usr/src/lib/libc/port/gen/mkstemp.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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /* Copyright (c) 2013 OmniTI Computer Consulting, Inc. All rights reserved. */
  23
  24 /*
  25  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28
  29 /*
  30  * Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
  31  * All Rights Reserved
  32  *
  33  * Portions of this source code were derived from Berkeley
  34  * 4.3 BSD under license from the regents of the University of
  35  * California.
  36  */
  37
  38 #include <sys/feature_tests.h>
  39
  40 #if !defined(_LP64) && _FILE_OFFSET_BITS == 64
  41 #define mkstemp         mkstemp64
  42 #define mkstemps        mkstemps64
  43 #define mkostemp        mkostemp64
  44 #define mkostemps       mkostemps64
  45 #define libc_mkstemps   libc_mkstemps64         /* prefer unique statics */
  46 #pragma weak _mkstemp64 = mkstemp64
  47 #else
  48 #pragma weak _mkstemp = mkstemp
  49 #endif
  50
  51 #include "lint.h"
  52 #include <sys/fcntl.h>
  53 #include <stdlib.h>
  54 #include <string.h>
  55 #include <errno.h>
  56 #include <alloca.h>
  57 #include <sys/types.h>
  58 #include <sys/stat.h>
  59 #include <fcntl.h>
  60
  61 extern char *libc_mktemps(char *, int);
  62
  63 static int
  64 libc_mkstemps(char *as, int slen, int flags)
  65 {
  66         int     fd;
  67         int     len;
  68         char    *tstr, *str, *mkret;
  69
  70         if (as == NULL || *as == NULL)
  71                 return (-1);
  72
  73         len = (int)strlen(as);
  74         tstr = alloca(len + 1);
  75         (void) strcpy(tstr, as);
  76
  77         if (slen < 0 || slen >= len)
  78                 return (-1);
  79
  80         str = tstr + (len - 1 - slen);
  81
  82         /*
  83          * The following for() loop is doing work.  mktemp() will generate
  84          * a different name each time through the loop.  So if the first
  85          * name is used then keep trying until you find a free filename.
  86          */
  87
  88         for (;;) {
  89                 if (*str == 'X') { /* If no trailing X's don't call mktemp. */
  90                         mkret = libc_mktemps(as, slen);
  91                         if (*mkret == '\0') {
  92                                 return (-1);
  93                         }
  94                 }
  95 #if _FILE_OFFSET_BITS == 64
  96                 if ((fd = open64(as, O_CREAT|O_EXCL|O_RDWR|flags,
  97                     0600)) != -1) {
  98                         return (fd);
  99                 }
 100 #else
 101                 if ((fd = open(as, O_CREAT|O_EXCL|O_RDWR|flags,
 102                     0600)) != -1) {
 103                         return (fd);
 104                 }
 105 #endif  /* _FILE_OFFSET_BITS == 64 */
 106
 107                 /*
 108                  * If the error condition is other than EEXIST or if the
 109                  * file exists and there are no X's in the string
 110                  * return -1.
 111                  */
 112
 113                 if ((errno != EEXIST) || (*str != 'X')) {
 114                         return (-1);
 115                 }
 116                 (void) strcpy(as, tstr);
 117         }
 118 }
 119
 120 int
 121 mkstemp(char *as)
 122 {
 123         return (libc_mkstemps(as, 0, 0));
 124 }
 125
 126 int
 127 mkstemps(char *as, int slen)
 128 {
 129         return (libc_mkstemps(as, slen, 0));
 130 }
 131
 132 int
 133 mkostemp(char *as, int flags)
 134 {
 135         return (libc_mkstemps(as, 0, flags));
 136 }
 137
 138 int
 139 mkostemps(char *as, int slen, int flags)
 140 {
 141         return (libc_mkstemps(as, slen, flags));
 142 }