posix/src/shmunlink.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  */
0006
0007 /*
0008  * Copyright (c) 2016 Gedare Bloom.
0009  *
0010  * Redistribution and use in source and binary forms, with or without
0011  * modification, are permitted provided that the following conditions
0012  * are met:
0013  * 1. Redistributions of source code must retain the above copyright
0014  *    notice, this list of conditions and the following disclaimer.
0015  * 2. Redistributions in binary form must reproduce the above copyright
0016  *    notice, this list of conditions and the following disclaimer in the
0017  *    documentation and/or other materials provided with the distribution.
0018  *
0019  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0020  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0021  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0022  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0023  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0024  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0025  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0026  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0027  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0028  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0029  * POSSIBILITY OF SUCH DAMAGE.
0030  */
0031
0032 #ifdef HAVE_CONFIG_H
0033 #include "config.h"
0034 #endif
0035
0036 #include <sys/mman.h>
0037 #include <errno.h>
0038 #include <rtems/seterr.h>
0039
0040 #include <rtems/posix/shmimpl.h>
0041
0042 int shm_unlink( const char *name )
0043 {
0044   Objects_Get_by_name_error obj_err;
0045   int err = 0;
0046   POSIX_Shm_Control *shm;
0047
0048   _Objects_Allocator_lock();
0049
0050   shm = _POSIX_Shm_Get_by_name( name, 0, &obj_err );
0051   if ( shm ) {
0052     _Objects_Namespace_remove_string(
0053       &_POSIX_Shm_Information,
0054       &shm->Object
0055     );
0056
0057     if ( shm->reference_count == 0 ) {
0058       /* Only remove the shm object if no references exist to it. Otherwise,
0059        * the shm object will be freed later in _POSIX_Shm_Attempt_delete */
0060       _POSIX_Shm_Free( shm );
0061     }
0062   } else {
0063     switch ( obj_err ) {
0064       case OBJECTS_GET_BY_NAME_NAME_TOO_LONG:
0065         err = ENAMETOOLONG;
0066         break;
0067
0068       case OBJECTS_GET_BY_NAME_INVALID_NAME:
0069       case OBJECTS_GET_BY_NAME_NO_OBJECT:
0070       default:
0071         err = ENOENT;
0072         break;
0073     }
0074   }
0075
0076   _Objects_Allocator_unlock();
0077
0078   if ( err != 0 )
0079     rtems_set_errno_and_return_minus_one( err );
0080   return 0;
0081 }