ReactOS  0.4.14-dev-552-g2fad488
mkstemps.c
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1 /* Copyright (C) 1991, 1992, 1996, 1998 Free Software Foundation, Inc.
2  This file is derived from mkstemp.c from the GNU C Library.
3 
4  The GNU C Library is free software; you can redistribute it and/or
5  modify it under the terms of the GNU Lesser General Public
6  License as published by the Free Software Foundation; either
7  version 2.1 of the License, or (at your option) any later version.
8 
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  Lesser General Public License for more details.
13 
14  You should have received a copy of the GNU Lesser General Public
15  License along with the GNU C Library; if not, write to the Free
16  Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17  Boston, MA 02110-1301, USA.
18 */
19 
20 #include <sys/types.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <errno.h>
24 #include <stdio.h>
25 #include <fcntl.h>
26 
27 #ifdef _WIN32
28  #include <io.h>
29  #include <process.h>
30 #else
31  #include <unistd.h>
32  #include <sys/time.h>
33 #endif
34 
35 /* We need to provide a type for gcc_uint64_t. */
36 #ifdef __GNUC__
37 __extension__ typedef unsigned long long gcc_uint64_t;
38 #else
39 typedef unsigned long gcc_uint64_t;
40 #endif
41 
42 #ifndef TMP_MAX
43 #define TMP_MAX 16384
44 #endif
45 
46 /* if O_BINARY is not defined, the system is probably not expecting any such flag */
47 #ifndef O_BINARY
48 #define O_BINARY 0
49 #endif
50 
51 /*
52 
53 @deftypefn Replacement int mkstemps (char *@var{template}, int @var{suffix_len})
54 
55 Generate a unique temporary file name from @var{template}.
56 @var{template} has the form:
57 
58 @example
59  @var{path}/ccXXXXXX@var{suffix}
60 @end example
61 
62 @var{suffix_len} tells us how long @var{suffix} is (it can be zero
63 length). The last six characters of @var{template} before @var{suffix}
64 must be @samp{XXXXXX}; they are replaced with a string that makes the
65 filename unique. Returns a file descriptor open on the file for
66 reading and writing.
67 
68 @end deftypefn
69 
70 */
71 
72 int
74  char *template,
75  int suffix_len)
76 {
77  static const char letters[]
78  = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
79  static gcc_uint64_t value;
80 #ifdef HAVE_GETTIMEOFDAY
81  struct timeval tv;
82 #endif
83  char *XXXXXX;
84  size_t len;
85  int count;
86 
87  len = strlen (template);
88 
89  if ((int) len < 6 + suffix_len
90  || strncmp (&template[len - 6 - suffix_len], "XXXXXX", 6))
91  {
92  printf("wrong parameter\n");
93  return -1;
94  }
95 
96  XXXXXX = &template[len - 6 - suffix_len];
97 
98 #ifdef HAVE_GETTIMEOFDAY
99  /* Get some more or less random data. */
100  gettimeofday (&tv, NULL);
101  value += ((gcc_uint64_t) tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
102 #else
103  value += getpid ();
104 #endif
105 
106  for (count = 0; count < TMP_MAX; ++count)
107  {
108  gcc_uint64_t v = value;
109  int fd;
110 
111  /* Fill in the random bits. */
112  XXXXXX[0] = letters[v % 62];
113  v /= 62;
114  XXXXXX[1] = letters[v % 62];
115  v /= 62;
116  XXXXXX[2] = letters[v % 62];
117  v /= 62;
118  XXXXXX[3] = letters[v % 62];
119  v /= 62;
120  XXXXXX[4] = letters[v % 62];
121  v /= 62;
122  XXXXXX[5] = letters[v % 62];
123 
124 #ifdef VMS
125  fd = open (template, O_RDWR|O_CREAT|O_EXCL, 0600, "fop=tmd");
126 #else
127  fd = open (template, O_RDWR|O_CREAT|O_EXCL|O_BINARY, 0600);
128 #endif
129  if (fd >= 0)
130  /* The file does not exist. */
131  return fd;
132 
133  /* This is a random value. It is only necessary that the next
134  TMP_MAX values generated by adding 7777 to VALUE are different
135  with (module 2^32). */
136  value += 7777;
137  }
138 
139  /* We return the null string if we can't find a unique file name. */
140  template[0] = '\0';
141  return -1;
142 }
#define TMP_MAX
Definition: mkstemps.c:43
#define open
Definition: acwin.h:95
ACPI_SIZE strlen(const char *String)
Definition: utclib.c:269
GLuint GLuint GLsizei count
Definition: gl.h:1545
unsigned long tv_sec
Definition: linux.h:1738
static int fd
Definition: io.c:51
#define gettimeofday(tv, tz)
Definition: adns_win32.h:159
int mkstemps(char *template, int suffix_len)
Definition: mkstemps.c:73
smooth NULL
Definition: ftsmooth.c:416
unsigned long tv_usec
Definition: linux.h:1739
#define O_EXCL
Definition: fcntl.h:40
_CRTIMP int __cdecl getpid(void)
unsigned long gcc_uint64_t
Definition: mkstemps.c:39
int strncmp(const char *String1, const char *String2, ACPI_SIZE Count)
Definition: utclib.c:534
GLenum GLsizei len
Definition: glext.h:6722
GLsizei const GLfloat * value
Definition: glext.h:6069
const GLdouble * v
Definition: gl.h:2040
#define O_RDWR
Definition: fcntl.h:36
#define O_BINARY
Definition: mkstemps.c:48
#define O_CREAT
Definition: acwin.h:110
#define printf
Definition: config.h:203