/* File tree traversal functions.
Copyright (C) 1994-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/*-
* Copyright (c) 1990, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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 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)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
#endif /* LIBC_SCCS and not lint */
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <sys/param.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <errno.h>
#include "priv_fts.h"
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define FTS_OPEN _priv_fts_open
#define FTS_CLOSE _priv_fts_close
#define FTS_READ _priv_fts_read
#define FTS_SET _priv_fts_set
#define FTS_CHILDREN _priv_fts_children
#define FTSOBJ FTS
#define FTSENTRY FTSENT
#define INO_T ino_t
#define STAT stat
#define LSTAT lstat
#define internal_function
#define __set_errno(val) (errno = (val))
/* Largest alignment size needed, minus one.
Usually long double is the worst case. */
#ifndef ALIGNBYTES
#define ALIGNBYTES (__alignof__(long double) - 1)
#endif
/* Align P to that size. */
#ifndef ALIGN
#define ALIGN(p) (((unsigned long int)(p) + ALIGNBYTES) & ~ALIGNBYTES)
#endif
/* Support for the LFS API version. */
#ifndef FTS_OPEN
#define FTS_OPEN fts_open
#define FTS_CLOSE fts_close
#define FTS_READ fts_read
#define FTS_SET fts_set
#define FTS_CHILDREN fts_children
#define FTSOBJ FTS
#define FTSENTRY FTSENT
#define INO_T ino_t
#define STAT stat
#define LSTAT lstat
#endif
static FTSENTRY *fts_alloc(FTSOBJ *, const char *, size_t) internal_function;
static FTSENTRY *fts_build(FTSOBJ *, int) internal_function;
static void fts_lfree(FTSENTRY *) internal_function;
static void fts_load(FTSOBJ *, FTSENTRY *) internal_function;
static size_t fts_maxarglen(char *const *) internal_function;
static void fts_padjust(FTSOBJ *, FTSENTRY *) internal_function;
static int fts_palloc(FTSOBJ *, size_t) internal_function;
static FTSENTRY *fts_sort(FTSOBJ *, FTSENTRY *, int) internal_function;
static u_short fts_stat(FTSOBJ *, FTSENTRY *, int) internal_function;
static int fts_safe_changedir(FTSOBJ *, FTSENTRY *, int, const char *)
internal_function;
#ifndef MAX
#define MAX(a, b) ({ __typeof__ (a) _a = (a); \
__typeof__ (b) _b = (b); \
_a > _b ? _a : _b; })
#endif
#define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
#define CLR(opt) (sp->fts_options &= ~(opt))
#define ISSET(opt) (sp->fts_options & (opt))
#define SET(opt) (sp->fts_options |= (opt))
#define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd))
/* fts_build flags */
#define BCHILD 1 /* fts_children */
#define BNAMES 2 /* fts_children, names only */
#define BREAD 3 /* fts_read */
FTSOBJ *
FTS_OPEN(char *const *argv, int options,
int (*compar)(const FTSENTRY **, const FTSENTRY **))
{
FTSOBJ *sp;
FTSENTRY *p, *root;
int nitems;
FTSENTRY *parent = NULL;
FTSENTRY *tmp;
/* Options check. */
if (options & ~FTS_OPTIONMASK) {
__set_errno(EINVAL);
return (NULL);
}
/* Allocate/initialize the stream */
if ((sp = malloc((u_int)sizeof(FTSOBJ))) == NULL)
return (NULL);
memset(sp, 0, sizeof(FTSOBJ));
sp->fts_compar = (int (*)(const void *, const void *))compar;
sp->fts_options = options;
/* Logical walks turn on NOCHDIR; symbolic links are too hard. */
if (ISSET(FTS_LOGICAL))
SET(FTS_NOCHDIR);
/*
* Start out with 1K of path space, and enough, in any case,
* to hold the user's paths.
