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authorSalvatore Cro <salvatore.cro at st.com>2011-04-20 12:49:25 +0200
committerBernhard Reutner-Fischer <rep.dot.nop@gmail.com>2011-04-20 12:50:38 +0200
commita4aa01c128b04c7174d57a28f61656f966d2bd6c (patch)
tree2783135b8c0322cbce4d502c7394bedcecfcbbbf /libc/misc/fts/fts.c
parent3a411b5d8a6c6311778e22280706047cd1a8c8d4 (diff)
Added fts support for traversing UNIX file hierarchies.
It is required by libdwfl in elfutils package. Signed-off-by: Salvatore Cro <salvatore.cro at st.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Diffstat (limited to 'libc/misc/fts/fts.c')
-rw-r--r--libc/misc/fts/fts.c1145
1 files changed, 1145 insertions, 0 deletions
diff --git a/libc/misc/fts/fts.c b/libc/misc/fts/fts.c
new file mode 100644
index 000000000..ce5d1586b
--- /dev/null
+++ b/libc/misc/fts/fts.c
@@ -0,0 +1,1145 @@
+/*-
+ * 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.
+ */
+
+#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>
+
+#ifdef __UCLIBC_HAS_LFS__
+# include <_lfs_64.h>
+#else
+# define stat64 stat
+# define fstat64 fstat
+#endif
+
+/* 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 (FTS *, const char *, size_t) internal_function;
+static FTSENT *fts_build (FTS *, int) internal_function;
+static void fts_lfree (FTSENT *) internal_function;
+static void fts_load (FTS *, FTSENT *) internal_function;
+static size_t fts_maxarglen (char * const *) internal_function;
+static void fts_padjust (FTS *, FTSENT *) internal_function;
+static int fts_palloc (FTS *, size_t) internal_function;
+static FTSENT *fts_sort (FTS *, FTSENT *, int) internal_function;
+static u_short fts_stat (FTS *, FTSENT *, int) internal_function;
+static int fts_safe_changedir (FTS *, FTSENT *, 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 */
+
+FTS *
+fts_open(argv, options, compar)
+ char * const *argv;
+ register int options;
+ int (*compar) (const FTSENT **, const FTSENT **);
+{
+ register FTS *sp;
+ register FTSENT *p, *root;
+ register int nitems;
+ FTSENT *parent = NULL;
+ FTSENT *tmp = NULL;
+
+ /* Options check. */
+ if (options & ~FTS_OPTIONMASK) {
+ __set_errno (EINVAL);
+ return (NULL);
+ }
+
+ /* Allocate/initialize the stream */
+ if ((sp = malloc((u_int)sizeof(FTS))) == NULL)
+ return (NULL);
+ memset(sp, 0, sizeof(FTS));
+ 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(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;
+ 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(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 != 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)
+
+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 != 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(sp, p, instr)
+ FTS *sp;
+ FTSENT *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);
+}
+
+FTSENT *
+fts_children(sp, instr)
+ register FTS *sp;
+ int instr;
+{
+ register FTSENT *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);
+}
+
+/*
+ * 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 *
+internal_function
+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 *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
+
+#if 0
+ /* 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 (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
+#endif
+ if (nlinks == 0
+#if defined DT_DIR && defined _DIRENT_HAVE_D_TYPE
+ || (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);
+ } 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(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 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 FTSENT *
+internal_function
+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) {
+ struct _ftsent **a;
+
+ sp->fts_nitems = nitems + 40;
+ if ((a = realloc(sp->fts_array,
+ (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == 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(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 *
+internal_function
+fts_alloc(sp, name, namelen)
+ FTS *sp;
+ const char *name;
+ size_t 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 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(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
+internal_function
+fts_palloc(sp, more)
+ FTS *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(sp, head)
+ FTS *sp;
+ FTSENT *head;
+{
+ FTSENT *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(argv)
+ 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(sp, p, fd, path)
+ FTS *sp;
+ FTSENT *p;
+ int fd;
+ const char *path;
+{
+ int ret, oerrno, newfd;
+ struct stat64 sb;
+
+ newfd = fd;
+ if (ISSET(FTS_NOCHDIR))
+ return (0);
+ if (fd < 0 && (newfd = open(path, O_RDONLY, 0)) < 0)
+ return (-1);
+ if (fstat64(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);
+}