diff options
Diffstat (limited to 'toolkit/components/protobuf/src/google/protobuf/io/coded_stream.cc')
| -rw-r--r-- | toolkit/components/protobuf/src/google/protobuf/io/coded_stream.cc | 967 |
1 files changed, 967 insertions, 0 deletions
diff --git a/toolkit/components/protobuf/src/google/protobuf/io/coded_stream.cc b/toolkit/components/protobuf/src/google/protobuf/io/coded_stream.cc new file mode 100644 index 0000000000..487e1b8a37 --- /dev/null +++ b/toolkit/components/protobuf/src/google/protobuf/io/coded_stream.cc @@ -0,0 +1,967 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2008 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// Author: kenton@google.com (Kenton Varda) +// Based on original Protocol Buffers design by +// Sanjay Ghemawat, Jeff Dean, and others. +// +// This implementation is heavily optimized to make reads and writes +// of small values (especially varints) as fast as possible. In +// particular, we optimize for the common case that a read or a write +// will not cross the end of the buffer, since we can avoid a lot +// of branching in this case. + +#include <google/protobuf/io/coded_stream.h> + +#include <limits.h> + +#include <algorithm> +#include <cstring> +#include <utility> + +#include <google/protobuf/stubs/logging.h> +#include <google/protobuf/stubs/common.h> +#include <google/protobuf/arena.h> +#include <google/protobuf/io/zero_copy_stream.h> +#include <google/protobuf/io/zero_copy_stream_impl_lite.h> +#include <google/protobuf/stubs/stl_util.h> + + +// Must be included last. +#include <google/protobuf/port_def.inc> + +namespace google { +namespace protobuf { +namespace io { + +namespace { + +static const int kMaxVarintBytes = 10; +static const int kMaxVarint32Bytes = 5; + + +inline bool NextNonEmpty(ZeroCopyInputStream* input, const void** data, + int* size) { + bool success; + do { + success = input->Next(data, size); + } while (success && *size == 0); + return success; +} + +} // namespace + +// CodedInputStream ================================================== + +CodedInputStream::~CodedInputStream() { + if (input_ != NULL) { + BackUpInputToCurrentPosition(); + } +} + +// Static. +int CodedInputStream::default_recursion_limit_ = 100; + + +void CodedInputStream::BackUpInputToCurrentPosition() { + int backup_bytes = BufferSize() + buffer_size_after_limit_ + overflow_bytes_; + if (backup_bytes > 0) { + input_->BackUp(backup_bytes); + + // total_bytes_read_ doesn't include overflow_bytes_. + total_bytes_read_ -= BufferSize() + buffer_size_after_limit_; + buffer_end_ = buffer_; + buffer_size_after_limit_ = 0; + overflow_bytes_ = 0; + } +} + +inline void CodedInputStream::RecomputeBufferLimits() { + buffer_end_ += buffer_size_after_limit_; + int closest_limit = std::min(current_limit_, total_bytes_limit_); + if (closest_limit < total_bytes_read_) { + // The limit position is in the current buffer. We must adjust + // the buffer size accordingly. + buffer_size_after_limit_ = total_bytes_read_ - closest_limit; + buffer_end_ -= buffer_size_after_limit_; + } else { + buffer_size_after_limit_ = 0; + } +} + +CodedInputStream::Limit CodedInputStream::PushLimit(int byte_limit) { + // Current position relative to the beginning of the stream. + int current_position = CurrentPosition(); + + Limit old_limit = current_limit_; + + // security: byte_limit is possibly evil, so check for negative values + // and overflow. Also check that the new requested limit is before the + // previous limit; otherwise we continue to enforce the previous limit. + if (PROTOBUF_PREDICT_TRUE(byte_limit >= 0 && + byte_limit <= INT_MAX - current_position && + byte_limit < current_limit_ - current_position)) { + current_limit_ = current_position + byte_limit; + RecomputeBufferLimits(); + } + + return old_limit; +} + +void CodedInputStream::PopLimit(Limit limit) { + // The limit passed in is actually the *old* limit, which we returned from + // PushLimit(). + current_limit_ = limit; + RecomputeBufferLimits(); + + // We may no longer be at a legitimate message end. ReadTag() needs to be + // called again to find out. + legitimate_message_end_ = false; +} + +std::pair<CodedInputStream::Limit, int> +CodedInputStream::IncrementRecursionDepthAndPushLimit(int byte_limit) { + return std::make_pair(PushLimit(byte_limit), --recursion_budget_); +} + +CodedInputStream::Limit CodedInputStream::ReadLengthAndPushLimit() { + uint32_t length; + return PushLimit(ReadVarint32(&length) ? length : 0); +} + +bool CodedInputStream::DecrementRecursionDepthAndPopLimit(Limit limit) { + bool result = ConsumedEntireMessage(); + PopLimit(limit); + GOOGLE_DCHECK_LT(recursion_budget_, recursion_limit_); + ++recursion_budget_; + return result; +} + +bool CodedInputStream::CheckEntireMessageConsumedAndPopLimit(Limit limit) { + bool result = ConsumedEntireMessage(); + PopLimit(limit); + return result; +} + +int CodedInputStream::BytesUntilLimit() const { + if (current_limit_ == INT_MAX) return -1; + int current_position = CurrentPosition(); + + return current_limit_ - current_position; +} + +void CodedInputStream::SetTotalBytesLimit(int total_bytes_limit) { + // Make sure the limit isn't already past, since this could confuse other + // code. + int current_position = CurrentPosition(); + total_bytes_limit_ = std::max(current_position, total_bytes_limit); + RecomputeBufferLimits(); +} + +int CodedInputStream::BytesUntilTotalBytesLimit() const { + if (total_bytes_limit_ == INT_MAX) return -1; + return total_bytes_limit_ - CurrentPosition(); +} + +void CodedInputStream::PrintTotalBytesLimitError() { + GOOGLE_LOG(ERROR) + << "A protocol message was rejected because it was too " + "big (more than " + << total_bytes_limit_ + << " bytes). To increase the limit (or to disable these " + "warnings), see CodedInputStream::SetTotalBytesLimit() " + "in third_party/protobuf/io/coded_stream.h."; +} + +bool CodedInputStream::SkipFallback(int count, int original_buffer_size) { + if (buffer_size_after_limit_ > 0) { + // We hit a limit inside this buffer. Advance to the limit and fail. + Advance(original_buffer_size); + return false; + } + + count -= original_buffer_size; + buffer_ = NULL; + buffer_end_ = buffer_; + + // Make sure this skip doesn't try to skip past the current limit. + int closest_limit = std::min(current_limit_, total_bytes_limit_); + int bytes_until_limit = closest_limit - total_bytes_read_; + if (bytes_until_limit < count) { + // We hit the limit. Skip up to it then fail. + if (bytes_until_limit > 0) { + total_bytes_read_ = closest_limit; + input_->Skip(bytes_until_limit); + } + return false; + } + + if (!input_->Skip(count)) { + total_bytes_read_ = input_->ByteCount(); + return false; + } + total_bytes_read_ += count; + return true; +} + +bool CodedInputStream::GetDirectBufferPointer(const void** data, int* size) { + if (BufferSize() == 0 && !Refresh()) return false; + + *data = buffer_; + *size = BufferSize(); + return true; +} + +bool CodedInputStream::ReadRaw(void* buffer, int size) { + int current_buffer_size; + while ((current_buffer_size = BufferSize()) < size) { + // Reading past end of buffer. Copy what we have, then refresh. + memcpy(buffer, buffer_, current_buffer_size); + buffer = reinterpret_cast<uint8_t*>(buffer) + current_buffer_size; + size -= current_buffer_size; + Advance(current_buffer_size); + if (!Refresh()) return false; + } + + memcpy(buffer, buffer_, size); + Advance(size); + + return true; +} + +bool CodedInputStream::ReadString(std::string* buffer, int size) { + if (size < 0) return false; // security: size is often user-supplied + + if (BufferSize() >= size) { + STLStringResizeUninitialized(buffer, size); + std::pair<char*, bool> z = as_string_data(buffer); + if (z.second) { + // Oddly enough, memcpy() requires its first two args to be non-NULL even + // if we copy 0 bytes. So, we have ensured that z.first is non-NULL here. + GOOGLE_DCHECK(z.first != NULL); + memcpy(z.first, buffer_, size); + Advance(size); + } + return true; + } + + return ReadStringFallback(buffer, size); +} + +bool CodedInputStream::ReadStringFallback(std::string* buffer, int size) { + if (!buffer->empty()) { + buffer->clear(); + } + + int closest_limit = std::min(current_limit_, total_bytes_limit_); + if (closest_limit != INT_MAX) { + int bytes_to_limit = closest_limit - CurrentPosition(); + if (bytes_to_limit > 0 && size > 0 && size <= bytes_to_limit) { + buffer->reserve(size); + } + } + + int current_buffer_size; + while ((current_buffer_size = BufferSize()) < size) { + // Some STL implementations "helpfully" crash on buffer->append(NULL, 0). + if (current_buffer_size != 0) { + // Note: string1.append(string2) is O(string2.size()) (as opposed to + // O(string1.size() + string2.size()), which would be bad). + buffer->append(reinterpret_cast<const char*>(buffer_), + current_buffer_size); + } + size -= current_buffer_size; + Advance(current_buffer_size); + if (!Refresh()) return false; + } + + buffer->append(reinterpret_cast<const char*>(buffer_), size); + Advance(size); + + return true; +} + + +bool CodedInputStream::ReadLittleEndian32Fallback(uint32_t* value) { + uint8_t bytes[sizeof(*value)]; + + const uint8_t* ptr; + if (BufferSize() >= static_cast<int64_t>(sizeof(*value))) { + // Fast path: Enough bytes in the buffer to read directly. + ptr = buffer_; + Advance(sizeof(*value)); + } else { + // Slow path: Had to read past the end of the buffer. + if (!ReadRaw(bytes, sizeof(*value))) return false; + ptr = bytes; + } + ReadLittleEndian32FromArray(ptr, value); + return true; +} + +bool CodedInputStream::ReadLittleEndian64Fallback(uint64_t* value) { + uint8_t bytes[sizeof(*value)]; + + const uint8_t* ptr; + if (BufferSize() >= static_cast<int64_t>(sizeof(*value))) { + // Fast path: Enough bytes in the buffer to read directly. + ptr = buffer_; + Advance(sizeof(*value)); + } else { + // Slow path: Had to read past the end of the buffer. + if (!ReadRaw(bytes, sizeof(*value))) return false; + ptr = bytes; + } + ReadLittleEndian64FromArray(ptr, value); + return true; +} + +namespace { + +// Decodes varint64 with known size, N, and returns next pointer. Knowing N at +// compile time, compiler can generate optimal code. For example, instead of +// subtracting 0x80 at each iteration, it subtracts properly shifted mask once. +template <size_t N> +const uint8_t* DecodeVarint64KnownSize(const uint8_t* buffer, uint64_t* value) { + GOOGLE_DCHECK_GT(N, 0); + uint64_t result = static_cast<uint64_t>(buffer[N - 1]) << (7 * (N - 1)); + for (size_t i = 0, offset = 0; i < N - 1; i++, offset += 7) { + result += static_cast<uint64_t>(buffer[i] - 0x80) << offset; + } + *value = result; + return buffer + N; +} + +// Read a varint from the given buffer, write it to *value, and return a pair. +// The first part of the pair is true iff the read was successful. The second +// part