xref: /freebsd/crypto/heimdal/lib/roken/mkstemp.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*
2  * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <config.h>
35 
36 #include <string.h>
37 #ifdef HAVE_UNISTD_H
38 #include <unistd.h>
39 #endif
40 #ifdef HAVE_FCNTL_H
41 #include <fcntl.h>
42 #endif
43 #include <errno.h>
44 
45 #include <roken.h>
46 
47 #ifndef HAVE_MKSTEMP
48 
49 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
50 mkstemp(char *template)
51 {
52     int start, i;
53     pid_t val;
54     val = getpid();
55     start = strlen(template) - 1;
56     while(template[start] == 'X') {
57 	template[start] = '0' + val % 10;
58 	val /= 10;
59 	start--;
60     }
61 
62     do{
63 	int fd;
64 	fd = open(template, O_RDWR | O_CREAT | O_EXCL, 0600);
65 	if(fd >= 0 || errno != EEXIST)
66 	    return fd;
67 	i = start + 1;
68 	do{
69 	    if(template[i] == 0)
70 		return -1;
71 	    template[i]++;
72 	    if(template[i] == '9' + 1)
73 		template[i] = 'a';
74 	    if(template[i] <= 'z')
75 		break;
76 	    template[i] = 'a';
77 	    i++;
78 	}while(1);
79     }while(1);
80 }
81 
82 #endif
83