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authorCem Keylan <cem@ckyln.com>2020-10-16 17:41:25 +0300
committerCem Keylan <cem@ckyln.com>2020-10-16 17:41:25 +0300
commite2abcdca396661cbe0ae2ddb13d5c2b85682c13a (patch)
treeacf9b5c80b645617f882c45224c6e07251711842 /lib/libc/gen/fts.c
downloadotools-e2abcdca396661cbe0ae2ddb13d5c2b85682c13a.tar.gz
initial commit
Diffstat (limited to 'lib/libc/gen/fts.c')
-rw-r--r--lib/libc/gen/fts.c1053
1 files changed, 1053 insertions, 0 deletions
diff --git a/lib/libc/gen/fts.c b/lib/libc/gen/fts.c
new file mode 100644
index 0000000..982dd87
--- /dev/null
+++ b/lib/libc/gen/fts.c
@@ -0,0 +1,1053 @@
+/* $OpenBSD: fts.c,v 1.59 2019/06/28 13:32:41 deraadt Exp $ */
+
+/*-
+ * 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.
+ * 3. 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.
+ */
+
+#include <sys/param.h> /* ALIGN */
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <fts.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#define MAXIMUM(a, b) (((a) > (b)) ? (a) : (b))
+
+static FTSENT *fts_alloc(FTS *, char *, size_t);
+static FTSENT *fts_build(FTS *, int);
+static void fts_lfree(FTSENT *);
+static void fts_load(FTS *, FTSENT *);
+static size_t fts_maxarglen(char * const *);
+static void fts_padjust(FTS *, FTSENT *);
+static int fts_palloc(FTS *, size_t);
+static FTSENT *fts_sort(FTS *, FTSENT *, int);
+static u_short fts_stat(FTS *, FTSENT *, int, int);
+static int fts_safe_changedir(FTS *, FTSENT *, int, char *);
+
+#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 */
+
+FTS *
+fts_open(char * const *argv, int options,
+ int (*compar)(const FTSENT **, const FTSENT **))
+{
+ FTS *sp;
+ FTSENT *p, *root;
+ int nitems;
+ FTSENT *parent, *prev;
+
+ /* Options check. */
+ if (options & ~FTS_OPTIONMASK) {
+ errno = EINVAL;
+ return (NULL);
+ }
+
+ /* At least one path must be specified. */
+ if (*argv == NULL) {
+ errno = EINVAL;
+ return (NULL);
+ }
+
+ /* Allocate/initialize the stream */
+ if ((sp = calloc(1, sizeof(FTS))) == NULL)
+ return (NULL);
+ 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.
+ */
+ if (fts_palloc(sp, MAXIMUM(fts_maxarglen(argv), PATH_MAX)))
+ 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 = prev = NULL, nitems = 0; *argv; ++argv, ++nitems) {
+ if ((p = fts_alloc(sp, *argv, strlen(*argv))) == NULL)
+ goto mem3;
+ 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), -1);
+
+ /* 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)
+ root = p;
+ else
+ prev->fts_link = p;
+ prev = 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 | O_CLOEXEC)) == -1)
+ SET(FTS_NOCHDIR);
+
+ if (nitems == 0)
+ free(parent);
+
+ return (sp);
+
+mem3: fts_lfree(root);
+ free(parent);
+mem2: free(sp->fts_path);
+mem1: free(sp);
+ return (NULL);
+}
+DEF_WEAK(fts_open);
+
+static void
+fts_load(FTS *sp, FTSENT *p)
+{
+ size_t 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(FTS *sp)
+{
+ FTSENT *freep, *p;
+ int rfd, error = 0;
+
+ /*
+ * 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);
+ }
+
+ /* Stash the original directory fd if needed. */
+ rfd = ISSET(FTS_NOCHDIR) ? -1 : sp->fts_rfd;
+
+ /* Free up child linked list, sort array, path buffer, stream ptr.*/
+ if (sp->fts_child)
+ fts_lfree(sp->fts_child);
+ free(sp->fts_array);
+ free(sp->fts_path);
+ free(sp);
+
+ /* Return to original directory, checking for error. */
+ if (rfd != -1) {
+ int saved_errno;
+ error = fchdir(rfd);
+ saved_errno = errno;
+ (void)close(rfd);
+ errno = saved_errno;
+ }
+
+ return (error);
+}
+DEF_WEAK(fts_close);
+
+/*
+ * 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)
+
+FTSENT *
+fts_read(FTS *sp)
+{
+ FTSENT *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, -1);
+ 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, -1);
+ if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
+ if ((p->fts_symfd =
+ open(".", O_RDONLY | O_CLOEXEC)) == -1) {
+ 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 && 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) {
+ 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; 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 (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 (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, -1);
+ if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
+ if ((p->fts_symfd =
+ open(".", O_RDONLY | O_CLOEXEC)) == -1) {
+ 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 (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 (FCHDIR(sp, sp->fts_rfd)) {
+ SET(FTS_STOP);
+ sp->fts_cur = p;
+ 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);
+ sp->fts_cur = p;
+ 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);
+ sp->fts_cur = p;
+ return (NULL);
+ }
+ p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
+ return (sp->fts_cur = p);
+}
+DEF_WEAK(fts_read);
+
+/*
+ * 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.