is buffer + (number of bytes read). This function is always inlined, +// so returning a pair is costless. +PROTOBUF_ALWAYS_INLINE +::std::pair<bool, const uint8_t*> ReadVarint32FromArray(uint32_t first_byte, + const uint8_t* buffer, + uint32_t* value); +inline ::std::pair<bool, const uint8_t*> ReadVarint32FromArray( + uint32_t first_byte, const uint8_t* buffer, uint32_t* value) { + // Fast path: We have enough bytes left in the buffer to guarantee that + // this read won't cross the end, so we can skip the checks. + GOOGLE_DCHECK_EQ(*buffer, first_byte); + GOOGLE_DCHECK_EQ(first_byte & 0x80, 0x80) << first_byte; + const uint8_t* ptr = buffer; + uint32_t b; + uint32_t result = first_byte - 0x80; + ++ptr; // We just processed the first byte. Move on to the second. + b = *(ptr++); + result += b << 7; + if (!(b & 0x80)) goto done; + result -= 0x80 << 7; + b = *(ptr++); + result += b << 14; + if (!(b & 0x80)) goto done; + result -= 0x80 << 14; + b = *(ptr++); + result += b << 21; + if (!(b & 0x80)) goto done; + result -= 0x80 << 21; + b = *(ptr++); + result += b << 28; + if (!(b & 0x80)) goto done; + // "result -= 0x80 << 28" is irrelevant. + + // If the input is larger than 32 bits, we still need to read it all + // and discard the high-order bits. + for (int i = 0; i < kMaxVarintBytes - kMaxVarint32Bytes; i++) { + b = *(ptr++); + if (!(b & 0x80)) goto done; + } + + // We have overrun the maximum size of a varint (10 bytes). Assume + // the data is corrupt. + return std::make_pair(false, ptr); + +done: + *value = result; + return std::make_pair(true, ptr); +} + +PROTOBUF_ALWAYS_INLINE::std::pair<bool, const uint8_t*> ReadVarint64FromArray( + const uint8_t* buffer, uint64_t* value); +inline ::std::pair<bool, const uint8_t*> ReadVarint64FromArray( + const uint8_t* buffer, uint64_t* value) { + // Assumes varint64 is at least 2 bytes. + GOOGLE_DCHECK_GE(buffer[0], 128); + + const uint8_t* next; + if (buffer[1] < 128) { + next = DecodeVarint64KnownSize<2>(buffer, value); + } else if (buffer[2] < 128) { + next = DecodeVarint64KnownSize<3>(buffer, value); + } else if (buffer[3] < 128) { + next = DecodeVarint64KnownSize<4>(buffer, value); + } else if (buffer[4] < 128) { + next = DecodeVarint64KnownSize<5>(buffer, value); + } else if (buffer[5] < 128) { + next = DecodeVarint64KnownSize<6>(buffer, value); + } else if (buffer[6] < 128) { + next = DecodeVarint64KnownSize<7>(buffer, value); + } else if (buffer[7] < 128) { + next = DecodeVarint64KnownSize<8>(buffer, value); + } else if (buffer[8] < 128) { + next = DecodeVarint64KnownSize<9>(buffer, value); + } else if (buffer[9] < 128) { + next = DecodeVarint64KnownSize<10>(buffer, value); + } else { + // We have overrun the maximum size of a varint (10 bytes). Assume + // the data is corrupt. + return std::make_pair(false, buffer + 11); + } + + return std::make_pair(true, next); +} + +} // namespace + +bool CodedInputStream::ReadVarint32Slow(uint32_t* value) { + // Directly invoke ReadVarint64Fallback, since we already tried to optimize + // for one-byte varints. + std::pair<uint64_t, bool> p = ReadVarint64Fallback(); + *value = static_cast<uint32_t>(p.first); + return p.second; +} + +int64_t CodedInputStream::ReadVarint32Fallback(uint32_t first_byte_or_zero) { + if (BufferSize() >= kMaxVarintBytes || + // Optimization: We're also safe if the buffer is non-empty and it ends + // with a byte that would terminate a varint. + (buffer_end_ > buffer_ && !