Index: mojo/edk/system/local_data_pipe.cc |
diff --git a/mojo/edk/system/local_data_pipe.cc b/mojo/edk/system/local_data_pipe.cc |
deleted file mode 100644 |
index 8b9f6735fbd3049780f97e1e083732847e054d95..0000000000000000000000000000000000000000 |
--- a/mojo/edk/system/local_data_pipe.cc |
+++ /dev/null |
@@ -1,350 +0,0 @@ |
-// Copyright 2013 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. |
- |
-// TODO(vtl): I currently potentially overflow in doing index calculations. |
-// E.g., |start_index_| and |current_num_bytes_| fit into a |uint32_t|, but |
-// their sum may not. This is bad and poses a security risk. (We're currently |
-// saved by the limit on capacity -- the maximum size of the buffer, checked in |
-// |DataPipe::ValidateOptions()|, is currently sufficiently small.) |
- |
-#include "mojo/edk/system/local_data_pipe.h" |
- |
-#include <string.h> |
- |
-#include <algorithm> |
- |
-#include "base/logging.h" |
-#include "mojo/edk/system/configuration.h" |
- |
-namespace mojo { |
-namespace system { |
- |
-LocalDataPipe::LocalDataPipe(const MojoCreateDataPipeOptions& options) |
- : DataPipe(true, true, options), start_index_(0), current_num_bytes_(0) { |
- // Note: |buffer_| is lazily allocated, since a common case will be that one |
- // of the handles is immediately passed off to another process. |
-} |
- |
-LocalDataPipe::~LocalDataPipe() { |
-} |
- |
-void LocalDataPipe::ProducerCloseImplNoLock() { |
- // If the consumer is still open and we still have data, we have to keep the |
- // buffer around. Currently, we won't free it even if it empties later. (We |
- // could do this -- requiring a check on every read -- but that seems to be |
- // optimizing for the uncommon case.) |
- if (!consumer_open_no_lock() || !current_num_bytes_) { |
- // Note: There can only be a two-phase *read* (by the consumer) if we still |
- // have data. |
- DCHECK(!consumer_in_two_phase_read_no_lock()); |
- DestroyBufferNoLock(); |
- } |
-} |
- |
-MojoResult LocalDataPipe::ProducerWriteDataImplNoLock( |
- UserPointer<const void> elements, |
- UserPointer<uint32_t> num_bytes, |
- uint32_t max_num_bytes_to_write, |
- uint32_t min_num_bytes_to_write) { |
- DCHECK_EQ(max_num_bytes_to_write % element_num_bytes(), 0u); |
- DCHECK_EQ(min_num_bytes_to_write % element_num_bytes(), 0u); |
- DCHECK_GT(max_num_bytes_to_write, 0u); |
- DCHECK(consumer_open_no_lock()); |
- |
- size_t num_bytes_to_write = 0; |
- if (may_discard()) { |
- if (min_num_bytes_to_write > capacity_num_bytes()) |
- return MOJO_RESULT_OUT_OF_RANGE; |
- |
- num_bytes_to_write = std::min(static_cast<size_t>(max_num_bytes_to_write), |
- capacity_num_bytes()); |
- if (num_bytes_to_write > capacity_num_bytes() - current_num_bytes_) { |
- // Discard as much as needed (discard oldest first). |
- MarkDataAsConsumedNoLock(num_bytes_to_write - |
- (capacity_num_bytes() - current_num_bytes_)); |
- // No need to wake up write waiters, since we're definitely going to leave |
- // the buffer full. |
- } |
- } else { |
- if (min_num_bytes_to_write > capacity_num_bytes() - current_num_bytes_) { |
- // Don't return "should wait" since you can't wait for a specified amount |
- // of data. |
- return MOJO_RESULT_OUT_OF_RANGE; |
- } |
- |
- num_bytes_to_write = std::min(static_cast<size_t>(max_num_bytes_to_write), |
- capacity_num_bytes() - current_num_bytes_); |
- } |
- if (num_bytes_to_write == 0) |
