*/
static
char *
-bsd_realpath(const char *path, char *resolved)
+bsd_realpath(const char *path, char resolved[MAXPATHLEN])
{
#ifdef VMS
dTHX;
return Perl_rmsexpand(aTHX_ (char*)path, resolved, NULL, 0);
#else
- int rootd, serrno;
- const char *p;
- char *q, wbuf[MAXPATHLEN];
- int symlinks = 0;
-
- /* Save the starting point. */
-#ifdef HAS_FCHDIR
- int fd;
-
- if ((fd = open(".", O_RDONLY)) < 0) {
- (void)strcpy(resolved, ".");
+ char *p, *q, *s;
+ size_t left_len, resolved_len;
+ unsigned symlinks;
+ int serrno;
+ char left[MAXPATHLEN], next_token[MAXPATHLEN], symlink[MAXPATHLEN];
+
+ serrno = errno;
+ symlinks = 0;
+ if (path[0] == '/') {
+ resolved[0] = '/';
+ resolved[1] = '\0';
+ if (path[1] == '\0')
+ return (resolved);
+ resolved_len = 1;
+ left_len = my_strlcpy(left, path + 1, sizeof(left));
+ } else {
+ if (getcwd(resolved, MAXPATHLEN) == NULL) {
+ my_strlcpy(resolved, ".", MAXPATHLEN);
return (NULL);
}
-#else
- char wd[MAXPATHLEN];
-
- if (getcwd(wd, MAXPATHLEN - 1) == NULL) {
- (void)strcpy(resolved, ".");
+ resolved_len = strlen(resolved);
+ left_len = my_strlcpy(left, path, sizeof(left));
+ }
+ if (left_len >= sizeof(left) || resolved_len >= MAXPATHLEN) {
+ errno = ENAMETOOLONG;
return (NULL);
}
-#endif
/*
- * 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.
+ * Iterate over path components in `left'.
*/
- (void)strncpy(resolved, path, MAXPATHLEN - 1);
- resolved[MAXPATHLEN - 1] = '\0';
-loop:
- q = strrchr(resolved, '/');
- if (q != NULL) {
- const char *dir;
- p = q + 1;
- if (q == resolved)
- dir = "/";
- else {
- do {
- --q;
- } while (q > resolved && *q == '/');
- q[1] = '\0';
- dir = resolved;
- }
- if (chdir(dir) < 0)
- goto err1;
- } else
- p = resolved;
-
-#if defined(HAS_LSTAT) && defined(HAS_READLINK) && defined(HAS_SYMLINK)
- {
- struct stat sb;
- /* Deal with the last component. */
- if (lstat(p, &sb) == 0) {
- if (S_ISLNK(sb.st_mode)) {
- int n;
- if (++symlinks > MAXSYMLINKS) {
- errno = ELOOP;
- goto err1;
+ 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);
}
- 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 = "";
+ 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 >= MAXPATHLEN) {
+ 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;
}
-#endif
/*
- * Save the last component name and get the full pathname of
- * the current directory.
+ * Append the next path component and lstat() it. If
+ * lstat() fails we still can return successfully if
+ * there are no more path components left.
*/
- (void)strcpy(wbuf, p);
- if (getcwd(resolved, MAXPATHLEN) == 0)
- goto err1;
+ resolved_len = my_strlcat(resolved, next_token, MAXPATHLEN);
+ if (resolved_len >= MAXPATHLEN) {
+ errno = ENAMETOOLONG;
+ return (NULL);
+ }
+ #if defined(HAS_LSTAT) && defined(HAS_READLINK) && defined(HAS_SYMLINK)
+ {
+ struct stat sb;
+ if (lstat(resolved, &sb) != 0) {
+ if (errno == ENOENT && p == NULL) {
+ errno = serrno;
+ return (resolved);
+ }
+ return (NULL);
+ }
+ if (S_ISLNK(sb.st_mode)) {
+ int slen;
+
+ 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;
+ }
/*
- * Join the two strings together, ensuring that the right thing
- * happens if the last component is empty, or the dirname is root.
+ * If there are any path components left, then
+ * append them to symlink. The result is placed
+ * in `left'.
*/
- if (resolved[0] == '/' && resolved[1] == '\0')
- rootd = 1;
- else
- rootd = 0;
-
- if (*wbuf) {
- if (strlen(resolved) + strlen(wbuf) + (1 - rootd) + 1 > MAXPATHLEN) {
+ if (p != NULL) {
+ if (symlink[slen - 1] != '/') {
+ if (slen + 1 >= sizeof(symlink)) {
errno = ENAMETOOLONG;
- goto err1;
+ return (NULL);
}
- if (rootd == 0)
- (void)strcat(resolved, "/");
- (void)strcat(resolved, wbuf);
+ symlink[slen] = '/';
+ symlink[slen + 1] = 0;
}
-
- /* Go back to where we came from. */
-#ifdef HAS_FCHDIR
- if (fchdir(fd) < 0) {
- serrno = errno;
- goto err2;
+ left_len = my_strlcat(symlink, left, sizeof(left));
+ if (left_len >= sizeof(left)) {
+ errno = ENAMETOOLONG;
+ return (NULL);
}
-#else
- if (chdir(wd) < 0) {
- serrno = errno;
- goto err2;
}
-#endif
+ left_len = my_strlcpy(left, symlink, sizeof(left));
+ }
+ }
+ #endif
+ }
- /* It's okay if the close fails, what's an fd more or less? */
-#ifdef HAS_FCHDIR
- (void)close(fd);
-#endif
+ /*
+ * Remove trailing slash except when the resolved pathname
+ * is a single "/".
+ */
+ if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
+ resolved[resolved_len - 1] = '\0';
return (resolved);
-
-err1: serrno = errno;
-#ifdef HAS_FCHDIR
- (void)fchdir(fd);
-#else
- (void)chdir(wd);
-#endif
-
-err2:
-#ifdef HAS_FCHDIR
- (void)close(fd);
-#endif
- errno = serrno;
- return (NULL);
#endif
}
projects / p5sagit/p5-mst-13.2.git / commitdiff