libtar: add a dir_iterator_t implementation for tar files

The existing istream_t wrapper is mered into this one as well, we
can open the files via the iterators open_file_ro function. Unit
tests and tar2sqfs are modified accordingly.

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

7 files changed, 337 insertions, 243 deletions

diff --git a/lib/tar/test/data/CREDITS b/lib/tar/test/data/CREDITS
index 1e7fb32..4c20256 100644
--- a/lib/tar/test/data/CREDITS
+++ b/lib/tar/test/data/CREDITS
@@ -33,9 +33,9 @@ The following addtional files have been added:
      Contributed in GitHub issue #64. A tar ball that contains a hard link
      where the 100 byte target field is completely filled without containing
      a null-terminator.
- - istream/sparse.tar
+ - iterator/sparse.tar
      Derived from sparse/gnu.tar and contains some test data for testing the
-     tar istream implementation.
+     tar iterator implementation.
  - write/simple.tar
      Created using the tar writer to verify that it works as intended. Used
      for testing the tar writer to check if it still produces identical
diff --git a/lib/tar/test/data/istream/sparse.tar b/lib/tar/test/data/iterator/sparse.tar
index 7f4700d..7f4700d 100644
--- a/lib/tar/test/data/istream/sparse.tar
+++ b/lib/tar/test/data/iterator/sparse.tar
diff --git a/lib/tar/test/tar_istream.c b/lib/tar/test/tar_istream.c
deleted file mode 100644
index cc31282..0000000
--- a/lib/tar/test/tar_istream.c
+++ /dev/null
@@ -1,73 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-/*
- * tar_istream.c
- *
- * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
- */
-#include "config.h"
-#include "io/file.h"
-#include "tar/tar.h"
-#include "util/test.h"
-
-#ifndef TESTUID
-#define TESTUID 1000
-#endif
-
-#ifndef TESTGID
-#define TESTGID TESTUID
-#endif
-
-#ifndef TESTFNAME
-#define TESTFNAME input.txt
-#endif
-
-#ifndef TESTTS
-#define TESTTS 1542905892
-#endif
-
-static const char *fname = STRVALUE(TESTFNAME);
-
-int main(int argc, char **argv)
-{
-	tar_header_decoded_t hdr;
-	char buffer[100];
-	sqfs_s64 ts;
-	istream_t *fp;
-	istream_t *ti;
-	sqfs_s32 ret;
-	(void)argc; (void)argv;
-
-	fp = istream_open_file(STRVALUE(TESTPATH) "/" STRVALUE(TESTFILE));
-	TEST_NOT_NULL(fp);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFREG | 0644);
-	TEST_EQUAL_UI(hdr.uid, TESTUID);
-	TEST_EQUAL_UI(hdr.gid, TESTGID);
-	TEST_EQUAL_UI(hdr.actual_size, 5);
-
-	ts = TESTTS;
-	TEST_EQUAL_UI(hdr.mtime, ts);
-	TEST_STR_EQUAL(hdr.name, fname);
-	TEST_ASSERT(!hdr.unknown_record);
-
-	ti = tar_record_istream_create(fp, &hdr);
-	TEST_NOT_NULL(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
-	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
-
-	ret = istream_read(ti, buffer, sizeof(buffer));
-	TEST_EQUAL_I(ret, 5);
-	buffer[5] = '\0';
-	TEST_STR_EQUAL(buffer, "test\n");
-
-	ret = istream_read(ti, buffer, sizeof(buffer));
-	TEST_EQUAL_I(ret, 0);
-
-	clear_header(&hdr);
-	sqfs_drop(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	sqfs_drop(fp);
-	return EXIT_SUCCESS;
-}
diff --git a/lib/tar/test/tar_istream2.c b/lib/tar/test/tar_istream2.c
deleted file mode 100644
index e5cdca8..0000000
--- a/lib/tar/test/tar_istream2.c
+++ /dev/null
@@ -1,151 +0,0 @@
-/* SPDX-License-Identifier: GPL-3.0-or-later */
-/*
- * tar_istream2.c
- *
- * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
- */
-#include "config.h"
-#include "io/file.h"
-#include "tar/tar.h"
-#include "util/test.h"
-
-int main(int argc, char **argv)
-{
-	tar_header_decoded_t hdr;
-	char buffer[100];
-	istream_t *fp;
-	istream_t *ti;
-	(void)argc; (void)argv;
-
-	TEST_ASSERT(chdir(TEST_PATH) == 0);
-
-	fp = istream_open_file("format-acceptance/link_filled.tar");
-	TEST_NOT_NULL(fp);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-
-	/* "deep" directory hierarchy containg 2 files */
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/20_characters_here02/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/20_characters_here02/"
-		       "20_characters_here03/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/20_characters_here02/"
-		       "20_characters_here03/20_characters_here04/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFREG | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/20_characters_here02/"
-		       "20_characters_here03/20_characters_here04/"
-		       "errored_file_tst");
-	TEST_EQUAL_UI(hdr.actual_size, 5);
-
-	ti = tar_record_istream_create(fp, &hdr);
-	TEST_NOT_NULL(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
-	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
-	clear_header(&hdr);
-
-	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 5);
-	buffer[5] = '\0';
-	TEST_STR_EQUAL(buffer, "test\n");
-	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 0);
-
-	ti = sqfs_drop(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFREG | 0777);
-	TEST_STR_EQUAL(hdr.name, "20_characters_here01/20_characters_here02/"
-		       "20_characters_here03/20_characters_here04/"
-		       "some_test_file");
-	TEST_EQUAL_UI(hdr.actual_size, 5);
-
-	ti = tar_record_istream_create(fp, &hdr);
-	TEST_NOT_NULL(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
