-/* OPENBSD ORIGINAL: lib/libc/stdlib/realpath.c */
-
/*
- * Copyright (c) 2003 Constantin S. Svintsoff <kostik@iclub.nsu.ru>
+ * Copyright (c) 1994
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
- * 3. The names of the authors may not be used to endorse or promote
- * products derived from this software without specific prior written
- * permission.
*
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
#if !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH)
+#if defined(LIBC_SCCS) && !defined(lint)
+static char *rcsid = "$OpenBSD: realpath.c,v 1.5 2001/06/27 00:58:56 lebel Exp $";
+#endif /* LIBC_SCCS and not lint */
+
#include <sys/param.h>
#include <sys/stat.h>
#include <errno.h>
+#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/*
- * char *realpath(const char *path, char resolved[PATH_MAX]);
+ * MAXSYMLINKS
+ */
+#ifndef MAXSYMLINKS
+#define MAXSYMLINKS 5
+#endif
+
+/*
+ * char *realpath(const char *path, char resolved_path[MAXPATHLEN]);
*
* Find the real name of path, by removing all ".", ".." and symlink
* components. Returns (resolved) on success, or (NULL) on failure,
* in which case the path which caused trouble is left in (resolved).
*/
char *
-realpath(const char *path, char resolved[PATH_MAX])
+realpath(const char *path, char *resolved)
{
struct stat sb;
- char *p, *q, *s;
- size_t left_len, resolved_len;
- unsigned symlinks;
- int serrno, slen;
- char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];
+ int fd, n, rootd, serrno = 0;
+ char *p, *q, wbuf[MAXPATHLEN], start[MAXPATHLEN];
+ int symlinks = 0;
- serrno = errno;
- symlinks = 0;
- if (path[0] == '/') {
- resolved[0] = '/';
- resolved[1] = '\0';
- if (path[1] == '\0')
- return (resolved);
- resolved_len = 1;
- left_len = strlcpy(left, path + 1, sizeof(left));
- } else {
- if (getcwd(resolved, PATH_MAX) == NULL) {
- strlcpy(resolved, ".", PATH_MAX);
- return (NULL);
- }
- resolved_len = strlen(resolved);
- left_len = strlcpy(left, path, sizeof(left));
- }
- if (left_len >= sizeof(left) || resolved_len >= PATH_MAX) {
- errno = ENAMETOOLONG;
+ /* Save the starting point. */
+ getcwd(start,MAXPATHLEN);
+ if ((fd = open(".", O_RDONLY)) < 0) {
+ (void)strcpy(resolved, ".");
return (NULL);
}
+ close(fd);
/*
- * Iterate over path components in `left'.
+ * Find the dirname and basename from the path to be resolved.
+ * Change directory to the dirname component.
+ * lstat the basename part.
+ * if it is a symlink, read in the value and loop.
+ * if it is a directory, then change to that directory.
+ * get the current directory name and append the basename.
*/
- while (left_len != 0) {
- /*
- * Extract the next path component and adjust `left'
- * and its length.
- */
- p = strchr(left, '/');
- s = p ? p : left + left_len;
- if (s - left >= sizeof(next_token)) {
- errno = ENAMETOOLONG;
- return (NULL);
- }
- memcpy(next_token, left, s - left);
- next_token[s - left] = '\0';
- left_len -= s - left;
- if (p != NULL)
- memmove(left, s + 1, left_len + 1);
- if (resolved[resolved_len - 1] != '/') {
- if (resolved_len + 1 >= PATH_MAX) {
- errno = ENAMETOOLONG;
- return (NULL);
- }
- resolved[resolved_len++] = '/';
- resolved[resolved_len] = '\0';
- }
- if (next_token[0] == '\0')
- continue;
- else if (strcmp(next_token, ".") == 0)
- continue;
- else if (strcmp(next_token, "..") == 0) {
- /*
- * Strip the last path component except when we have
- * single "/"
- */
- if (resolved_len > 1) {
- resolved[resolved_len - 1] = '\0';
- q = strrchr(resolved, '/') + 1;
- *q = '\0';
- resolved_len = q - resolved;
- }
- continue;
+ strlcpy(resolved, path, MAXPATHLEN);
+loop:
+ q = strrchr(resolved, '/');
+ if (q != NULL) {
+ p = q + 1;
+ if (q == resolved)
+ q = "/";
+ else {
+ do {
+ --q;
+ } while (q > resolved && *q == '/');
+ q[1] = '\0';
+ q = resolved;
}
+ if (chdir(q) < 0)
+ goto err1;
+ } else
+ p = resolved;
- /*
- * Append the next path component and lstat() it. If
- * lstat() fails we still can return successfully if
- * there are no more path components left.
