glibc/io/fts.c
1995-02-18 01:27:10 +00:00

982 lines
26 KiB
C

/*-
* Copyright (c) 1990, 1993
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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 8.2 (Berkeley) 1/2/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <errno.h>
#include <fts.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/* 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
static FTSENT *fts_alloc __P((FTS *, char *, int));
static FTSENT *fts_build __P((FTS *, int));
static void fts_lfree __P((FTSENT *));
static void fts_load __P((FTS *, FTSENT *));
static size_t fts_maxarglen __P((char * const *));
static void fts_padjust __P((FTS *, void *));
static int fts_palloc __P((FTS *, size_t));
static FTSENT *fts_sort __P((FTS *, FTSENT *, int));
static u_short fts_stat __P((FTS *, FTSENT *, int));
#define ISDOT(a) (a[0] == '.' && (!a[1] || a[1] == '.' && !a[2]))
#define ISSET(opt) (sp->fts_options & opt)
#define SET(opt) (sp->fts_options |= opt)
#define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path))
#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 */
FTS *
fts_open(argv, options, compar)
char * const *argv;
register int options;
int (*compar)();
{
register FTS *sp;
register FTSENT *p, *root;
register int nitems;
FTSENT *parent, *tmp;
int len;
/* Options check. */
if (options & ~FTS_OPTIONMASK) {
errno = EINVAL;
return (NULL);
}
/* Allocate/initialize the stream */
if ((sp = malloc((u_int)sizeof(FTS))) == NULL)
return (NULL);
bzero(sp, sizeof(FTS));
sp->fts_compar = 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
if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN)))
goto mem1;
/* Allocate/initialize root's parent. */
if ((parent = fts_alloc(sp, "", 0)) == NULL)
goto mem2;
parent->fts_level = FTS_ROOTPARENTLEVEL;
/* Allocate/initialize root(s). */
for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) {
/* Don't allow zero-length paths. */
if ((len = strlen(*argv)) == 0) {
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 insure
* 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
fts_load(sp, p)
FTS *sp;
register FTSENT *p;
{
register int len;
register 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;
bcopy(p->fts_name, sp->fts_path, len + 1);
if ((cp = rindex(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
len = strlen(++cp);
bcopy(cp, p->fts_name, len + 1);
p->fts_namelen = len;
}
p->fts_accpath = p->fts_path = sp->fts_path;
sp->fts_dev = p->fts_dev;
}
int
fts_close(sp)
FTS *sp;
{
register FTSENT *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 ? 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);
if (sp->fts_array)
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);
}
/* Free up the stream pointer. */
free(sp);
/* Set errno and return. */
if (!ISSET(FTS_NOCHDIR) && saved_errno) {
errno = saved_errno;
return (-1);
}
return (0);
}
/*
* Special case a root of "/" so that slashes aren't appended which would
* cause paths to be written as "//foo".
*/
#define NAPPEND(p) \
(p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \
p->fts_path[0] == '/' ? 0 : p->fts_pathlen)
FTSENT *
fts_read(sp)
register FTS *sp;
{
register FTSENT *p, *tmp;
register int instr;
register 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 && sp->fts_options & FTS_NAMEONLY) {
sp->fts_options &= ~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) {
if (CHDIR(sp, p->fts_accpath)) {
p->fts_errno = errno;
p->fts_flags |= FTS_DONTCHDIR;
for (p = sp->fts_child; p; 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;
goto name;
}
/* Move to the next node on this level. */
next: tmp = p;
if (p = p->fts_link) {
free(tmp);
/*
* If reached the top, return to the original directory, and
* load the paths for the next root.
*/
if (p->fts_level == FTS_ROOTLEVEL) {
if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) {
SET(FTS_STOP);
return (NULL);
}
fts_load(sp, p);
return (sp->fts_cur = 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++ = '/';
bcopy(p->fts_name, t, p->fts_namelen + 1);
return (sp->fts_cur = p);
}
/* Move up to the parent node. */
p = tmp->fts_parent;
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);
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 (!ISSET(FTS_NOCHDIR) && 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);
errno = saved_errno;
SET(FTS_STOP);
return (NULL);
}
(void)close(p->fts_symfd);
} else if (!(p->fts_flags & FTS_DONTCHDIR)) {
if (CHDIR(sp, "..")) {
SET(FTS_STOP);
return (NULL);
}
}
p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
return (sp->fts_cur = 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(sp, p, instr)
FTS *sp;
FTSENT *p;
int instr;
{
if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
instr != FTS_NOINSTR && instr != FTS_SKIP) {
errno = EINVAL;
return (1);
}
p->fts_instr = instr;
return (0);
}
FTSENT *
fts_children(sp, instr)
register FTS *sp;
int instr;
{
register FTSENT *p;
int fd;
if (instr && instr != FTS_NAMEONLY) {
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.