+ */
+int
+fts_set(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);
+}
+DEF_WEAK(fts_set);
+
+FTSENT *
+fts_children(FTS *sp, int instr)
+{
+ 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) {
+ 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 | O_CLOEXEC)) == -1)
+ return (NULL);
+ sp->fts_child = fts_build(sp, instr);
+ if (fchdir(fd)) {
+ (void)close(fd);
+ return (NULL);
+ }
+ (void)close(fd);
+ return (sp->fts_child);
+}
+DEF_WEAK(fts_children);
+
+/*
+ * 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(FTS *sp, int type)
+{
+ struct dirent *dp;
+ FTSENT *p, *head;
+ FTSENT *cur, *tail;
+ DIR *dirp;
+ void *oldaddr;
+ size_t len, maxlen;
+ int nitems, cderrno, descend, level, nlinks, nostat, doadjust;
+ int saved_errno;
+ char *cp;
+ size_t namlen;
+
+ /* 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);
+ nostat = 1;
+ } else {
+ nlinks = -1;
+ nostat = 0;
+ }
+
+#ifdef notdef
+ (void)printf("nlinks == %d (cur: %u)\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++ = '/';
+ }
+ len++;
+ maxlen = sp->fts_pathlen - len;
+
+ /*
+ * fts_level is signed so we must prevent it from wrapping
+ * around to FTS_ROOTLEVEL and FTS_ROOTPARENTLEVEL.
+ */
+ level = cur->fts_level;
+ if (level < FTS_MAXLEVEL)
+ level++;
+
+ /* 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;
+
+ namlen = strlen(dp->d_name);
+ if (!(p = fts_alloc(sp, dp->d_name, namlen)))
+ goto mem1;
+ if (namlen >= maxlen) { /* include space for NUL */
+ oldaddr = sp->fts_path;
+ if (fts_palloc(sp, namlen +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);
+ 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;
+ }
+
+ p->fts_level = level;
+ p->fts_parent = sp->fts_cur;
+ p->fts_pathlen = len + namlen;
+ if (p->fts_pathlen < len) {
+ /*
+ * If we wrap, 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);
+ errno = ENAMETOOLONG;
+ return (NULL);
+ }
+
+ 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
+ || (nostat &&
+ 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;
+ memmove(cp, p->fts_name, p->fts_namelen + 1);
+ p->fts_info = fts_stat(sp, p, 0, dirfd(dirp));
+ } else {
+ p->fts_accpath = p->fts_name;
+ p->fts_info = fts_stat(sp, p, 0, -1);
+ }
+
+ /* 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);
+ 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(FTS *sp, FTSENT *p, int follow, int dfd)
+{
+ FTSENT *t;
+ dev_t dev;
+ ino_t ino;
+ struct stat *sbp, sb;
+ int saved_errno;
+ const char *path;
+
+ if (dfd == -1) {
+ path = p->fts_accpath;
+ dfd = AT_FDCWD;
+ } else
+ path = p->fts_name;
+
+ /* 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 (fstatat(dfd, path, sbp, 0)) {
+ saved_errno = errno;
+ if (!fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW)) {
+ errno = 0;
+ return (FTS_SLNONE);
+ }
+ p->fts_errno = saved_errno;
+ goto err;
+ }
+ } else if (fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW)) {
+ 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 FTSENT *
+fts_sort(FTS *sp, FTSENT *head, int nitems)
+{
+ 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) {
+ struct _ftsent **a;
+
+ if ((a = reallocarray(sp->fts_array,
+ nitems + 40, sizeof(FTSENT *))) == NULL) {
+ free(sp->fts_array);
+ sp->fts_array = NULL;
+ sp->fts_nitems = 0;
+ return (head);
+ }
+ sp->fts_nitems = nitems + 40;
+ sp->fts_array = a;
+ }
+ for (ap = sp->fts_array, p = head; p; p = p->fts_link)
+ *ap++ = p;
+ qsort(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(FTS *sp, char *name, size_t namelen)
+{
+ 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 = calloc(1, len)) == NULL)
+ return (NULL);
+
+ p->fts_path = sp->fts_path;
+ p->fts_namelen = namelen;
+ p->fts_instr = FTS_NOINSTR;
+ if (!ISSET(FTS_NOSTAT))
+ p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2);
+ memcpy(p->fts_name, name, namelen);
+
+ return (p);
+}
+
+static void
+fts_lfree(FTSENT *head)
+{
+ 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 PATH_MAX, 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(FTS *sp, size_t more)
+{
+ char *p;
+
+ /*
+ * Check for possible wraparound.
+ */
+ more += 256;
+ if (sp->fts_pathlen + more < sp->fts_pathlen) {
+ free(sp->fts_path);
+ sp->fts_path = NULL;
+ errno = ENAMETOOLONG;
+ return (1);
+ }
+ p = recallocarray(sp->fts_path, sp->fts_pathlen,
+ sp->fts_pathlen + more, 1);
+ if (p == NULL) {
+ free(sp->fts_path);
+ sp->fts_path = NULL;
+ return (1);
+ }
+ sp->fts_pathlen += more;
+ 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
+fts_padjust(FTS *sp, FTSENT *head)
+{
+ FTSENT *p;
+ char *addr = sp->fts_path;
+
+#define ADJUST(p) { \
+ if ((p)->fts_accpath != (p)->fts_name) { \
+ (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, 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
+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
+fts_safe_changedir(FTS *sp, FTSENT *p, int fd, char *path)
+{
+ int ret, oerrno, newfd;
+ struct stat sb;
+
+ newfd = fd;
+ if (ISSET(FTS_NOCHDIR))
+ return (0);
+ if (fd == -1 && (newfd = open(path, O_RDONLY|O_DIRECTORY|O_CLOEXEC)) == -1)
+ return (-1);
+ if (fstat(newfd, &sb) == -1) {
+ ret = -1;
+ goto bail;
+ }
+ if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {
+ errno = ENOENT; /* disinformation */
+ ret = -1;
+ goto bail;
+ }
+ ret = fchdir(newfd);
+bail:
+ oerrno = errno;
+ if (fd == -1)
+ (void)close(newfd);
+ errno = oerrno;
+ return (ret);
+}