-	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
-	clear_header(&hdr);
-
-	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 5);
-	buffer[5] = '\0';
-	TEST_STR_EQUAL(buffer, "test\n");
-	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 0);
-
-	ti = sqfs_drop(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-
-	/* "deep" directory hierarchy containg a hard link */
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20CharsForLnkTest001/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20CharsForLnkTest001/20CharsForLnkTest002/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20CharsForLnkTest001/20CharsForLnkTest002/"
-		       "20CharsForLnkTest003/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_EQUAL_UI(hdr.mode, S_IFDIR | 0777);
-	TEST_STR_EQUAL(hdr.name, "20CharsForLnkTest001/20CharsForLnkTest002/"
-		       "20CharsForLnkTest003/20CharsForLnkTest004/");
-	clear_header(&hdr);
-
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	TEST_STR_EQUAL(hdr.name, "20CharsForLnkTest001/20CharsForLnkTest002/"
-		       "20CharsForLnkTest003/20CharsForLnkTest004/"
-		       "01234567890123456789");
-	TEST_ASSERT(hdr.is_hard_link);
-
-	TEST_STR_EQUAL(hdr.link_target, "20_characters_here01/"
-		       "20_characters_here02/20_characters_here03/"
-		       "20_characters_here04/errored_file_tst");
-	clear_header(&hdr);
-
-	/* end of file */
-	TEST_ASSERT(read_header(fp, &hdr) > 0);
-	sqfs_drop(fp);
-	return EXIT_SUCCESS;
-}
diff --git a/lib/tar/test/tar_iterator.c b/lib/tar/test/tar_iterator.c
new file mode 100644
index 0000000..21bd3e6
--- /dev/null
+++ b/lib/tar/test/tar_iterator.c
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * tar_iterator.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "io/file.h"
+#include "tar/tar.h"
+#include "util/test.h"
+#include "sqfs/error.h"
+
+#ifndef TESTUID
+#define TESTUID 1000
+#endif
+
+#ifndef TESTGID
+#define TESTGID TESTUID
+#endif
+
+#ifndef TESTFNAME
+#define TESTFNAME input.txt
+#endif
+
+#ifndef TESTTS
+#define TESTTS 1542905892
+#endif
+
+static const char *fname = STRVALUE(TESTFNAME);
+
+int main(int argc, char **argv)
+{
+	istream_t *fp, *ti, *ti2;
+	dir_iterator_t *it;
+	dir_entry_t *ent;
+	char buffer[100];
+	sqfs_s32 ret;
+	sqfs_s64 ts;
+	(void)argc; (void)argv;
+
+	/* Open the file, create an iterator */
+	fp = istream_open_file(STRVALUE(TESTPATH) "/" STRVALUE(TESTFILE));
+	TEST_NOT_NULL(fp);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
+	it = tar_open_stream(fp);
+	TEST_NOT_NULL(it);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 1);
+
+	/* read entry */
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 1);
+
+	ts = TESTTS;
+	TEST_EQUAL_UI(ent->mode, S_IFREG | 0644);
+	TEST_EQUAL_UI(ent->uid, TESTUID);
+	TEST_EQUAL_UI(ent->gid, TESTGID);
+	TEST_EQUAL_UI(ent->mtime, ts);
+	TEST_STR_EQUAL(ent->name, fname);
+	free(ent);
+	ent = NULL;
+
+	/* Open file stream */
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ti);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
+
+	/* test that the iterator is now "locked" */
+	ret = it->open_file_ro(it, &ti2);
+	TEST_EQUAL_I(ret, SQFS_ERROR_SEQUENCE);
+	TEST_NULL(ti2);
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, SQFS_ERROR_SEQUENCE);
+	TEST_NULL(ent);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
+
+	/* read the data from the stream */
+	ret = istream_read(ti, buffer, sizeof(buffer));
+	TEST_EQUAL_I(ret, 5);
+	buffer[5] = '\0';
+	TEST_STR_EQUAL(buffer, "test\n");
+
+	ret = istream_read(ti, buffer, sizeof(buffer));
+	TEST_EQUAL_I(ret, 0);
+
+	sqfs_drop(ti);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 1);
+
+	/* read past EOF on the iterator */
+	ret = it->next(it, &ent);
+	TEST_ASSERT(ret > 0);
+	TEST_NULL(ent);
+
+	/* cleanup */
+	sqfs_drop(it);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
+	sqfs_drop(fp);
+
+	/* re-open the tar iterator */
+	fp = istream_open_file(STRVALUE(TESTPATH) "/" STRVALUE(TESTFILE));
+	TEST_NOT_NULL(fp);
+	it = tar_open_stream(fp);
+	TEST_NOT_NULL(it);
+
+	/* read entry */
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+
+	ts = TESTTS;
+	TEST_EQUAL_UI(ent->mode, S_IFREG | 0644);
+	TEST_EQUAL_UI(ent->uid, TESTUID);
+	TEST_EQUAL_UI(ent->gid, TESTGID);
+	TEST_EQUAL_UI(ent->mtime, ts);
+	TEST_STR_EQUAL(ent->name, fname);
+	free(ent);
+	ent = NULL;
+
+	/* read next entry, mus treturn EOF */
+	ret = it->next(it, &ent);
+	TEST_ASSERT(ret > 0);
+	TEST_NULL(ent);
+
+	/* cleanup */
+	sqfs_drop(it);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
+	sqfs_drop(fp);
+
+	return EXIT_SUCCESS;
+}
diff --git a/lib/tar/test/tar_istream3.c b/lib/tar/test/tar_iterator2.c
index d287081..7f1f3bf 100644
--- a/lib/tar/test/tar_istream3.c
+++ b/lib/tar/test/tar_iterator2.c
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-3.0-or-later */
 /*
- * tar_istream3.c
+ * tar_iterator2.c
  *
  * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
  */
@@ -44,27 +44,34 @@ static int byte_from_offset(uint64_t offset)
 int main(int argc, char **argv)
 {
 	unsigned char buffer[941];
-	tar_header_decoded_t hdr;
+	dir_iterator_t *it;
 	istream_t *fp, *ti;
+	dir_entry_t *ent;
 	uint64_t offset;
 	sqfs_s32 i, ret;
 	(void)argc; (void)argv;
 
