1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <unistd.h>
5 
6 #define nil ((void*)0)
7 
8 char*
9 mkfname(char *tmpdir, char *prefix)
10 {
11 	int n;
12 	char *p, *fname;
13 
14 	if((p = getenv("TMPDIR")) != nil)
15 		goto Mktemp;
16 	if((p = tmpdir) != nil)
17 		goto Mktemp;
18 	p = "/tmp";
19 
20  Mktemp:
21 	n = strlen(p)+1+strlen(prefix)+1+8+1;
22 	if((fname = malloc(n)) == nil)
23 		return nil;
24 	memset(fname, 0, n);
25 	strcat(fname, p);
26 	if((n = strlen(p)) > 0 && p[n-1] != '/')
27 		strcat(fname, "/");
28 	strcat(fname, prefix);
29 	strcat(fname, ".XXXXXXXX");
30 
31 	return fname;
32 }
33 
34 extern	int	mkstemp(char*);
35 
36 char*
37 safe_tempnam(char *tmpdir, char *prefix)
38 {
39 	int fd;
40 	char *fname;
41 
42 	if((fname = mkfname(tmpdir, prefix)) == nil)
43 		return nil;
44 
45 	if((fd = mkstemp(fname)) < 0){		/* XXX: leak fd, fname */
46 		free(fname);
47 		return nil;
48 	}
49 	return fname;
50 }
51 
52 int
53 safe_tmpnam(char *fname)
54 {
55 	char *p;
56 
57 	if((p = mkfname(nil, "tmpfile")) == nil)
58 		return -1;
59 	strcpy(fname, p);
60 	free(p);
61 	return mkstemp(fname);
62 }