usr/src/lib/libpkg/common/canonize.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /* All Rights Reserved */
  29
  30
  31 #include <string.h>
  32
  33 #define isdot(x)        ((x[0] == '.') && (!x[1] || (x[1] == '/')))
  34 #define isdotdot(x)     ((x[0] == '.') && (x[1] == '.') && \
  35                             (!x[2] || (x[2] == '/')))
  36
  37 void
  38 canonize(char *file)
  39 {
  40         char *pt, *last;
  41         int level;
  42
  43         /* remove references such as "./" and "../" and "//" */
  44         for (pt = file; *pt; /* void */) {
  45                 if (isdot(pt))
  46                         (void) strcpy(pt, pt[1] ? pt+2 : pt+1);
  47                 else if (isdotdot(pt)) {
  48                         level = 0;
  49                         last = pt;
  50                         do {
  51                                 level++;
  52                                 last += 2;
  53                                 if (*last)
  54                                         last++;
  55                         } while (isdotdot(last));
  56                         --pt; /* point to previous '/' */
  57                         while (level--) {
  58                                 if (pt <= file)
  59                                         return;
  60                                 while ((*--pt != '/') && (pt > file))
  61                                         ;
  62                         }
  63                         if (*pt == '/')
  64                                 pt++;
  65                         (void) strcpy(pt, last);
  66                 } else {
  67                         while (*pt && (*pt != '/'))
  68                                 pt++;
  69                         if (*pt == '/') {
  70                                 while (pt[1] == '/')
  71                                         (void) strcpy(pt, pt+1);
  72                                 pt++;
  73                         }
  74                 }
  75         }
  76         if ((--pt > file) && (*pt == '/'))
  77                 *pt = '\0';
  78 }
  79
  80 void
  81 canonize_slashes(char *file)
  82 {
  83         char *pt;
  84
  85         /* remove references such as "//" */
  86         for (pt = file; *pt; /* void */) {
  87                 while (*pt && (*pt != '/'))
  88                         pt++;
  89                 if (*pt == '/') {
  90                         while (pt[1] == '/')
  91                                 (void) strcpy(pt, pt+1);
  92                         pt++;
  93                 }
  94         }
  95         if ((--pt > file) && (*pt == '/'))
  96                 *pt = '\0';
  97 }