diff options
Diffstat (limited to 'mysys/thr_mutex.c')
| -rw-r--r-- | mysys/thr_mutex.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/mysys/thr_mutex.c b/mysys/thr_mutex.c new file mode 100644 index 00000000000..7eea5be473b --- /dev/null +++ b/mysys/thr_mutex.c @@ -0,0 +1,214 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, + MA 02111-1307, USA */ + +/* This makes a wrapper for mutex handling to make it easier to debug mutex */ + +#include <global.h> +#if defined(HAVE_LINUXTHREADS) && !defined (__USE_UNIX98) +#define __USE_UNIX98 /* To get rw locks under Linux */ +#endif +#include <m_string.h> +#if defined(THREAD) && defined(SAFE_MUTEX) +#undef SAFE_MUTEX /* Avoid safe_mutex redefinitions */ +#include <my_pthread.h> + +#ifndef DO_NOT_REMOVE_THREAD_WRAPPERS +/* Remove wrappers */ +#undef pthread_mutex_init +#undef pthread_mutex_lock +#undef pthread_mutex_unlock +#undef pthread_mutex_destroy +#undef pthread_cond_wait +#undef pthread_cond_timedwait +#ifdef HAVE_NONPOSIX_PTHREAD_MUTEX_INIT +#define pthread_mutex_init(a,b) my_pthread_mutex_init((a),(b)) +#endif +#endif + +int safe_mutex_init(safe_mutex_t *mp, + const pthread_mutexattr_t *attr __attribute__((unused))) +{ + bzero((char*) mp,sizeof(*mp)); +#ifdef HAVE_LINUXTHREADS /* Some extra safety */ + { + pthread_mutexattr_t tmp; + pthread_mutexattr_init(&tmp); + pthread_mutexattr_setkind_np(&tmp,PTHREAD_MUTEX_ERRORCHECK_NP); + pthread_mutex_init(&mp->global,&tmp); + pthread_mutex_init(&mp->mutex, &tmp); + pthread_mutexattr_destroy(&tmp); + } +#else + pthread_mutex_init(&mp->global,NULL); + pthread_mutex_init(&mp->mutex,attr); +#endif + return 0; +} + +int safe_mutex_lock(safe_mutex_t *mp,const char *file, uint line) +{ + int error; + pthread_mutex_lock(&mp->global); + if (mp->count > 0 && pthread_equal(pthread_self(),mp->thread)) + { + fprintf(stderr,"safe_mutex: Trying to lock mutex at %s, line %d, when the mutex was already locked at %s, line %d\n", + file,line,mp->file,mp->line); + abort(); + } + pthread_mutex_unlock(&mp->global); + error=pthread_mutex_lock(&mp->mutex); + if (error || (error=pthread_mutex_lock(&mp->global))) + { + fprintf(stderr,"Got error %d when trying to lock mutex at %s, line %d\n", + error, file, line); + abort(); + } + if (mp->count++) + { + fprintf(stderr,"safe_mutex: Error in thread libray: Got mutex at %s, line %d more than 1 time\n", file,line); + abort(); + } + mp->thread=pthread_self(); + mp->file= (char*) file; + mp->line=line; + pthread_mutex_unlock(&mp->global); + return error; +} + + +int safe_mutex_unlock(safe_mutex_t *mp,const char *file, uint line) +{ + int error; + pthread_mutex_lock(&mp->global); + if (mp->count == 0) + { + fprintf(stderr,"safe_mutex: Trying to unlock mutex that wasn't locked at %s, line %d\n Last used at %s, line: %d\n", + file,line,mp->file ? mp->file : "",mp->line); + abort(); + } + if (!pthread_equal(pthread_self(),mp->thread)) + { + fprintf(stderr,"safe_mutex: Trying to unlock mutex at %s, line %d that was locked by another thread at: %s, line: %d\n", + file,line,mp->file,mp->line); + abort(); + } + mp->count--; + error=pthread_mutex_unlock(&mp->mutex); + if (error) + { + fprintf(stderr,"safe_mutex: Got error: %d when trying to unlock mutex at %s, line %d\n", error, file, line); + abort(); + } + pthread_mutex_unlock(&mp->global); + return error; +} + + +int safe_cond_wait(pthread_cond_t *cond, safe_mutex_t *mp, const char *file, + uint line) +{ + int error; + pthread_mutex_lock(&mp->global); + if (mp->count == 0) + { + fprintf(stderr,"safe_mutex: Trying to cond_wait on a unlocked mutex at %s, line %d\n",file,line); + abort(); + } + if (!pthread_equal(pthread_self(),mp->thread)) + { + fprintf(stderr,"safe_mutex: Trying to cond_wait on a mutex at %s, line %d that was locked by another thread at: %s, line: %d\n", + file,line,mp->file,mp->line); + abort(); + } + + if (mp->count-- != 1) + { + fprintf(stderr,"safe_mutex: Count was %d on locked mutex at %s, line %d\n", + mp->count+1, file, line); + abort(); + } + pthread_mutex_unlock(&mp->global); + error=pthread_cond_wait(cond,&mp->mutex); + pthread_mutex_lock(&mp->global); + if (error) + { + fprintf(stderr,"safe_mutex: Got error: %d when doing a safe_mutex_wait at %s, line %d\n", error, file, line); + abort(); + } + if (mp->count++) + { + fprintf(stderr, + "safe_mutex: Count was %d in thread %lx when locking mutex at %s, line %d\n", + mp->count-1, my_thread_id(), file, line); + abort(); + } + mp->thread=pthread_self(); + mp->file= (char*) file; + mp->line=line; + pthread_mutex_unlock(&mp->global); + return error; +} + + +int safe_cond_timedwait(pthread_cond_t *cond, safe_mutex_t *mp, + struct timespec *abstime, + const char *file, uint line) +{ + int error; + pthread_mutex_lock(&mp->global); + if (mp->count != 1 || !pthread_equal(pthread_self(),mp->thread)) + { + fprintf(stderr,"safe_mutex: Trying to cond_wait at %s, line %d on a not hold mutex\n",file,line); + abort(); + } + mp->count--; /* Mutex will be released */ + pthread_mutex_unlock(&mp->global); + error=pthread_cond_timedwait(cond,&mp->mutex,abstime); +#ifdef EXTRA_DEBUG + if (error && (error != EINTR && error != ETIMEDOUT)) + { + fprintf(stderr,"safe_mutex: Got error: %d when doing a safe_mutex_timedwait at %s, line %d\n", error, file, line); + } +#endif + pthread_mutex_lock(&mp->global); + if (mp->count++) + { + fprintf(stderr, + "safe_mutex: Count was %d in thread %lx when locking mutex at %s, line %d (error: %d)\n", + mp->count-1, my_thread_id(), file, line, error); + abort(); + } + mp->thread=pthread_self(); + mp->file= (char*) file; + mp->line=line; + pthread_mutex_unlock(&mp->global); + return error; +} + +int safe_mutex_destroy(safe_mutex_t *mp, const char *file, uint line) +{ + if (mp->count != 0) + { + fprintf(stderr,"safe_mutex: Trying to destroy a mutex that was locked at %s, line %d at %s, line %d\n", + mp->file,mp->line, file, line); + abort(); + } + pthread_mutex_destroy(&mp->global); + return pthread_mutex_destroy(&mp->mutex); +} + +#endif /* SAFE_MUTEX */ |