diff options
| -rw-r--r-- | lib/libc/stdio/mktemp.c | 37 |
1 files changed, 26 insertions, 11 deletions
diff --git a/lib/libc/stdio/mktemp.c b/lib/libc/stdio/mktemp.c index e8f51d4..3f1e699 100644 --- a/lib/libc/stdio/mktemp.c +++ b/lib/libc/stdio/mktemp.c @@ -34,7 +34,7 @@ static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93"; __FBSDID("$FreeBSD$"); #include "namespace.h" -#include <sys/types.h> +#include <sys/param.h> #include <sys/stat.h> #include <fcntl.h> #include <errno.h> @@ -102,13 +102,14 @@ _gettemp(path, doopen, domkdir, slen) int domkdir; int slen; { - char *start, *trv, *suffp; + char *start, *trv, *suffp, *carryp; char *pad; struct stat sbuf; int rval; uint32_t rand; + char carrybuf[MAXPATHLEN]; - if (doopen != NULL && domkdir) { + if ((doopen != NULL && domkdir) || slen < 0) { errno = EINVAL; return (0); } @@ -118,7 +119,7 @@ _gettemp(path, doopen, domkdir, slen) trv -= slen; suffp = trv; --trv; - if (trv < path) { + if (trv < path || NULL != strchr(suffp, '/')) { errno = EINVAL; return (0); } @@ -130,6 +131,9 @@ _gettemp(path, doopen, domkdir, slen) } start = trv + 1; + /* save first combination of random characters */ + memcpy(carrybuf, start, suffp - start); + /* * check the target directory. */ @@ -166,14 +170,25 @@ _gettemp(path, doopen, domkdir, slen) return (errno == ENOENT); /* If we have a collision, cycle through the space of filenames */ - for (trv = start;;) { - if (*trv == '\0' || trv == suffp) - return (0); + for (trv = start, carryp = carrybuf;;) { + /* have we tried all possible permutations? */ + if (trv == suffp) + return (0); /* yes - exit with EEXIST */ pad = strchr(padchar, *trv); - if (pad == NULL || *++pad == '\0') - *trv++ = padchar[0]; - else { - *trv++ = *pad; + if (pad == NULL) { + /* this should never happen */ + errno = EIO; + return (0); + } + /* increment character */ + *trv = (*++pad == '\0') ? padchar[0] : *pad; + /* carry to next position? */ + if (*trv == *carryp) { + /* increment position and loop */ + ++trv; + ++carryp; + } else { + /* try with new name */ break; } } |
