1 files changed, 126 insertions, 0 deletions
diff --git a/lib/dpkg/fsys-iter.c b/lib/dpkg/fsys-iter.c
new file mode 100644
index 0000000..807aabb
--- /dev/null
+++ b/lib/dpkg/fsys-iter.c
@@ -0,0 +1,126 @@
+/*
+ * libdpkg - Debian packaging suite library routines
+ * fsys-iter.c - filesystem nodes iterators
+ *
+ * Copyright © 1995 Ian Jackson <ijackson@chiark.greenend.org.uk>
+ * Copyright © 2000, 2001 Wichert Akkerman <wakkerma@debian.org>
+ * Copyright © 2008-2014 Guillem Jover <guillem@debian.org>
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <compat.h>
+
+#include <stdlib.h>
+
+#include <dpkg/dpkg.h>
+#include <dpkg/dpkg-db.h>
+#include <dpkg/pkg-list.h>
+
+#include "fsys.h"
+
+/*
+ * Reverse iterator.
+ */
+
+/*
+ * Initializes an iterator that appears to go through the file list ‘files’
+ * in reverse order, returning the namenode from each. What actually happens
+ * is that we walk the list here, building up a reverse list, and then peel
+ * it apart one entry at a time.
+ */
+void
+fsys_hash_rev_iter_init(struct fsys_hash_rev_iter *iter,
+                        struct fsys_namenode_list *files)
+{
+	struct fsys_namenode_list *newent;
+
+	iter->todo = NULL;
+	while (files) {
+		newent = m_malloc(sizeof(*newent));
+		newent->namenode = files->namenode;
+		newent->next = iter->todo;
+		iter->todo = newent;
+		files = files->next;
+	}
+}
+
+struct fsys_namenode *
+fsys_hash_rev_iter_next(struct fsys_hash_rev_iter *iter)
+{
+	struct fsys_namenode *next;
+	struct fsys_namenode_list *todo;
+
+	todo = iter->todo;
+	if (!todo)
+		return NULL;
+	next = todo->namenode;
+	iter->todo = todo->next;
+	free(todo);
+
+	return next;
+}
+
+/*
+ * Clients must call this function to clean up the fsys_hash_rev_iter
+ * if they wish to break out of the iteration before it is all done.
+ * Calling this function is not necessary if fsys_hash_rev_iter_next() has
+ * been called until it returned 0.
+ */
+void
+fsys_hash_rev_iter_abort(struct fsys_hash_rev_iter *iter)
+{
+	while (fsys_hash_rev_iter_next(iter))
+		;
+}
+
+/*
+ * Iterator for packages owning a file.
+ */
+
+struct fsys_node_pkgs_iter {
+	struct pkg_list *pkg_node;
+};
+
+struct fsys_node_pkgs_iter *
+fsys_node_pkgs_iter_new(struct fsys_namenode *fnn)
+{
+	struct fsys_node_pkgs_iter *iter;
+
+	iter = m_malloc(sizeof(*iter));
+	iter->pkg_node = fnn->packages;
+
+	return iter;
+}
+
+struct pkginfo *
+fsys_node_pkgs_iter_next(struct fsys_node_pkgs_iter *iter)
+{
+	struct pkg_list *pkg_node;
+
+	if (iter->pkg_node == NULL)
+		return NULL;
+
+	pkg_node = iter->pkg_node;
+	iter->pkg_node = pkg_node->next;
+
+	return pkg_node->pkg;
+}
+
+void
+fsys_node_pkgs_iter_free(struct fsys_node_pkgs_iter *iter)
+{
+	free(iter);
+}