ppsspp/base/mutex.h

340 lines
6.8 KiB
C++

#pragma once
// Simple cross platform mutex implementation.
// Similar to the new C++11 api.
// Windows and pthreads implementations in one.
// TODO: Need to clean up these primitives and put them in a reasonable namespace.
#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#define NOMINMAX
#include <windows.h>
#include <limits.h>
#include <intrin.h>
// Zap stupid windows defines
// Should move these somewhere clever.
#undef p
#undef DrawText
#undef itoa
#else
#include <pthread.h>
#include <errno.h>
#include <sys/time.h>
#ifdef BLACKBERRY
#include <atomic.h>
#elif defined(__SYMBIAN32__)
#include <glib/gatomic.h>
#endif
#endif
#include "base/basictypes.h"
struct atomic_flag_init {
atomic_flag_init() : v(false) {
}
bool v;
};
static const atomic_flag_init NATIVE_ATOMIC_FLAG_INIT;
class atomic_flag {
public:
atomic_flag() {
}
atomic_flag(const atomic_flag_init &v) : value(0) {
}
void clear() {
#if defined(_WIN32)
_WriteBarrier();
value = 0;
#elif defined(BLACKBERRY)
atomic_clr(&value, 1);
#elif defined(__SYMBIAN32__)
g_atomic_int_set(&value, 0);
#else
__sync_lock_release(&value);
#endif
}
// Returns the previous value.
bool test_and_set() {
#if defined(_WIN32)
return InterlockedExchange(&value, 1) != 0;
#elif defined(BLACKBERRY)
return atomic_set_value(&value, 1) != 0;
#elif defined(__SYMBIAN32__)
return !g_atomic_int_compare_and_exchange((volatile int*)&value, 0, 1);
#else
return __sync_lock_test_and_set(&value, 1) != 0;
#endif
}
private:
volatile unsigned int value;
DISALLOW_COPY_AND_ASSIGN(atomic_flag);
};
class recursive_mutex {
#ifdef _WIN32
typedef CRITICAL_SECTION mutexType;
#else
typedef pthread_mutex_t mutexType;
#endif
public:
recursive_mutex() {
#ifdef _WIN32
InitializeCriticalSection(&mut_);
#else
// Critical sections are recursive so let's make these recursive too.
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
pthread_mutex_init(&mut_, &attr);
#endif
}
~recursive_mutex() {
#ifdef _WIN32
DeleteCriticalSection(&mut_);
#else
pthread_mutex_destroy(&mut_);
#endif
}
bool trylock() {
#ifdef _WIN32
return TryEnterCriticalSection(&mut_) == TRUE;
#else
return pthread_mutex_trylock(&mut_) != EBUSY;
#endif
}
void lock() {
#ifdef _WIN32
EnterCriticalSection(&mut_);
#else
pthread_mutex_lock(&mut_);
#endif
}
void unlock() {
#ifdef _WIN32
LeaveCriticalSection(&mut_);
#else
pthread_mutex_unlock(&mut_);
#endif
}
mutexType &native_handle() {
return mut_;
}
private:
mutexType mut_;
recursive_mutex(const recursive_mutex &other);
};
class lock_guard {
public:
lock_guard(recursive_mutex &mtx) : mtx_(mtx) {mtx_.lock();}
~lock_guard() {mtx_.unlock();}
private:
recursive_mutex &mtx_;
};
// Like a Windows event, or a modern condition variable.
class event {
public:
#ifdef _WIN32
#else
#endif
event() {
#ifdef _WIN32
event_ = CreateEvent(0, FALSE, FALSE, 0);
#else
pthread_cond_init(&event_, NULL);
#endif
}
~event() {
#ifdef _WIN32
CloseHandle(event_);
#else
pthread_cond_destroy(&event_);
#endif
}
void notify_one() {
#ifdef _WIN32
SetEvent(event_);
#else
pthread_cond_signal(&event_);
#endif
}
// notify_all is not really possible to implement with win32 events?
void wait(recursive_mutex &mtx) {
// broken
#ifdef _WIN32
// This has to be horribly racy.
mtx.lock();
WaitForSingleObject(event_, INFINITE);
ResetEvent(event_); // necessary?
mtx.unlock();
#else
pthread_mutex_lock(&mtx.native_handle());
pthread_cond_wait(&event_, &mtx.native_handle());
pthread_mutex_unlock(&mtx.native_handle());
#endif
}
void wait_for(recursive_mutex &mtx, int milliseconds) {
#ifdef _WIN32
//mtx.unlock();
WaitForSingleObject(event_, milliseconds);
ResetEvent(event_); // necessary?
