| /* 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; |
| } |