- return MOJO_RESULT_SHOULD_WAIT; |
- |
- // The amount we can write in our first |memcpy()|. |
- size_t num_bytes_to_write_first = |
- std::min(num_bytes_to_write, GetMaxNumBytesToWriteNoLock()); |
- // Do the first (and possibly only) |memcpy()|. |
- size_t first_write_index = |
- (start_index_ + current_num_bytes_) % capacity_num_bytes(); |
- EnsureBufferNoLock(); |
- elements.GetArray(buffer_.get() + first_write_index, |
- num_bytes_to_write_first); |
- |
- if (num_bytes_to_write_first < num_bytes_to_write) { |
- // The "second write index" is zero. |
- elements.At(num_bytes_to_write_first) |
- .GetArray(buffer_.get(), num_bytes_to_write - num_bytes_to_write_first); |
- } |
- |
- current_num_bytes_ += num_bytes_to_write; |
- DCHECK_LE(current_num_bytes_, capacity_num_bytes()); |
- num_bytes.Put(static_cast<uint32_t>(num_bytes_to_write)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ProducerBeginWriteDataImplNoLock( |
- UserPointer<void*> buffer, |
- UserPointer<uint32_t> buffer_num_bytes, |
- uint32_t min_num_bytes_to_write) { |
- DCHECK(consumer_open_no_lock()); |
- |
- // The index we need to start writing at. |
- size_t write_index = |
- (start_index_ + current_num_bytes_) % capacity_num_bytes(); |
- |
- size_t max_num_bytes_to_write = GetMaxNumBytesToWriteNoLock(); |
- if (min_num_bytes_to_write > max_num_bytes_to_write) { |
- // In "may discard" mode, we can always write from the write index to the |
- // end of the buffer. |
- if (may_discard() && |
- min_num_bytes_to_write <= capacity_num_bytes() - write_index) { |
- // To do so, we need to discard an appropriate amount of data. |
- // We should only reach here if the start index is after the write index! |
- DCHECK_GE(start_index_, write_index); |
- DCHECK_GT(min_num_bytes_to_write - max_num_bytes_to_write, 0u); |
- MarkDataAsConsumedNoLock(min_num_bytes_to_write - max_num_bytes_to_write); |
- max_num_bytes_to_write = min_num_bytes_to_write; |
- } else { |
- // Don't return "should wait" since you can't wait for a specified amount |
- // of data. |
- return MOJO_RESULT_OUT_OF_RANGE; |
- } |
- } |
- |
- // Don't go into a two-phase write if there's no room. |
- if (max_num_bytes_to_write == 0) |
- return MOJO_RESULT_SHOULD_WAIT; |
- |
- EnsureBufferNoLock(); |
- buffer.Put(buffer_.get() + write_index); |
- buffer_num_bytes.Put(static_cast<uint32_t>(max_num_bytes_to_write)); |
- set_producer_two_phase_max_num_bytes_written_no_lock( |
- static_cast<uint32_t>(max_num_bytes_to_write)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ProducerEndWriteDataImplNoLock( |
- uint32_t num_bytes_written) { |
- DCHECK_LE(num_bytes_written, |
- producer_two_phase_max_num_bytes_written_no_lock()); |
- current_num_bytes_ += num_bytes_written; |
- DCHECK_LE(current_num_bytes_, capacity_num_bytes()); |
- set_producer_two_phase_max_num_bytes_written_no_lock(0); |
- return MOJO_RESULT_OK; |
-} |
- |
-HandleSignalsState LocalDataPipe::ProducerGetHandleSignalsStateImplNoLock() |
- const { |
- HandleSignalsState rv; |
- if (consumer_open_no_lock()) { |
- if ((may_discard() || current_num_bytes_ < capacity_num_bytes()) && |
- !producer_in_two_phase_write_no_lock()) |
- rv.satisfied_signals |= MOJO_HANDLE_SIGNAL_WRITABLE; |
- rv.satisfiable_signals |= MOJO_HANDLE_SIGNAL_WRITABLE; |
- } else { |
- rv.satisfied_signals |= MOJO_HANDLE_SIGNAL_PEER_CLOSED; |
- } |
- rv.satisfiable_signals |= MOJO_HANDLE_SIGNAL_PEER_CLOSED; |
