#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <limits.h>
#include <string.h>
#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
-#include "libc.h"
-#include "atomic.h"
+#include "syscall.h"
+#include "kstat.h"
#define MAXTRIES 100
char *tempnam(const char *dir, const char *pfx)
{
- static int index;
- char *s;
- struct timespec ts;
- int pid = getpid();
- size_t l;
- int n;
- int try=0;
+ char s[PATH_MAX];
+ size_t l, dl, pl;
+ int try;
+ int r;
if (!dir) dir = P_tmpdir;
if (!pfx) pfx = "temp";
- if (access(dir, R_OK|W_OK|X_OK) != 0)
- return NULL;
+ dl = strlen(dir);
+ pl = strlen(pfx);
+ l = dl + 1 + pl + 1 + 6;
- l = strlen(dir) + 1 + strlen(pfx) + 3*(sizeof(int)*3+2) + 1;
- s = malloc(l);
- if (!s) return s;
-
- do {
- clock_gettime(CLOCK_REALTIME, &ts);
- n = ts.tv_nsec ^ (unsigned)&s ^ (unsigned)s;
- snprintf(s, l, "%s/%s-%d-%d-%x", dir, pfx, pid, a_fetch_add(&index, 1), n);
- } while (!access(s, F_OK) && try++<MAXTRIES);
- if (try>=MAXTRIES) {
- free(s);
+ if (l >= PATH_MAX) {
+ errno = ENAMETOOLONG;
return 0;
}
- return s;
+
+ memcpy(s, dir, dl);
+ s[dl] = '/';
+ memcpy(s+dl+1, pfx, pl);
+ s[dl+1+pl] = '_';
+ s[l] = 0;
+
+ for (try=0; try<MAXTRIES; try++) {
+ __randname(s+l-6);
+#ifdef SYS_lstat
+ r = __syscall(SYS_lstat, s, &(struct kstat){0});
+#else
+ r = __syscall(SYS_fstatat, AT_FDCWD, s,
+ &(struct kstat){0}, AT_SYMLINK_NOFOLLOW);
+#endif
+ if (r == -ENOENT) return strdup(s);
+ }
+ return 0;
}