source/lib/path.cpp

   1 /* Copyright (c) 2010 Wildfire Games
   2  *
   3  * Permission is hereby granted, free of charge, to any person obtaining
   4  * a copy of this software and associated documentation files (the
   5  * "Software"), to deal in the Software without restriction, including
   6  * without limitation the rights to use, copy, modify, merge, publish,
   7  * distribute, sublicense, and/or sell copies of the Software, and to
   8  * permit persons to whom the Software is furnished to do so, subject to
   9  * the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included
  12  * in all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  17  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  18  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  19  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  20  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21  */
  22
  23 /*
  24  * helper functions for path strings.
  25  */
  26
  27 #include "precompiled.h"
  28 #include "lib/path.h"
  29
  30 #include <cstring>
  31 #include <cerrno>
  32
  33 static const StatusDefinition pathStatusDefinitions[] = {
  34         { ERR::PATH_CHARACTER_ILLEGAL, L"illegal path character" },
  35         { ERR::PATH_CHARACTER_UNSAFE, L"unsafe path character" },
  36         { ERR::PATH_NOT_FOUND, L"path not found" },
  37         { ERR::PATH_MIXED_SEPARATORS, L"path contains both slash and backslash separators" }
  38 };
  39 STATUS_ADD_DEFINITIONS(pathStatusDefinitions);
  40
  41
  42 static bool path_is_dir_sep(wchar_t c)
  43 {
  44         if(c == '/' || c == '\\')
  45                 return true;
  46         return false;
  47 }
  48
  49 // is s2 a subpath of s1, or vice versa?
  50 // (equal counts as subpath)
  51 bool path_is_subpath(const wchar_t* s1, const wchar_t* s2)
  52 {
  53         // make sure s1 is the shorter string
  54         if(wcslen(s1) > wcslen(s2))
  55                 std::swap(s1, s2);
  56
  57         wchar_t c1 = 0, last_c1, c2;
  58         for(;;)
  59         {
  60                 last_c1 = c1;
  61                 c1 = *s1++, c2 = *s2++;
  62
  63                 // end of s1 reached:
  64                 if(c1 == '\0')
  65                 {
  66                         // s1 matched s2 up until:
  67                         if((c2 == '\0') ||      // its end (i.e. they're equal length) OR
  68                                 path_is_dir_sep(c2) ||          // start of next component OR
  69                                 path_is_dir_sep(last_c1))       // ", but both have a trailing slash
  70                                 // => is subpath
  71                                 return true;
  72                 }
  73
  74                 // mismatch => is not subpath
  75                 if(c1 != c2)
  76                         return false;
  77         }
  78 }
  79
  80
  81 //-----------------------------------------------------------------------------
  82
  83 // return pointer to the name component within path (i.e. skips over all
  84 // characters up to the last dir separator, if any).
  85 const wchar_t* path_name_only(const wchar_t* path)
  86 {
  87         const wchar_t* slash1 = wcsrchr(path, '/');
  88         const wchar_t* slash2 = wcsrchr(path, '\\');
  89         // neither present, it's a filename only
  90         if(!slash1 && !slash2)
  91                 return path;
  92
  93         // return name, i.e. component after the last slash
  94         const wchar_t* name = std::max(slash1, slash2)+1;
  95         return name;
  96 }
  97
  98
  99 /*static*/ Status Path::Validate(String::value_type c)
 100 {
 101         if(c < 32)
 102                 return ERR::PATH_CHARACTER_UNSAFE;
 103
 104 #if !OS_WIN
 105         if(c >= UCHAR_MAX)
 106                 return ERR::PATH_CHARACTER_UNSAFE;
 107 #endif
 108
 109         switch(c)
 110         {
 111         case '\\':
 112         case '/':
 113         case ':':
 114         case '"':
 115         case '?':
 116         case '*':
 117         case '<':
 118         case '>':
 119         case '|':
 120         case '^':
 121                 return ERR::PATH_CHARACTER_ILLEGAL;
 122
 123         default:
 124                 return INFO::OK;
 125         }
 126 }