 	fp = istream_open_file(STRVALUE(TESTPATH) "/" STRVALUE(TESTFILE));
 	TEST_NOT_NULL(fp);
-	TEST_ASSERT(read_header(fp, &hdr) == 0);
-	TEST_EQUAL_UI(hdr.mode, S_IFREG | 0644);
-	TEST_EQUAL_UI(hdr.uid, 01750);
-	TEST_EQUAL_UI(hdr.gid, 01750);
-	TEST_EQUAL_UI(hdr.actual_size, 2097152);
-	TEST_EQUAL_UI(hdr.record_size, 32768);
-	TEST_STR_EQUAL(hdr.name, "input.bin");
-	TEST_ASSERT(!hdr.unknown_record);
-
-	ti = tar_record_istream_create(fp, &hdr);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
-	TEST_EQUAL_UI(((sqfs_object_t *)ti)->refcount, 1);
-	clear_header(&hdr);
+	it = tar_open_stream(fp);
+	TEST_NOT_NULL(it);
+	sqfs_drop(fp);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+
+	TEST_EQUAL_UI(ent->mode, S_IFREG | 0644);
+	TEST_EQUAL_UI(ent->uid, 01750);
+	TEST_EQUAL_UI(ent->gid, 01750);
+	TEST_EQUAL_UI(ent->size, 2097152);
+	//TEST_EQUAL_UI(ent->on_disk_size, 32768);
+	TEST_STR_EQUAL(ent->name, "input.bin");
+	free(ent);
+
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ti);
 
 	offset = 0;
 
@@ -93,8 +100,7 @@ int main(int argc, char **argv)
 
 	TEST_EQUAL_UI(offset, 2097152);
 
