blob: 465405e1982f11bc64551203003f8a738369cd72 [file] [log] [blame]
/* Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
* Portions Copyright © 1997-1999 Vita Nuova Limited
* Portions Copyright © 2000-2007 Vita Nuova Holdings Limited
* (www.vitanuova.com)
* Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
*
* Modified for the Akaros operating system:
* Copyright (c) 2013-2014 The Regents of the University of California
* Copyright (c) 2013-2015 Google Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE. */
#include <slab.h>
#include <kmalloc.h>
#include <kref.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include <error.h>
#include <cpio.h>
#include <pmap.h>
#include <smp.h>
#include <net/ip.h>
/*
* In place, rewrite name to compress multiple /, eliminate ., and process ..
*/
#define SEP(x) ((x)=='/' || (x) == 0)
char *cleanname(char *name)
{
char *p, *q, *dotdot;
int rooted, erasedprefix;
rooted = name[0] == '/';
erasedprefix = 0;
/*
* invariants:
* p points at beginning of path element we're considering.
* q points just past the last path element we wrote (no slash).
* dotdot points just past the point where .. cannot backtrack
* any further (no slash).
*/
p = q = dotdot = name + rooted;
while (*p) {
if (p[0] == '/') /* null element */
p++;
else if (p[0] == '.' && SEP(p[1])) {
if (p == name)
erasedprefix = 1;
/* don't count the separator in case it is nul */
p += 1;
} else if (p[0] == '.' && p[1] == '.' && SEP(p[2])) {
p += 2;
if (q > dotdot) { /* can backtrack */
while (--q > dotdot && *q != '/') ;
} else if (!rooted) { /* /.. is / but ./../ is .. */
if (q != name)
*q++ = '/';
*q++ = '.';
*q++ = '.';
dotdot = q;
}
/* erased entire path via dotdot */
if (q == name)
erasedprefix = 1;
} else { /* real path element */
if (q != name + rooted)
*q++ = '/';
while ((*q = *p) != '/' && *q != 0)
p++, q++;
}
}
if (q == name) /* empty string is really ``.'' */
*q++ = '.';
*q = '\0';
if (erasedprefix && name[0] == '#') {
/* this was not a #x device path originally - make it not one
* now */
memmove(name + 2, name, strlen(name) + 1);
name[0] = '.';
name[1] = '/';
}
return name;
}