1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24*0Sstevel@tonic-gate * Use is subject to license terms. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 28*0Sstevel@tonic-gate 29*0Sstevel@tonic-gate /* Copyright (c) 1988 AT&T */ 30*0Sstevel@tonic-gate /* All Rights Reserved */ 31*0Sstevel@tonic-gate 32*0Sstevel@tonic-gate 33*0Sstevel@tonic-gate #pragma weak realpath = _realpath 34*0Sstevel@tonic-gate 35*0Sstevel@tonic-gate #include "synonyms.h" 36*0Sstevel@tonic-gate #include <sys/types.h> 37*0Sstevel@tonic-gate #include <dirent.h> 38*0Sstevel@tonic-gate #include <sys/param.h> 39*0Sstevel@tonic-gate #include <limits.h> 40*0Sstevel@tonic-gate #include <errno.h> 41*0Sstevel@tonic-gate #include <stdlib.h> 42*0Sstevel@tonic-gate #include <unistd.h> 43*0Sstevel@tonic-gate #include <string.h> 44*0Sstevel@tonic-gate 45*0Sstevel@tonic-gate /* 46*0Sstevel@tonic-gate * Canonicalize the path given in file_name, resolving away all symbolic link 47*0Sstevel@tonic-gate * components. Store the result into the buffer named by resolved_name, which 48*0Sstevel@tonic-gate * must be long enough (MAXPATHLEN bytes will suffice). Returns NULL 49*0Sstevel@tonic-gate * on failure and resolved_name on success. On failure, to maintain 50*0Sstevel@tonic-gate * compatibility with the past, the contents of file_name will be copied 51*0Sstevel@tonic-gate * into resolved_name. 52*0Sstevel@tonic-gate */ 53*0Sstevel@tonic-gate char * 54*0Sstevel@tonic-gate realpath(const char *file_name, char *resolved_name) 55*0Sstevel@tonic-gate { 56*0Sstevel@tonic-gate char cwd[PATH_MAX]; 57*0Sstevel@tonic-gate int len; 58*0Sstevel@tonic-gate 59*0Sstevel@tonic-gate if (file_name == NULL || resolved_name == NULL) { 60*0Sstevel@tonic-gate errno = EINVAL; 61*0Sstevel@tonic-gate return (NULL); 62*0Sstevel@tonic-gate } 63*0Sstevel@tonic-gate 64*0Sstevel@tonic-gate /* 65*0Sstevel@tonic-gate * Call resolvepath() to resolve all the symlinks in file_name, 66*0Sstevel@tonic-gate * eliminate embedded "." components, and collapse embedded ".." 67*0Sstevel@tonic-gate * components. We may be left with leading ".." components. 68*0Sstevel@tonic-gate */ 69*0Sstevel@tonic-gate if ((len = resolvepath(file_name, resolved_name, PATH_MAX)) < 0) { 70*0Sstevel@tonic-gate (void) strlcpy(resolved_name, file_name, PATH_MAX); 71*0Sstevel@tonic-gate return (NULL); /* errno set by resolvepath() */ 72*0Sstevel@tonic-gate } 73*0Sstevel@tonic-gate 74*0Sstevel@tonic-gate if (len >= PATH_MAX) /* "can't happen" */ 75*0Sstevel@tonic-gate len = PATH_MAX - 1; 76*0Sstevel@tonic-gate resolved_name[len] = '\0'; 77*0Sstevel@tonic-gate 78*0Sstevel@tonic-gate if (*resolved_name == '/') /* nothing more to do */ 79*0Sstevel@tonic-gate return (resolved_name); 80*0Sstevel@tonic-gate 81*0Sstevel@tonic-gate /* 82*0Sstevel@tonic-gate * Prepend the current working directory to the relative path. 83*0Sstevel@tonic-gate * If the relative path is not empty (or "."), collapse all of the 84*0Sstevel@tonic-gate * resulting embedded ".." components with trailing cwd components. 85*0Sstevel@tonic-gate * We know that getcwd() returns a path name free of symlinks. 86*0Sstevel@tonic-gate */ 87*0Sstevel@tonic-gate if (getcwd(cwd, sizeof (cwd)) == NULL) { 88*0Sstevel@tonic-gate (void) strlcpy(resolved_name, file_name, PATH_MAX); 89*0Sstevel@tonic-gate return (NULL); /* errno set by getcwd() */ 90*0Sstevel@tonic-gate } 91*0Sstevel@tonic-gate 92*0Sstevel@tonic-gate if (len != 0 && strcmp(resolved_name, ".") != 0) { 93*0Sstevel@tonic-gate char *relpath = resolved_name; 94*0Sstevel@tonic-gate char *endcwd = cwd + strlen(cwd); 95*0Sstevel@tonic-gate 96*0Sstevel@tonic-gate /* 97*0Sstevel@tonic-gate * Eliminate ".." components from the relative path 98*0Sstevel@tonic-gate * left-to-right, components from cwd right-to-left. 99*0Sstevel@tonic-gate */ 100*0Sstevel@tonic-gate relpath[len++] = '/'; 101*0Sstevel@tonic-gate while (len >= 3 && strncmp(relpath, "../", 3) == 0) { 102*0Sstevel@tonic-gate relpath += 3; 103*0Sstevel@tonic-gate len -= 3; 104*0Sstevel@tonic-gate while (*--endcwd != '/') 105*0Sstevel@tonic-gate continue; 106*0Sstevel@tonic-gate } 107*0Sstevel@tonic-gate if (len == 0) { 108*0Sstevel@tonic-gate /* the relative path was all ".." components */ 109*0Sstevel@tonic-gate *endcwd = '\0'; 110*0Sstevel@tonic-gate } else { 111*0Sstevel@tonic-gate /* there are non-null components on both sides */ 112*0Sstevel@tonic-gate relpath[--len] = '\0'; 113*0Sstevel@tonic-gate *endcwd++ = '/'; 114*0Sstevel@tonic-gate if (endcwd + len >= cwd + PATH_MAX) { 115*0Sstevel@tonic-gate (void) strlcpy(resolved_name, 116*0Sstevel@tonic-gate file_name, PATH_MAX); 117*0Sstevel@tonic-gate errno = ENAMETOOLONG; 118*0Sstevel@tonic-gate return (NULL); 119*0Sstevel@tonic-gate } 120*0Sstevel@tonic-gate (void) strcpy(endcwd, relpath); 121*0Sstevel@tonic-gate } 122*0Sstevel@tonic-gate } 123*0Sstevel@tonic-gate 124*0Sstevel@tonic-gate (void) strcpy(resolved_name, cwd); 125*0Sstevel@tonic-gate return (resolved_name); 126*0Sstevel@tonic-gate } 127