| // Copyright (c) 2006-2008 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() |
| #include <limits> |
| |
| //------------------------------------------------------------------------------ |
| |
| // static |
| const int Pickle::kPayloadUnit = 64; |
| |
| // We mark a read only pickle with a special capacity_. |
| static const size_t kCapacityReadOnly = std::numeric_limits<size_t>::max(); |
| |
| // Payload is uint32 aligned. |
| |
| Pickle::Pickle() |
| : header_(NULL), |
| header_size_(sizeof(Header)), |
| capacity_(0), |
| variable_buffer_offset_(0) { |
| Resize(kPayloadUnit); |
| header_->payload_size = 0; |
| } |
| |
| Pickle::Pickle(int header_size) |
| : header_(NULL), |
| header_size_(AlignInt(header_size, sizeof(uint32))), |
| capacity_(0), |
| variable_buffer_offset_(0) { |
| DCHECK(static_cast<size_t>(header_size) >= sizeof(Header)); |
| DCHECK(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_(kCapacityReadOnly), |
| variable_buffer_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_(0), |
| variable_buffer_offset_(other.variable_buffer_offset_) { |
| size_t payload_size = header_size_ + other.header_->payload_size; |
| bool resized = Resize(payload_size); |
| CHECK(resized); // Realloc failed. |
| memcpy(header_, other.header_, payload_size); |
| } |
| |
| Pickle::~Pickle() { |
| if (capacity_ != kCapacityReadOnly) |
| free(header_); |
| } |
| |
| Pickle& Pickle::operator=(const Pickle& other) { |
| if (this == &other) { |
| NOTREACHED(); |
| return *this; |
| } |
| if (capacity_ == kCapacityReadOnly) { |
| header_ = NULL; |
| capacity_ = 0; |
| } |
| if (header_size_ != other.header_size_) { |
| free(header_); |
| header_ = NULL; |
| header_size_ = other.header_size_; |
| } |
| bool resized = Resize(other.header_size_ + other.header_->payload_size); |
| CHECK(resized); // Realloc failed. |
| memcpy(header_, other.header_, |
| other.header_size_ + other.header_->payload_size); |
| variable_buffer_offset_ = other.variable_buffer_offset_; |
| return *this; |
| } |
| |
| bool Pickle::ReadBool(void** iter, bool* result) const { |
| DCHECK(iter); |
| |
| int tmp; |
| if (!ReadInt(iter, &tmp)) |
| return false; |
| DCHECK(0 == tmp || 1 == tmp); |
| *result = tmp ? true : false; |
| return true; |
| } |
| |
| bool Pickle::ReadInt(void** iter, int* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| // TODO(jar): http://crbug.com/13108 Pickle should be cleaned up, and not |
| // dependent on alignment. |
| // Next line is otherwise the same as: memcpy(result, *iter, sizeof(*result)); |
| *result = *reinterpret_cast<int*>(*iter); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadLong(void** iter, long* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| // TODO(jar): http://crbug.com/13108 Pickle should be cleaned up, and not |
| // dependent on alignment. |
| memcpy(result, *iter, sizeof(*result)); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadLength(void** iter, int* result) const { |
| if (!ReadInt(iter, result)) |
| return false; |
| return ((*result) >= 0); |
| } |
| |
| bool Pickle::ReadSize(void** iter, size_t* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| // TODO(jar): http://crbug.com/13108 Pickle should be cleaned up, and not |
| // dependent on alignment. |
| // Next line is otherwise the same as: memcpy(result, *iter, sizeof(*result)); |
| *result = *reinterpret_cast<size_t*>(*iter); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadUInt32(void** iter, uint32* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| memcpy(result, *iter, sizeof(*result)); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadInt64(void** iter, int64* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| memcpy(result, *iter, sizeof(*result)); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadUInt64(void** iter, uint64* result) const { |
| DCHECK(iter); |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, sizeof(*result))) |
| return false; |
| |
| memcpy(result, *iter, sizeof(*result)); |
| |
| UpdateIter(iter, sizeof(*result)); |
| return true; |
| } |
| |
| bool Pickle::ReadString(void** iter, std::string* result) const { |
| DCHECK(iter); |
| |
| int len; |
| if (!ReadLength(iter, &len)) |
| return false; |
| if (!IteratorHasRoomFor(*iter, len)) |
| return false; |
| |
| char* chars = reinterpret_cast<char*>(*iter); |
| result->assign(chars, len); |
| |
| UpdateIter(iter, len); |
| return true; |
| } |
| |
| bool Pickle::ReadWString(void** iter, std::wstring* result) const { |
| DCHECK(iter); |
| |
| int len; |
| if (!ReadLength(iter, &len)) |
| return false; |
| // Avoid integer overflow. |
