| File: | out/../deps/v8/src/base/platform/condition-variable.cc |
| Warning: | line 102, column 3 Value stored to 'result' is never read |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
| 1 | // Copyright 2013 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/base/platform/condition-variable.h" |
| 6 | |
| 7 | #include <errno(*__errno_location ()).h> |
| 8 | #include <time.h> |
| 9 | |
| 10 | #include "src/base/platform/time.h" |
| 11 | |
| 12 | #if V8_OS_WIN |
| 13 | #include <windows.h> |
| 14 | #endif |
| 15 | |
| 16 | namespace v8 { |
| 17 | namespace base { |
| 18 | |
| 19 | #if V8_OS_POSIX1 |
| 20 | |
| 21 | ConditionVariable::ConditionVariable() { |
| 22 | #if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || \ |
| 23 | (V8_OS_LINUX1 && V8_LIBC_GLIBC1)) |
| 24 | // On Free/Net/OpenBSD and Linux with glibc we can change the time |
| 25 | // source for pthread_cond_timedwait() to use the monotonic clock. |
| 26 | pthread_condattr_t attr; |
| 27 | int result = pthread_condattr_init(&attr); |
| 28 | DCHECK_EQ(0, result)((void) 0); |
| 29 | result = pthread_condattr_setclock(&attr, CLOCK_MONOTONIC1); |
| 30 | DCHECK_EQ(0, result)((void) 0); |
| 31 | result = pthread_cond_init(&native_handle_, &attr); |
| 32 | DCHECK_EQ(0, result)((void) 0); |
| 33 | result = pthread_condattr_destroy(&attr); |
| 34 | #else |
| 35 | int result = pthread_cond_init(&native_handle_, nullptr); |
| 36 | #endif |
| 37 | DCHECK_EQ(0, result)((void) 0); |
| 38 | USE(result)do { ::v8::base::Use unused_tmp_array_for_use_macro[]{result} ; (void)unused_tmp_array_for_use_macro; } while (false); |
| 39 | } |
| 40 | |
| 41 | |
| 42 | ConditionVariable::~ConditionVariable() { |
| 43 | #if defined(V8_OS_DARWIN) |
| 44 | // This hack is necessary to avoid a fatal pthreads subsystem bug in the |
| 45 | // Darwin kernel. http://crbug.com/517681. |
| 46 | { |
| 47 | Mutex lock; |
| 48 | MutexGuard l(&lock); |
| 49 | struct timespec ts; |
| 50 | ts.tv_sec = 0; |
| 51 | ts.tv_nsec = 1; |
| 52 | pthread_cond_timedwait_relative_np(&native_handle_, &lock.native_handle(), |
| 53 | &ts); |
| 54 | } |
| 55 | #endif |
| 56 | int result = pthread_cond_destroy(&native_handle_); |
| 57 | DCHECK_EQ(0, result)((void) 0); |
| 58 | USE(result)do { ::v8::base::Use unused_tmp_array_for_use_macro[]{result} ; (void)unused_tmp_array_for_use_macro; } while (false); |
| 59 | } |
| 60 | |
| 61 | |
| 62 | void ConditionVariable::NotifyOne() { |
| 63 | int result = pthread_cond_signal(&native_handle_); |
| 64 | DCHECK_EQ(0, result)((void) 0); |
| 65 | USE(result)do { ::v8::base::Use unused_tmp_array_for_use_macro[]{result} ; (void)unused_tmp_array_for_use_macro; } while (false); |
| 66 | } |
| 67 | |
| 68 | |
| 69 | void ConditionVariable::NotifyAll() { |
| 70 | int result = pthread_cond_broadcast(&native_handle_); |
| 71 | DCHECK_EQ(0, result)((void) 0); |
| 72 | USE(result)do { ::v8::base::Use unused_tmp_array_for_use_macro[]{result} ; (void)unused_tmp_array_for_use_macro; } while (false); |
| 73 | } |
| 74 | |
| 75 | |
| 76 | void ConditionVariable::Wait(Mutex* mutex) { |
| 77 | mutex->AssertHeldAndUnmark(); |
| 78 | int result = pthread_cond_wait(&native_handle_, &mutex->native_handle()); |
| 79 | DCHECK_EQ(0, result)((void) 0); |
| 80 | USE(result)do { ::v8::base::Use unused_tmp_array_for_use_macro[]{result} ; (void)unused_tmp_array_for_use_macro; } while (false); |
| 81 | mutex->AssertUnheldAndMark(); |
| 82 | } |
| 83 | |
| 84 | |
| 85 | bool ConditionVariable::WaitFor(Mutex* mutex, const TimeDelta& rel_time) { |
| 86 | struct timespec ts; |
| 87 | int result; |
| 88 | mutex->AssertHeldAndUnmark(); |
| 89 | #if V8_OS_DARWIN |
| 90 | // Mac OS X provides pthread_cond_timedwait_relative_np(), which does |
| 91 | // not depend on the real time clock, which is what you really WANT here! |
| 92 | ts = rel_time.ToTimespec(); |
| 93 | DCHECK_GE(ts.tv_sec, 0)((void) 0); |
| 94 | DCHECK_GE(ts.tv_nsec, 0)((void) 0); |
| 95 | result = pthread_cond_timedwait_relative_np( |
| 96 | &native_handle_, &mutex->native_handle(), &ts); |
| 97 | #else |
| 98 | #if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || \ |
| 99 | (V8_OS_LINUX1 && V8_LIBC_GLIBC1)) |
| 100 | // On Free/Net/OpenBSD and Linux with glibc we can change the time |
| 101 | // source for pthread_cond_timedwait() to use the monotonic clock. |
| 102 | result = clock_gettime(CLOCK_MONOTONIC1, &ts); |
Value stored to 'result' is never read | |
| 103 | DCHECK_EQ(0, result)((void) 0); |
| 104 | Time now = Time::FromTimespec(ts); |
| 105 | #else |
| 106 | // The timeout argument to pthread_cond_timedwait() is in absolute time. |
| 107 | Time now = Time::NowFromSystemTime(); |
| 108 | #endif |
| 109 | Time end_time = now + rel_time; |
| 110 | DCHECK_GE(end_time, now)((void) 0); |
| 111 | ts = end_time.ToTimespec(); |
| 112 | result = pthread_cond_timedwait( |
| 113 | &native_handle_, &mutex->native_handle(), &ts); |
| 114 | #endif // V8_OS_DARWIN |
| 115 | mutex->AssertUnheldAndMark(); |
| 116 | if (result == ETIMEDOUT110) { |
| 117 | return false; |
| 118 | } |
| 119 | DCHECK_EQ(0, result)((void) 0); |
| 120 | return true; |
| 121 | } |
| 122 | |
| 123 | #elif V8_OS_WIN |
| 124 | |
| 125 | ConditionVariable::ConditionVariable() { |
| 126 | InitializeConditionVariable(V8ToWindowsType(&native_handle_)); |
| 127 | } |
| 128 | |
| 129 | |
| 130 | ConditionVariable::~ConditionVariable() {} |
| 131 | |
| 132 | void ConditionVariable::NotifyOne() { |
| 133 | WakeConditionVariable(V8ToWindowsType(&native_handle_)); |
| 134 | } |
| 135 | |
| 136 | void ConditionVariable::NotifyAll() { |
| 137 | WakeAllConditionVariable(V8ToWindowsType(&native_handle_)); |
| 138 | } |
| 139 | |
| 140 | |
| 141 | void ConditionVariable::Wait(Mutex* mutex) { |
| 142 | mutex->AssertHeldAndUnmark(); |
| 143 | SleepConditionVariableSRW(V8ToWindowsType(&native_handle_), |
| 144 | V8ToWindowsType(&mutex->native_handle()), INFINITE, |
| 145 | 0); |
| 146 | mutex->AssertUnheldAndMark(); |
| 147 | } |
| 148 | |
| 149 | |
| 150 | bool ConditionVariable::WaitFor(Mutex* mutex, const TimeDelta& rel_time) { |
| 151 | int64_t msec = rel_time.InMilliseconds(); |
| 152 | mutex->AssertHeldAndUnmark(); |
| 153 | BOOL result = SleepConditionVariableSRW( |
| 154 | V8ToWindowsType(&native_handle_), |
| 155 | V8ToWindowsType(&mutex->native_handle()), static_cast<DWORD>(msec), 0); |
| 156 | #ifdef DEBUG |
| 157 | if (!result) { |
| 158 | // On failure, we only expect the CV to timeout. Any other error value means |
| 159 | // that we've unexpectedly woken up. |
| 160 | // Note that WAIT_TIMEOUT != ERROR_TIMEOUT. WAIT_TIMEOUT is used with the |
| 161 | // WaitFor* family of functions as a direct return value. ERROR_TIMEOUT is |
| 162 | // used with GetLastError(). |
| 163 | DCHECK_EQ(static_cast<DWORD>(ERROR_TIMEOUT), GetLastError())((void) 0); |
| 164 | } |
| 165 | #endif |
| 166 | mutex->AssertUnheldAndMark(); |
| 167 | return result != 0; |
| 168 | } |
| 169 | |
| 170 | #elif V8_OS_STARBOARD |
| 171 | |
| 172 | ConditionVariable::ConditionVariable() { |
| 173 | SbConditionVariableCreate(&native_handle_, nullptr); |
| 174 | } |
| 175 | |
| 176 | ConditionVariable::~ConditionVariable() { |
| 177 | SbConditionVariableDestroy(&native_handle_); |
| 178 | } |
| 179 | |
| 180 | void ConditionVariable::NotifyOne() { |
| 181 | SbConditionVariableSignal(&native_handle_); |
| 182 | } |
| 183 | |
| 184 | void ConditionVariable::NotifyAll() { |
| 185 | SbConditionVariableBroadcast(&native_handle_); |
| 186 | } |
| 187 | |
| 188 | void ConditionVariable::Wait(Mutex* mutex) { |
| 189 | SbConditionVariableWait(&native_handle_, &mutex->native_handle()); |
| 190 | } |
| 191 | |
| 192 | bool ConditionVariable::WaitFor(Mutex* mutex, const TimeDelta& rel_time) { |
| 193 | SbTime microseconds = static_cast<SbTime>(rel_time.InMicroseconds()); |
| 194 | SbConditionVariableResult result = SbConditionVariableWaitTimed( |
| 195 | &native_handle_, &mutex->native_handle(), microseconds); |
| 196 | DCHECK(result != kSbConditionVariableFailed)((void) 0); |
| 197 | return result == kSbConditionVariableSignaled; |
| 198 | } |
| 199 | |
| 200 | #endif // V8_OS_STARBOARD |
| 201 | |
| 202 | } // namespace base |
| 203 | } // namespace v8 |