- */
- resolved_len = strlcat(resolved, next_token, PATH_MAX);
- if (resolved_len >= PATH_MAX) {
- errno = ENAMETOOLONG;
- return (NULL);
- }
- if (lstat(resolved, &sb) != 0) {
- if (errno == ENOENT && p == NULL) {
- errno = serrno;
- return (resolved);
- }
- return (NULL);
- }
+ /* Deal with the last component. */
+ if (lstat(p, &sb) == 0) {
if (S_ISLNK(sb.st_mode)) {
- if (symlinks++ > MAXSYMLINKS) {
- errno = ELOOP;
- return (NULL);
- }
- slen = readlink(resolved, symlink, sizeof(symlink) - 1);
- if (slen < 0)
- return (NULL);
- symlink[slen] = '\0';
- if (symlink[0] == '/') {
- resolved[1] = 0;
- resolved_len = 1;
- } else if (resolved_len > 1) {
- /* Strip the last path component. */
- resolved[resolved_len - 1] = '\0';
- q = strrchr(resolved, '/') + 1;
- *q = '\0';
- resolved_len = q - resolved;
- }
-
- /*
- * If there are any path components left, then
- * append them to symlink. The result is placed
- * in `left'.
- */
- if (p != NULL) {
- if (symlink[slen - 1] != '/') {
- if (slen + 1 >= sizeof(symlink)) {
- errno = ENAMETOOLONG;
- return (NULL);
- }
- symlink[slen] = '/';
- symlink[slen + 1] = 0;
- }
- left_len = strlcat(symlink, left, sizeof(left));
- if (left_len >= sizeof(left)) {
- errno = ENAMETOOLONG;
- return (NULL);
- }
+ if (++symlinks > MAXSYMLINKS) {
+ serrno = ELOOP;
+ goto err1;
}
- left_len = strlcpy(left, symlink, sizeof(left));
+ n = readlink(p, resolved, MAXPATHLEN-1);
+ if (n < 0)
+ goto err1;
+ resolved[n] = '\0';
+ goto loop;
+ }
+ if (S_ISDIR(sb.st_mode)) {
+ if (chdir(p) < 0)
+ goto err1;
+ p = "";
}
}
/*
- * Remove trailing slash except when the resolved pathname
- * is a single "/".
+ * Save the last component name and get the full pathname of
+ * the current directory.
+ */
+ (void)strcpy(wbuf, p);
+ if (getcwd(resolved, MAXPATHLEN) == 0)
+ goto err1;
+
+ /*
+ * Join the two strings together, ensuring that the right thing
+ * happens if the last component is empty, or the dirname is root.
*/
- if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
- resolved[resolved_len - 1] = '\0';
+ if (resolved[0] == '/' && resolved[1] == '\0')
+ rootd = 1;
+ else
+ rootd = 0;
+
+ if (*wbuf) {
+ if (strlen(resolved) + strlen(wbuf) + rootd + 1 > MAXPATHLEN) {
+ serrno = ENAMETOOLONG;
+ goto err1;
+ }
+ if (rootd == 0)
+ (void)strcat(resolved, "/");
+ (void)strcat(resolved, wbuf);
+ }
+
+ /* Go back to where we came from. */
+ if (chdir(start) < 0) {
+ serrno = errno;
+ goto err2;
+ }
return (resolved);
+
+err1: chdir(start);
+err2: errno = serrno;
+ return (NULL);
}
#endif /* !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH) */
andersk / gssapi-openssh.git / blobdiff