*/
#ifndef MAXPATHLEN
#define MAXPATHLEN 1024
#endif
size_t maxarglen = fts_maxarglen(argv);
if (fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
goto mem1;
/* Allocate/initialize root's parent. */
if (*argv != NULL) {
if ((parent = fts_alloc(sp, "", 0)) == NULL)
goto mem2;
parent->fts_level = FTS_ROOTPARENTLEVEL;
}
/* Allocate/initialize root(s). */
for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
/* Don't allow zero-length paths. */
size_t len = strlen(*argv);
if (len == 0) {
__set_errno(ENOENT);
goto mem3;
}
p = fts_alloc(sp, *argv, len);
p->fts_level = FTS_ROOTLEVEL;
p->fts_parent = parent;
p->fts_accpath = p->fts_name;
p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW));
/* Command-line "." and ".." are real directories. */
if (p->fts_info == FTS_DOT)
p->fts_info = FTS_D;
/*
* If comparison routine supplied, traverse in sorted
* order; otherwise traverse in the order specified.
*/
if (compar) {
p->fts_link = root;
root = p;
} else {
p->fts_link = NULL;
if (root == NULL)
tmp = root = p;
else {
tmp->fts_link = p;
tmp = p;
}
}
}
if (compar && nitems > 1)
root = fts_sort(sp, root, nitems);
/*
* Allocate a dummy pointer and make fts_read think that we've just
* finished the node before the root(s); set p->fts_info to FTS_INIT
* so that everything about the "current" node is ignored.
*/
if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
goto mem3;
sp->fts_cur->fts_link = root;
sp->fts_cur->fts_info = FTS_INIT;
/*
* If using chdir(2), grab a file descriptor pointing to dot to ensure
* that we can get back here; this could be avoided for some paths,
* but almost certainly not worth the effort. Slashes, symbolic links,
* and ".." are all fairly nasty problems. Note, if we can't get the
* descriptor we run anyway, just more slowly.
*/
if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0)
SET(FTS_NOCHDIR);
return (sp);
mem3:
fts_lfree(root);
free(parent);
mem2:
free(sp->fts_path);
mem1:
free(sp);
return (NULL);
}
static void
internal_function
fts_load(FTSOBJ *sp, FTSENTRY *p)
{
int len;
char *cp;
/*
* Load the stream structure for the next traversal. Since we don't
* actually enter the directory until after the preorder visit, set
* the fts_accpath field specially so the chdir gets done to the right
* place and the user can access the first node. From fts_open it's
* known that the path will fit.
*/
len = p->fts_pathlen = p->fts_namelen;
memmove(sp->fts_path, p->fts_name, len + 1);
if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
len = strlen(++cp);
memmove(p->fts_name, cp, len + 1);
p->fts_namelen = len;
}
p->fts_accpath = p->fts_path = sp->fts_path;
sp->fts_dev = p->fts_dev;
}
int FTS_CLOSE(FTSOBJ *sp)
{
FTSENTRY *freep, *p;
int saved_errno;
/*
* This still works if we haven't read anything -- the dummy structure
* points to the root list, so we step through to the end of the root
* list which has a valid parent pointer.
*/
if (sp->fts_cur) {
for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
freep = p;
p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
free(freep);
}
free(p);
}
/* Free up child linked list, sort array, path buffer. */
if (sp->fts_child)
fts_lfree(sp->fts_child);
free(sp->fts_array);
free(sp->fts_path);
/* Return to original directory, save errno if necessary. */
if (!ISSET(FTS_NOCHDIR)) {
saved_errno = fchdir(sp->fts_rfd) ? errno : 0;
(void)close(sp->fts_rfd);
/* Set errno and return. */
if (saved_errno != 0) {
/* Free up the stream pointer. */
free(sp);
__set_errno(saved_errno);
return (-1);
}
}
/* Free up the stream pointer. */
free(sp);
return (0);
}
/*
* Special case of "/" at the end of the path so that slashes aren't
* appended which would cause paths to be written as "....//foo".
