xgboost/src/utils/thread.h
2014-08-29 18:31:24 -07:00

147 lines
3.7 KiB
C++

#ifndef XGBOOST_UTILS_THREAD_H
#define XGBOOST_UTILS_THREAD_H
/*!
* \file thread.h
* \brief this header include the minimum necessary resource for multi-threading
* \author Tianqi Chen
* Acknowledgement: this file is adapted from SVDFeature project, by same author.
* The MAC support part of this code is provided by Artemy Kolchinsky
*/
#ifdef _MSC_VER
#include "utils.h"
#include <windows.h>
#include <process.h>
namespace xgboost {
namespace utils {
/*! \brief simple semaphore used for synchronization */
class Semaphore {
public :
inline void Init(int init_val) {
sem = CreateSemaphore(NULL, init_val, 10, NULL);
utils::Assert(sem != NULL, "create Semaphore error");
}
inline void Destroy(void) {
CloseHandle(sem);
}
inline void Wait(void) {
utils::Assert(WaitForSingleObject(sem, INFINITE) == WAIT_OBJECT_0, "WaitForSingleObject error");
}
inline void Post(void) {
utils::Assert(ReleaseSemaphore(sem, 1, NULL) != 0, "ReleaseSemaphore error");
}
private:
HANDLE sem;
};
/*! \brief simple thread that wraps windows thread */
class Thread {
private:
HANDLE thread_handle;
unsigned thread_id;
public:
inline void Start(unsigned int __stdcall entry(void*), void *param) {
thread_handle = (HANDLE)_beginthreadex(NULL, 0, entry, param, 0, &thread_id);
}
inline int Join(void) {
WaitForSingleObject(thread_handle, INFINITE);
return 0;
}
};
/*! \brief exit function called from thread */
inline void ThreadExit(void *status) {
_endthreadex(0);
}
#define XGBOOST_THREAD_PREFIX unsigned int __stdcall
} // namespace utils
} // namespace xgboost
#else
// thread interface using g++
#include <semaphore.h>
#include <pthread.h>
namespace xgboost {
namespace utils {
/*!\brief semaphore class */
class Semaphore {
#ifdef __APPLE__
private:
sem_t* semPtr;
char sema_name[20];
private:
inline void GenRandomString(char *s, const int len) {
static const char alphanum[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" ;
for (int i = 0; i < len; ++i) {
s[i] = alphanum[rand() % (sizeof(alphanum) - 1)];
}
s[len] = 0;
}
public:
inline void Init(int init_val) {
sema_name[0]='/';
sema_name[1]='s';
sema_name[2]='e';
sema_name[3]='/';
GenRandomString(&sema_name[4], 16);
if((semPtr = sem_open(sema_name, O_CREAT, 0644, init_val)) == SEM_FAILED) {
perror("sem_open");
exit(1);
}
utils::Assert(semPtr != NULL, "create Semaphore error");
}
inline void Destroy(void) {
if (sem_close(semPtr) == -1) {
perror("sem_close");
exit(EXIT_FAILURE);
}
if (sem_unlink(sema_name) == -1) {
perror("sem_unlink");
exit(EXIT_FAILURE);
}
}
inline void Wait(void) {
sem_wait(semPtr);
}
inline void Post(void) {
sem_post(semPtr);
}
#else
private:
sem_t sem;
public:
inline void Init(int init_val) {
sem_init(&sem, 0, init_val);
}
inline void Destroy(void) {
sem_destroy(&sem);
}
inline void Wait(void) {
sem_wait(&sem);
}
inline void Post(void) {
sem_post(&sem);
}
#endif
};
/*!\brief simple thread class */
class Thread {
private:
pthread_t thread;
public :
inline void Start(void * entry(void*), void *param) {
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
pthread_create(&thread, &attr, entry, param);
}
inline int Join(void) {
void *status;
return pthread_join(thread, &status);
}
};
inline void ThreadExit(void *status) {
pthread_exit(status);
}
} // namespace utils
} // namespace xgboost
#define XGBOOST_THREAD_PREFIX void *
#endif
#endif