pith/osdep/bldpath.c

   1 #if !defined(lint) && !defined(DOS)
   2 static char rcsid[] = "$Id: bldpath.c 934 2008-02-23 00:44:29Z hubert@u.washington.edu $";
   3 #endif
   4
   5 /*
   6  * ========================================================================
   7  * Copyright 2006-2008 University of Washington
   8  * Copyright 2013-2014 Eduardo Chappa
   9  *
  10  * Licensed under the Apache License, Version 2.0 (the "License");
  11  * you may not use this file except in compliance with the License.
  12  * You may obtain a copy of the License at
  13  *
  14  *     http://www.apache.org/licenses/LICENSE-2.0
  15  *
  16  * ========================================================================
  17  */
  18
  19 #include <system.h>
  20
  21 #if     STDC_HEADERS
  22 #include <ctype.h>
  23 #endif
  24
  25 #include "bldpath.h"
  26
  27 /*
  28  * Useful definitions
  29  */
  30 #ifdef  _WINDOWS
  31 #define ROOTED(S)       (*(S) == '\\' || (isalpha((unsigned char) (S)[0]) && (S)[1] == ':'))
  32 #define HOMERELATIVE(S) (FALSE)
  33 #else   /* UNIX */
  34 #define ROOTED(S)       (*(S) == '/')
  35 #define HOMERELATIVE(S) (*(S) == '~')
  36 #endif
  37
  38
  39
  40
  41 /*----------------------------------------------------------------------
  42       Paste together two pieces of a file name path
  43
  44   Args: pathbuf      -- Put the result here
  45         first_part   -- of path name
  46         second_part  -- of path name
  47         len          -- Length of pathbuf
  48
  49  Result: New path is in pathbuf.  Note that
  50          we don't have to check for /'s at end of first_part and beginning
  51          of second_part since multiple slashes are ok.
  52
  53 BUGS:  This is a first stab at dealing with fs naming dependencies, and others
  54 still exist.
  55   ----*/
  56 void
  57 build_path(char *pathbuf, char *first_part, char *second_part, size_t len)
  58 {
  59     if(!(pathbuf && len > 0))
  60       return;
  61
  62     pathbuf[0] = '\0';
  63
  64     if(!first_part || is_rooted_path(second_part)){
  65         if(second_part)
  66           strncpy(pathbuf, second_part, len-1);
  67
  68         pathbuf[len-1] = '\0';
  69     }
  70     else{
  71 #ifdef  _WINDOWS
  72         int i;
  73         char *orig_pathbuf = pathbuf;
  74
  75         for(i = 0; i < len-2 && first_part[i]; i++)
  76           *pathbuf++ = first_part[i];
  77
  78         if(second_part){
  79             if(i && first_part[i-1] == '\\'){   /* first part ended with \  */
  80                 if(*second_part == '\\')                /* and second starts with \ */
  81                   second_part++;                        /* else just append second  */
  82             }
  83             else if(*second_part != '\\')               /* no slash at all, so      */
  84               *pathbuf++ = '\\';                        /* insert one...            */
  85
  86             while(pathbuf-orig_pathbuf < len-1 && *second_part)
  87               *pathbuf++ = *second_part++;
  88         }
  89
  90         *pathbuf = '\0';
  91
  92 #else  /* UNIX */
  93
  94         size_t fpl = 0;
  95
  96         strncpy(pathbuf, first_part, len-2);
  97         pathbuf[len-2] = '\0';
  98         if(second_part){
  99             if(*pathbuf && pathbuf[(fpl=strlen(pathbuf))-1] != '/'){
 100                 pathbuf[fpl++] = '/';
 101                 pathbuf[fpl] = '\0';
 102             }
 103
 104             strncat(pathbuf, second_part, len-1-strlen(pathbuf));
 105         }
 106
 107         pathbuf[len-1] = '\0';
 108
 109 #endif
 110     }
 111 }
 112
 113
 114 /*----------------------------------------------------------------------
 115   Test to see if the given file path is absolute
 116
 117   Args: file -- file path to test
 118
 119  Result: TRUE if absolute, FALSE otw
 120
 121   ----*/
 122 int
 123 is_absolute_path(char *path)
 124 {
 125     return(path && (ROOTED(path) || HOMERELATIVE(path)));
 126 }
 127
 128
 129 /*
 130  * homedir_in_path - return pointer to point in path string where home dir
 131  *                   reference starts
 132  */
 133 int
 134 is_rooted_path(char *path)
 135 {
 136     return(path && ROOTED(path));
 137 }
 138
 139
 140 /*
 141  * homedir_in_path - return pointer to point in path string where home dir
 142  *                   reference starts
 143  */
 144 int
 145 is_homedir_path(char *path)
 146 {
 147     return(path && HOMERELATIVE(path));
 148 }
 149
 150
 151 /*
 152  * homedir_in_path - return pointer to point in path string where home dir
 153  *                   reference starts
 154  */
 155 char *
 156 homedir_in_path(char *path)
 157 {
 158 #ifdef  _WINDOWS
 159     return(NULL);
 160 #else   /* UNIX */
 161     char *p;
 162
 163     return((p = strchr(path, '~')) ? p : NULL);
 164 #endif
 165 }
 166
 167
 168 /*
 169  *
 170  */
 171 char *
 172 filename_parent_ref(char *s)
 173 {
 174 #ifdef  _WINDOWS
 175     return(strstr(s, "\\..\\"));
 176 #else   /* UNIX */
 177     return(strstr(s, "/../"));
 178 #endif
 179 }
 180
 181
 182 int
 183 filename_is_restricted(char *s)
 184 {
 185 #ifdef  _WINDOWS
 186     return(filename_parent_ref(s) != NULL);
 187 #else   /* UNIX */
 188     return(strchr("./~", s[0]) != NULL || filename_parent_ref(s) != NULL);
 189 #endif
 190 }