*/
#define NAPPEND(p) \
(p->fts_path[p->fts_pathlen - 1] == '/' \
? p->fts_pathlen - 1 \
: p->fts_pathlen)
FTSENTRY *
FTS_READ(FTSOBJ *sp)
{
FTSENTRY *p, *tmp;
int instr;
char *t;
int saved_errno;
/* If finished or unrecoverable error, return NULL. */
if (sp->fts_cur == NULL || ISSET(FTS_STOP))
return (NULL);
/* Set current node pointer. */
p = sp->fts_cur;
/* Save and zero out user instructions. */
instr = p->fts_instr;
p->fts_instr = FTS_NOINSTR;
/* Any type of file may be re-visited; re-stat and re-turn. */
if (instr == FTS_AGAIN) {
p->fts_info = fts_stat(sp, p, 0);
return (p);
}
/*
* Following a symlink -- SLNONE test allows application to see
* SLNONE and recover. If indirecting through a symlink, have
* keep a pointer to current location. If unable to get that
* pointer, follow fails.
*/
if (instr == FTS_FOLLOW &&
(p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
p->fts_info = fts_stat(sp, p, 1);
if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) {
p->fts_errno = errno;
p->fts_info = FTS_ERR;
} else
p->fts_flags |= FTS_SYMFOLLOW;
}
return (p);
}
/* Directory in pre-order. */
if (p->fts_info == FTS_D) {
/* If skipped or crossed mount point, do post-order visit. */
if (instr == FTS_SKIP ||
(ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) {
if (p->fts_flags & FTS_SYMFOLLOW)
(void)close(p->fts_symfd);
if (sp->fts_child) {
fts_lfree(sp->fts_child);
sp->fts_child = NULL;
}
p->fts_info = FTS_DP;
return (p);
}
/* Rebuild if only read the names and now traversing. */
if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
CLR(FTS_NAMEONLY);
fts_lfree(sp->fts_child);
sp->fts_child = NULL;
}
/*
* Cd to the subdirectory.
*
* If have already read and now fail to chdir, whack the list
* to make the names come out right, and set the parent errno
* so the application will eventually get an error condition.
* Set the FTS_DONTCHDIR flag so that when we logically change
* directories back to the parent we don't do a chdir.
*
* If haven't read do so. If the read fails, fts_build sets
* FTS_STOP or the fts_info field of the node.
*/
if (sp->fts_child != NULL) {
if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
p->fts_errno = errno;
p->fts_flags |= FTS_DONTCHDIR;
for (p = sp->fts_child; p != NULL;
p = p->fts_link)
p->fts_accpath =
p->fts_parent->fts_accpath;
}
} else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
if (ISSET(FTS_STOP))
return (NULL);
return (p);
}
p = sp->fts_child;
sp->fts_child = NULL;
sp->fts_cur = p;
goto name;
}
/* Move to the next node on this level. */
next:
tmp = p;
if ((p = p->fts_link) != NULL) {
sp->fts_cur = p;
free(tmp);
/*
* If reached the top, return to the original directory (or
* the root of the tree), and load the paths for the next root.
*/
if (p->fts_level == FTS_ROOTLEVEL) {
if (FCHDIR(sp, sp->fts_rfd)) {
SET(FTS_STOP);
return (NULL);
}
fts_load(sp, p);
return p;
}
/*
* User may have called fts_set on the node. If skipped,
* ignore. If followed, get a file descriptor so we can
* get back if necessary.
*/
if (p->fts_instr == FTS_SKIP)
goto next;
if (p->fts_instr == FTS_FOLLOW) {
p->fts_info = fts_stat(sp, p, 1);
if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
if ((p->fts_symfd =
open(".", O_RDONLY, 0)) < 0) {
p->fts_errno = errno;
p->fts_info = FTS_ERR;
} else
p->fts_flags |= FTS_SYMFOLLOW;
}
p->fts_instr = FTS_NOINSTR;
}
name:
t = sp->fts_path + NAPPEND(p->fts_parent);
*t++ = '/';
memmove(t, p->fts_name, p->fts_namelen + 1);
return p;
}
/* Move up to the parent node. */
p = tmp->fts_parent;
sp->fts_cur = p;
free(tmp);
if (p->fts_level == FTS_ROOTPARENTLEVEL) {
/*
* Done; free everything up and set errno to 0 so the user
* can distinguish between error and EOF.
