libutil: Add a stacked, recursive directory tree iterator

The concept is simple: Use the existing, platform dependent iterator
to walk a directory. If a directory entry is encountered, recurse into
it using the open_subdir handler, reconstruct the full path for any
entries discovered using the directory stack.

An additional function is added to skip a sub-hierarchy.

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

5 files changed, 219 insertions, 14 deletions

diff --git a/lib/util/test/dir_iterator.c b/lib/util/test/dir_iterator.c
index d209afd..5ebdaf7 100644
--- a/lib/util/test/dir_iterator.c
+++ b/lib/util/test/dir_iterator.c
@@ -144,25 +144,31 @@ int main(int argc, char **argv)
 	TEST_EQUAL_I(ret, 0);
 
 	ret = dir->next(dir, &ent[5]);
-	TEST_NULL(ent[5]);
+	TEST_NOT_NULL(ent[5]);
+	TEST_EQUAL_I(ret, 0);
+
+	ret = dir->next(dir, &dent);
+	TEST_NULL(dent);
 	TEST_ASSERT(ret > 0);
 
 	dir = sqfs_drop(dir);
 
-	qsort(ent, 5, sizeof(ent[0]), compare_entries);
+	qsort(ent, 6, sizeof(ent[0]), compare_entries);
 
 	TEST_STR_EQUAL(ent[0]->name, ".");
 	TEST_ASSERT(S_ISDIR(ent[0]->mode));
 	TEST_STR_EQUAL(ent[1]->name, "..");
 	TEST_ASSERT(S_ISDIR(ent[1]->mode));
-	TEST_STR_EQUAL(ent[2]->name, "file_b0");
-	TEST_ASSERT(S_ISREG(ent[2]->mode));
-	TEST_STR_EQUAL(ent[3]->name, "file_b1");
+	TEST_STR_EQUAL(ent[2]->name, "dirx");
+	TEST_ASSERT(S_ISDIR(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "file_b0");
 	TEST_ASSERT(S_ISREG(ent[3]->mode));
-	TEST_STR_EQUAL(ent[4]->name, "file_b2");
+	TEST_STR_EQUAL(ent[4]->name, "file_b1");
 	TEST_ASSERT(S_ISREG(ent[4]->mode));
+	TEST_STR_EQUAL(ent[5]->name, "file_b2");
+	TEST_ASSERT(S_ISREG(ent[5]->mode));
 
-	for (i = 0; i < 5; ++i)
+	for (i = 0; i < 6; ++i)
 		free(ent[i]);
 
 	/* scan first sub hierarchy */
@@ -288,7 +294,7 @@ int main(int argc, char **argv)
 		free(ent[i]);
 
 	/* sub iterator b */
-	for (i = 0; i < 5; ++i) {
+	for (i = 0; i < 6; ++i) {
 		ret = subb->next(subb, &ent[i]);
 		TEST_NOT_NULL(ent[0]);
 		TEST_EQUAL_I(ret, 0);
@@ -305,20 +311,22 @@ int main(int argc, char **argv)
 	TEST_ASSERT(ret > 0);
 	subb = sqfs_drop(subb);
 
-	qsort(ent, 5, sizeof(ent[0]), compare_entries);
+	qsort(ent, 6, sizeof(ent[0]), compare_entries);
 
 	TEST_STR_EQUAL(ent[0]->name, ".");
 	TEST_ASSERT(S_ISDIR(ent[0]->mode));
 	TEST_STR_EQUAL(ent[1]->name, "..");
 	TEST_ASSERT(S_ISDIR(ent[1]->mode));
-	TEST_STR_EQUAL(ent[2]->name, "file_b0");
-	TEST_ASSERT(S_ISREG(ent[2]->mode));
-	TEST_STR_EQUAL(ent[3]->name, "file_b1");
+	TEST_STR_EQUAL(ent[2]->name, "dirx");
+	TEST_ASSERT(S_ISDIR(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "file_b0");
 	TEST_ASSERT(S_ISREG(ent[3]->mode));
-	TEST_STR_EQUAL(ent[4]->name, "file_b2");
+	TEST_STR_EQUAL(ent[4]->name, "file_b1");
 	TEST_ASSERT(S_ISREG(ent[4]->mode));
+	TEST_STR_EQUAL(ent[5]->name, "file_b2");
+	TEST_ASSERT(S_ISREG(ent[5]->mode));
 
-	for (i = 0; i < 5; ++i)
+	for (i = 0; i < 6; ++i)
 		free(ent[i]);
 