(buffer_end_[-1] & 0x80))) { + GOOGLE_DCHECK_NE(first_byte_or_zero, 0) + << "Caller should provide us with *buffer_ when buffer is non-empty"; + uint32_t temp; + ::std::pair<bool, const uint8_t*> p = + ReadVarint32FromArray(first_byte_or_zero, buffer_, &temp); + if (!p.first) return -1; + buffer_ = p.second; + return temp; + } else { + // Really slow case: we will incur the cost of an extra function call here, + // but moving this out of line reduces the size of this function, which + // improves the common case. In micro benchmarks, this is worth about 10-15% + uint32_t temp; + return ReadVarint32Slow(&temp) ? static_cast<int64_t>(temp) : -1; + } +} + +int CodedInputStream::ReadVarintSizeAsIntSlow() { + // Directly invoke ReadVarint64Fallback, since we already tried to optimize + // for one-byte varints. + std::pair<uint64_t, bool> p = ReadVarint64Fallback(); + if (!p.second || p.first > static_cast<uint64_t>(INT_MAX)) return -1; + return p.first; +} + +int CodedInputStream::ReadVarintSizeAsIntFallback() { + if (BufferSize() >= kMaxVarintBytes || + // Optimization: We're also safe if the buffer is non-empty and it ends + // with a byte that would terminate a varint. + (buffer_end_ > buffer_ && !(buffer_end_[-1] & 0x80))) { + uint64_t temp; + ::std::pair<bool, const uint8_t*> p = ReadVarint64FromArray(buffer_, &temp); + if (!p.first || temp > static_cast<uint64_t>(INT_MAX)) return -1; + buffer_ = p.second; + return temp; + } else { + // Really slow case: we will incur the cost of an extra function call here, + // but moving this out of line reduces the size of this function, which + // improves the common case. In micro benchmarks, this is worth about 10-15% + return ReadVarintSizeAsIntSlow(); + } +} + +uint32_t CodedInputStream::ReadTagSlow() { + if (buffer_ == buffer_end_) { + // Call refresh. + if (!Refresh()) { + // Refresh failed. Make sure that it failed due to EOF, not because + // we hit total_bytes_limit_, which, unlike normal limits, is not a + // valid place to end a message. + int current_position = total_bytes_read_ - buffer_size_after_limit_; + if (current_position >= total_bytes_limit_) { + // Hit total_bytes_limit_. But if we also hit the normal limit, + // we're still OK. + legitimate_message_end_ = current_limit_ == total_bytes_limit_; + } else { + legitimate_message_end_ = true; + } + return 0; + } + } + + // For the slow path, just do a 64-bit read. Try to optimize for one-byte tags + // again, since we have now refreshed the buffer. + uint64_t result = 0; + if (!ReadVarint64(&result)) return 0; + return static_cast<uint32_t>(result); +} + +uint32_t CodedInputStream::ReadTagFallback(uint32_t first_byte_or_zero) { + const int buf_size = BufferSize(); + if (buf_size >= kMaxVarintBytes || + // Optimization: We're also safe if the buffer is non-empty and it ends + // with a byte that would terminate a varint. + (buf_size > 0 && !(buffer_end_[-1] & 0x80))) { + GOOGLE_DCHECK_EQ(first_byte_or_zero, buffer_[0]); + if (first_byte_or_zero == 0) { + ++buffer_; + return 0; + } + uint32_t tag; + ::std::pair<bool, const uint8_t*> p = + ReadVarint32FromArray(first_byte_or_zero, buffer_, &tag); + if (!p.first) { + return 0; + } + buffer_ = p.second; + return tag; + } else { + // We are commonly at a limit when attempting to read tags. Try to quickly + // detect this case without making another function call. + if ((buf_size == 0) && + ((buffer_size_after_limit_ > 0) || + (total_bytes_read_ == current_limit_)) && + // Make sure that the limit we hit is not total_bytes_limit_, since + // in that case we still need to call Refresh() so that it prints an + // error. + total_bytes_read_ - buffer_size_after_limit_ < total_bytes_limit_) { + // We hit a byte limit. + legitimate_message_end_ = true; + return 