- return rv; |
-} |
- |
-void LocalDataPipe::ConsumerCloseImplNoLock() { |
- // If the producer is around and in a two-phase write, we have to keep the |
- // buffer around. (We then don't free it until the producer is closed. This |
- // could be rectified, but again seems like optimizing for the uncommon case.) |
- if (!producer_open_no_lock() || !producer_in_two_phase_write_no_lock()) |
- DestroyBufferNoLock(); |
- current_num_bytes_ = 0; |
-} |
- |
-MojoResult LocalDataPipe::ConsumerReadDataImplNoLock( |
- UserPointer<void> elements, |
- UserPointer<uint32_t> num_bytes, |
- uint32_t max_num_bytes_to_read, |
- uint32_t min_num_bytes_to_read, |
- bool peek) { |
- DCHECK_EQ(max_num_bytes_to_read % element_num_bytes(), 0u); |
- DCHECK_EQ(min_num_bytes_to_read % element_num_bytes(), 0u); |
- DCHECK_GT(max_num_bytes_to_read, 0u); |
- |
- if (min_num_bytes_to_read > current_num_bytes_) { |
- // Don't return "should wait" since you can't wait for a specified amount of |
- // data. |
- return producer_open_no_lock() ? MOJO_RESULT_OUT_OF_RANGE |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- size_t num_bytes_to_read = |
- std::min(static_cast<size_t>(max_num_bytes_to_read), current_num_bytes_); |
- if (num_bytes_to_read == 0) { |
- return producer_open_no_lock() ? MOJO_RESULT_SHOULD_WAIT |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- // The amount we can read in our first |memcpy()|. |
- size_t num_bytes_to_read_first = |
- std::min(num_bytes_to_read, GetMaxNumBytesToReadNoLock()); |
- elements.PutArray(buffer_.get() + start_index_, num_bytes_to_read_first); |
- |
- if (num_bytes_to_read_first < num_bytes_to_read) { |
- // The "second read index" is zero. |
- elements.At(num_bytes_to_read_first) |
- .PutArray(buffer_.get(), num_bytes_to_read - num_bytes_to_read_first); |
- } |
- |
- if (!peek) |
- MarkDataAsConsumedNoLock(num_bytes_to_read); |
- num_bytes.Put(static_cast<uint32_t>(num_bytes_to_read)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ConsumerDiscardDataImplNoLock( |
- UserPointer<uint32_t> num_bytes, |
- uint32_t max_num_bytes_to_discard, |
- uint32_t min_num_bytes_to_discard) { |
- DCHECK_EQ(max_num_bytes_to_discard % element_num_bytes(), 0u); |
- DCHECK_EQ(min_num_bytes_to_discard % element_num_bytes(), 0u); |
- DCHECK_GT(max_num_bytes_to_discard, 0u); |
- |
- if (min_num_bytes_to_discard > current_num_bytes_) { |
- // Don't return "should wait" since you can't wait for a specified amount of |
- // data. |
- return producer_open_no_lock() ? MOJO_RESULT_OUT_OF_RANGE |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- // Be consistent with other operations; error if no data available. |
- if (current_num_bytes_ == 0) { |
- return producer_open_no_lock() ? MOJO_RESULT_SHOULD_WAIT |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- size_t num_bytes_to_discard = std::min( |
- static_cast<size_t>(max_num_bytes_to_discard), current_num_bytes_); |
- MarkDataAsConsumedNoLock(num_bytes_to_discard); |
- num_bytes.Put(static_cast<uint32_t>(num_bytes_to_discard)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ConsumerQueryDataImplNoLock( |
- UserPointer<uint32_t> num_bytes) { |
- // Note: This cast is safe, since the capacity fits into a |uint32_t|. |
- num_bytes.Put(static_cast<uint32_t>(current_num_bytes_)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ConsumerBeginReadDataImplNoLock( |
