diff options
Diffstat (limited to 'lib/tempname.c')
| -rw-r--r-- | lib/tempname.c | 319 |
1 files changed, 0 insertions, 319 deletions
diff --git a/lib/tempname.c b/lib/tempname.c deleted file mode 100644 index a25beb205..000000000 --- a/lib/tempname.c +++ /dev/null @@ -1,319 +0,0 @@ -/* tempname.c - generate the name of a temporary file. - - Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, - 2000, 2001, 2002, 2003, 2005, 2006 Free Software Foundation, Inc. - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2, or (at your option) - any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License along - with this program; if not, write to the Free Software Foundation, - Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ - -#ifdef HAVE_CONFIG_H -# include <config.h> -#endif - -#include <sys/types.h> -#include <assert.h> - -#include <errno.h> -#ifndef __set_errno -# define __set_errno(Val) errno = (Val) -#endif - -#include <stdio.h> -#ifndef P_tmpdir -# define P_tmpdir "/tmp" -#endif -#ifndef TMP_MAX -# define TMP_MAX 238328 -#endif -#ifndef __GT_FILE -# define __GT_FILE 0 -# define __GT_BIGFILE 1 -# define __GT_DIR 2 -# define __GT_NOCREATE 3 -#endif - -#include <stddef.h> -#include <stdlib.h> -#include <string.h> - -#include <fcntl.h> - -#if HAVE_SYS_TIME_H || _LIBC -# include <sys/time.h> -#endif - -#if HAVE_STDINT_H || _LIBC -# include <stdint.h> -#endif -#if HAVE_INTTYPES_H -# include <inttypes.h> -#endif - -#include <unistd.h> - -#include <sys/stat.h> - -#if _LIBC -# define struct_stat64 struct stat64 -# define small_open __open -# define large_open __open64 -#else -# include "stat-macros.h" -# define struct_stat64 struct stat -# define small_open open -# define large_open open -# define __getpid getpid -# define __gettimeofday gettimeofday -# define __mkdir mkdir -# define __lxstat64(version, file, buf) lstat (file, buf) -# define __xstat64(version, file, buf) stat (file, buf) -#endif - -#if ! (HAVE___SECURE_GETENV || _LIBC) -# define __secure_getenv getenv -#endif - -#ifdef _LIBC -# include <hp-timing.h> -# if HP_TIMING_AVAIL -# define RANDOM_BITS(Var) \ - if (__builtin_expect (value == UINT64_C (0), 0)) \ - { \ - /* If this is the first time this function is used initialize \ - the variable we accumulate the value in to some somewhat \ - random value. If we'd not do this programs at startup time \ - might have a reduced set of possible names, at least on slow \ - machines. */ \ - struct timeval tv; \ - __gettimeofday (&tv, NULL); \ - value = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec; \ - } \ - HP_TIMING_NOW (Var) -# endif -#endif - -/* Use the widest available unsigned type if uint64_t is not - available. The algorithm below extracts a number less than 62**6 - (approximately 2**35.725) from uint64_t, so ancient hosts where - uintmax_t is only 32 bits lose about 3.725 bits of randomness, - which is better than not having mkstemp at all. */ -#if !defined UINT64_MAX && !defined uint64_t -# define uint64_t uintmax_t -#endif - -/* Return nonzero if DIR is an existent directory. */ -static int -direxists (const char *dir) -{ - struct_stat64 buf; - return __xstat64 (_STAT_VER, dir, &buf) == 0 && S_ISDIR (buf.st_mode); -} - -/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is - non-null and exists, uses it; otherwise uses the first of $TMPDIR, - P_tmpdir, /tmp that exists. Copies into TMPL a template suitable - for use with mk[s]temp. Will fail (-1) if DIR is non-null and - doesn't exist, none of the searched dirs exists, or there's not - enough space in TMPL. */ -int -__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx, - int try_tmpdir) -{ - const char *d; - size_t dlen, plen; - - if (!pfx || !pfx[0]) - { - pfx = "file"; - plen = 4; - } - else - { - plen = strlen (pfx); - if (plen > 5) - plen = 5; - } - - if (try_tmpdir) - { - d = __secure_getenv ("TMPDIR"); - if (d != NULL && direxists (d)) - dir = d; - else if (dir != NULL && direxists (dir)) - /* nothing */ ; - else - dir = NULL; - } - if (dir == NULL) - { - if (direxists (P_tmpdir)) - dir = P_tmpdir; - else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp")) - dir = "/tmp"; - else - { - __set_errno (ENOENT); - return -1; - } - } - - dlen = strlen (dir); - while (dlen > 1 && dir[dlen - 1] == '/') - dlen--; /* remove trailing slashes */ - - /* check we have room for "${dir}/${pfx}XXXXXX\0" */ - if (tmpl_len < dlen + 1 + plen + 6 + 1) - { - __set_errno (EINVAL); - return -1; - } - - sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx); - return 0; -} - -/* These are the characters used in temporary file names. */ -static const char letters[] = -"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; - -/* Generate a temporary file name based on TMPL. TMPL must match the - rules for mk[s]temp (i.e. end in "XXXXXX"). The name constructed - does not exist at the time of the call to __gen_tempname. TMPL is - overwritten with the result. - - KIND may be one of: - __GT_NOCREATE: simply verify that the name does not exist - at the time of the call. - __GT_FILE: create the file using open(O_CREAT|O_EXCL) - and return a read-write fd. The file is mode 0600. - __GT_BIGFILE: same as __GT_FILE but use open64(). - __GT_DIR: create a directory, which will be mode 0700. - - We use a clever algorithm to get hard-to-predict names. */ -int -__gen_tempname (char *tmpl, int kind) -{ - int len; - char *XXXXXX; - static uint64_t value; - uint64_t random_time_bits; - unsigned int count; - int fd = -1; - int save_errno = errno; - struct_stat64 st; - - /* A lower bound on the number of temporary files to attempt to - generate. The maximum total number of temporary file names that - can exist for a given template is 62**6. It should never be - necessary to try all these combinations. Instead if a reasonable - number of names is tried (we define reasonable as 62**3) fail to - give the system administrator the chance to remove the problems. */ - unsigned int attempts_min = 62 * 62 * 62; - - /* The number of times to attempt to generate a temporary file. To - conform to POSIX, this must be no smaller than TMP_MAX. */ - unsigned int attempts = attempts_min < TMP_MAX ? TMP_MAX : attempts_min; - - len = strlen (tmpl); - if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX")) - { - __set_errno (EINVAL); - return -1; - } - - /* This is where the Xs start. */ - XXXXXX = &tmpl[len - 6]; - - /* Get some more or less random data. */ -#ifdef RANDOM_BITS - RANDOM_BITS (random_time_bits); -#else -# if HAVE_GETTIMEOFDAY || _LIBC - { - struct timeval tv; - __gettimeofday (&tv, NULL); - random_time_bits = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec; - } -# else - random_time_bits = time (NULL); -# endif -#endif - value += random_time_bits ^ __getpid (); - - for (count = 0; count < attempts; value += 7777, ++count) - { - uint64_t v = value; - - /* Fill in the random bits. */ - XXXXXX[0] = letters[v % 62]; - v /= 62; - XXXXXX[1] = letters[v % 62]; - v /= 62; - XXXXXX[2] = letters[v % 62]; - v /= 62; - XXXXXX[3] = letters[v % 62]; - v /= 62; - XXXXXX[4] = letters[v % 62]; - v /= 62; - XXXXXX[5] = letters[v % 62]; - - switch (kind) - { - case __GT_FILE: - fd = small_open (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); - break; - - case __GT_BIGFILE: - fd = large_open (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); - break; - - case __GT_DIR: - fd = __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR); - break; - - case __GT_NOCREATE: - /* This case is backward from the other three. __gen_tempname - succeeds if __xstat fails because the name does not exist. - Note the continue to bypass the common logic at the bottom - of the loop. */ - if (__lxstat64 (_STAT_VER, tmpl, &st) < 0) - { - if (errno == ENOENT) - { - __set_errno (save_errno); - return 0; - } - else - /* Give up now. */ - return -1; - } - continue; - - default: - assert (! "invalid KIND in __gen_tempname"); - } - - if (fd >= 0) - { - __set_errno (save_errno); - return fd; - } - else if (errno != EEXIST) - return -1; - } - - /* We got out of the loop because we ran out of combinations to try. */ - __set_errno (EEXIST); - return -1; -} |