*/
free(p);
__set_errno(0);
return (sp->fts_cur = NULL);
}
/* NUL terminate the pathname. */
sp->fts_path[p->fts_pathlen] = '\0';
/*
* Return to the parent directory. If at a root node or came through
* a symlink, go back through the file descriptor. Otherwise, cd up
* one directory.
*/
if (p->fts_level == FTS_ROOTLEVEL) {
if (FCHDIR(sp, sp->fts_rfd)) {
SET(FTS_STOP);
return (NULL);
}
} else if (p->fts_flags & FTS_SYMFOLLOW) {
if (FCHDIR(sp, p->fts_symfd)) {
saved_errno = errno;
(void)close(p->fts_symfd);
__set_errno(saved_errno);
SET(FTS_STOP);
return (NULL);
}
(void)close(p->fts_symfd);
} else if (!(p->fts_flags & FTS_DONTCHDIR) &&
fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
SET(FTS_STOP);
return (NULL);
}
p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
return p;
}
/*
* Fts_set takes the stream as an argument although it's not used in this
* implementation; it would be necessary if anyone wanted to add global
* semantics to fts using fts_set. An error return is allowed for similar
* reasons.
*/
/* ARGSUSED */
int FTS_SET(FTSOBJ *sp, FTSENTRY *p, int instr)
{
if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
instr != FTS_NOINSTR && instr != FTS_SKIP) {
__set_errno(EINVAL);
return (1);
}
p->fts_instr = instr;
return (0);
}
FTSENTRY *
FTS_CHILDREN(FTSOBJ *sp, int instr)
{
FTSENTRY *p;
int fd;
if (instr != 0 && instr != FTS_NAMEONLY) {
__set_errno(EINVAL);
return (NULL);
}
/* Set current node pointer. */
p = sp->fts_cur;
/*
* Errno set to 0 so user can distinguish empty directory from
* an error.
*/
__set_errno(0);
/* Fatal errors stop here. */
if (ISSET(FTS_STOP))
return (NULL);
/* Return logical hierarchy of user's arguments. */
if (p->fts_info == FTS_INIT)
return (p->fts_link);
/*
* If not a directory being visited in pre-order, stop here. Could
* allow FTS_DNR, assuming the user has fixed the problem, but the
* same effect is available with FTS_AGAIN.
*/
if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
return (NULL);
/* Free up any previous child list. */
if (sp->fts_child != NULL)
fts_lfree(sp->fts_child);
if (instr == FTS_NAMEONLY) {
SET(FTS_NAMEONLY);
instr = BNAMES;
} else
instr = BCHILD;
/*
* If using chdir on a relative path and called BEFORE fts_read does
* its chdir to the root of a traversal, we can lose -- we need to
* chdir into the subdirectory, and we don't know where the current
* directory is, so we can't get back so that the upcoming chdir by
* fts_read will work.
*/
if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
ISSET(FTS_NOCHDIR))
return (sp->fts_child = fts_build(sp, instr));
if ((fd = open(".", O_RDONLY, 0)) < 0)
return (NULL);
sp->fts_child = fts_build(sp, instr);
if (fchdir(fd))
return (NULL);
(void)close(fd);
return (sp->fts_child);
}
static inline int
dirent_not_directory(const struct dirent *dp)
{
#if defined DT_DIR && defined _DIRENT_HAVE_D_TYPE
return dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN;
#else
return 0;
#endif
}
/*
* This is the tricky part -- do not casually change *anything* in here. The
* idea is to build the linked list of entries that are used by fts_children
* and fts_read. There are lots of special cases.
