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author | Rich Felker <dalias@aerifal.cx> | 2014-05-27 00:44:23 -0400 |
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committer | Rich Felker <dalias@aerifal.cx> | 2014-05-27 00:44:23 -0400 |
commit | 2fe6579125fe042f2255afbf00fc8e4b80d6a6be (patch) | |
tree | 153294950c138c8cbef7ca3a9dd145f99f7afc6e /src/stdio/tempnam.c | |
parent | 9b880a6b4112b0b3c0bd07949f7836daeea4e712 (diff) | |
download | musl-2fe6579125fe042f2255afbf00fc8e4b80d6a6be.tar.gz |
overhaul tmpfile, tmpnam, and tempnam functions
these all now use the shared __randname function internally, rather
than duplicating logic for producing a random name. incorrect usage of
the access syscall (which works with real uid/gid, not effective) has
been removed, along with unnecessary heavy dependencies like snprintf.
Diffstat (limited to 'src/stdio/tempnam.c')
-rw-r--r-- | src/stdio/tempnam.c | 55 |
1 files changed, 28 insertions, 27 deletions
diff --git a/src/stdio/tempnam.c b/src/stdio/tempnam.c index f73ca9f9..9bf8c727 100644 --- a/src/stdio/tempnam.c +++ b/src/stdio/tempnam.c @@ -1,42 +1,43 @@ #include <stdio.h> +#include <fcntl.h> +#include <errno.h> +#include <sys/stat.h> +#include <limits.h> #include <string.h> -#include <stdlib.h> -#include <stdint.h> -#include <unistd.h> -#include <time.h> -#include "libc.h" -#include "atomic.h" +#include "syscall.h" #define MAXTRIES 100 +char *__randname(char *); + 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; - - l = strlen(dir) + 1 + strlen(pfx) + 3*(sizeof(int)*3+2) + 1; - s = malloc(l); - if (!s) return s; + dl = strlen(dir); + pl = strlen(pfx); + l = dl + 1 + pl + 1 + 6; - do { - clock_gettime(CLOCK_REALTIME, &ts); - n = ts.tv_nsec ^ (uintptr_t)&s ^ (uintptr_t)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] = '_'; + + for (try=0; try<MAXTRIES; try++) { + __randname(s+l-6); + r = __syscall(SYS_lstat, s, &(struct stat){0}); + if (r == -ENOENT) return strdup(s); + } + return 0; } |