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diff --git a/contrib/libarchive/examples/minitar/tree.c b/contrib/libarchive/examples/minitar/tree.c
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+++ b/contrib/libarchive/examples/minitar/tree.c
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+/*-
+ * Copyright (c) 2003-2004 Tim Kientzle
+ * 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
+ *    in this position and unchanged.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 AUTHOR(S) 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.
+ */
+
+/*-
+ * There is a single list of "tree_entry" items that represent
+ * filesystem objects that require further attention.  Non-directories
+ * are not kept in memory: they are pulled from readdir(), returned to
+ * the client, then freed as soon as possible.  Any directory entry to
+ * be traversed gets pushed onto the stack.
+ *
+ * There is surprisingly little information that needs to be kept for
+ * each item on the stack.  Just the name, depth (represented here as the
+ * string length of the parent directory's pathname), and some markers
+ * indicating how to get back to the parent (via chdir("..") for a
+ * regular dir or via fchdir(2) for a symlink).
+ */
+
+#include <sys/stat.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "tree.h"
+
+/*
+ * TODO:
+ *    1) Loop checking.
+ *    3) Arbitrary logical traversals by closing/reopening intermediate fds.
+ */
+
+struct tree_entry {
+	struct tree_entry *next;
+	char *name;
+	size_t dirname_length;
+	int fd;
+	int flags;
+};
+
+/* Definitions for tree_entry.flags bitmap. */
+#define isDir 1 /* This entry is a regular directory. */
+#define isDirLink 2 /* This entry is a symbolic link to a directory. */
+#define needsTraversal 4 /* This entry hasn't yet been traversed. */
+
+/*
+ * Local data for this package.
+ */
+struct tree {
+	struct tree_entry	*stack;
+	DIR	*d;
+	int	 initialDirFd;
+	int	 flags;
+
+	char	*buff;
+	char	*basename;
+	size_t	 buff_length;
+	size_t	 path_length;
+	size_t	 dirname_length;
+
+	int	 depth;
+	int	 openCount;
+	int	 maxOpenCount;
+
+	struct stat	lst;
+	struct stat	st;
+};
+
+/* Definitions for tree.flags bitmap. */
+#define needsReturn 8  /* Marks first entry as not having been returned yet. */
+#define hasStat 16  /* The st entry is set. */
+#define hasLstat 32 /* The lst entry is set. */
+
+
+#define HAVE_DIRENT_D_NAMLEN 1
+#ifdef HAVE_DIRENT_D_NAMLEN
+/* BSD extension; avoids need for a strlen() call. */
+#define D_NAMELEN(dp)	(dp)->d_namlen
+#else
+#define D_NAMELEN(dp)	(strlen((dp)->d_name))
+#endif
+
+#if 0
+static void
+dumpStack(struct tree *t)
+{
+	struct tree_entry *te;
+
+	printf("\tbuff: %s\n", t->buff);
+	printf("\tpwd: "); fflush(stdout); system("pwd");
+	printf("\tstack:\n");
+	for (te = t->stack; te != NULL; te = te->next) {
+		printf("\t\tte->name: %s %s\n", te->name, te->flags & needsTraversal ? "" : "*");
+	}
+}
+#endif
+
+/*
+ * Add a directory path to the current stack.
+ */
+static void
+tree_add(struct tree *t, const char *path)
+{
+	struct tree_entry *te;
+
+	te = malloc(sizeof(*te));
+	memset(te, 0, sizeof(*te));
+	te->next = t->stack;
+	t->stack = te;
+	te->fd = -1;
+	te->name = strdup(path);
+	te->flags = needsTraversal;
+	te->dirname_length = t->dirname_length;
+}
+
+/*
+ * Append a name to the current path.
+ */
+static void
+tree_append(struct tree *t, const char *name, size_t name_length)
+{
+	if (t->buff != NULL)
+		t->buff[t->dirname_length] = '\0';
+
+	/* Resize pathname buffer as needed. */
+	while (name_length + 1 + t->dirname_length >= t->buff_length) {
+		t->buff_length *= 2;
+		if (t->buff_length < 1024)
+			t->buff_length = 1024;
+		t->buff = realloc(t->buff, t->buff_length);
+	}
+	t->basename = t->buff + t->dirname_length;
+	t->path_length = t->dirname_length + name_length;
+	if (t->dirname_length > 0) {
+		*t->basename++ = '/';
+		t->path_length ++;
+	}
+	strcpy(t->basename, name);
+}
+
+/*
+ * Open a directory tree for traversal.
+ */
+struct tree *
+tree_open(const char *path)
+{
+	struct tree *t;
+
+	t = malloc(sizeof(*t));
+	memset(t, 0, sizeof(*t));
+	tree_append(t, path, strlen(path));
+	t->initialDirFd = open(".", O_RDONLY);
+	/*
+	 * During most of the traversal, items are set up and then
+	 * returned immediately from tree_next().  That doesn't work
+	 * for the very first entry, so we set a flag for this special
+	 * case.
+	 */
+	t->flags = needsReturn;
+	return (t);
+}
+
+/*
+ * We've finished a directory; ascend back to the parent.
+ */
+static void
+tree_ascend(struct tree *t)
+{
+	struct tree_entry *te;
+
+	te = t->stack;
+	t->depth--;
+	if (te->flags & isDirLink) {
+		fchdir(te->fd);
+		close(te->fd);
+		t->openCount--;
+	} else {
+		chdir("..");
+	}
+}
+
+/*
+ * Pop the working stack.
+ */
+static void
+tree_pop(struct tree *t)
+{
+	struct tree_entry *te;
+
+	te = t->stack;
+	t->stack = te->next;
+	t->dirname_length = te->dirname_length;
+	free(te->name);
+	free(te);
+}
+
+/*
+ * Get the next item in the tree traversal.
