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-rw-r--r--base/pickle.cc449
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diff --git a/base/pickle.cc b/base/pickle.cc
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+// Copyright (c) 2011 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_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_(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::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::ReadUInt16(void** iter, uint16* 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::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::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);
+}
+
+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::ReadLength(void** iter, int* result) const {
+ if (!ReadInt(iter, result))
+ return false;
+ return ((*result) >= 0);
+}
+
+
+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 data_len) {
+ DCHECK_NE(kCapacityReadOnly, capacity_) << "oops: pickle is readonly";
+
+ char* dest = BeginWrite(data_len);
+ if (!dest)
+ return false;
+
+ memcpy(dest, data, data_len);
+
+ EndWrite(dest, data_len);
+ return true;
+}
+
+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;
+}
+
+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::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_EQ(header_size, AlignInt(header_size, sizeof(uint32)));
+ DCHECK_LE(header_size, static_cast<size_t>(kPayloadUnit));
+
+ if (static_cast<size_t>(end - start) < sizeof(Header))
+ return NULL;
+
+ 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;
+}