-/* Copyright (C) 1991,92,93,94,95,96,97,98 Free Software Foundation, Inc.
+/* Copyright (C) 1991-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
- Library General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#if !_LIBC
+# include <config.h>
+# include "tempname.h"
+#endif
+
+#include <sys/types.h>
+#include <assert.h>
+
+#include <errno.h>
+#ifndef __set_errno
+# define __set_errno(Val) errno = (Val)
+#endif
-#include <stddef.h>
-#include <stdint.h>
#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_DIR 1
+# define __GT_NOCREATE 2
+#endif
+#if !_LIBC && (GT_FILE != __GT_FILE || GT_DIR != __GT_DIR \
+ || GT_NOCREATE != __GT_NOCREATE)
+# error report this to bug-gnulib@gnu.org
+#endif
+
+#include <stddef.h>
#include <stdlib.h>
#include <string.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
+
#include <fcntl.h>
-#include <unistd.h>
#include <sys/time.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#if _LIBC
+# define struct_stat64 struct stat64
+# define __secure_getenv __libc_secure_getenv
+#else
+# define struct_stat64 struct stat
+# define __gen_tempname gen_tempname
+# define __getpid getpid
+# define __gettimeofday gettimeofday
+# define __mkdir mkdir
+# define __open open
+# define __lxstat64(version, file, buf) lstat (file, buf)
+# define __secure_getenv secure_getenv
+#endif
+
+#ifdef _LIBC
+# include <hp-timing.h>
+# if HP_TIMING_AVAIL
+# define RANDOM_BITS(Var) \
+ if (__glibc_unlikely (value == UINT64_C (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
+
+#if _LIBC
/* Return nonzero if DIR is an existent directory. */
static int
direxists (const char *dir)
{
- struct stat buf;
- return __stat (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
+ 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
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)
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+ int try_tmpdir)
{
const char *d;
size_t dlen, plen;
plen = 5;
}
- d = __secure_getenv ("TMPDIR");
- if (d != NULL && direxists (d))
- dir = d;
- else if (dir != NULL && direxists (dir))
- /* nothing */ ;
- else if (direxists (P_tmpdir))
- dir = P_tmpdir;
- else if (direxists ("/tmp"))
- dir = "/tmp";
- else
+ if (try_tmpdir)
{
- __set_errno (ENOENT);
- return -1;
+ 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);
return -1;
}
- sprintf (tmpl, "%*s/%*sXXXXXX", dlen, dir, plen, pfx);
+ sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
return 0;
}
+#endif /* _LIBC */
-/* These are the characters used in temporary filenames. */
+/* 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. If OPENIT is nonzero, creates the
- file and returns a read-write fd; the file is mode 0600 modulo
- umask. If LARGEFILE is nonzero, uses open64() instead of open().
+ rules for mk[s]temp (i.e. end in "XXXXXX", possibly with a suffix).
+ 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_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 openit, int largefile)
+__gen_tempname (char *tmpl, int suffixlen, int flags, int kind)
{
int len;
char *XXXXXX;
static uint64_t value;
- struct timeval tv;
- int count, fd;
+ 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 of 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. */
+#define 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. */
+#if ATTEMPTS_MIN < TMP_MAX
+ unsigned int attempts = TMP_MAX;
+#else
+ unsigned int attempts = ATTEMPTS_MIN;
+#endif
len = strlen (tmpl);
- if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX"))
+ if (len < 6 + suffixlen || memcmp (&tmpl[len - 6 - suffixlen], "XXXXXX", 6))
{
__set_errno (EINVAL);
return -1;
}
/* This is where the Xs start. */
- XXXXXX = &tmpl[len - 6];
+ XXXXXX = &tmpl[len - 6 - suffixlen];
/* Get some more or less random data. */
- __gettimeofday (&tv, NULL);
- value += ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec ^ __getpid ();
+#ifdef RANDOM_BITS
+ RANDOM_BITS (random_time_bits);
+#else
+ {
+ struct timeval tv;
+ __gettimeofday (&tv, NULL);
+ random_time_bits = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec;
+ }
+#endif
+ value += random_time_bits ^ __getpid ();
- for (count = 0; count < TMP_MAX; value += 7777, ++count)
+ for (count = 0; count < attempts; value += 7777, ++count)
{
uint64_t v = value;
v /= 62;
XXXXXX[5] = letters[v % 62];
- if (openit)
+ switch (kind)
{
- fd = (largefile
- ? __open (tmpl, O_RDWR | O_CREAT | O_EXCL, 0666)
- : __open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, 0666));
- if (fd >= 0)
- {
- __set_errno (save_errno);
- return fd;
- }
- else if (errno != EEXIST)
- /* Any other error will apply also to other names we might
- try, and there are 2^32 or so of them, so give up now. */
- return -1;
- }
- else
- {
- struct stat st;
- if (__stat (tmpl, &st) < 0)
+ case __GT_FILE:
+ fd = __open (tmpl,
+ (flags & ~O_ACCMODE)
+ | 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)
{
/* Give up now. */
return -1;
}
+ continue;
+
+ default:
+ assert (! "invalid KIND in __gen_tempname");
+ abort ();
+ }
+
+ 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. */
projects / thirdparty / glibc.git / blobdiff