*
* The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
* set and it's a physical walk (so that symbolic links can't be directories),
* we can do things quickly. First, if it's a 4.4BSD file system, the type
* of the file is in the directory entry. Otherwise, we assume that the number
* of subdirectories in a node is equal to the number of links to the parent.
* The former skips all stat calls. The latter skips stat calls in any leaf
* directories and for any files after the subdirectories in the directory have
* been found, cutting the stat calls by about 2/3.
*/
static FTSENTRY *
internal_function
fts_build(FTSOBJ *sp, int type)
{
struct dirent *dp;
FTSENTRY *p, *head;
int nitems;
FTSENTRY *cur, *tail;
DIR *dirp;
void *oldaddr;
int cderrno, descend, len, level, nlinks, saved_errno,
nostat, doadjust;
size_t maxlen;
char *cp;
/* Set current node pointer. */
cur = sp->fts_cur;
/*
* Open the directory for reading. If this fails, we're done.
* If being called from fts_read, set the fts_info field.
*/
#if defined FTS_WHITEOUT && 0
if (ISSET(FTS_WHITEOUT))
oflag = DTF_NODUP | DTF_REWIND;
else
oflag = DTF_HIDEW | DTF_NODUP | DTF_REWIND;
#else
#define __opendir2(path, flag) opendir(path)
#endif
if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
if (type == BREAD) {
cur->fts_info = FTS_DNR;
cur->fts_errno = errno;
}
return (NULL);
}
/*
* Nlinks is the number of possible entries of type directory in the
* directory if we're cheating on stat calls, 0 if we're not doing
* any stat calls at all, -1 if we're doing stats on everything.
*/
if (type == BNAMES) {
nlinks = 0;
/* Be quiet about nostat, GCC. */
nostat = 0;
} else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);
nostat = 1;
} else {
nlinks = -1;
nostat = 0;
}
#ifdef notdef
(void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink);
(void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n",
ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT));
#endif
/*
* If we're going to need to stat anything or we want to descend
* and stay in the directory, chdir. If this fails we keep going,
* but set a flag so we don't chdir after the post-order visit.
* We won't be able to stat anything, but we can still return the
* names themselves. Note, that since fts_read won't be able to
* chdir into the directory, it will have to return different path
* names than before, i.e. "a/b" instead of "b". Since the node
* has already been visited in pre-order, have to wait until the
* post-order visit to return the error. There is a special case
* here, if there was nothing to stat then it's not an error to
* not be able to stat. This is all fairly nasty. If a program
* needed sorted entries or stat information, they had better be
* checking FTS_NS on the returned nodes.
*/
cderrno = 0;
if (nlinks || type == BREAD) {
if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) {
if (nlinks && type == BREAD)
cur->fts_errno = errno;
cur->fts_flags |= FTS_DONTCHDIR;
descend = 0;
cderrno = errno;
(void)closedir(dirp);
dirp = NULL;
} else
descend = 1;
} else
descend = 0;
/*
* Figure out the max file name length that can be stored in the
* current path -- the inner loop allocates more path as necessary.
* We really wouldn't have to do the maxlen calculations here, we
* could do them in fts_read before returning the path, but it's a
* lot easier here since the length is part of the dirent structure.
*
* If not changing directories set a pointer so that can just append
* each new name into the path.
*/
len = NAPPEND(cur);
if (ISSET(FTS_NOCHDIR)) {
cp = sp->fts_path + len;
*cp++ = '/';
} else {
/* GCC, you're too verbose. */
cp = NULL;
}
len++;
maxlen = sp->fts_pathlen - len;
level = cur->fts_level + 1;
/* Read the directory, attaching each entry to the `link' pointer. */
doadjust = 0;
for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
continue;
if ((p = fts_alloc(sp, dp->d_name, _D_EXACT_NAMLEN(dp))) == NULL)
goto mem1;
if (_D_EXACT_NAMLEN(dp) >= maxlen) { /* include space for NUL */
oldaddr = sp->fts_path;
if (fts_palloc(sp, _D_EXACT_NAMLEN(dp) + len + 1)) {
/*
* No more memory for path or structures. Save
* errno, free up the current structure and the
* structures already allocated.
