))) |
| return false; |
| |
| return WriteBytes(value.data(), |
| static_cast<int>(value.size()) * sizeof(char16)); |
| } |
| |
| bool Pickle::WriteData(const char* data, int length) { |
| return length >= 0 && WriteInt(length) && WriteBytes(data, length); |
| } |
| |
| bool Pickle::WriteBytes(const void* data, int length) { |
| WriteBytesCommon(data, length); |
| return true; |
| } |
| |
| void Pickle::Reserve(size_t length) { |
| size_t data_len = AlignInt(length, sizeof(uint32)); |
| DCHECK_GE(data_len, length); |
| #ifdef ARCH_CPU_64_BITS |
| DCHECK_LE(data_len, kuint32max); |
| #endif |
| DCHECK_LE(write_offset_, kuint32max - data_len); |
| size_t new_size = write_offset_ + data_len; |
| if (new_size > capacity_after_header_) |
| Resize(capacity_after_header_ * 2 + new_size); |
| } |
| |
| void Pickle::Resize(size_t new_capacity) { |
| new_capacity = AlignInt(new_capacity, kPayloadUnit); |
| |
| CHECK_NE(capacity_after_header_, kCapacityReadOnly); |
| void* p = realloc(header_, header_size_ + new_capacity); |
| CHECK(p); |
| header_ = reinterpret_cast<Header*>(p); |
| capacity_after_header_ = new_capacity; |
| } |
| |
| // static |
| const char* Pickle::FindNext(size_t header_size, |
| const char* start, |
| const char* end) { |
| DCHECK_EQ(header_size, AlignInt(header_size, sizeof(uint32))); |
| DCHECK_LE(header_size, static_cast<size_t>(kPayloadUnit)); |
| |
| size_t length = static_cast<size_t>(end - start); |
| if (length < sizeof(Header)) |
| return NULL; |
| |
| const Header* hdr = reinterpret_cast<const Header*>(start); |
| if (length < header_size || length - header_size < hdr->payload_size) |
| return NULL; |
| return start + header_size + hdr->payload_size; |
| } |
| |
| template <size_t length> void Pickle::WriteBytesStatic(const void* data) { |
| WriteBytesCommon(data, length); |
| } |
| |
| template void Pickle::WriteBytesStatic<2>(const void* data); |
| template void Pickle::WriteBytesStatic<4>(const void* data); |
| template void Pickle::WriteBytesStatic<8>(const void* data); |
| |
| inline void Pickle::WriteBytesCommon(const void* data, size_t length) { |
| DCHECK_NE(kCapacityReadOnly, capacity_after_header_) |
| << "oops: pickle is readonly"; |
| size_t data_len = AlignInt(length, sizeof(uint32)); |
| DCHECK_GE(data_len, length); |
| #ifdef ARCH_CPU_64_BITS |
| DCHECK_LE(data_len, kuint32max); |
| #endif |
| DCHECK_LE(write_offset_, kuint32max - data_len); |
| size_t new_size = write_offset_ + data_len; |
| if (new_size > capacity_after_header_) { |
| Resize(std::max(capacity_after_header_ * 2, new_size)); |
| } |
| |
| char* write = mutable_payload() + write_offset_; |
| memcpy(write, data, length); |
| memset(write + length, 0, data_len - length); |
| header_->payload_size = static_cast<uint32>(new_size); |
| write_offset_ = new_size; |
| } |