config/pathsub.c

   1 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
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  31  * decision by deleting the provisions above and replace them with the notice
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  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37 /*
  38 ** Pathname subroutines.
  39 **
  40 ** Brendan Eich, 8/29/95
  41 */
  42 #include <assert.h>
  43 #include <sys/types.h>
  44 #include <dirent.h>
  45 #include <errno.h>
  46 #include <stdarg.h>
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50 #include <unistd.h>
  51 #include <sys/stat.h>
  52 #include "pathsub.h"
  53
  54 #ifdef USE_REENTRANT_LIBC
  55 #include <libc_r.h>
  56 #endif
  57
  58 #ifdef SUNOS4
  59 #include "sunos4.h"
  60 #endif
  61
  62 #ifndef D_INO
  63 #define D_INO   d_ino
  64 #endif
  65
  66 char *program;
  67
  68 void
  69 fail(char *format, ...)
  70 {
  71     int error;
  72     va_list ap;
  73
  74 #ifdef USE_REENTRANT_LIBC
  75     R_STRERROR_INIT_R();
  76 #endif
  77
  78     error = errno;
  79     fprintf(stderr, "%s: ", program);
  80     va_start(ap, format);
  81     vfprintf(stderr, format, ap);
  82     va_end(ap);
  83     if (error) {
  84
  85 #ifdef USE_REENTRANT_LIBC
  86     R_STRERROR_R(errno);
  87         fprintf(stderr, ": %s", r_strerror_r);
  88 #else
  89         fprintf(stderr, ": %s", strerror(errno));
  90 #endif
  91     }
  92
  93     putc('\n', stderr);
  94     exit(1);
  95 }
  96
  97 char *
  98 getcomponent(char *path, char *name)
  99 {
 100     if (*path == '\0')
 101         return 0;
 102     if (*path == '/') {
 103         *name++ = '/';
 104     } else {
 105         do {
 106             *name++ = *path++;
 107         } while (*path != '/' && *path != '\0');
 108     }
 109     *name = '\0';
 110     while (*path == '/')
 111         path++;
 112     return path;
 113 }
 114
 115 #ifdef LAME_READDIR
 116 #include <sys/param.h>
 117 /*
 118 ** The static buffer in Unixware's readdir is too small.
 119 */
 120 struct dirent *readdir(DIR *d)
 121 {
 122         static struct dirent *buf = NULL;
 123
 124         if(buf == NULL)
 125                 buf = (struct dirent *) malloc(sizeof(struct dirent) + MAXPATHLEN);
 126         return(readdir_r(d, buf));
 127 }
 128 #endif
 129
 130 char *
 131 ino2name(ino_t ino, char *dir)
 132 {
 133     DIR *dp;
 134     struct dirent *ep;
 135     char *name;
 136
 137     dp = opendir("..");
 138     if (!dp)
 139         fail("cannot read parent directory");
 140     for (;;) {
 141         if (!(ep = readdir(dp)))
 142             fail("cannot find current directory");
 143         if (ep->D_INO == ino)
 144             break;
 145     }
 146     name = xstrdup(ep->d_name);
 147     closedir(dp);
 148     return name;
 149 }
 150
 151 void *
 152 xmalloc(size_t size)
 153 {
 154     void *p = malloc(size);
 155     if (!p)
 156         fail("cannot allocate %u bytes", size);
 157     return p;
 158 }
 159
 160 char *
 161 xstrdup(char *s)
 162 {
 163     return strcpy(xmalloc(strlen(s) + 1), s);
 164 }
 165
 166 char *
 167 xbasename(char *path)
 168 {
 169     char *cp;
 170
 171     while ((cp = strrchr(path, '/')) && cp[1] == '\0')
 172         *cp = '\0';
 173     if (!cp) return path;
 174     return cp + 1;
 175 }
 176
 177 void
 178 xchdir(char *dir)
 179 {
 180     if (chdir(dir) < 0)
 181         fail("cannot change directory to %s", dir);
 182 }
 183
 184 int
 185 relatepaths(char *from, char *to, char *outpath)
 186 {
 187     char *cp, *cp2;
 188     int len;
 189     char buf[NAME_MAX];
 190
 191     assert(*from == '/' && *to == '/');
 192     for (cp = to, cp2 = from; *cp == *cp2; cp++, cp2++)
 193         if (*cp == '\0')
 194             break;
 195     while (cp[-1] != '/')
 196         cp--, cp2--;
 197     if (cp - 1 == to) {
 198         /* closest common ancestor is /, so use full pathname */
 199         len = strlen(strcpy(outpath, to));
 200         if (outpath[len] != '/') {
 201             outpath[len++] = '/';
 202             outpath[len] = '\0';
 203         }
 204     } else {
 205         len = 0;
 206         while ((cp2 = getcomponent(cp2, buf)) != 0) {
 207             strcpy(outpath + len, "../");
 208             len += 3;
 209         }
 210         while ((cp = getcomponent(cp, buf)) != 0) {
 211             sprintf(outpath + len, "%s/", buf);
 212             len += strlen(outpath + len);
 213         }
 214     }
 215     return len;
 216 }
 217
 218 void
 219 reversepath(char *inpath, char *name, int len, char *outpath)
 220 {
 221     char *cp, *cp2;
 222     char buf[NAME_MAX];
 223     struct stat sb;
 224
 225     cp = strcpy(outpath + PATH_MAX - (len + 1), name);
 226     cp2 = inpath;
 227     while ((cp2 = getcomponent(cp2, buf)) != 0) {
 228         if (strcmp(buf, ".") == 0)
 229             continue;
 230         if (strcmp(buf, "..") == 0) {
 231             if (stat(".", &sb) < 0)
 232                 fail("cannot stat current directory");
 233             name = ino2name(sb.st_ino, "..");
 234             len = strlen(name);
 235             cp -= len + 1;
 236             strcpy(cp, name);
 237             cp[len] = '/';
 238             free(name);
 239             xchdir("..");
 240         } else {
 241             cp -= 3;
 242             strncpy(cp, "../", 3);
 243             xchdir(buf);
 244         }
 245     }
 246     strcpy(outpath, cp);
 247 }