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/*
* Copyright (c) 2014 - 2016, The Linux Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted
* provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other materials provided
* with the distribution.
* * Neither the name of The Linux Foundation nor the names of its contributors may be used to
* endorse or promote products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __LOCKER_H__
#define __LOCKER_H__
#include <stdint.h>
#include <pthread.h>
#include <sys/time.h>
#define SCOPE_LOCK(locker) Locker::ScopeLock lock(locker)
#define SEQUENCE_ENTRY_SCOPE_LOCK(locker) Locker::SequenceEntryScopeLock lock(locker)
#define SEQUENCE_EXIT_SCOPE_LOCK(locker) Locker::SequenceExitScopeLock lock(locker)
#define SEQUENCE_WAIT_SCOPE_LOCK(locker) Locker::SequenceWaitScopeLock lock(locker)
#define SEQUENCE_CANCEL_SCOPE_LOCK(locker) Locker::SequenceCancelScopeLock lock(locker)
namespace sdm {
class Locker {
public:
class ScopeLock {
public:
explicit ScopeLock(Locker& locker) : locker_(locker) {
locker_.Lock();
}
~ScopeLock() {
locker_.Unlock();
}
private:
Locker &locker_;
};
class SequenceEntryScopeLock {
public:
explicit SequenceEntryScopeLock(Locker& locker) : locker_(locker) {
locker_.Lock();
locker_.sequence_wait_ = 1;
}
~SequenceEntryScopeLock() {
locker_.Unlock();
}
private:
Locker &locker_;
};
class SequenceExitScopeLock {
public:
explicit SequenceExitScopeLock(Locker& locker) : locker_(locker) {
locker_.Lock();
locker_.sequence_wait_ = 0;
}
~SequenceExitScopeLock() {
locker_.Broadcast();
locker_.Unlock();
}
private:
Locker &locker_;
};
class SequenceWaitScopeLock {
public:
explicit SequenceWaitScopeLock(Locker& locker) : locker_(locker), error_(false) {
locker_.Lock();
while (locker_.sequence_wait_ == 1) {
locker_.Wait();
error_ = (locker_.sequence_wait_ == -1);
}
}
~SequenceWaitScopeLock() {
locker_.Unlock();
}
bool IsError() {
return error_;
}
private:
Locker &locker_;
bool error_;
};
class SequenceCancelScopeLock {
public:
explicit SequenceCancelScopeLock(Locker& locker) : locker_(locker) {
locker_.Lock();
locker_.sequence_wait_ = -1;
}
~SequenceCancelScopeLock() {
locker_.Broadcast();
locker_.Unlock();
}
private:
Locker &locker_;
};
Locker() : sequence_wait_(0) {
pthread_mutex_init(&mutex_, 0);
pthread_cond_init(&condition_, 0);
}
~Locker() {
pthread_mutex_destroy(&mutex_);
pthread_cond_destroy(&condition_);
}
void Lock() { pthread_mutex_lock(&mutex_); }
void Unlock() { pthread_mutex_unlock(&mutex_); }
void Signal() { pthread_cond_signal(&condition_); }
void Broadcast() { pthread_cond_broadcast(&condition_); }
void Wait() { pthread_cond_wait(&condition_, &mutex_); }
int WaitFinite(int ms) {
struct timespec ts;
struct timeval tv;
gettimeofday(&tv, NULL);
ts.tv_sec = tv.tv_sec + ms/1000;
ts.tv_nsec = tv.tv_usec*1000 + (ms%1000)*1000000;
ts.tv_sec += ts.tv_nsec/1000000000L;
ts.tv_nsec %= 1000000000L;
return pthread_cond_timedwait(&condition_, &mutex_, &ts);
}
private:
pthread_mutex_t mutex_;
pthread_cond_t condition_;
int sequence_wait_; // This flag is set to 1 on sequence entry, 0 on exit, and -1 on cancel.
// Some routines will wait for sequence of function calls to finish
// so that capturing a transitionary snapshot of context is prevented.
// If flag is set to -1, these routines will exit without doing any
// further processing.
};
} // namespace sdm
#endif // __LOCKER_H__
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