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35 #if !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH)
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char *rcsid = "$OpenBSD: realpath.c,v 1.10 2003/08/01 21:04:59 millert Exp $";
39 #endif /* LIBC_SCCS and not lint */
41 #include <sys/param.h>
58 * char *realpath(const char *path, char resolved_path[MAXPATHLEN]);
60 * Find the real name of path, by removing all ".", ".." and symlink
61 * components. Returns (resolved) on success, or (NULL) on failure,
62 * in which case the path which caused trouble is left in (resolved).
65 realpath(const char *path, char *resolved)
68 int fd, n, needslash, serrno = 0;
69 char *p, *q, wbuf[MAXPATHLEN], start[MAXPATHLEN];
72 /* Save the starting point. */
73 getcwd(start,MAXPATHLEN);
74 if ((fd = open(".", O_RDONLY)) < 0) {
75 (void)strlcpy(resolved, ".", MAXPATHLEN);
80 /* Convert "." -> "" to optimize away a needless lstat() and chdir() */
81 if (path[0] == '.' && path[1] == '\0')
85 * Find the dirname and basename from the path to be resolved.
86 * Change directory to the dirname component.
87 * lstat the basename part.
88 * if it is a symlink, read in the value and loop.
89 * if it is a directory, then change to that directory.
90 * get the current directory name and append the basename.
92 strlcpy(resolved, path, MAXPATHLEN);
94 q = strrchr(resolved, '/');
102 } while (q > resolved && *q == '/');
111 /* Deal with the last component. */
112 if (*p != '\0' && lstat(p, &sb) == 0) {
113 if (S_ISLNK(sb.st_mode)) {
114 if (++symlinks > MAXSYMLINKS) {
118 n = readlink(p, resolved, MAXPATHLEN-1);
124 if (S_ISDIR(sb.st_mode)) {
132 * Save the last component name and get the full pathname of
133 * the current directory.
135 (void)strlcpy(wbuf, p, sizeof wbuf);
136 if (getcwd(resolved, MAXPATHLEN) == 0)
140 * Join the two strings together, ensuring that the right thing
141 * happens if the last component is empty, or the dirname is root.
143 if (resolved[0] == '/' && resolved[1] == '\0')
149 if (strlen(resolved) + strlen(wbuf) + needslash >= MAXPATHLEN) {
150 serrno = ENAMETOOLONG;
154 strlcat(resolved, "/", MAXPATHLEN);
155 strlcat(resolved, wbuf, MAXPATHLEN);
158 /* Go back to where we came from. */
159 if (chdir(start) < 0) {
166 err2: errno = serrno;
169 #endif /* !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH) */