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>

1 files changed, 106 insertions, 0 deletions

diff --git a/lib/tar/test/tar_iterator2.c b/lib/tar/test/tar_iterator2.c
new file mode 100644
index 0000000..7f1f3bf
--- /dev/null
+++ b/lib/tar/test/tar_iterator2.c
@@ -0,0 +1,106 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * tar_iterator2.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "io/file.h"
+#include "tar/tar.h"
+#include "util/test.h"
+
+static const struct {
+	uint64_t offset;
+	size_t size;
+	int fill;
+} regions[] = {
+	{       0, 4096, 'A' },
+	{  262144, 4096, 'B' },
+	{  524288, 4096, 'C' },
+	{  786432, 4096, 'D' },
+	{ 1048576, 4096, 'E' },
+	{ 1310720, 4096, 'F' },
+	{ 1572864, 4096, 'G' },
+	{ 1835008, 4096, 'H' },
+};
+
+static int byte_from_offset(uint64_t offset)
+{
+	sqfs_u64 diff;
+	size_t i;
+
+	for (i = 0; i < sizeof(regions) / sizeof(regions[0]); ++i) {
+		if (offset >= regions[i].offset) {
+			diff = (offset - regions[i].offset);
+
+			if (diff < regions[i].size)
+				return regions[i].fill;
+		}
+	}
+
+	return '\0';
+}
+
+int main(int argc, char **argv)
+{
+	unsigned char buffer[941];
+	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);
+	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;
+
+	for (;;) {
+		ret = istream_read(ti, buffer, sizeof(buffer));
+		TEST_ASSERT(ret >= 0);
+
+		if (ret == 0)
+			break;
+
+		for (i = 0; i < ret; ++i) {
+			int ref_byte = byte_from_offset(offset + i);
+
+			if (buffer[i] != ref_byte) {
+				fprintf(stderr, "Byte at offset %llu should "
+					"be 0x%02X, but is 0x%02X\n",
+					(unsigned long long)(offset + i),
+					(unsigned int)ref_byte, buffer[i]);
+				return EXIT_FAILURE;
+			}
+		}
+
+		offset += ret;
+		TEST_ASSERT(offset <= 2097152);
+	}
+
+	TEST_EQUAL_UI(offset, 2097152);
+
+	sqfs_drop(it);
+	sqfs_drop(ti);
+	return EXIT_SUCCESS;
+}