gdk_system.h

这个是内存数据库中的一个管理工具

#ifndef _GDK_SYSTEM_H_
#define _GDK_SYSTEM_H_

#ifdef NATIVE_WIN32
#ifndef LIBGDK
#define gdk_export extern __declspec(dllimport)
#else
#define gdk_export extern __declspec(dllexport)
#endif
#else
#define gdk_export extern
#endif

#ifdef HAVE_UNISTD_H
# include <unistd.h>		/* io functions */
#endif
#ifdef HAVE_IO_H
# include <io.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif



#include <sys/types.h>
#ifdef HAVE_SIGNAL_H
# include <signal.h>
#endif

#ifdef HAVE_PTHREAD_H
/* don't re-include config.h; on Windows, don't redefine pid_t in an
   incompatible way 
 */
#undef HAVE_CONFIG_H
#ifdef pid_t
#undef pid_t
#endif
#include <sched.h>
#include <pthread.h>
#ifndef WIN32
/* Linux gprof messes up on multithreaded programs */
#ifdef PROFILE
#define pthread_create gprof_pthread_create
#endif
#endif
#endif

#ifdef HAVE_SEMAPHORE_H
# include <semaphore.h>
#endif

/* new pthread interface, where the thread id changed to a struct */
#ifdef PTW32_VERSION
#define PTW32 1
#endif

#if !(defined(HAVE_SYSCONF) && defined(_SC_PHYS_PAGES)) && defined(HAVE_GETRLIMIT) && defined(HAVE_SYS_RESOURCE_H)
# include <sys/resource.h>
#endif

/* debug and errno integers */
gdk_export int GDKdebug;
#define MT_geterrno()	errno
#define MT_seterrno(x)	errno=x

#define MT_log(_impl, _object, _action, _caller, _fp) do { if (GDKdebug & 1024) { fprintf(_fp, "%s: " _action "(" PTRFMT ")\n", _caller, PTRFMTCAST(void*) _object); fflush(_fp); } _impl; } while (0)

/* virtual memory defines */
gdk_export size_t _MT_npages;
gdk_export size_t _MT_pagesize;
#define MT_pagesize()	_MT_pagesize
#define MT_npages()	_MT_npages


/* API */
gdk_export void    MT_init(void);     /*  init the package. */
gdk_export int     MT_alive(int pid); /* OS independent way to check if some process is still alive. */

#define MT_initialized() (MT_pagesize() > 0)



typedef size_t MT_Id; /* thread number. will not be zero*/

gdk_export int     MT_create_thread(MT_Id *t, void (*function) (void *), void *arg);
gdk_export void    MT_exit_thread(int status);
gdk_export void    MT_global_exit(int status);
gdk_export MT_Id   MT_getpid(void);
gdk_export int     MT_kill_thread(MT_Id t);
#ifdef HAVE_PTHREAD_SIGMASK
gdk_export void    MT_thread_sigmask(sigset_t * new_mask, sigset_t * orig_mask);
#endif

#if SIZEOF_VOID_P == 4
/* "limited" stack size on 32-bit systems */
/* to avoid address space fragmentation   */
#define THREAD_STACK_SIZE	((size_t)2*512*1024)
#else
/* "increased" stack size on 64-bit systems    */
/* since some compilers seem to require this   */
/* for burg-generated code in pathfinder       */
/* and address space fragmentation is no issue */
#define THREAD_STACK_SIZE	((size_t)4*512*1024)
#endif




typedef pthread_mutex_t MT_Lock;

#define MT_lock_init(l)      pthread_mutex_init((pthread_mutex_t*) l, 0)
#define MT_lock_destroy(l)   pthread_mutex_destroy((pthread_mutex_t*) l)
#define MT_lock_set(l,n)     MT_log(pthread_mutex_lock((pthread_mutex_t *) l), l, "MT_set_lock", n, stderr)
#define MT_lock_unset(l,n)   MT_log(pthread_mutex_unlock((pthread_mutex_t *) l), l, "MT_unset_lock", n, stderr)
#define MT_lock_try(l)       pthread_mutex_trylock((pthread_mutex_t *) l)
#define MT_lock_dump(l,fp,n) MT_log(/*nothing*/, &l, "MT_dump_lock", n, fp)

/* backward compatability API */
#define MT_init_lock(l)      MT_lock_init(&l)   
#define MT_destroy_lock(l)   MT_lock_destroy(&l)   
#define MT_set_lock(l,n)     MT_lock_set(&l,n)     
#define MT_unset_lock(l,n)   MT_lock_unset(&l,n)   
#define MT_try_lock(l)       MT_lock_try(&l)       
#define MT_dump_lock(l,fp,n) MT_lock_dump(&l,fp,n) 

gdk_export MT_Lock MT_system_lock;



#if defined(_AIX) || defined(__APPLE_CC__)
typedef struct {
	int cnt;
	pthread_mutex_t mutex;
	pthread_cond_t cond;
} pthread_sema_t;

gdk_export void    pthread_sema_init(pthread_sema_t *s, int flag, int nresources);
gdk_export void    pthread_sema_destroy(pthread_sema_t *s);
gdk_export void    pthread_sema_up(pthread_sema_t *s);
gdk_export void    pthread_sema_down(pthread_sema_t *s);
#else
#define pthread_sema_t       sem_t
#define pthread_sema_init    sem_init
#define pthread_sema_destroy sem_destroy
#define pthread_sema_up      sem_post
#define pthread_sema_down(x) while(sem_wait(x)) 
#endif

typedef pthread_sema_t MT_Sema;

#define MT_sema_init(s,nr)   pthread_sema_init(s,0,nr)
#define MT_sema_destroy(s)   pthread_sema_destroy(s)
#define MT_sema_up(s,n)      MT_log(pthread_sema_up(s), s, "MT_up_sema", n, stderr)
#define MT_sema_down(s,n)    MT_log(pthread_sema_down(s), s, "MT_down_sema", n, stderr)
#define MT_sema_dump(s,fp,n) MT_log(/*nothing*/, s, "MT_dump_sema", n, fp)

/* backward compatability API */
#define MT_init_sema(s,nr)   MT_sema_init(&s,nr)
#define MT_destroy_sema(s)   MT_sema_destroy(&s)
#define MT_up_sema(s,n)      MT_sema_up(&s,n)
#define MT_down_sema(s,n)    MT_sema_down(&s,n)
#define MT_dump_sema(s,fp,n) MT_sema_dump(&s,fp,n)



typedef pthread_cond_t MT_Cond;

#define MT_cond_init(c)      pthread_cond_init((pthread_cond_t*) c, NULL)
#define MT_cond_destroy(c)   pthread_cond_destroy((pthread_cond_t*) c)
#define MT_cond_signal(c,n)  MT_log(pthread_cond_signal((pthread_cond_t*) c), c, "MT_signal_cond", n, stderr)
#define MT_cond_wait(c,l,n)  MT_log(pthread_cond_wait((pthread_cond_t*) c, (pthread_mutex_t *) l), c, "MT_wait_cond", n, stderr)

/* backward compatability API */
#define MT_init_cond(c)      MT_cond_init(&c)
#define MT_destroy_cond(c)   MT_cond_destroy(&c)   
#define MT_signal_cond(c,n)  MT_cond_signal(&c,n)  
#define MT_wait_cond(c,l,n)  MT_cond_wait(&c,&l,n)  

#endif /*_GDK_SYSTEM_H_*/