| if (len > INT_MAX / static_cast<int>(sizeof(wchar_t))) |
| return false; |
| if (!IteratorHasRoomFor(*iter, len * sizeof(wchar_t))) |
| return false; |
| |
| wchar_t* chars = reinterpret_cast<wchar_t*>(*iter); |
| result->assign(chars, len); |
| |
| UpdateIter(iter, len * sizeof(wchar_t)); |
| return true; |
| } |
| |
| bool Pickle::ReadString16(void** iter, string16* result) const { |
| DCHECK(iter); |
| |
| int len; |
| if (!ReadLength(iter, &len)) |
| return false; |
| if (!IteratorHasRoomFor(*iter, len * sizeof(char16))) |
| return false; |
| |
| char16* chars = reinterpret_cast<char16*>(*iter); |
| result->assign(chars, len); |
| |
| UpdateIter(iter, len * sizeof(char16)); |
| return true; |
| } |
| |
| bool Pickle::ReadBytes(void** iter, const char** data, int length) const { |
| DCHECK(iter); |
| DCHECK(data); |
| *data = 0; |
| if (!*iter) |
| *iter = const_cast<char*>(payload()); |
| |
| if (!IteratorHasRoomFor(*iter, length)) |
| return false; |
| |
| *data = reinterpret_cast<const char*>(*iter); |
| |
| UpdateIter(iter, length); |
| return true; |
| } |
| |
| bool Pickle::ReadData(void** iter, const char** data, int* length) const { |
| DCHECK(iter); |
| DCHECK(data); |
| DCHECK(length); |
| *length = 0; |
| *data = 0; |
| |
| if (!ReadLength(iter, length)) |
| return false; |
| |
| return ReadBytes(iter, data, *length); |
| } |
| |
| char* Pickle::BeginWrite(size_t length) { |
| // write at a uint32-aligned offset from the beginning of the header |
| size_t offset = AlignInt(header_->payload_size, sizeof(uint32)); |
| |
| size_t new_size = offset + length; |
| size_t needed_size = header_size_ + new_size; |
| if (needed_size > capacity_ && !Resize(std::max(capacity_ * 2, needed_size))) |
| return NULL; |
| |
| #ifdef ARCH_CPU_64_BITS |
| DCHECK_LE(length, std::numeric_limits<uint32>::max()); |
| #endif |
| |
| header_->payload_size = static_cast<uint32>(new_size); |
| return payload() + offset; |
| } |
| |
| void Pickle::EndWrite(char* dest, int length) { |
| // Zero-pad to keep tools like purify from complaining about uninitialized |
| // memory. |
| if (length % sizeof(uint32)) |
| memset(dest + length, 0, sizeof(uint32) - (length % sizeof(uint32))); |
| } |
| |
| bool Pickle::WriteBytes(const void* data, int data_len) { |
| DCHECK(capacity_ != kCapacityReadOnly) << "oops: pickle is readonly"; |
| |
| char* dest = BeginWrite(data_len); |
| if (!dest) |
| return false; |
| |
| memcpy(dest, data, data_len); |
| |
| EndWrite(dest, data_len); |
| return true; |
| } |
| |
| 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); |
| } |
| |
| char* Pickle::BeginWriteData(int length) { |
| DCHECK_EQ(variable_buffer_offset_, 0U) << |
| "There can only be one variable buffer in a Pickle"; |
| |
| if (length < 0 || !WriteInt(length)) |
| return NULL; |
| |
| char *data_ptr = BeginWrite(length); |
| if (!data_ptr) |
| return NULL; |
| |
| variable_buffer_offset_ = |
| data_ptr - reinterpret_cast<char*>(header_) - sizeof(int); |
| |
| // EndWrite doesn't necessarily have to be called after the write operation, |
| // so we call it here to pad out what the caller will eventually write. |
| EndWrite(data_ptr, length); |
| return data_ptr; |
| } |
| |
| void Pickle::TrimWriteData(int new_length) { |
| DCHECK_NE(variable_buffer_offset_, 0U); |
| |
| // Fetch the the variable buffer size |
| int* cur_length = reinterpret_cast<int*>( |
| reinterpret_cast<char*>(header_) + variable_buffer_offset_); |
| |
| if (new_length < 0 || new_length > *cur_length) { |
| NOTREACHED() << "Invalid length in TrimWriteData."; |
| return; |
| } |
| |
| // Update the payload size and variable buffer size |
| header_->payload_size -= (*cur_length - new_length); |
| *cur_length = new_length; |
| } |
| |
| bool Pickle::Resize(size_t new_capacity) { |
| new_capacity = AlignInt(new_capacity, kPayloadUnit); |
| |
| CHECK_NE(capacity_, kCapacityReadOnly); |
| void* p = realloc(header_, new_capacity); |
| if (!p) |
| return false; |
| |
| header_ = reinterpret_cast<Header*>(p); |
| capacity_ = new_capacity; |
| return true; |
| } |
| |
| // static |
| const char* Pickle::FindNext(size_t header_size, |
| const char* start, |
| const char* end) { |
| DCHECK(header_size == AlignInt(header_size, sizeof(uint32))); |
| DCHECK(header_size <= static_cast<size_t>(kPayloadUnit)); |
| |
| const Header* hdr = reinterpret_cast<const Header*>(start); |
| const char* payload_base = start + header_size; |
| const char* payload_end = payload_base + hdr->payload_size; |
| if (payload_end < payload_base) |
| return NULL; |
| |
| return (payload_end > end) ? NULL : payload_end; |
| } |