0; + } + return ReadTagSlow(); + } +} + +bool CodedInputStream::ReadVarint64Slow(uint64_t* value) { + // Slow path: This read might cross the end of the buffer, so we + // need to check and refresh the buffer if and when it does. + + uint64_t result = 0; + int count = 0; + uint32_t b; + + do { + if (count == kMaxVarintBytes) { + *value = 0; + return false; + } + while (buffer_ == buffer_end_) { + if (!Refresh()) { + *value = 0; + return false; + } + } + b = *buffer_; + result |= static_cast<uint64_t>(b & 0x7F) << (7 * count); + Advance(1); + ++count; + } while (b & 0x80); + + *value = result; + return true; +} + +std::pair<uint64_t, bool> CodedInputStream::ReadVarint64Fallback() { + if (BufferSize() >= kMaxVarintBytes || + // Optimization: We're also safe if the buffer is non-empty and it ends + // with a byte that would terminate a varint. + (buffer_end_ > buffer_ && !(buffer_end_[-1] & 0x80))) { + uint64_t temp; + ::std::pair<bool, const uint8_t*> p = ReadVarint64FromArray(buffer_, &temp); + if (!p.first) { + return std::make_pair(0, false); + } + buffer_ = p.second; + return std::make_pair(temp, true); + } else { + uint64_t temp; + bool success = ReadVarint64Slow(&temp); + return std::make_pair(temp, success); + } +} + +bool CodedInputStream::Refresh() { + GOOGLE_DCHECK_EQ(0, BufferSize()); + + if (buffer_size_after_limit_ > 0 || overflow_bytes_ > 0 || + total_bytes_read_ == current_limit_) { + // We've hit a limit. Stop. + int current_position = total_bytes_read_ - buffer_size_after_limit_; + + if (current_position >= total_bytes_limit_ && + total_bytes_limit_ != current_limit_) { + // Hit total_bytes_limit_. + PrintTotalBytesLimitError(); + } + + return false; + } + + const void* void_buffer; + int buffer_size; + if (NextNonEmpty(input_, &void_buffer, &buffer_size)) { + buffer_ = reinterpret_cast<const uint8_t*>(void_buffer); + buffer_end_ = buffer_ + buffer_size; + GOOGLE_CHECK_GE(buffer_size, 0); + + if (total_bytes_read_ <= INT_MAX - buffer_size) { + total_bytes_read_ += buffer_size; + } else { + // Overflow. Reset buffer_end_ to not include the bytes beyond INT_MAX. + // We can't get that far anyway, because total_bytes_limit_ is guaranteed + // to be less than it. We need to keep track of the number of bytes + // we discarded, though, so that we can call input_->BackUp() to back + // up over them on destruction. + + // The following line is equivalent to: + // overflow_bytes_ = total_bytes_read_ + buffer_size - INT_MAX; + // except that it avoids overflows. Signed integer overflow has + // undefined results according to the C standard. + overflow_bytes_ = total_bytes_read_ - (INT_MAX - buffer_size); + buffer_end_ -= overflow_bytes_; + total_bytes_read_ = INT_MAX; + } + + RecomputeBufferLimits(); + return true; + } else { + buffer_ = NULL; + buffer_end_ = NULL; + return false; + } +} + +// CodedOutputStream ================================================= + +void EpsCopyOutputStream::EnableAliasing(bool enabled) { + aliasing_enabled_ = enabled && stream_->AllowsAliasing(); +} + +int64_t EpsCopyOutputStream::ByteCount(uint8_t* ptr) const { + // Calculate the current offset relative to the end of the stream buffer. + int delta = (end_ - ptr) + (buffer_end_ ? 