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author | Rich Felker <dalias@aerifal.cx> | 2011-03-29 08:34:47 -0400 |
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committer | Rich Felker <dalias@aerifal.cx> | 2011-03-29 08:34:47 -0400 |
commit | 507a9fa6ff9948eb7d858467b7be2cb1dcf15d03 (patch) | |
tree | 90d5e4f8977942072e5a418dbc7ea5bbc8cd72be /src/stdio | |
parent | 9646e4d024c05332c9653419abd6c41fdd48a33b (diff) | |
download | musl-507a9fa6ff9948eb7d858467b7be2cb1dcf15d03.tar.gz musl-507a9fa6ff9948eb7d858467b7be2cb1dcf15d03.tar.bz2 musl-507a9fa6ff9948eb7d858467b7be2cb1dcf15d03.tar.xz musl-507a9fa6ff9948eb7d858467b7be2cb1dcf15d03.zip |
fix tmpnam to generate better names, not depend on non-ISO-C symbols
Diffstat (limited to 'src/stdio')
-rw-r--r-- | src/stdio/tmpnam.c | 42 |
1 files changed, 17 insertions, 25 deletions
diff --git a/src/stdio/tmpnam.c b/src/stdio/tmpnam.c index 14d59220..6099b74b 100644 --- a/src/stdio/tmpnam.c +++ b/src/stdio/tmpnam.c @@ -1,38 +1,30 @@ #include <stdio.h> #include <stdlib.h> -#include <string.h> -#include <limits.h> #include <unistd.h> +#include <time.h> #include "libc.h" +#include "syscall.h" +#include "atomic.h" + +#define MAXTRIES 100 char *tmpnam(char *s) { - static int lock; static int index; - static char *s2; - int pid = getpid(); - char *dir = getenv("TMPDIR"); - - if (!s) { - if (!s2) s2 = malloc(L_tmpnam); - s = s2; - } + static char s2[L_tmpnam]; + struct timespec ts; + int try = 0; + unsigned n; - /* this interface is insecure anyway but at least we can try.. */ - if (!dir || strlen(dir) > L_tmpnam-32) - dir = P_tmpdir; + if (!s) s = s2; - if (access(dir, R_OK|W_OK|X_OK) != 0) + if (__syscall(SYS_access, P_tmpdir, R_OK|W_OK|X_OK) != 0) return NULL; - LOCK(&lock); - for (index++; index < TMP_MAX; index++) { - snprintf(s, L_tmpnam, "%s/temp%d-%d", dir, pid, index); - if (access(s, F_OK) != 0) { - UNLOCK(&lock); - return s; - } - } - UNLOCK(&lock); - return NULL; + do { + __syscall(SYS_clock_gettime, CLOCK_REALTIME, &ts, 0); + n = ts.tv_nsec ^ (unsigned)&s ^ (unsigned)s; + snprintf(s, L_tmpnam, "/tmp/t%x-%x", a_fetch_add(&index, 1), n); + } while (!__syscall(SYS_access, s, F_OK) && try++<MAXTRIES); + return try==MAXTRIES ? 0 : s; } |