+ */
+int
+tree_next(struct tree *t)
+{
+	struct dirent *de = NULL;
+
+	/* Handle the startup case by returning the initial entry. */
+	if (t->flags & needsReturn) {
+		t->flags &= ~needsReturn;
+		return (1);
+	}
+
+	while (t->stack != NULL) {
+		/* If there's an open dir, get the next entry from there. */
+		while (t->d != NULL) {
+			de = readdir(t->d);
+			if (de == NULL) {
+				closedir(t->d);
+				t->d = NULL;
+			} else if (de->d_name[0] == '.'
+			    && de->d_name[1] == '\0') {
+				/* Skip '.' */
+			} else if (de->d_name[0] == '.'
+			    && de->d_name[1] == '.'
+			    && de->d_name[2] == '\0') {
+				/* Skip '..' */
+			} else {
+				/*
+				 * Append the path to the current path
+				 * and return it.
+				 */
+				tree_append(t, de->d_name, D_NAMELEN(de));
+				t->flags &= ~hasLstat;
+				t->flags &= ~hasStat;
+				return (1);
+			}
+		}
+
+		/* If the current dir needs to be traversed, set it up. */
+		if (t->stack->flags & needsTraversal) {
+			tree_append(t, t->stack->name, strlen(t->stack->name));
+			t->stack->flags &= ~needsTraversal;
+			/* If it is a link, set up fd for the ascent. */
+			if (t->stack->flags & isDirLink) {
+				t->stack->fd = open(".", O_RDONLY);
+				t->openCount++;
+				if (t->openCount > t->maxOpenCount)
+					t->maxOpenCount = t->openCount;
+			}
+			if (chdir(t->stack->name) == 0) {
+				t->depth++;
+				t->dirname_length = t->path_length;
+				t->d = opendir(".");
+			} else
+				tree_pop(t);
+			continue;
+		}
+
+		/* We've done everything necessary for the top stack entry. */
+		tree_ascend(t);
+		tree_pop(t);
+	}
+	return (0);
+}
+
+/*
+ * Called by the client to mark the directory just returned from
+ * tree_next() as needing to be visited.
+ */
+void
+tree_descend(struct tree *t)
+{
+	const struct stat *s = tree_current_lstat(t);
+
+	if (S_ISDIR(s->st_mode)) {
+		tree_add(t, t->basename);
+		t->stack->flags |= isDir;
+	}
+
+	if (S_ISLNK(s->st_mode) && S_ISDIR(tree_current_stat(t)->st_mode)) {
+		tree_add(t, t->basename);
+		t->stack->flags |= isDirLink;
+	}
+}
+
+/*
+ * Get the stat() data for the entry just returned from tree_next().
+ */
+const struct stat *
+tree_current_stat(struct tree *t)
+{
+	if (!(t->flags & hasStat)) {
+		stat(t->basename, &t->st);
+		t->flags |= hasStat;
+	}
+	return (&t->st);
+}
+
+/*
+ * Get the lstat() data for the entry just returned from tree_next().
+ */
+const struct stat *
+tree_current_lstat(struct tree *t)
+{
+	if (!(t->flags & hasLstat)) {
+		lstat(t->basename, &t->lst);
+		t->flags |= hasLstat;
+	}
+	return (&t->lst);
+}
+
+/*
+ * Return the access path for the entry just returned from tree_next().
+ */
+const char *
+tree_current_access_path(struct tree *t)
+{
+	return (t->basename);
+}
+
+/*
+ * Return the full path for the entry just returned from tree_next().
+ */
+const char *
+tree_current_path(struct tree *t)
+{
+	return (t->buff);
+}
+
+/*
+ * Return the length of the path for the entry just returned from tree_next().
+ */
+size_t
+tree_current_pathlen(struct tree *t)
+{
+	return (t->path_length);
+}
+
+/*
+ * Return the nesting depth of the entry just returned from tree_next().
+ */
+int
+tree_current_depth(struct tree *t)
+{
+	return (t->depth);
+}
+
+/*
+ * Terminate the traversal and release any resources.
+ */
+void
+tree_close(struct tree *t)
+{
+	/* Release anything remaining in the stack. */
+	while (t->stack != NULL)
+		tree_pop(t);
+	if (t->buff)
+		free(t->buff);
+	/* chdir() back to where we started. */
+	if (t->initialDirFd >= 0) {
+		fchdir(t->initialDirFd);
+		close(t->initialDirFd);
+		t->initialDirFd = -1;
+	}
+	free(t);
+}
+
+
+#if 0
+/* Main function for testing. */
+#include <stdio.h>
+
+int main(int argc, char **argv)
+{
+	size_t max_path_len = 0;
+	int max_depth = 0;
+
+	system("pwd");
+	while (*++argv) {
+		struct tree *t = tree_open(*argv);
+		while (tree_next(t)) {
+			size_t path_len = tree_current_pathlen(t);
+			int depth = tree_current_depth(t);
+			if (path_len > max_path_len)
+				max_path_len = path_len;
+			if (depth > max_depth)
+				max_depth = depth;
+			printf("%s\n", tree_current_path(t));
+			if (S_ISDIR(tree_current_lstat(t)->st_mode))
+				tree_descend(t); /* Descend into every dir. */
+		}
+		tree_close(t);
+		printf("Max path length: %d\n", max_path_len);
+		printf("Max depth: %d\n", max_depth);
+		printf("Final open count: %d\n", t->openCount);
+		printf("Max open count: %d\n", t->maxOpenCount);
+		fflush(stdout);
+		system("pwd");
+	}
+	return (0);
+}
+#endif