// mtx.lock();
#else
timespec timeout;
#ifdef __APPLE__
timeval tv;
gettimeofday(&tv, NULL);
timeout.tv_sec = tv.tv_sec;
timeout.tv_nsec = tv.tv_usec * 1000;
#else
clock_gettime(CLOCK_REALTIME, &timeout);
#endif
timeout.tv_sec += milliseconds / 1000;
timeout.tv_nsec += milliseconds * 1000000;
pthread_mutex_lock(&mtx.native_handle());
pthread_cond_timedwait(&event_, &mtx.native_handle(), &timeout);
pthread_mutex_unlock(&mtx.native_handle());
#endif
}
void reset() {
#ifdef _WIN32
ResetEvent(event_);
#endif
}
private:
#ifdef _WIN32
HANDLE event_;
#else
pthread_cond_t event_;
#endif
};
// Win32 CONDITION_VARIABLE is Vista+ only. We thus limit it to our 64-bit builds where
// we can be almost certain that the user isn't running XP.
class condition_variable {
public:
#ifdef _WIN32
#else
#endif
condition_variable() {
#ifdef _WIN32
#ifdef _WIN64
InitializeConditionVariable(&cond_);
#else
sema_ = CreateSemaphore(NULL, 0, LONG_MAX, NULL);
#endif
#else
pthread_cond_init(&event_, NULL);
#endif
}
~condition_variable() {
#ifdef _WIN32
#ifdef _WIN64
#else
CloseHandle(sema_);
#endif
#else
pthread_cond_destroy(&event_);
#endif
}
void notify_one() {
#ifdef _WIN32
#ifdef _M_X64
WakeConditionVariable(&cond_);
#else
ReleaseSemaphore(sema_, 1, NULL);
#endif
#else
pthread_cond_signal(&event_);
#endif
}
// notify_all is not really possible to implement with win32 events?
// Can be done just fine using WakeAllConditionVariable though.
void wait(recursive_mutex &mtx) {
// broken http://msdn.microsoft.com/en-us/library/windows/desktop/ms686301(v=vs.85).aspx
#ifdef _WIN32
#ifdef _M_X64
SleepConditionVariableCS(&cond_, &mtx.native_handle(), INFINITE);
#else
// Since a semaphore keeps a count, the window between unlock and lock won't cause us to deadlock.
// However, we could wake early incorrectly (if the semaphore is signalled already.)
// That's better than deadlocking or forgetting to wake.
mtx.unlock();
WaitForSingleObject(sema_, INFINITE);
mtx.lock();
#endif
#else
pthread_cond_wait(&event_, &mtx.native_handle());
#endif
}
void wait_for(recursive_mutex &mtx, int milliseconds) {
#ifdef _WIN32
#ifdef _M_X64
SleepConditionVariableCS(&cond_, &mtx.native_handle(), milliseconds);
#else
// Since a semaphore keeps a count, the window between unlock and lock won't cause us to deadlock.
// However, we could wake early incorrectly (if the semaphore is signalled already.)
// That's better than deadlocking or forgetting to wake.
mtx.unlock();
WaitForSingleObject(sema_, milliseconds);
mtx.lock();
#endif
#else
timespec timeout;
#ifdef __APPLE__
timeval tv;
gettimeofday(&tv, NULL);
timeout.tv_sec = tv.tv_sec;
timeout.tv_nsec = tv.tv_usec * 1000;
#else
clock_gettime(CLOCK_REALTIME, &timeout);
#endif
timeout.tv_sec += milliseconds / 1000;
timeout.tv_nsec += milliseconds * 1000000;
pthread_cond_timedwait(&event_, &mtx.native_handle(), &timeout);
#endif
}
private:
#ifdef _WIN32
#ifdef _M_X64
CONDITION_VARIABLE cond_;
#else
HANDLE sema_;
#endif
#else
pthread_cond_t event_;
#endif
};