*/
mem1:
saved_errno = errno;
free(p);
fts_lfree(head);
(void)closedir(dirp);
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
__set_errno(saved_errno);
return (NULL);
}
/* Did realloc() change the pointer? */
if (oldaddr != sp->fts_path) {
doadjust = 1;
if (ISSET(FTS_NOCHDIR))
cp = sp->fts_path + len;
}
maxlen = sp->fts_pathlen - len;
}
if (len + _D_EXACT_NAMLEN(dp) >= USHRT_MAX) {
/*
* In an FTSENT, fts_pathlen is a u_short so it is
* possible to wraparound here. If we do, free up
* the current structure and the structures already
* allocated, then error out with ENAMETOOLONG.
*/
free(p);
fts_lfree(head);
(void)closedir(dirp);
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
__set_errno(ENAMETOOLONG);
return (NULL);
}
p->fts_level = level;
p->fts_parent = sp->fts_cur;
p->fts_pathlen = len + _D_EXACT_NAMLEN(dp);
#if defined FTS_WHITEOUT && 0
if (dp->d_type == DT_WHT)
p->fts_flags |= FTS_ISW;
#endif
/* Unreachable code. cderrno is only ever set to a nonnull
value if dirp is closed at the same time. But then we
cannot enter this loop. */
if (0 && cderrno) {
if (nlinks) {
p->fts_info = FTS_NS;
p->fts_errno = cderrno;
} else
p->fts_info = FTS_NSOK;
p->fts_accpath = cur->fts_accpath;
} else if (nlinks == 0 || (nostat && dirent_not_directory(dp))) {
p->fts_accpath =
ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name;
p->fts_info = FTS_NSOK;
} else {
/* Build a file name for fts_stat to stat. */
if (ISSET(FTS_NOCHDIR)) {
p->fts_accpath = p->fts_path;
memmove(cp, p->fts_name, p->fts_namelen + 1);
} else
p->fts_accpath = p->fts_name;
/* Stat it. */
p->fts_info = fts_stat(sp, p, 0);
/* Decrement link count if applicable. */
if (nlinks > 0 && (p->fts_info == FTS_D ||
p->fts_info == FTS_DC || p->fts_info == FTS_DOT))
--nlinks;
}
/* We walk in directory order so "ls -f" doesn't get upset. */
p->fts_link = NULL;
if (head == NULL)
head = tail = p;
else {
tail->fts_link = p;
tail = p;
}
++nitems;
}
if (dirp)
(void)closedir(dirp);
/*
* If realloc() changed the address of the path, adjust the
* addresses for the rest of the tree and the dir list.
*/
if (doadjust)
fts_padjust(sp, head);
/*
* If not changing directories, reset the path back to original
* state.
*/
if (ISSET(FTS_NOCHDIR)) {
if (len == sp->fts_pathlen || nitems == 0)
--cp;
*cp = '\0';
}
/*
* If descended after called from fts_children or after called from
* fts_read and nothing found, get back. At the root level we use
* the saved fd; if one of fts_open()'s arguments is a relative path
* to an empty directory, we wind up here with no other way back. If
* can't get back, we're done.
*/
if (descend && (type == BCHILD || !nitems) &&
(cur->fts_level == FTS_ROOTLEVEL ? FCHDIR(sp, sp->fts_rfd) : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
fts_lfree(head);
return (NULL);
}
/* If didn't find anything, return NULL. */
if (!nitems) {
if (type == BREAD)
cur->fts_info = FTS_DP;
fts_lfree(head);
return (NULL);
}
/* Sort the entries. */
if (sp->fts_compar && nitems > 1)
head = fts_sort(sp, head, nitems);
return (head);
}
static u_short
internal_function
fts_stat(FTSOBJ *sp, FTSENTRY *p, int follow)
{
FTSENTRY *t;
dev_t dev;
INO_T ino;
struct STAT *sbp, sb;
int saved_errno;
/* If user needs stat info, stat buffer already allocated. */
sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp;
#if defined FTS_WHITEOUT && 0
/* check for whiteout */
if (p->fts_flags & FTS_ISW) {
if (sbp != &sb) {
memset(sbp, '\0', sizeof(*sbp));
sbp->st_mode = S_IFWHT;
}
return (FTS_W);
}
#endif
/*
* If doing a logical walk, or application requested FTS_FOLLOW, do
* a stat(2). If that fails, check for a non-existent symlink. If
* fail, set the errno from the stat call.
