lib/sh/makepath.c

   1 /* makepath.c - glue PATH and DIR together into a full pathname. */
   2
   3 /* Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software; you can redistribute it and/or modify it under
   8    the terms of the GNU General Public License as published by the Free
   9    Software Foundation; either version 2, or (at your option) any later
  10    version.
  11
  12    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  13    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15    for more details.
  16
  17    You should have received a copy of the GNU General Public License along
  18    with Bash; see the file COPYING.  If not, write to the Free Software
  19    Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  20
  21 #include <config.h>
  22
  23 #if defined (HAVE_UNISTD_H)
  24 #  ifdef _MINIX
  25 #    include <sys/types.h>
  26 #  endif
  27 #  include <unistd.h>
  28 #endif
  29
  30 #include <bashansi.h>
  31 #include "shell.h"
  32
  33 #include <tilde/tilde.h>
  34
  35 #ifndef NULL
  36 #  define NULL 0
  37 #endif
  38
  39 /* MAKE SURE THESE AGREE WITH ../../externs.h. */
  40
  41 #ifndef MP_DOTILDE
  42 #  define MP_DOTILDE    0x01
  43 #  define MP_DOCWD      0x02
  44 #  define MP_RMDOT      0x04
  45 #endif
  46
  47 extern char *get_working_directory __P((char *));
  48
  49 /* Take PATH, an element from, e.g., $CDPATH, and DIR, a directory name,
  50    and paste them together into PATH/DIR.  Tilde expansion is performed on
  51    PATH if (flags & MP_DOTILDE) is non-zero.  If PATH is NULL or the empty
  52    string, it is converted to the current directory.  A full pathname is
  53    used if (flags & MP_DOCWD) is non-zero, otherwise `./' is used.  If
  54    (flags & MP_RMDOT) is non-zero, any `./' is removed from the beginning
  55    of DIR. */
  56
  57 #define MAKEDOT() \
  58   do { \
  59     xpath = (char *)xmalloc (2); \
  60     xpath[0] = '.'; \
  61     xpath[1] = '\0'; \
  62     pathlen = 1; \
  63   } while (0)
  64
  65 char *
  66 sh_makepath (path, dir, flags)
  67      const char *path, *dir;
  68      int flags;
  69 {
  70   int dirlen, pathlen;
  71   char *ret, *xpath, *xdir, *r, *s;
  72
  73   if (path == 0 || *path == '\0')
  74     {
  75       if (flags & MP_DOCWD)
  76         {
  77           xpath = get_working_directory ("sh_makepath");
  78           if (xpath == 0)
  79             {
  80               ret = get_string_value ("PWD");
  81               if (ret)
  82                 xpath = savestring (ret);
  83             }
  84           if (xpath == 0)
  85             MAKEDOT();
  86           else
  87             pathlen = strlen (xpath);
  88         }
  89       else
  90         MAKEDOT();
  91     }
  92   else
  93     {
  94       xpath = ((flags & MP_DOTILDE) && *path == '~') ? bash_tilde_expand (path) : (char *)path;
  95       pathlen = strlen (xpath);
  96     }
  97
  98   xdir = (char *)dir;
  99   dirlen = strlen (xdir);
 100   if ((flags & MP_RMDOT) && dir[0] == '.' && dir[1] == '/')
 101     {
 102       xdir += 2;
 103       dirlen -= 2;
 104     }
 105
 106   r = ret = (char *)xmalloc (2 + dirlen + pathlen);
 107   s = xpath;
 108   while (*s)
 109     *r++ = *s++;
 110   if (s[-1] != '/')
 111     *r++ = '/';
 112   s = xdir;
 113   while (*r++ = *s++)
 114     ;
 115   if (xpath != path)
 116     free (xpath);
 117   return (ret);
 118 }