diff options
author | rpj <rpj> | 2005-04-25 14:42:37 +0000 |
---|---|---|
committer | rpj <rpj> | 2005-04-25 14:42:37 +0000 |
commit | 3ef98898333255b8000e9ab4801652c42fd5aacc (patch) | |
tree | 58fbe722c2011a392ffb47ad56b97fe44e2fe59c /sem_init.c | |
parent | 75a3015fd7412637a02b1b016b367f5deadfde94 (diff) |
''
Diffstat (limited to 'sem_init.c')
-rw-r--r-- | sem_init.c | 328 |
1 files changed, 164 insertions, 164 deletions
@@ -1,164 +1,164 @@ -/*
- * -------------------------------------------------------------
- *
- * Module: sem_init.c
- *
- * Purpose:
- * Semaphores aren't actually part of PThreads.
- * They are defined by the POSIX Standard:
- *
- * POSIX 1003.1-2001
- *
- * -------------------------------------------------------------
- *
- * Pthreads-win32 - POSIX Threads Library for Win32
- * Copyright(C) 1998 John E. Bossom
- * Copyright(C) 1999,2005 Pthreads-win32 contributors
- *
- * Contact Email: rpj@callisto.canberra.edu.au
- *
- * The current list of contributors is contained
- * in the file CONTRIBUTORS included with the source
- * code distribution. The list can also be seen at the
- * following World Wide Web location:
- * http://sources.redhat.com/pthreads-win32/contributors.html
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library in the file COPYING.LIB;
- * if not, write to the Free Software Foundation, Inc.,
- * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
- */
-
-#include "pthread.h"
-#include "semaphore.h"
-#include "implement.h"
-
-int
-sem_init (sem_t * sem, int pshared, unsigned int value)
- /*
- * ------------------------------------------------------
- * DOCPUBLIC
- * This function initializes a semaphore. The
- * initial value of the semaphore is 'value'
- *
- * PARAMETERS
- * sem
- * pointer to an instance of sem_t
- *
- * pshared
- * if zero, this semaphore may only be shared between
- * threads in the same process.
- * if nonzero, the semaphore can be shared between
- * processes
- *
- * value
- * initial value of the semaphore counter
- *
- * DESCRIPTION
- * This function initializes a semaphore. The
- * initial value of the semaphore is set to 'value'.
- *
- * RESULTS
- * 0 successfully created semaphore,
- * -1 failed, error in errno
- * ERRNO
- * EINVAL 'sem' is not a valid semaphore,
- * ENOMEM out of memory,
- * ENOSPC a required resource has been exhausted,
- * ENOSYS semaphores are not supported,
- * EPERM the process lacks appropriate privilege
- *
- * ------------------------------------------------------
- */
-{
- int result = 0;
- sem_t s = NULL;
-
- if (pshared != 0)
- {
- /*
- * Creating a semaphore that can be shared between
- * processes
- */
- result = EPERM;
- }
- else
- {
- s = (sem_t) calloc (1, sizeof (*s));
-
- if (NULL == s)
- {
- result = ENOMEM;
- }
- else
- {
-
- s->value = value;
- if (pthread_mutex_init(&s->lock, NULL) == 0)
- {
-
-#ifdef NEED_SEM
-
- s->sem = CreateEvent (NULL,
- PTW32_FALSE, /* auto (not manual) reset */
- PTW32_FALSE, /* initial state is unset */
- NULL);
-
- if (0 == s->sem)
- {
- free (s);
- (void) pthread_mutex_destroy(&s->lock);
- result = ENOSPC;
- }
- else
- {
- s->leftToUnblock = 0;
- }
-
-#else /* NEED_SEM */
-
- if ((s->sem = CreateSemaphore (NULL, /* Always NULL */
- (long) 0, /* Force threads to wait */
- (long) _POSIX_SEM_VALUE_MAX, /* Maximum value */
- NULL)) == 0) /* Name */
- {
- (void) pthread_mutex_destroy(&s->lock);
- result = ENOSPC;
- }
-
-#endif /* NEED_SEM */
-
- }
- else
- {
- result = ENOSPC;
- }
-
- if (result != 0)
- {
- free(s);
- }
- }
- }
-
- if (result != 0)
- {
- errno = result;
- return -1;
- }
-
- *sem = s;
-
- return 0;
-
-} /* sem_init */
+/* + * ------------------------------------------------------------- + * + * Module: sem_init.c + * + * Purpose: + * Semaphores aren't actually part of PThreads. + * They are defined by the POSIX Standard: + * + * POSIX 1003.1-2001 + * + * ------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2005 Pthreads-win32 contributors + * + * Contact Email: rpj@callisto.canberra.edu.au + * + * The current list of contributors is contained + * in the file CONTRIBUTORS included with the source + * code distribution. The list can also be seen at the + * following World Wide Web location: + * http://sources.redhat.com/pthreads-win32/contributors.html + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library in the file COPYING.LIB; + * if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "pthread.h" +#include "semaphore.h" +#include "implement.h" + +int +sem_init (sem_t * sem, int pshared, unsigned int value) + /* + * ------------------------------------------------------ + * DOCPUBLIC + * This function initializes a semaphore. The + * initial value of the semaphore is 'value' + * + * PARAMETERS + * sem + * pointer to an instance of sem_t + * + * pshared + * if zero, this semaphore may only be shared between + * threads in the same process. + * if nonzero, the semaphore can be shared between + * processes + * + * value + * initial value of the semaphore counter + * + * DESCRIPTION + * This function initializes a semaphore. The + * initial value of the semaphore is set to 'value'. + * + * RESULTS + * 0 successfully created semaphore, + * -1 failed, error in errno + * ERRNO + * EINVAL 'sem' is not a valid semaphore, + * ENOMEM out of memory, + * ENOSPC a required resource has been exhausted, + * ENOSYS semaphores are not supported, + * EPERM the process lacks appropriate privilege + * + * ------------------------------------------------------ + */ +{ + int result = 0; + sem_t s = NULL; + + if (pshared != 0) + { + /* + * Creating a semaphore that can be shared between + * processes + */ + result = EPERM; + } + else + { + s = (sem_t) calloc (1, sizeof (*s)); + + if (NULL == s) + { + result = ENOMEM; + } + else + { + + s->value = value; + if (pthread_mutex_init(&s->lock, NULL) == 0) + { + +#ifdef NEED_SEM + + s->sem = CreateEvent (NULL, + PTW32_FALSE, /* auto (not manual) reset */ + PTW32_FALSE, /* initial state is unset */ + NULL); + + if (0 == s->sem) + { + free (s); + (void) pthread_mutex_destroy(&s->lock); + result = ENOSPC; + } + else + { + s->leftToUnblock = 0; + } + +#else /* NEED_SEM */ + + if ((s->sem = CreateSemaphore (NULL, /* Always NULL */ + (long) 0, /* Force threads to wait */ + (long) _POSIX_SEM_VALUE_MAX, /* Maximum value */ + NULL)) == 0) /* Name */ + { + (void) pthread_mutex_destroy(&s->lock); + result = ENOSPC; + } + +#endif /* NEED_SEM */ + + } + else + { + result = ENOSPC; + } + + if (result != 0) + { + free(s); + } + } + } + + if (result != 0) + { + errno = result; + return -1; + } + + *sem = s; + + return 0; + +} /* sem_init */ |