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-rw-r--r--src/stdio/tempnam.c39
1 files changed, 19 insertions, 20 deletions
diff --git a/src/stdio/tempnam.c b/src/stdio/tempnam.c
index 2cbcb864..dc4f2bad 100644
--- a/src/stdio/tempnam.c
+++ b/src/stdio/tempnam.c
@@ -1,19 +1,22 @@
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
-#include <fcntl.h>
#include <unistd.h>
-#include <limits.h>
-#include <errno.h>
+#include <time.h>
#include "libc.h"
+#include "atomic.h"
+
+#define MAXTRIES 100
char *tempnam(const char *dir, const char *pfx)
{
- static int lock;
static int index;
char *s;
+ struct timespec ts;
int pid = getpid();
- int l;
+ size_t l;
+ int n;
+ int try=0;
if (!dir) dir = P_tmpdir;
if (!pfx) pfx = "temp";
@@ -21,22 +24,18 @@ char *tempnam(const char *dir, const char *pfx)
if (access(dir, R_OK|W_OK|X_OK) != 0)
return NULL;
- l = strlen(dir) + 1 + strlen(pfx) + 2 + sizeof(int)*3*2 + 1;
+ l = strlen(dir) + 1 + strlen(pfx) + 3*(sizeof(int)*3+2) + 1;
s = malloc(l);
- if (!s) {
- errno = ENOMEM;
- return NULL;
- }
+ if (!s) return s;
- LOCK(&lock);
- for (; index < TMP_MAX; index++) {
- snprintf(s, l, "%s/%s-%d-%d", dir, pfx, pid, index);
- if (access(s, F_OK) != 0) {
- UNLOCK(&lock);
- 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);
+ return 0;
}
- UNLOCK(&lock);
- free(s);
- return NULL;
+ return s;
}