ipc/chromium/src/base/waitable_event_win.cc@6474c204b198 (annotated)
ipc/chromium/src/base/waitable_event_win.cc
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved. |
| michael@0 | 2 | // Use of this source code is governed by a BSD-style license that can be |
| michael@0 | 3 | // found in the LICENSE file. |
| michael@0 | 4 | |
| michael@0 | 5 | #include "base/waitable_event.h" |
| michael@0 | 6 | |
| michael@0 | 7 | #include <math.h> |
| michael@0 | 8 | #include <windows.h> |
| michael@0 | 9 | |
| michael@0 | 10 | #include "base/logging.h" |
| michael@0 | 11 | #include "base/time.h" |
| michael@0 | 12 | |
| michael@0 | 13 | namespace base { |
| michael@0 | 14 | |
| michael@0 | 15 | WaitableEvent::WaitableEvent(bool manual_reset, bool signaled) |
| michael@0 | 16 | : handle_(CreateEvent(NULL, manual_reset, signaled, NULL)) { |
| michael@0 | 17 | // We're probably going to crash anyways if this is ever NULL, so we might as |
| michael@0 | 18 | // well make our stack reports more informative by crashing here. |
| michael@0 | 19 | CHECK(handle_); |
| michael@0 | 20 | } |
| michael@0 | 21 | |
| michael@0 | 22 | WaitableEvent::WaitableEvent(HANDLE handle) |
| michael@0 | 23 | : handle_(handle) { |
| michael@0 | 24 | CHECK(handle) << "Tried to create WaitableEvent from NULL handle"; |
| michael@0 | 25 | } |
| michael@0 | 26 | |
| michael@0 | 27 | WaitableEvent::~WaitableEvent() { |
| michael@0 | 28 | CloseHandle(handle_); |
| michael@0 | 29 | } |
| michael@0 | 30 | |
| michael@0 | 31 | HANDLE WaitableEvent::Release() { |
| michael@0 | 32 | HANDLE rv = handle_; |
| michael@0 | 33 | handle_ = INVALID_HANDLE_VALUE; |
| michael@0 | 34 | return rv; |
| michael@0 | 35 | } |
| michael@0 | 36 | |
| michael@0 | 37 | void WaitableEvent::Reset() { |
| michael@0 | 38 | ResetEvent(handle_); |
| michael@0 | 39 | } |
| michael@0 | 40 | |
| michael@0 | 41 | void WaitableEvent::Signal() { |
| michael@0 | 42 | SetEvent(handle_); |
| michael@0 | 43 | } |
| michael@0 | 44 | |
| michael@0 | 45 | bool WaitableEvent::IsSignaled() { |
| michael@0 | 46 | return TimedWait(TimeDelta::FromMilliseconds(0)); |
| michael@0 | 47 | } |
| michael@0 | 48 | |
| michael@0 | 49 | bool WaitableEvent::Wait() { |
| michael@0 | 50 | DWORD result = WaitForSingleObject(handle_, INFINITE); |
| michael@0 | 51 | // It is most unexpected that this should ever fail. Help consumers learn |
| michael@0 | 52 | // about it if it should ever fail. |
| michael@0 | 53 | DCHECK(result == WAIT_OBJECT_0) << "WaitForSingleObject failed"; |
| michael@0 | 54 | return result == WAIT_OBJECT_0; |
| michael@0 | 55 | } |
| michael@0 | 56 | |
| michael@0 | 57 | bool WaitableEvent::TimedWait(const TimeDelta& max_time) { |
| michael@0 | 58 | DCHECK(max_time >= TimeDelta::FromMicroseconds(0)); |
| michael@0 | 59 | // Be careful here. TimeDelta has a precision of microseconds, but this API |
| michael@0 | 60 | // is in milliseconds. If there are 5.5ms left, should the delay be 5 or 6? |
| michael@0 | 61 | // It should be 6 to avoid returning too early. |
| michael@0 | 62 | double timeout = ceil(max_time.InMillisecondsF()); |
| michael@0 | 63 | DWORD result = WaitForSingleObject(handle_, static_cast<DWORD>(timeout)); |
| michael@0 | 64 | switch (result) { |
| michael@0 | 65 | case WAIT_OBJECT_0: |
| michael@0 | 66 | return true; |
| michael@0 | 67 | case WAIT_TIMEOUT: |
| michael@0 | 68 | return false; |
| michael@0 | 69 | } |
| michael@0 | 70 | // It is most unexpected that this should ever fail. Help consumers learn |
| michael@0 | 71 | // about it if it should ever fail. |
| michael@0 | 72 | NOTREACHED() << "WaitForSingleObject failed"; |
| michael@0 | 73 | return false; |
| michael@0 | 74 | } |
| michael@0 | 75 | |
| michael@0 | 76 | // static |
| michael@0 | 77 | size_t WaitableEvent::WaitMany(WaitableEvent** events, size_t count) { |
| michael@0 | 78 | HANDLE handles[MAXIMUM_WAIT_OBJECTS]; |
| michael@0 | 79 | CHECK(count <= MAXIMUM_WAIT_OBJECTS) |
| michael@0 | 80 | << "Can only wait on " << MAXIMUM_WAIT_OBJECTS << " with WaitMany"; |
| michael@0 | 81 | |
| michael@0 | 82 | for (size_t i = 0; i < count; ++i) |
| michael@0 | 83 | handles[i] = events[i]->handle(); |
| michael@0 | 84 | |
| michael@0 | 85 | DWORD result = |
| michael@0 | 86 | WaitForMultipleObjects(count, handles, |
| michael@0 | 87 | FALSE, // don't wait for all the objects |
| michael@0 | 88 | INFINITE); // no timeout |
| michael@0 | 89 | if (result < WAIT_OBJECT_0 || result >= WAIT_OBJECT_0 + count) { |
| michael@0 | 90 | NOTREACHED() << "WaitForMultipleObjects failed: " << GetLastError(); |
| michael@0 | 91 | return 0; |
| michael@0 | 92 | } |
| michael@0 | 93 | |
| michael@0 | 94 | return result - WAIT_OBJECT_0; |
| michael@0 | 95 | } |
| michael@0 | 96 | |
| michael@0 | 97 | } // namespace base |