+	sqfs_drop(it);
 	sqfs_drop(ti);
-	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
-	sqfs_drop(fp);
 	return EXIT_SUCCESS;
 }
diff --git a/lib/tar/test/tar_iterator3.c b/lib/tar/test/tar_iterator3.c
new file mode 100644
index 0000000..b2ad6f9
--- /dev/null
+++ b/lib/tar/test/tar_iterator3.c
@@ -0,0 +1,173 @@
+
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * tar_iterator3.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "io/file.h"
+#include "tar/tar.h"
+#include "util/test.h"
+#include "sqfs/error.h"
+
+int main(int argc, char **argv)
+{
+	dir_iterator_t *it;
+	istream_t *fp, *ti;
+	char buffer[100];
+	dir_entry_t *ent;
+	char *link;
+	int ret;
+	(void)argc; (void)argv;
+
+	TEST_ASSERT(chdir(TEST_PATH) == 0);
+
+	fp = istream_open_file("format-acceptance/link_filled.tar");
+	TEST_NOT_NULL(fp);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 1);
+	it = tar_open_stream(fp);
+	TEST_NOT_NULL(it);
+	TEST_EQUAL_UI(((sqfs_object_t *)fp)->refcount, 2);
+	TEST_EQUAL_UI(((sqfs_object_t *)it)->refcount, 1);
+	sqfs_drop(fp);
+
+	/* "deep" directory hierarchy containg 2 files */
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01");
+	free(ent);
+
+	ret = it->read_link(it, &link);
+	TEST_EQUAL_I(ret, SQFS_ERROR_NO_ENTRY);
+	TEST_NULL(link);
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, SQFS_ERROR_NOT_FILE);
+	TEST_NULL(ti);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01/20_characters_here02");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01/20_characters_here02/"
+		       "20_characters_here03");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01/20_characters_here02/"
+		       "20_characters_here03/20_characters_here04");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFREG | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01/20_characters_here02/"
+		       "20_characters_here03/20_characters_here04/"
+		       "errored_file_tst");
+	free(ent);
+
+	ret = it->read_link(it, &link);
+	TEST_EQUAL_I(ret, SQFS_ERROR_NO_ENTRY);
+	TEST_NULL(link);
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ti);
+
+	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 5);
+	buffer[5] = '\0';
+	TEST_STR_EQUAL(buffer, "test\n");
+	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 0);
+	ti = sqfs_drop(ti);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFREG | 0777);
+	TEST_STR_EQUAL(ent->name, "20_characters_here01/20_characters_here02/"
+		       "20_characters_here03/20_characters_here04/"
+		       "some_test_file");
+	free(ent);
+
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ti);
+
+	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 5);
+	buffer[5] = '\0';
+	TEST_STR_EQUAL(buffer, "test\n");
+	TEST_ASSERT(istream_read(ti, buffer, sizeof(buffer)) == 0);
+	ti = sqfs_drop(ti);
+
+	/* "deep" directory hierarchy containg a hard link */
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20CharsForLnkTest001");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20CharsForLnkTest001/20CharsForLnkTest002");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20CharsForLnkTest001/20CharsForLnkTest002/"
+		       "20CharsForLnkTest003");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_EQUAL_UI(ent->mode, S_IFDIR | 0777);
+	TEST_STR_EQUAL(ent->name, "20CharsForLnkTest001/20CharsForLnkTest002/"
+		       "20CharsForLnkTest003/20CharsForLnkTest004");
+	free(ent);
+
+	ret = it->next(it, &ent);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(ent);
+	TEST_STR_EQUAL(ent->name, "20CharsForLnkTest001/20CharsForLnkTest002/"
+		       "20CharsForLnkTest003/20CharsForLnkTest004/"
+		       "01234567890123456789");
+	TEST_EQUAL_UI(ent->mode, S_IFLNK | 0777);
+	TEST_ASSERT((ent->flags & DIR_ENTRY_FLAG_HARD_LINK) != 0);
+	free(ent);
+
+	ret = it->read_link(it, &link);
+	TEST_EQUAL_I(ret, 0);
+	TEST_NOT_NULL(link);
+	ret = it->open_file_ro(it, &ti);
+	TEST_EQUAL_I(ret, SQFS_ERROR_NOT_FILE);
+	TEST_NULL(ti);
+
+	TEST_STR_EQUAL(link, "20_characters_here01/"
+		       "20_characters_here02/20_characters_here03/"
+		       "20_characters_here04/errored_file_tst");
+	free(link);
+
+	/* end of file */
+	ret = it->next(it, &ent);
+	TEST_ASSERT(ret > 0);
+	TEST_NULL(ent);
+	sqfs_drop(it);
+	return EXIT_SUCCESS;
+}