*/
if (ISSET(FTS_LOGICAL) || follow) {
if (STAT(p->fts_accpath, sbp)) {
saved_errno = errno;
if (!LSTAT(p->fts_accpath, sbp)) {
__set_errno(0);
return (FTS_SLNONE);
}
p->fts_errno = saved_errno;
goto err;
}
} else if (LSTAT(p->fts_accpath, sbp)) {
p->fts_errno = errno;
err:
memset(sbp, 0, sizeof(struct STAT));
return (FTS_NS);
}
if (S_ISDIR(sbp->st_mode)) {
/*
* Set the device/inode. Used to find cycles and check for
* crossing mount points. Also remember the link count, used
* in fts_build to limit the number of stat calls. It is
* understood that these fields are only referenced if fts_info
* is set to FTS_D.
*/
dev = p->fts_dev = sbp->st_dev;
ino = p->fts_ino = sbp->st_ino;
p->fts_nlink = sbp->st_nlink;
if (ISDOT(p->fts_name))
return (FTS_DOT);
/*
* Cycle detection is done by brute force when the directory
* is first encountered. If the tree gets deep enough or the
* number of symbolic links to directories is high enough,
* something faster might be worthwhile.
*/
for (t = p->fts_parent;
t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
if (ino == t->fts_ino && dev == t->fts_dev) {
p->fts_cycle = t;
return (FTS_DC);
}
return (FTS_D);
}
if (S_ISLNK(sbp->st_mode))
return (FTS_SL);
if (S_ISREG(sbp->st_mode))
return (FTS_F);
return (FTS_DEFAULT);
}
static FTSENTRY *
internal_function
fts_sort(FTSOBJ *sp, FTSENTRY *head, int nitems)
{
FTSENTRY **ap, *p;
/*
* Construct an array of pointers to the structures and call qsort(3).
* Reassemble the array in the order returned by qsort. If unable to
* sort for memory reasons, return the directory entries in their
* current order. Allocate enough space for the current needs plus
* 40 so don't realloc one entry at a time.
*/
if (nitems > sp->fts_nitems) {
FTSENTRY **a;
sp->fts_nitems = nitems + 40;
if ((a = realloc(sp->fts_array,
(size_t)(sp->fts_nitems * sizeof(FTSENTRY *)))) == NULL) {
free(sp->fts_array);
sp->fts_array = NULL;
sp->fts_nitems = 0;
return (head);
}
sp->fts_array = a;
}
for (ap = sp->fts_array, p = head; p; p = p->fts_link)
*ap++ = p;
qsort((void *)sp->fts_array, nitems, sizeof(FTSENTRY *), sp->fts_compar);
for (head = *(ap = sp->fts_array); --nitems; ++ap)
ap[0]->fts_link = ap[1];
ap[0]->fts_link = NULL;
return (head);
}
static FTSENTRY *
internal_function
fts_alloc(FTSOBJ *sp, const char *name, size_t namelen)
{
FTSENTRY *p;
size_t len;
/*
* The file name is a variable length array and no stat structure is
* necessary if the user has set the nostat bit. Allocate the FTSENT
* structure, the file name and the stat structure in one chunk, but
* be careful that the stat structure is reasonably aligned. Since the
* fts_name field is declared to be of size 1, the fts_name pointer is
* namelen + 2 before the first possible address of the stat structure.
