1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147
|
/* Copyright (C) 1991, 1992, 1996, 1998, 2004 Free Software Foundation, Inc.
This file is derived from mkstemp.c from 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.
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.
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., 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA. */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include "ansidecl.h"
/* We need to provide a type for gcc_uint64_t. */
#ifdef __GNUC__
__extension__ typedef unsigned long long gcc_uint64_t;
#else
typedef unsigned long gcc_uint64_t;
#endif
#ifndef TMP_MAX
#define TMP_MAX 16384
#endif
#ifndef O_BINARY
# define O_BINARY 0
#endif
/*
@deftypefn Replacement int mkstemps (char *@var{pattern}, int @var{suffix_len})
Generate a unique temporary file name from @var{pattern}.
@var{pattern} has the form:
@example
@var{path}/ccXXXXXX@var{suffix}
@end example
@var{suffix_len} tells us how long @var{suffix} is (it can be zero
length). The last six characters of @var{pattern} before @var{suffix}
must be @samp{XXXXXX}; they are replaced with a string that makes the
filename unique. Returns a file descriptor open on the file for
reading and writing.
@end deftypefn
*/
int
mkstemps (char *pattern, int suffix_len)
{
static const char letters[]
= "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
static gcc_uint64_t value;
#ifdef HAVE_GETTIMEOFDAY
struct timeval tv;
#endif
char *XXXXXX;
size_t len;
int count;
len = strlen (pattern);
if ((int) len < 6 + suffix_len
|| strncmp (&pattern[len - 6 - suffix_len], "XXXXXX", 6))
{
return -1;
}
XXXXXX = &pattern[len - 6 - suffix_len];
#ifdef HAVE_GETTIMEOFDAY
/* Get some more or less random data. */
gettimeofday (&tv, NULL);
value += ((gcc_uint64_t) tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
#else
value += getpid ();
#endif
for (count = 0; count < TMP_MAX; ++count)
{
gcc_uint64_t v = value;
int fd;
/* 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];
fd = open (pattern, O_BINARY|O_RDWR|O_CREAT|O_EXCL, 0600);
if (fd >= 0)
/* The file does not exist. */
return fd;
if (errno != EEXIST
#ifdef EISDIR
&& errno != EISDIR
#endif
)
/* Fatal error (EPERM, ENOSPC etc). Doesn't make sense to loop. */
break;
/* This is a random value. It is only necessary that the next
TMP_MAX values generated by adding 7777 to VALUE are different
with (module 2^32). */
value += 7777;
}
/* We return the null string if we can't find a unique file name. */
pattern[0] = '\0';
return -1;
}
|