henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 1 | /* |
| 2 | * libjingle |
| 3 | * Copyright 2004, Google Inc. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright notice, |
| 9 | * this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| 11 | * this list of conditions and the following disclaimer in the documentation |
| 12 | * and/or other materials provided with the distribution. |
| 13 | * 3. The name of the author may not be used to endorse or promote products |
| 14 | * derived from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 17 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 18 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
| 19 | * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 20 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 21 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 22 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 23 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| 24 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| 25 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #ifndef TALK_BASE_CRITICALSECTION_H__ |
| 29 | #define TALK_BASE_CRITICALSECTION_H__ |
| 30 | |
| 31 | #include "talk/base/constructormagic.h" |
| 32 | |
| 33 | #ifdef WIN32 |
| 34 | #include "talk/base/win32.h" |
| 35 | #endif |
| 36 | |
| 37 | #ifdef POSIX |
| 38 | #include <pthread.h> |
| 39 | #endif |
| 40 | |
| 41 | #ifdef _DEBUG |
| 42 | #define CS_TRACK_OWNER 1 |
| 43 | #endif // _DEBUG |
| 44 | |
| 45 | #if CS_TRACK_OWNER |
| 46 | #define TRACK_OWNER(x) x |
| 47 | #else // !CS_TRACK_OWNER |
| 48 | #define TRACK_OWNER(x) |
| 49 | #endif // !CS_TRACK_OWNER |
| 50 | |
| 51 | namespace talk_base { |
| 52 | |
| 53 | #ifdef WIN32 |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 54 | class CriticalSection { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 55 | public: |
| 56 | CriticalSection() { |
| 57 | InitializeCriticalSection(&crit_); |
| 58 | // Windows docs say 0 is not a valid thread id |
| 59 | TRACK_OWNER(thread_ = 0); |
| 60 | } |
| 61 | ~CriticalSection() { |
| 62 | DeleteCriticalSection(&crit_); |
| 63 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 64 | void Enter() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 65 | EnterCriticalSection(&crit_); |
| 66 | TRACK_OWNER(thread_ = GetCurrentThreadId()); |
| 67 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 68 | bool TryEnter() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 69 | if (TryEnterCriticalSection(&crit_) != FALSE) { |
| 70 | TRACK_OWNER(thread_ = GetCurrentThreadId()); |
| 71 | return true; |
| 72 | } |
| 73 | return false; |
| 74 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 75 | void Leave() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 76 | TRACK_OWNER(thread_ = 0); |
| 77 | LeaveCriticalSection(&crit_); |
| 78 | } |
| 79 | |
| 80 | #if CS_TRACK_OWNER |
| 81 | bool CurrentThreadIsOwner() const { return thread_ == GetCurrentThreadId(); } |
| 82 | #endif // CS_TRACK_OWNER |
| 83 | |
| 84 | private: |
| 85 | CRITICAL_SECTION crit_; |
| 86 | TRACK_OWNER(DWORD thread_); // The section's owning thread id |
| 87 | }; |
| 88 | #endif // WIN32 |
| 89 | |
| 90 | #ifdef POSIX |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 91 | class CriticalSection { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 92 | public: |
| 93 | CriticalSection() { |
| 94 | pthread_mutexattr_t mutex_attribute; |
| 95 | pthread_mutexattr_init(&mutex_attribute); |
| 96 | pthread_mutexattr_settype(&mutex_attribute, PTHREAD_MUTEX_RECURSIVE); |
| 97 | pthread_mutex_init(&mutex_, &mutex_attribute); |
| 98 | pthread_mutexattr_destroy(&mutex_attribute); |
| 99 | TRACK_OWNER(thread_ = 0); |
