lib/libspl/getexecname.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or https://opensource.org/licenses/CDDL-1.0.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27
  28 #include <limits.h>
  29 #include <pthread.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <unistd.h>
  33 #include "libspl_impl.h"
  34
  35
  36 const char *
  37 getexecname(void)
  38 {
  39         static char execname[PATH_MAX + 1] = "";
  40         static pthread_mutex_t mtx = PTHREAD_MUTEX_INITIALIZER;
  41
  42         char *ptr = execname;
  43         ssize_t rc;
  44
  45         (void) pthread_mutex_lock(&mtx);
  46
  47         if (strlen(execname) == 0) {
  48                 rc = getexecname_impl(execname);
  49                 if (rc == -1) {
  50                         execname[0] = '\0';
  51                         ptr = NULL;
  52                 } else {
  53                         execname[rc] = '\0';
  54                 }
  55         }
  56
  57         (void) pthread_mutex_unlock(&mtx);
  58         return (ptr);
  59 }