*/
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)
fts_lfree(sp->fts_child);
if (instr == FTS_NAMEONLY) {
sp->fts_options |= 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);
}
/*
* 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 FTSENT *
fts_build(sp, type)
register FTS *sp;
int type;
{
register struct dirent *dp;
register FTSENT *p, *head;
register int nitems;
FTSENT *cur, *tail;
DIR *dirp;
void *adjaddr;
int cderrno, descend, len, level, maxlen, nlinks, saved_errno;
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 ((dirp = opendir(cur->fts_accpath)) == 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;
else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL))
nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);
else
nlinks = -1;
#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 (FCHDIR(sp, dirfd(dirp))) {
if (nlinks && type == BREAD)
cur->fts_errno = errno;
cur->fts_flags |= FTS_DONTCHDIR;
descend = 0;
cderrno = errno;
} 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.
*/
maxlen = sp->fts_pathlen - cur->fts_pathlen - 1;
len = NAPPEND(cur);
if (ISSET(FTS_NOCHDIR)) {
cp = sp->fts_path + len;
*cp++ = '/';
}
level = cur->fts_level + 1;
/* Read the directory, attaching each entry to the `link' pointer. */
adjaddr = NULL;
for (head = tail = NULL, nitems = 0; dp = readdir(dirp);) {
if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
continue;
if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL)
goto mem1;
if (dp->d_namlen > maxlen) {
if (fts_palloc(sp, (size_t)dp->d_namlen)) {
/*
* No more memory for path or structures. Save
* errno, free up the current structure and the
* structures already allocated.
*/
mem1: saved_errno = errno;
if (p)
free(p);
fts_lfree(head);
(void)closedir(dirp);
errno = saved_errno;
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
return (NULL);
}
adjaddr = sp->fts_path;
maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1;
}
p->fts_pathlen = len + dp->d_namlen + 1;
p->fts_parent = sp->fts_cur;
p->fts_level = level;
if (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
#ifdef DT_DIR
|| nlinks > 0 &&
dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN
#endif
) {
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;
bcopy(p->fts_name, cp, 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;
}
(void)closedir(dirp);
/*
* If had to realloc the path, adjust the addresses for the rest
* of the tree.
*/
if (adjaddr)
fts_padjust(sp, adjaddr);
/*
* If not changing directories, reset the path back to original
* state.
*/
if (ISSET(FTS_NOCHDIR)) {
if (cp - 1 > sp->fts_path)
--cp;
*cp = '\0';
}
/*
* If descended after called from fts_children or called from
* fts_read and didn't find anything, get back. If can't get
* back, done.
*/
if (descend && (!nitems || type == BCHILD) && CHDIR(sp, "..")) {
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
return (NULL);
}
/* If didn't find anything, return NULL. */
if (!nitems) {
if (type == BREAD)
cur->fts_info = FTS_DP;
return (NULL);
}
/* Sort the entries. */
if (sp->fts_compar && nitems > 1)
head = fts_sort(sp, head, nitems);
return (head);
}
static u_short
fts_stat(sp, p, follow)
FTS *sp;
register FTSENT *p;
int follow;
{
register FTSENT *t;
register dev_t dev;
register 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 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)) {
errno = 0;
return (FTS_SLNONE);
}
p->fts_errno = saved_errno;
goto err;
}
} else if (lstat(p->fts_accpath, sbp)) {
p->fts_errno = errno;
err: bzero(sbp, 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 FTSENT *
fts_sort(sp, head, nitems)
FTS *sp;
FTSENT *head;
register int nitems;
{
register FTSENT **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) {
sp->fts_nitems = nitems + 40;
if ((sp->fts_array = realloc(sp->fts_array,
(size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) {
sp->fts_nitems = 0;
return (head);
}
}
for (ap = sp->fts_array, p = head; p; p = p->fts_link)
*ap++ = p;
qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 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 FTSENT *
fts_alloc(sp, name, namelen)
FTS *sp;
char *name;
register int namelen;
{
register FTSENT *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(FTSENT) + namelen;
if (!ISSET(FTS_NOSTAT))
len += sizeof(struct stat) + ALIGNBYTES;
if ((p = malloc(len)) == NULL)
return (NULL);
/* Copy the name plus the trailing NULL. */
bcopy(name, p->fts_name, namelen + 1);
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
fts_lfree(head)
register FTSENT *head;
{
register FTSENT *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
fts_palloc(sp, more)
FTS *sp;
size_t more;
{
sp->fts_pathlen += more + 256;
sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen);
return (sp->fts_path == NULL);
}
/*
* When the path is realloc'd, have to fix all of the pointers in structures
* already returned.
*/
static void
fts_padjust(sp, addr)
FTS *sp;
void *addr;
{
FTSENT *p;
#define ADJUST(p) { \
(p)->fts_accpath = \
(char *)addr + ((p)->fts_accpath - (p)->fts_path); \
(p)->fts_path = addr; \
}
/* Adjust the current set of children. */
for (p = sp->fts_child; p; p = p->fts_link)
ADJUST(p);
/* Adjust the rest of the tree. */
for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
ADJUST(p);
p = p->fts_link ? p->fts_link : p->fts_parent;
}
}
static size_t
fts_maxarglen(argv)
char * const *argv;
{
size_t len, max;
for (max = 0; *argv; ++argv)
if ((len = strlen(*argv)) > max)
max = len;
return (max);
}