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32 #if !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH)
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char *rcsid = "$OpenBSD: realpath..c,v 1.4 1998/05/18 09:55:19 deraadt Exp $";
36 #endif /* LIBC_SCCS and not lint */
38 #include <sys/param.h>
55 * char *realpath(const char *path, char resolved_path[MAXPATHLEN]);
57 * Find the real name of path, by removing all ".", ".." and symlink
58 * components. Returns (resolved) on success, or (NULL) on failure,
59 * in which case the path which caused trouble is left in (resolved).
62 realpath(const char *path, char *resolved)
65 int fd, n, rootd, serrno = 0;
66 char *p, *q, wbuf[MAXPATHLEN], start[MAXPATHLEN];
69 /* Save the starting point. */
70 getcwd(start,MAXPATHLEN);
71 if ((fd = open(".", O_RDONLY)) < 0) {
72 (void)strcpy(resolved, ".");
78 * Find the dirname and basename from the path to be resolved.
79 * Change directory to the dirname component.
80 * lstat the basename part.
81 * if it is a symlink, read in the value and loop.
82 * if it is a directory, then change to that directory.
83 * get the current directory name and append the basename.
85 (void)strncpy(resolved, path, MAXPATHLEN - 1);
86 resolved[MAXPATHLEN - 1] = '\0';
88 q = strrchr(resolved, '/');
96 } while (q > resolved && *q == '/');
105 /* Deal with the last component. */
106 if (lstat(p, &sb) == 0) {
107 if (S_ISLNK(sb.st_mode)) {
108 if (++symlinks > MAXSYMLINKS) {
112 n = readlink(p, resolved, MAXPATHLEN-1);
118 if (S_ISDIR(sb.st_mode)) {
126 * Save the last component name and get the full pathname of
127 * the current directory.
129 (void)strcpy(wbuf, p);
130 if (getcwd(resolved, MAXPATHLEN) == 0)
134 * Join the two strings together, ensuring that the right thing
135 * happens if the last component is empty, or the dirname is root.
137 if (resolved[0] == '/' && resolved[1] == '\0')
143 if (strlen(resolved) + strlen(wbuf) + rootd + 1 > MAXPATHLEN) {
144 serrno = ENAMETOOLONG;
148 (void)strcat(resolved, "/");
149 (void)strcat(resolved, wbuf);
152 /* Go back to where we came from. */
153 if (chdir(start) < 0) {
160 err2: errno = serrno;
163 #endif /* !defined(HAVE_REALPATH) || defined(BROKEN_REALPATH) */