winsup/cygwin/winf.cc

   1 /* winf.cc
   2
   3 This software is a copyrighted work licensed under the terms of the
   4 Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
   5 details. */
   6
   7 #include "winsup.h"
   8 #include <stdlib.h>
   9 #include "cygerrno.h"
  10 #include "security.h"
  11 #include "path.h"
  12 #include "fhandler.h"
  13 #include "dtable.h"
  14 #include "cygheap.h"
  15 #include "tls_pbuf.h"
  16 #include "winf.h"
  17 #include "sys/cygwin.h"
  18
  19 void
  20 linebuf::finish (bool cmdlenoverflow_ok)
  21 {
  22   if (!ix)
  23     add ("", 1);
  24   else
  25     {
  26       if (ix-- > MAXCYGWINCMDLEN && cmdlenoverflow_ok)
  27         ix = MAXCYGWINCMDLEN - 1;
  28       buf[ix] = '\0';
  29     }
  30 }
  31
  32 void
  33 linebuf::add (const char *what, int len)
  34 {
  35   size_t newix = ix + len;
  36   if (newix >= alloced || !buf)
  37     {
  38       alloced += LINE_BUF_CHUNK + newix;
  39       buf = (char *) realloc (buf, alloced + 1);
  40     }
  41   memcpy (buf + ix, what, len);
  42   ix = newix;
  43   buf[ix] = '\0';
  44 }
  45
  46 void
  47 linebuf::prepend (const char *what, int len)
  48 {
  49   int buflen;
  50   size_t newix;
  51   if ((newix = ix + len) >= alloced)
  52     {
  53       alloced += LINE_BUF_CHUNK + newix;
  54       buf = (char *) realloc (buf, alloced + 1);
  55       buf[ix] = '\0';
  56     }
  57   if ((buflen = strlen (buf)))
  58       memmove (buf + len, buf, buflen + 1);
  59   else
  60       buf[newix] = '\0';
  61   memcpy (buf, what, len);
  62   ix = newix;
  63 }
  64
  65 bool
  66 linebuf::fromargv (av& newargv, const char *real_path, bool cmdlenoverflow_ok)
  67 {
  68   bool success = true;
  69   for (int i = 0; i < newargv.argc; i++)
  70     {
  71       char *p = NULL;
  72       const char *a;
  73
  74       a = i ? newargv[i] : (char *) real_path;
  75       int len = strlen (a);
  76       if (len != 0 && !strpbrk (a, " \t\n\r\""))
  77         add (a, len);
  78       else
  79         {
  80           add ("\"", 1);
  81           /* Handle embedded special characters " and \.
  82              A " is always preceded by a \.
  83              A \ is not special unless it precedes a ".  If it does,
  84              then all preceding \'s must be doubled to avoid having
  85              the Windows command line parser interpret the \ as quoting
  86              the ".  This rule applies to a string of \'s before the end
  87              of the string, since cygwin/windows uses a " to delimit the
  88              argument. */
  89           for (; (p = strpbrk (a, "\"\\")); a = ++p)
  90             {
  91               add (a, p - a);
  92               /* Find length of string of backslashes */
  93               int n = strspn (p, "\\");
  94               if (!n)
  95                 add ("\\\"", 2);        /* No backslashes, so it must be a ".
  96                                                The " has to be protected with a backslash. */
  97               else
  98                 {
  99                   add (p, n);   /* Add the run of backslashes */
 100                   /* Need to double up all of the preceding
 101                      backslashes if they precede a quote or EOS. */
 102                   if (!p[n] || p[n] == '"')
 103                     add (p, n);
 104                   p += n - 1;           /* Point to last backslash */
 105                 }
 106             }
 107           if (*a)
 108             add (a);
 109           add ("\"", 1);
 110         }
 111       add (" ", 1);
 112     }
 113
 114   finish (cmdlenoverflow_ok);
 115
 116   if (ix >= MAXWINCMDLEN)
 117     {
 118       debug_printf ("command line too long (>32K), return E2BIG");
 119       set_errno (E2BIG);
 120       success = false;
 121     }
 122
 123   return success;
 124 }
 125
 126 int
 127 av::unshift (const char *what)
 128 {
 129   char **av;
 130   av = (char **) crealloc (argv, (argc + 2) * sizeof (char *));
 131   if (!av)
 132     return 0;
 133
 134   argv = av;
 135   memmove (argv + 1, argv, (argc + 1) * sizeof (char *));
 136   *argv = cstrdup1 (what);
 137   calloced++;
 138   argc++;
 139   return 1;
 140 }