 	/* sub iterator c */
diff --git a/lib/util/test/dir_tree_iterator.c b/lib/util/test/dir_tree_iterator.c
new file mode 100644
index 0000000..e47efed
--- /dev/null
+++ b/lib/util/test/dir_tree_iterator.c
@@ -0,0 +1,197 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * dir_tree_iterator.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "util/dir_tree_iterator.h"
+#include "sqfs/error.h"
+#include "util/test.h"
+#include "compat.h"
+
+static int compare_entries(const void *a, const void *b)
+{
+	const dir_entry_t *const *lhs = a;
+	const dir_entry_t *const *rhs = b;
+
+	return strcmp((*lhs)->name, (*rhs)->name);
+}
+
+int main(int argc, char **argv)
+{
+	dir_entry_t *ent[17];
+	dir_iterator_t *dir;
+	size_t i;
+	int ret;
+	(void)argc; (void)argv;
+
+	dir = dir_tree_iterator_create(TEST_PATH);
+	TEST_NOT_NULL(dir);
+
+	for (i = 0; i < 16; ++i) {
+		ret = dir->next(dir, &ent[i]);
+		TEST_NOT_NULL(ent[i]);
+		TEST_EQUAL_I(ret, 0);
+		printf("READ %s\n", ent[i]->name);
+	}
+
+	ret = dir->next(dir, &ent[16]);
+	TEST_NULL(ent[16]);
+	TEST_ASSERT(ret > 0);
+
+	dir = sqfs_drop(dir);
+
+	qsort(ent, 16, sizeof(ent[0]), compare_entries);
+
+	printf("After sort:\n");
+	for (i = 0; i < 16; ++i)
+		printf("%s\n", ent[i]->name);
+
+	TEST_STR_EQUAL(ent[0]->name, "dira");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "dira/file_a0");
+	TEST_ASSERT(S_ISREG(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "dira/file_a1");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "dira/file_a2");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "dirb");
+	TEST_ASSERT(S_ISDIR(ent[4]->mode));
+	TEST_STR_EQUAL(ent[5]->name, "dirb/dirx");
+	TEST_ASSERT(S_ISDIR(ent[5]->mode));
+	TEST_STR_EQUAL(ent[6]->name, "dirb/dirx/file_x0");
+	TEST_ASSERT(S_ISREG(ent[6]->mode));
+	TEST_STR_EQUAL(ent[7]->name, "dirb/dirx/file_x1");
+	TEST_ASSERT(S_ISREG(ent[7]->mode));
+	TEST_STR_EQUAL(ent[8]->name, "dirb/dirx/file_x2");
+	TEST_ASSERT(S_ISREG(ent[8]->mode));
+	TEST_STR_EQUAL(ent[9]->name, "dirb/file_b0");
+	TEST_ASSERT(S_ISREG(ent[9]->mode));
+	TEST_STR_EQUAL(ent[10]->name, "dirb/file_b1");
+	TEST_ASSERT(S_ISREG(ent[10]->mode));
+	TEST_STR_EQUAL(ent[11]->name, "dirb/file_b2");
+	TEST_ASSERT(S_ISREG(ent[11]->mode));
+	TEST_STR_EQUAL(ent[12]->name, "dirc");
+	TEST_ASSERT(S_ISDIR(ent[12]->mode));
+	TEST_STR_EQUAL(ent[13]->name, "dirc/file_c0");
+	TEST_ASSERT(S_ISREG(ent[13]->mode));
+	TEST_STR_EQUAL(ent[14]->name, "dirc/file_c1");
+	TEST_ASSERT(S_ISREG(ent[14]->mode));
+	TEST_STR_EQUAL(ent[15]->name, "dirc/file_c2");
+	TEST_ASSERT(S_ISREG(ent[15]->mode));
+
+	for (i = 0; i < 16; ++i)
+		free(ent[i]);
+
+	/* retry with skipping */
+	printf("**********\n");
+
+	dir = dir_tree_iterator_create(TEST_PATH);
+	TEST_NOT_NULL(dir);
+
+	for (i = 0; i < 13; ++i) {
+		ret = dir->next(dir, &ent[i]);
+		TEST_NOT_NULL(ent[i]);
+		TEST_EQUAL_I(ret, 0);
+		printf("READ %s\n", ent[i]->name);
+
+		if (!strcmp(ent[i]->name, "dirb/dirx"))
+			dir_tree_iterator_skip(dir);
+	}
+
+	ret = dir->next(dir, &ent[13]);
+	TEST_NULL(ent[13]);
+	TEST_ASSERT(ret > 0);
+
+	dir = sqfs_drop(dir);
+
+	qsort(ent, 13, sizeof(ent[0]), compare_entries);
+
+	printf("After sort:\n");
