Add generic function to produce a full path from an fstree node

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

4 files changed, 50 insertions, 42 deletions

diff --git a/include/fstree.h b/include/fstree.h
index 284792b..ef2ffb1 100644
--- a/include/fstree.h
+++ b/include/fstree.h
@@ -254,4 +254,12 @@ int fstree_relabel_selinux(fstree_t *fs, const char *filename);
 /* Returns 0 on success. Prints to stderr on failure */
 int fstree_gen_inode_table(fstree_t *fs);
 
+/*
+  Generate a string holding the full path of a node. Returned
+  string must be freed.
+
+  Returns NULL on failure and sets errno.
+*/
+char *fstree_get_path(tree_node_t *node);
+
 #endif /* FSTREE_H */
diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index bf4ed61..618fbf2 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -1,6 +1,7 @@
 libfstree_a_SOURCES = lib/fstree/fstree.c lib/fstree/fstree_from_file.c
 libfstree_a_SOURCES += lib/fstree/fstree_sort.c lib/fstree/fstree_from_dir.c
-libfstree_a_SOURCES += lib/fstree/gen_inode_table.c include/fstree.h
+libfstree_a_SOURCES += lib/fstree/gen_inode_table.c lib/fstree/get_path.c
+libfstree_a_SOURCES += include/fstree.h
 libfstree_a_CFLAGS = $(AM_CFLAGS)
 libfstree_a_CPPFLAGS = $(AM_CPPFLAGS)
 
diff --git a/lib/fstree/get_path.c b/lib/fstree/get_path.c
new file mode 100644
index 0000000..4b6f61e
--- /dev/null
+++ b/lib/fstree/get_path.c
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "fstree.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+char *fstree_get_path(tree_node_t *node)
+{
+	tree_node_t *it;
+	char *str, *ptr;
+	size_t len = 0;
+
+	if (node->parent == NULL)
+		return strdup("/");
+
+	for (it = node; it != NULL && it->parent != NULL; it = it->parent) {
+		len += strlen(it->name) + 1;
+	}
+
+	str = malloc(len + 1);
+	if (str == NULL)
+		return NULL;
+
+	ptr = str + len;
+	*ptr = '\0';
+
+	for (it = node; it != NULL && it->parent != NULL; it = it->parent) {
+		len = strlen(it->name);
+		ptr -= len;
+
+		memcpy(ptr, it->name, len);
+		*(--ptr) = '/';
+	}
+
+	return str;
+}
diff --git a/lib/fstree/selinux.c b/lib/fstree/selinux.c
index ef858f2..ec14a93 100644
--- a/lib/fstree/selinux.c
+++ b/lib/fstree/selinux.c
@@ -10,45 +10,6 @@
 #define XATTR_NAME_SELINUX "security.selinux"
 #define XATTR_VALUE_SELINUX "system_u:object_r:unlabeled_t:s0"
 
-static char *get_path(tree_node_t *node)
-{
-	tree_node_t *it;
-	char *str, *ptr;
-	size_t len = 0;
-
-	if (node->parent == NULL) {
-		str = strdup("/");
-
-		if (str == NULL)
-			goto fail_alloc;
-		return str;
-	}
-
-	for (it = node; it != NULL && it->parent != NULL; it = it->parent) {
-		len += strlen(it->name) + 1;
-	}
-
-	str = malloc(len + 1);
-	if (str == NULL)
-		goto fail_alloc;
-
-	ptr = str + len;
-	*ptr = '\0';
-
-	for (it = node; it != NULL && it->parent != NULL; it = it->parent) {
-		len = strlen(it->name);
-		ptr -= len;
-
-		memcpy(ptr, it->name, len);
-		*(--ptr) = '/';
-	}
-
-	return str;
-fail_alloc:
-	perror("relabeling files");
-	return NULL;
-}
-
 static int relable_node(fstree_t *fs, struct selabel_handle *sehnd,
 			tree_node_t *node)
 {
@@ -56,9 +17,11 @@ static int relable_node(fstree_t *fs, struct selabel_handle *sehnd,
 	tree_node_t *it;
 	int ret;
 
-	path = get_path(node);
-	if (path == NULL)
+	path = fstree_get_path(node);
+	if (path == NULL) {
+		perror("relabeling files");
 		return -1;
+	}
 
 	if (selabel_lookup(sehnd, &context, path, node->mode) < 0) {
 		free(path);