- UserPointer<const void*> buffer, |
- UserPointer<uint32_t> buffer_num_bytes, |
- uint32_t min_num_bytes_to_read) { |
- size_t max_num_bytes_to_read = GetMaxNumBytesToReadNoLock(); |
- if (min_num_bytes_to_read > max_num_bytes_to_read) { |
- // Don't return "should wait" since you can't wait for a specified amount of |
- // data. |
- return producer_open_no_lock() ? MOJO_RESULT_OUT_OF_RANGE |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- // Don't go into a two-phase read if there's no data. |
- if (max_num_bytes_to_read == 0) { |
- return producer_open_no_lock() ? MOJO_RESULT_SHOULD_WAIT |
- : MOJO_RESULT_FAILED_PRECONDITION; |
- } |
- |
- buffer.Put(buffer_.get() + start_index_); |
- buffer_num_bytes.Put(static_cast<uint32_t>(max_num_bytes_to_read)); |
- set_consumer_two_phase_max_num_bytes_read_no_lock( |
- static_cast<uint32_t>(max_num_bytes_to_read)); |
- return MOJO_RESULT_OK; |
-} |
- |
-MojoResult LocalDataPipe::ConsumerEndReadDataImplNoLock( |
- uint32_t num_bytes_read) { |
- DCHECK_LE(num_bytes_read, consumer_two_phase_max_num_bytes_read_no_lock()); |
- DCHECK_LE(start_index_ + num_bytes_read, capacity_num_bytes()); |
- MarkDataAsConsumedNoLock(num_bytes_read); |
- set_consumer_two_phase_max_num_bytes_read_no_lock(0); |
- return MOJO_RESULT_OK; |
-} |
- |
-HandleSignalsState LocalDataPipe::ConsumerGetHandleSignalsStateImplNoLock() |
- const { |
- HandleSignalsState rv; |
- if (current_num_bytes_ > 0) { |
- if (!consumer_in_two_phase_read_no_lock()) |
- rv.satisfied_signals |= MOJO_HANDLE_SIGNAL_READABLE; |
- rv.satisfiable_signals |= MOJO_HANDLE_SIGNAL_READABLE; |
- } else if (producer_open_no_lock()) { |
- rv.satisfiable_signals |= MOJO_HANDLE_SIGNAL_READABLE; |
- } |
- if (!producer_open_no_lock()) |
- rv.satisfied_signals |= MOJO_HANDLE_SIGNAL_PEER_CLOSED; |
- rv.satisfiable_signals |= MOJO_HANDLE_SIGNAL_PEER_CLOSED; |
- return rv; |
-} |
- |
-void LocalDataPipe::EnsureBufferNoLock() { |
- DCHECK(producer_open_no_lock()); |
- if (buffer_) |
- return; |
- buffer_.reset(static_cast<char*>( |
- base::AlignedAlloc(capacity_num_bytes(), |
- GetConfiguration().data_pipe_buffer_alignment_bytes))); |
-} |
- |
-void LocalDataPipe::DestroyBufferNoLock() { |
-#ifndef NDEBUG |
- // Scribble on the buffer to help detect use-after-frees. (This also helps the |
- // unit test detect certain bugs without needing ASAN or similar.) |
- if (buffer_) |
- memset(buffer_.get(), 0xcd, capacity_num_bytes()); |
-#endif |
- buffer_.reset(); |
-} |
- |
-size_t LocalDataPipe::GetMaxNumBytesToWriteNoLock() { |
- size_t next_index = start_index_ + current_num_bytes_; |
- if (next_index >= capacity_num_bytes()) { |
- next_index %= capacity_num_bytes(); |
- DCHECK_GE(start_index_, next_index); |
- DCHECK_EQ(start_index_ - next_index, |
- capacity_num_bytes() - current_num_bytes_); |
- return start_index_ - next_index; |
- } |
- return capacity_num_bytes() - next_index; |
-} |
- |
-size_t LocalDataPipe::GetMaxNumBytesToReadNoLock() { |
- if (start_index_ + current_num_bytes_ > capacity_num_bytes()) |
- return capacity_num_bytes() - start_index_; |
- return current_num_bytes_; |
-} |
- |
-void LocalDataPipe::MarkDataAsConsumedNoLock(size_t num_bytes) { |
- DCHECK_LE(num_bytes, current_num_bytes_); |
- start_index_ += num_bytes; |
- start_index_ %= capacity_num_bytes(); |
- current_num_bytes_ -= num_bytes; |
-} |
- |
-} // namespace system |
-} // namespace mojo |