0 : kSlopBytes); + return stream_->ByteCount() - delta; +} + +// Flushes what's written out to the underlying ZeroCopyOutputStream buffers. +// Returns the size remaining in the buffer and sets buffer_end_ to the start +// of the remaining buffer, ie. [buffer_end_, buffer_end_ + return value) +int EpsCopyOutputStream::Flush(uint8_t* ptr) { + while (buffer_end_ && ptr > end_) { + int overrun = ptr - end_; + GOOGLE_DCHECK(!had_error_); + GOOGLE_DCHECK(overrun <= kSlopBytes); // NOLINT + ptr = Next() + overrun; + if (had_error_) return 0; + } + int s; + if (buffer_end_) { + std::memcpy(buffer_end_, buffer_, ptr - buffer_); + buffer_end_ += ptr - buffer_; + s = end_ - ptr; + } else { + // The stream is writing directly in the ZeroCopyOutputStream buffer. + s = end_ + kSlopBytes - ptr; + buffer_end_ = ptr; + } + GOOGLE_DCHECK(s >= 0); // NOLINT + return s; +} + +uint8_t* EpsCopyOutputStream::Trim(uint8_t* ptr) { + if (had_error_) return ptr; + int s = Flush(ptr); + stream_->BackUp(s); + // Reset to initial state (expecting new buffer) + buffer_end_ = end_ = buffer_; + return buffer_; +} + + +uint8_t* EpsCopyOutputStream::FlushAndResetBuffer(uint8_t* ptr) { + if (had_error_) return buffer_; + int s = Flush(ptr); + if (had_error_) return buffer_; + return SetInitialBuffer(buffer_end_, s); +} + +bool EpsCopyOutputStream::Skip(int count, uint8_t** pp) { + if (count < 0) return false; + if (had_error_) { + *pp = buffer_; + return false; + } + int size = Flush(*pp); + if (had_error_) { + *pp = buffer_; + return false; + } + void* data = buffer_end_; + while (count > size) { + count -= size; + if (!stream_->Next(&data, &size)) { + *pp = Error(); + return false; + } + } + *pp = SetInitialBuffer(static_cast<uint8_t*>(data) + count, size - count); + return true; +} + +bool EpsCopyOutputStream::GetDirectBufferPointer(void** data, int* size, + uint8_t** pp) { + if (had_error_) { + *pp = buffer_; + return false; + } + *size = Flush(*pp); + if (had_error_) { + *pp = buffer_; + return false; + } + *data = buffer_end_; + while (*size == 0) { + if (!stream_->Next(data, size)) { + *pp = Error(); + return false; + } + } + *pp = SetInitialBuffer(*data, *size); + return true; +} + +uint8_t* EpsCopyOutputStream::GetDirectBufferForNBytesAndAdvance(int size, + uint8_t** pp) { + if (had_error_) { + *pp = buffer_; + return nullptr; + } + int s = Flush(*pp); + if (had_error_) { + *pp = buffer_; + return nullptr; + } + if (s >= size) { + auto res = buffer_end_; + *pp = SetInitialBuffer(buffer_end_ + size, s - size); + return res; + } else { + *pp = SetInitialBuffer(buffer_end_, s); + return nullptr; + } +} + +uint8_t* EpsCopyOutputStream::Next() { + GOOGLE_DCHECK(!had_error_); // NOLINT + if (PROTOBUF_PREDICT_FALSE(stream_ == nullptr)) return Error(); + if (buffer_end_) { + // We're in the patch buffer and need to fill up the previous buffer. + std::memcpy(buffer_end_, buffer_, end_ - buffer_); + uint8_t* ptr; + int size; + do { + void* data; + if (PROTOBUF_PREDICT_FALSE(!stream_->Next(&data, &size))) { + // Stream has an error, we use the patch buffer to continue to be + // able to write. + return Error(); + } + ptr = static_cast<uint8_t*>(data); + } while (size == 0); + if (PROTOBUF_PREDICT_TRUE(size > kSlopBytes)) { + std::memcpy(ptr, end_, kSlopBytes); + end_ = ptr + size - kSlopBytes; + buffer_end_ = nullptr; + return ptr; + } else { + GOOGLE_DCHECK(size > 0); // NOLINT + // Buffer to small + std::memmove(buffer_, end_, kSlopBytes); + buffer_end_ = ptr; + end_ = buffer_ + size; + return buffer_; + } + } else { + std::memcpy(buffer_, end_, kSlopBytes); + buffer_end_ = end_; + end_ = buffer_ + kSlopBytes; + return buffer_; + } +} + +uint8_t* EpsCopyOutputStream::EnsureSpaceFallback(uint8_t* ptr) { + do { + if (PROTOBUF_PREDICT_FALSE(had_error_)) return buffer_; + int overrun = ptr - end_; + GOOGLE_DCHECK(overrun >= 0); // NOLINT + GOOGLE_DCHECK(overrun <= kSlopBytes); // NOLINT + ptr = Next() + overrun; + } while (ptr >= end_); + GOOGLE_DCHECK(ptr < end_); // NOLINT + return ptr; +} + +uint8_t* EpsCopyOutputStream::WriteRawFallback(const void* data, int size, + uint8_t* ptr) { + int s = GetSize(ptr); + while (s < size) { + std::memcpy(ptr, data, s); + size -= s; + data = static_cast<const uint8_t*>(data) + s; + ptr = EnsureSpaceFallback(ptr + s); + s = GetSize(ptr); + } + std::memcpy(ptr, data, size); + return ptr + size; +} + +uint8_t* EpsCopyOutputStream::WriteAliasedRaw(const void* data, int size, + uint8_t* ptr) { + if (size < GetSize(ptr) + ) { + return WriteRaw(data, size, ptr); + } else { + ptr = Trim(ptr); + if (stream_->WriteAliasedRaw(data, size)) return ptr; + return Error(); + } +} + +#ifndef PROTOBUF_LITTLE_ENDIAN +uint8_t* EpsCopyOutputStream::WriteRawLittleEndian32(const void* data, int size, + uint8_t* ptr) { + auto p = static_cast<const uint8_t*>(data); + auto end = p + size; + while (end - p >= kSlopBytes) { + ptr = EnsureSpace(ptr); + uint32_t buffer[4]; + static_assert(sizeof(buffer) == kSlopBytes, "Buffer must be kSlopBytes"); + std::memcpy(buffer, p, kSlopBytes); + p += kSlopBytes; + for (auto x : buffer) + ptr = CodedOutputStream::WriteLittleEndian32ToArray(x, ptr); + } + while (p < end) { + ptr = EnsureSpace(ptr); + uint32_t buffer; + std::memcpy(&buffer, p, 4); + p += 4; + ptr = CodedOutputStream::WriteLittleEndian32ToArray(buffer, ptr); + } + return ptr; +} + +uint8_t* EpsCopyOutputStream::WriteRawLittleEndian64(const void* data, int size, + uint8_t* ptr) { + auto p = static_cast<const uint8_t*>(data); + auto end = p + size; + while (end - p >= kSlopBytes) { + ptr = EnsureSpace(ptr); + uint64_t buffer[2]; + static_assert(sizeof(buffer) == kSlopBytes, "Buffer must be kSlopBytes"); + std::memcpy(buffer, p, kSlopBytes); + p += kSlopBytes; + for (auto x : buffer) + ptr = CodedOutputStream::WriteLittleEndian64ToArray(x, ptr); + } + while (p < end) { + ptr = EnsureSpace(ptr); + uint64_t buffer; + std::memcpy(&buffer, p, 8); + p += 8; + ptr = CodedOutputStream::WriteLittleEndian64ToArray(buffer, ptr); + } + return ptr; +} +#endif + + +uint8_t* EpsCopyOutputStream::WriteStringMaybeAliasedOutline(uint32_t num, + const std::string& s, + uint8_t* ptr) { + ptr = EnsureSpace(ptr); + uint32_t size = s.size(); + ptr = WriteLengthDelim(num, size, ptr); + return WriteRawMaybeAliased(s.data(), size, ptr); +} + +uint8_t* EpsCopyOutputStream::WriteStringOutline(uint32_t num, const std::string& s, + uint8_t* ptr) { + ptr = EnsureSpace(ptr); + uint32_t size = s.size(); + ptr = WriteLengthDelim(num, size, ptr); + return WriteRaw(s.data(), size, ptr); +} + +std::atomic<bool> CodedOutputStream::default_serialization_deterministic_{ + false}; + +CodedOutputStream::~CodedOutputStream() { Trim(); } + + +uint8_t* CodedOutputStream::WriteStringWithSizeToArray(const std::string& str, + uint8_t* target) { + GOOGLE_DCHECK_LE(str.size(), std::numeric_limits<uint32_t>::max()); + target = WriteVarint32ToArray(str.size(), target); + return WriteStringToArray(str, target); +} + +uint8_t* CodedOutputStream::WriteVarint32ToArrayOutOfLineHelper(uint32_t value, + uint8_t* target) { + GOOGLE_DCHECK_GE(value, 0x80); + target[0] |= static_cast<uint8_t>(0x80); + value >>= 7; + target[1] = static_cast<uint8_t>(value); + if (value < 0x80) { + return target + 2; + } + target += 2; + do { + // Turn on continuation bit in the byte we just wrote. + target[-1] |= static_cast<uint8_t>(0x80); + value >>= 7; + *target = static_cast<uint8_t>(value); + ++target; + } while (value >= 0x80); + return target; +} + +} // namespace io +} // namespace protobuf +} // namespace google + +#include <google/protobuf/port_undef.inc> |