path.c

   1 /*
   2  * Copyright 2005 Timo Hirvonen
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  17  * 02111-1307, USA.
  18  */
  19
  20 #include <path.h>
  21 #include <xmalloc.h>
  22
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 void path_strip(char *str)
  27 {
  28         int i, s, d;
  29
  30         i = 0;
  31         if (str[0] == '/')
  32                 i = 1;
  33         while (str[i]) {
  34                 if (str[i] == '/') {
  35                         d = i;
  36                         s = i + 1;
  37                         while (str[s] && str[s] == '/')
  38                                 s++;
  39                         s--;
  40                         do {
  41                                 str[d++] = str[++s];
  42                         } while (str[s]);
  43                 } else if (i && str[i] == '.') {
  44                         if (str[i + 1] == '/') {
  45                                 d = i;
  46                                 s = i + 1;
  47                                 do {
  48                                         str[d++] = str[++s];
  49                                 } while (str[s]);
  50                         } else if (str[i + 1] == 0) {
  51                                 str[i] = 0;
  52                                 break;
  53                         } else if (str[i + 1] == '.' &&
  54                                   (str[i + 2] == '/' || str[i + 2] == 0)) {
  55                                 /* aaa/bbb/../ccc */
  56                                 /* aaa/ccc */
  57                                 if (str[i + 2]) {
  58                                         s = i + 3; /* ccc */
  59                                 } else {
  60                                         s = i + 2;
  61                                 }
  62                                 d = i - 1; /* /../ccc */
  63                                 do {
  64                                         if (d == 0)
  65                                                 break;
  66                                         d--;
  67                                 } while (str[d] != '/');
  68                                 d++;
  69                                 /* std[d] is bbb/../ccc */
  70                                 i = d;
  71                                 s--;
  72                                 do {
  73                                         str[d++] = str[++s];
  74                                 } while (str[s]);
  75                         } else {
  76                                 while (str[i] && str[i] != '/')
  77                                         i++;
  78                                 if (str[i])
  79                                         i++;
  80                         }
  81                 } else {
  82                         while (str[i] && str[i] != '/')
  83                                 i++;
  84                         if (str[i])
  85                                 i++;
  86                 }
  87         }
  88         if (i > 1 && str[i - 1] == '/')
  89                 str[i - 1] = 0;
  90 }
  91
  92 char *path_absolute(const char *src)
  93 {
  94         char *str;
  95
  96         if (src[0] == '/') {
  97                 /* already absolute */
  98                 str = xstrdup(src);
  99         } else {
 100                 char cwd[1024];
 101                 int src_len;
 102                 int cwd_len;
 103
 104                 if (getcwd(cwd, sizeof(cwd)) == NULL)
 105                         return NULL;
 106                 src_len = strlen(src);
 107                 cwd_len = strlen(cwd);
 108                 str = xnew(char, cwd_len + 1 + src_len + 1);
 109                 memcpy(str, cwd, cwd_len);
 110                 str[cwd_len] = '/';
 111                 memcpy(str + cwd_len + 1, src, src_len + 1);
 112         }
 113         path_strip(str);
 114         return str;
 115 }