+	for (i = 0; i < 13; ++i)
+		printf("%s\n", ent[i]->name);
+
+	TEST_STR_EQUAL(ent[0]->name, "dira");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "dira/file_a0");
+	TEST_ASSERT(S_ISREG(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "dira/file_a1");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "dira/file_a2");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "dirb");
+	TEST_ASSERT(S_ISDIR(ent[4]->mode));
+	TEST_STR_EQUAL(ent[5]->name, "dirb/dirx");
+	TEST_ASSERT(S_ISDIR(ent[5]->mode));
+	TEST_STR_EQUAL(ent[6]->name, "dirb/file_b0");
+	TEST_ASSERT(S_ISREG(ent[6]->mode));
+	TEST_STR_EQUAL(ent[7]->name, "dirb/file_b1");
+	TEST_ASSERT(S_ISREG(ent[7]->mode));
+	TEST_STR_EQUAL(ent[8]->name, "dirb/file_b2");
+	TEST_ASSERT(S_ISREG(ent[8]->mode));
+	TEST_STR_EQUAL(ent[9]->name, "dirc");
+	TEST_ASSERT(S_ISDIR(ent[9]->mode));
+	TEST_STR_EQUAL(ent[10]->name, "dirc/file_c0");
+	TEST_ASSERT(S_ISREG(ent[10]->mode));
+	TEST_STR_EQUAL(ent[11]->name, "dirc/file_c1");
+	TEST_ASSERT(S_ISREG(ent[11]->mode));
+	TEST_STR_EQUAL(ent[12]->name, "dirc/file_c2");
+	TEST_ASSERT(S_ISREG(ent[12]->mode));
+
+	for (i = 0; i < 13; ++i)
+		free(ent[i]);
+
+	/* retry with skipping */
+	printf("**********\n");
+
+	dir = dir_tree_iterator_create(TEST_PATH);
+	TEST_NOT_NULL(dir);
+
+	for (i = 0; i < 9; ++i) {
+		ret = dir->next(dir, &ent[i]);
+		TEST_NOT_NULL(ent[i]);
+		TEST_EQUAL_I(ret, 0);
+		printf("READ %s\n", ent[i]->name);
+
+		if (!strcmp(ent[i]->name, "dirb"))
+			dir_tree_iterator_skip(dir);
+	}
+
+	ret = dir->next(dir, &ent[9]);
+	TEST_NULL(ent[9]);
+	TEST_ASSERT(ret > 0);
+
+	dir = sqfs_drop(dir);
+
+	qsort(ent, 9, sizeof(ent[0]), compare_entries);
+
+	printf("After sort:\n");
+	for (i = 0; i < 9; ++i)
+		printf("%s\n", ent[i]->name);
+
+	TEST_STR_EQUAL(ent[0]->name, "dira");
+	TEST_ASSERT(S_ISDIR(ent[0]->mode));
+	TEST_STR_EQUAL(ent[1]->name, "dira/file_a0");
+	TEST_ASSERT(S_ISREG(ent[1]->mode));
+	TEST_STR_EQUAL(ent[2]->name, "dira/file_a1");
+	TEST_ASSERT(S_ISREG(ent[2]->mode));
+	TEST_STR_EQUAL(ent[3]->name, "dira/file_a2");
+	TEST_ASSERT(S_ISREG(ent[3]->mode));
+	TEST_STR_EQUAL(ent[4]->name, "dirb");
+	TEST_ASSERT(S_ISDIR(ent[4]->mode));
+	TEST_STR_EQUAL(ent[5]->name, "dirc");
+	TEST_ASSERT(S_ISDIR(ent[5]->mode));
+	TEST_STR_EQUAL(ent[6]->name, "dirc/file_c0");
+	TEST_ASSERT(S_ISREG(ent[6]->mode));
+	TEST_STR_EQUAL(ent[7]->name, "dirc/file_c1");
+	TEST_ASSERT(S_ISREG(ent[7]->mode));
+	TEST_STR_EQUAL(ent[8]->name, "dirc/file_c2");
+	TEST_ASSERT(S_ISREG(ent[8]->mode));
+
+	for (i = 0; i < 9; ++i)
+		free(ent[i]);
+
+	return EXIT_SUCCESS;
+}
diff --git a/lib/util/test/testdir/dirb/dirx/file_x0 b/lib/util/test/testdir/dirb/dirx/file_x0
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/lib/util/test/testdir/dirb/dirx/file_x0
diff --git a/lib/util/test/testdir/dirb/dirx/file_x1 b/lib/util/test/testdir/dirb/dirx/file_x1
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/lib/util/test/testdir/dirb/dirx/file_x1
diff --git a/lib/util/test/testdir/dirb/dirx/file_x2 b/lib/util/test/testdir/dirb/dirx/file_x2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/lib/util/test/testdir/dirb/dirx/file_x2