1#include <stdio.h>
2#include <fcntl.h>
3#include <errno.h>
4#include <sys/stat.h>
5#include <limits.h>
6#include <string.h>
7#include <stdlib.h>
8#include "syscall.h"
9
10#define MAXTRIES 100
11
12char *tempnam(const char *dir, const char *pfx)
13{
14 char s[PATH_MAX];
15 size_t l, dl, pl;
16 int try;
17 int r;
18
19 if (!dir) dir = P_tmpdir;
20 if (!pfx) pfx = "temp";
21
22 dl = strlen(dir);
23 pl = strlen(pfx);
24 l = dl + 1 + pl + 1 + 6;
25
26 if (l >= PATH_MAX) {
27 errno = ENAMETOOLONG;
28 return 0;
29 }
30
31 memcpy(s, dir, dl);
32 s[dl] = '/';
33 memcpy(s+dl+1, pfx, pl);
34 s[dl+1+pl] = '_';
35 s[l] = 0;
36
37 for (try=0; try<MAXTRIES; try++) {
38 __randname(s+l-6);
39#ifdef SYS_readlink
40 r = __syscall(SYS_readlink, s, (char[1]){0}, 1);
41#else
42 r = __syscall(SYS_readlinkat, AT_FDCWD, s, (char[1]){0}, 1);
43#endif
44 if (r == -ENOENT) return strdup(s);
45 }
46 return 0;
47}