Commit 8fa3c789 authored by monty@hundin.mysql.fi's avatar monty@hundin.mysql.fi
Browse files

Added support for semaphores in mysys. 

(Needed for query cache for systems which doesn't have native semaphores)
parent 578a9d99

configure.in

+1 −1
Original line number Diff line number Diff line
@@ -1530,7 +1530,7 @@ AC_SUBST(MAKE_SHELL) 
AC_CHECK_HEADERS(varargs.h stdarg.h dirent.h locale.h ndir.h sys/dir.h \

 sys/file.h sys/ndir.h sys/ptem.h sys/pte.h sys/select.h sys/stream.h \

 sys/mman.h curses.h termcap.h termio.h termbits.h asm/termbits.h grp.h \

paths.h)

paths.h semaphore.h)



# Already-done: strcasecmp

AC_CHECK_FUNCS(lstat putenv select setenv setlocale strcoll tcgetattr)

include/my_semaphore.h

+13 −4
Original line number Diff line number Diff line
@@ -33,20 +33,29 @@ 


C_MODE_START



#ifndef __WIN__

#ifdef HAVE_SEMAPHORE_H

#include <semaphore.h>

#else



#ifdef __WIN__

typedef HANDLE sem_t;

#else

typedef struct {

  pthread_mutex_t mutex;

  pthread_cond_t  cond;

  uint            count;

} sem_t;

#endif



int sem_init(sem_t * sem, int pshared, unsigned int value);

int sem_destroy(sem_t * sem);

int sem_trywait(sem_t * sem);

int sem_wait(sem_t * sem);

int sem_post(sem_t * sem);

int sem_post_multiple(sem_t * sem,int count);

int sem_getvalue(sem_t * sem, int * sval);

int sem_post_multiple(sem_t * sem, unsigned int count);

int sem_getvalue(sem_t * sem, unsigned int * sval);



#endif /* __WIN__ */

#endif



C_MODE_END

#endif /* !_my_semaphore_h_ */

mysys/Makefile.am

+1 −1
Original line number Diff line number Diff line
@@ -46,7 +46,7 @@ libmysys_a_SOURCES = my_init.c my_getwd.c mf_getdate.c\ 
			my_quick.c my_lockmem.c my_static.c \

			my_getopt.c my_mkdir.c \

			default.c my_compress.c checksum.c raid.cc \

			my_net.c \

			my_net.c my_semaphore.c \

			my_vsnprintf.c charset.c my_bitmap.c my_bit.c md5.c \

			my_gethostbyname.c rijndael.c my_aes.c sha1.c

EXTRA_DIST =		thr_alarm.c thr_lock.c my_pthread.c my_thr_init.c \

mysys/my_getopt.c

+2 −2
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ int handle_options(int *argc, char ***argv, 
  uint opt_found, argvpos= 0, length, i;

  my_bool end_of_options= 0, must_be_var, set_maximum_value, special_used,

          option_is_loose;

  char *progname= *(*argv), **pos, *optend, *prev_found;

  char *progname= *(*argv), **pos, **pos_end, *optend, *prev_found;

  const struct my_option *optp;

  int error;
@@ -84,7 +84,7 @@ int handle_options(int *argc, char ***argv, 
  (*argv)++; /*      --- || ----      */

  init_variables(longopts);



  for (pos= *argv; *pos; pos++)

  for (pos= *argv, pos_end=pos+ *argc; pos != pos_end ; pos++)

  {

    char *cur_arg= *pos;

    if (cur_arg[0] == '-' && cur_arg[1] && !end_of_options) /* must be opt */

mysys/my_semaphore.c

0 → 100644
+103 −0
Original line number Diff line number Diff line 
/* Copyright (C) 2002 MySQL AB & MySQL Finland AB & TCX DataKonsult AB



 This program is free software; you can redistribute it and/or modify

 it under the terms of the GNU General Public License as published by

 the Free Software Foundation; either version 2 of the License, or

 (at your option) any later version.



 This program is distributed in the hope that it will be useful,

 but WITHOUT ANY WARRANTY; without even the implied warranty of

 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 GNU General Public License for more details.



 You should have received a copy of the GNU General Public License

 along with this program; if not, write to the Free Software

 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */



/*

  Simple implementation of semaphores, needed to compile MySQL on systems

  that doesn't support semaphores.

*/



#include <my_global.h>

#include <my_semaphore.h>



#if !defined(__WIN__) && !defined(HAVE_SEMAPHORE_H)



int sem_init(sem_t * sem, int pshared, uint value)

{

  sem->count=value;

  pthread_cond_init(&sem->cond, 0);

  pthread_mutex_init(&sem->mutex, 0);

  return 0;

}



int sem_destroy(sem_t * sem)

{

  int err1,err2;

  err1=pthread_cond_destroy(&sem->cond);

  err2=pthread_mutex_destroy(&sem->mutex);

  if (err1 || err2)

  {

    errno=err1 ? err1 : err2;

    return -1;

  }

  return 0;

}



int sem_wait(sem_t * sem)

{

  if ((errno=pthread_mutex_lock(&sem->mutex)))

    return -1;

  while (!sem->count)

    pthread_cond_wait(&sem->cond, &sem->mutex);

  if (errno)

    return -1;

  sem->count--; /* mutex is locked here */

  pthread_mutex_unlock(&sem->mutex);

  return 0;

}



int sem_trywait(sem_t * sem)

{

  if ((errno=pthread_mutex_lock(&sem->mutex)))

    return -1;

  if (sem->count)

    sem->count--;

  else

    errno=EAGAIN;

  pthread_mutex_unlock(&sem->mutex);

  return errno ? -1 : 0;

}





int sem_post(sem_t * sem)

{

  if ((errno=pthread_mutex_lock(&sem->mutex)))

    return -1;

  sem->count++;

  pthread_mutex_unlock(&sem->mutex);    /* does it really matter what to do */

  pthread_cond_signal(&sem->cond);      /* first: x_unlock or x_signal ?    */

  return 0;

}



int sem_post_multiple(sem_t * sem, uint count)

{

  if ((errno=pthread_mutex_lock(&sem->mutex)))

    return -1;

  sem->count+=count;

  pthread_mutex_unlock(&sem->mutex);    /* does it really matter what to do */

  pthread_cond_broadcast(&sem->cond);   /* first: x_unlock or x_broadcast ? */

  return 0;

}



int sem_getvalue(sem_t * sem, uint *sval)

{

  if ((errno=pthread_mutex_lock(&sem->mutex)))

    return -1;

  *sval=sem->count;

  pthread_mutex_unlock(&sem->mutex);

  return 0;

}



#endif /* !defined(__WIN__) && !defined(HAVE_SEMAPHORE_H) */