reactos/lib/msvcrt/io/mktemp.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  *              Copyright (C) 1994 DJ Delorie, see COPYING.DJ for details
   4  * PROJECT:     ReactOS system libraries
   5  * FILE:        lib/msvcrt/io/mktemp.c
   6  * PURPOSE:     Makes a temp file based on a template
   7  * PROGRAMER:   DJ Delorie
   8                                 Boudewijn Dekker
   9  * UPDATE HISTORY:
  10  *              28/12/98: Appropriated for the Reactos Kernel
  11  */
  12
  13 /* Copyright (C) 1996 DJ Delorie, see COPYING.DJ for details */
  14 /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
  15
  16 #include <msvcrt/stdio.h>
  17 #include <msvcrt/string.h>
  18 #include <msvcrt/io.h>
  19
  20 #define NDEBUG
  21 #include <msvcrt/msvcrtdbg.h>
  22
  23
  24 char* _mktemp (char *_template)
  25 {
  26   static int count = 0;
  27   char *cp, *dp;
  28   int i, len, xcount, loopcnt;
  29
  30   DPRINT("_mktemp('%s')\n", _template);
  31   len = strlen (_template);
  32   cp = _template + len;
  33
  34   xcount = 0;
  35   while (xcount < 6 && cp > _template && cp[-1] == 'X')
  36     xcount++, cp--;
  37
  38   if (xcount) {
  39     dp = cp;
  40     while (dp > _template && dp[-1] != '/' && dp[-1] != '\\' && dp[-1] != ':')
  41       dp--;
  42
  43     /* Keep the first characters of the template, but turn the rest into
  44        Xs.  */
  45     while (cp > dp + 8 - xcount) {
  46       *--cp = 'X';
  47       xcount = (xcount >= 6) ? 6 : 1 + xcount;
  48     }
  49
  50     /* If dots occur too early -- squash them.  */
  51     while (dp < cp) {
  52       if (*dp == '.') *dp = 'a';
  53       dp++;
  54     }
  55
  56     /* Try to add ".tmp" to the filename.  Truncate unused Xs.  */
  57     if (cp + xcount + 3 < _template + len)
  58       strcpy (cp + xcount, ".tmp");
  59     else
  60       cp[xcount] = 0;
  61
  62     /* This loop can run up to 2<<(5*6) times, or about 10^9 times.  */
  63     for (loopcnt = 0; loopcnt < (1 << (5 * xcount)); loopcnt++) {
  64       int c = count++;
  65       for (i = 0; i < xcount; i++, c >>= 5)
  66         cp[i] = "abcdefghijklmnopqrstuvwxyz012345"[c & 0x1f];
  67       if (_access(_template,0) == -1)
  68         return _template;
  69     }
  70   }
  71
  72   /* Failure:  truncate the template and return NULL.  */
  73   *_template = 0;
  74   return 0;
  75 }
  76
  77 wchar_t* _wmktemp (wchar_t *_template)
  78 {
  79   static int count = 0;
  80   wchar_t *cp, *dp;
  81   int i, len, xcount, loopcnt;
  82
  83   DPRINT("_wmktemp('%S')\n", _template);
  84   len = wcslen (_template);
  85   cp = _template + len;
  86
  87   xcount = 0;
  88   while (xcount < 6 && cp > _template && cp[-1] == L'X')
  89     xcount++, cp--;
  90
  91   if (xcount) {
  92     dp = cp;
  93     while (dp > _template && dp[-1] != L'/' && dp[-1] != L'\\' && dp[-1] != L':')
  94       dp--;
  95
  96     /* Keep the first characters of the template, but turn the rest into
  97        Xs.  */
  98     while (cp > dp + 8 - xcount) {
  99       *--cp = L'X';
 100       xcount = (xcount >= 6) ? 6 : 1 + xcount;
 101     }
 102
 103     /* If dots occur too early -- squash them.  */
 104     while (dp < cp) {
 105       if (*dp == L'.') *dp = L'a';
 106       dp++;
 107     }
 108
 109     /* Try to add ".tmp" to the filename.  Truncate unused Xs.  */
 110     if (cp + xcount + 3 < _template + len)
 111       wcscpy (cp + xcount, L".tmp");
 112     else
 113       cp[xcount] = 0;
 114
 115     /* This loop can run up to 2<<(5*6) times, or about 10^9 times.  */
 116     for (loopcnt = 0; loopcnt < (1 << (5 * xcount)); loopcnt++) {
 117       int c = count++;
 118       for (i = 0; i < xcount; i++, c >>= 5)
 119         cp[i] = L"abcdefghijklmnopqrstuvwxyz012345"[c & 0x1f];
 120       if (_waccess(_template,0) == -1)
 121         return _template;
 122     }
 123   }
 124
 125   /* Failure:  truncate the template and return NULL.  */
 126   *_template = 0;
 127   return 0;
 128 }