| 100 | } |
| 101 | ~CriticalSection() { |
| 102 | pthread_mutex_destroy(&mutex_); |
| 103 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 104 | void Enter() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 105 | pthread_mutex_lock(&mutex_); |
| 106 | TRACK_OWNER(thread_ = pthread_self()); |
| 107 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 108 | bool TryEnter() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 109 | if (pthread_mutex_trylock(&mutex_) == 0) { |
| 110 | TRACK_OWNER(thread_ = pthread_self()); |
| 111 | return true; |
| 112 | } |
| 113 | return false; |
| 114 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 115 | void Leave() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 116 | TRACK_OWNER(thread_ = 0); |
| 117 | pthread_mutex_unlock(&mutex_); |
| 118 | } |
| 119 | |
| 120 | #if CS_TRACK_OWNER |
| 121 | bool CurrentThreadIsOwner() const { return pthread_equal(thread_, pthread_self()); } |
| 122 | #endif // CS_TRACK_OWNER |
| 123 | |
| 124 | private: |
| 125 | pthread_mutex_t mutex_; |
| 126 | TRACK_OWNER(pthread_t thread_); |
| 127 | }; |
| 128 | #endif // POSIX |
| 129 | |
| 130 | // CritScope, for serializing execution through a scope. |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 131 | class CritScope { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 132 | public: |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 133 | explicit CritScope(CriticalSection *pcrit) { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 134 | pcrit_ = pcrit; |
| 135 | pcrit_->Enter(); |
| 136 | } |
wjia@webrtc.org | ee78a38 | 2014-02-10 23:20:15 +0000 | [diff] [blame] | 137 | ~CritScope() { |
henrike@webrtc.org | 0e118e7 | 2013-07-10 00:45:36 +0000 | [diff] [blame] | 138 | pcrit_->Leave(); |
| 139 | } |
| 140 | private: |
| 141 | CriticalSection *pcrit_; |
| 142 | DISALLOW_COPY_AND_ASSIGN(CritScope); |
| 143 | }; |
| 144 | |
| 145 | // Tries to lock a critical section on construction via |
| 146 | // CriticalSection::TryEnter, and unlocks on destruction if the |
| 147 | // lock was taken. Never blocks. |
| 148 | // |
| 149 | // IMPORTANT: Unlike CritScope, the lock may not be owned by this thread in |
| 150 | // subsequent code. Users *must* check locked() to determine if the |
| 151 | // lock was taken. If you're not calling locked(), you're doing it wrong! |
| 152 | class TryCritScope { |
| 153 | public: |
| 154 | explicit TryCritScope(CriticalSection *pcrit) { |
| 155 | pcrit_ = pcrit; |
| 156 | locked_ = pcrit_->TryEnter(); |
| 157 | } |
| 158 | ~TryCritScope() { |
| 159 | if (locked_) { |
| 160 | pcrit_->Leave(); |
| 161 | } |
| 162 | } |
| 163 | bool locked() const { |
| 164 | return locked_; |
| 165 | } |
| 166 | private: |
| 167 | CriticalSection *pcrit_; |
| 168 | bool locked_; |
| 169 | DISALLOW_COPY_AND_ASSIGN(TryCritScope); |
| 170 | }; |
| 171 | |
| 172 | // TODO: Move this to atomicops.h, which can't be done easily because of |
| 173 | // complex compile rules. |
| 174 | class AtomicOps { |
| 175 | public: |
| 176 | #ifdef WIN32 |
| 177 | // Assumes sizeof(int) == sizeof(LONG), which it is on Win32 and Win64. |
| 178 | static int Increment(int* i) { |
| 179 | return ::InterlockedIncrement(reinterpret_cast<LONG*>(i)); |
| 180 | } |
| 181 | static int Decrement(int* i) { |
| 182 | return ::InterlockedDecrement(reinterpret_cast<LONG*>(i)); |
| 183 | } |
| 184 | #else |
| 185 | static int Increment(int* i) { |
| 186 | return __sync_add_and_fetch(i, 1); |
| 187 | } |
| 188 | static int Decrement(int* i) { |
| 189 | return __sync_sub_and_fetch(i, 1); |
| 190 | } |
| 191 | #endif |
| 192 | }; |
| 193 | |
| 194 | } // namespace talk_base |
| 195 | |
| 196 | #endif // TALK_BASE_CRITICALSECTION_H__ |