1 /* Copyright (C) 1999, 2001-2003 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If not,
16 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 Boston, MA 02111-1307, USA. */
19 /* Extracted from misc/mkdtemp.c and sysdeps/posix/tempname.c. */
30 # define __set_errno(Val) errno = (Val)
39 # define TMP_MAX 238328
42 #if HAVE_STDINT_H || _LIBC
46 # include <inttypes.h>
49 #if HAVE_UNISTD_H || _LIBC
53 #if HAVE_GETTIMEOFDAY || _LIBC
54 # if HAVE_SYS_TIME_H || _LIBC
55 # include <sys/time.h>
58 # if HAVE_TIME_H || _LIBC
64 #if STAT_MACROS_BROKEN
67 #if !defined S_ISDIR && defined S_IFDIR
68 # define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
70 #if !S_IRUSR && S_IREAD
71 # define S_IRUSR S_IREAD
74 # define S_IRUSR 00400
76 #if !S_IWUSR && S_IWRITE
77 # define S_IWUSR S_IWRITE
80 # define S_IWUSR 00200
82 #if !S_IXUSR && S_IEXEC
83 # define S_IXUSR S_IEXEC
86 # define S_IXUSR 00100
90 # define __getpid getpid
91 # define __gettimeofday gettimeofday
92 # define __mkdir mkdir
95 /* Use the widest available unsigned type if uint64_t is not
96 available. The algorithm below extracts a number less than 62**6
97 (approximately 2**35.725) from uint64_t, so ancient hosts where
98 uintmax_t is only 32 bits lose about 3.725 bits of randomness,
99 which is better than not having mkstemp at all. */
100 #if !defined UINT64_MAX && !defined uint64_t
101 # define uint64_t uintmax_t
104 /* These are the characters used in temporary filenames. */
105 static const char letters[] =
106 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
108 /* Generate a temporary file name based on TMPL. TMPL must match the
109 rules for mk[s]temp (i.e. end in "XXXXXX"). The name constructed
110 does not exist at the time of the call to __gen_tempname. TMPL is
111 overwritten with the result.
114 __GT_DIR: create a directory, which will be mode 0700.
116 We use a clever algorithm to get hard-to-predict names. */
118 gen_tempname (char *tmpl)
122 static uint64_t value;
123 uint64_t random_time_bits;
125 int save_errno = errno;
128 if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX"))
130 __set_errno (EINVAL);
134 /* This is where the Xs start. */
135 XXXXXX = &tmpl[len - 6];
137 /* Get some more or less random data. */
139 RANDOM_BITS (random_time_bits);
141 # if HAVE_GETTIMEOFDAY || _LIBC
144 __gettimeofday (&tv, NULL);
145 random_time_bits = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec;
148 random_time_bits = time (NULL);
151 value += random_time_bits ^ __getpid ();
153 for (count = 0; count < TMP_MAX; value += 7777, ++count)
157 /* Fill in the random bits. */
158 XXXXXX[0] = letters[v % 62];
160 XXXXXX[1] = letters[v % 62];
162 XXXXXX[2] = letters[v % 62];
164 XXXXXX[3] = letters[v % 62];
166 XXXXXX[4] = letters[v % 62];
168 XXXXXX[5] = letters[v % 62];
170 fd = __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR);
174 __set_errno (save_errno);
177 else if (errno != EEXIST)
181 /* We got out of the loop because we ran out of combinations to try. */
182 __set_errno (EEXIST);
186 /* Generate a unique temporary directory from TEMPLATE.
187 The last six characters of TEMPLATE must be "XXXXXX";
188 they are replaced with a string that makes the filename unique.
189 The directory is created, mode 700, and its name is returned.
190 (This function comes from OpenBSD.) */
192 mkdtemp (char *template)
194 if (gen_tempname (template))