*/
len = sizeof(FTSENTRY) + namelen;
if (!ISSET(FTS_NOSTAT))
len += sizeof(struct STAT) + ALIGNBYTES;
if ((p = malloc(len)) == NULL)
return (NULL);
/* Copy the name and guarantee NUL termination. */
memmove(p->fts_name, name, namelen);
p->fts_name[namelen] = '\0';
if (!ISSET(FTS_NOSTAT))
p->fts_statp = (struct STAT *)ALIGN(p->fts_name + namelen + 2);
p->fts_namelen = namelen;
p->fts_path = sp->fts_path;
p->fts_errno = 0;
p->fts_flags = 0;
p->fts_instr = FTS_NOINSTR;
p->fts_number = 0;
p->fts_pointer = NULL;
return (p);
}
static void
internal_function
fts_lfree(FTSENTRY *head)
{
FTSENTRY *p;
/* Free a linked list of structures. */
while ((p = head)) {
head = head->fts_link;
free(p);
}
}
/*
* Allow essentially unlimited paths; find, rm, ls should all work on any tree.
* Most systems will allow creation of paths much longer than MAXPATHLEN, even
* though the kernel won't resolve them. Add the size (not just what's needed)
* plus 256 bytes so don't realloc the path 2 bytes at a time.
*/
static int
internal_function
fts_palloc(FTSOBJ *sp, size_t more)
{
char *p;
sp->fts_pathlen += more + 256;
/*
* Check for possible wraparound. In an FTS, fts_pathlen is
* a signed int but in an FTSENT it is an unsigned short.
* We limit fts_pathlen to USHRT_MAX to be safe in both cases.
*/
if (sp->fts_pathlen < 0 || sp->fts_pathlen >= USHRT_MAX) {
free(sp->fts_path);
sp->fts_path = NULL;
__set_errno(ENAMETOOLONG);
return (1);
}
p = realloc(sp->fts_path, sp->fts_pathlen);
if (p == NULL) {
free(sp->fts_path);
sp->fts_path = NULL;
return 1;
}
sp->fts_path = p;
return 0;
}
/*
* When the path is realloc'd, have to fix all of the pointers in structures
* already returned.
*/
static void
internal_function
fts_padjust(FTSOBJ *sp, FTSENTRY *head)
{
FTSENTRY *p;
char *addr = sp->fts_path;
#define ADJUST(p) \
do { \
if ((p)->fts_accpath != (p)->fts_name) { \
(p)->fts_accpath = \
(char *)addr + ((p)->fts_accpath - (p)->fts_path); \
} \
(p)->fts_path = addr; \
} while (0)
/* Adjust the current set of children. */
for (p = sp->fts_child; p; p = p->fts_link)
ADJUST(p);
/* Adjust the rest of the tree, including the current level. */
for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
ADJUST(p);
p = p->fts_link ? p->fts_link : p->fts_parent;
}
}
static size_t
internal_function
fts_maxarglen(char *const *argv)
{
size_t len, max;
for (max = 0; *argv; ++argv)
if ((len = strlen(*argv)) > max)
max = len;
return (max + 1);
}
/*
* Change to dir specified by fd or p->fts_accpath without getting
* tricked by someone changing the world out from underneath us.
* Assumes p->fts_dev and p->fts_ino are filled in.
*/
static int
internal_function
fts_safe_changedir(FTSOBJ *sp, FTSENTRY *p, int fd, const char *path)
{
int ret, oerrno, newfd;
struct stat sb;
newfd = fd;
if (ISSET(FTS_NOCHDIR))
return (0);
if (fd < 0 && (newfd = open(path, O_RDONLY, 0)) < 0)
return (-1);
if (fstat(newfd, &sb)) {
ret = -1;
goto bail;
}
if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {
__set_errno(ENOENT); /* disinformation */
ret = -1;
goto bail;
}
ret = fchdir(newfd);
bail:
oerrno = errno;
if (fd < 0)
(void)close(newfd);
__set_errno(oerrno);
return (ret);
}