libtar: Add a test for the tar writing code

Generate a simple tarball and compare it with a reference.

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

4 files changed, 232 insertions, 1 deletions

diff --git a/lib/tar/Makemodule.am b/lib/tar/Makemodule.am
index 9faeecf..07eb497 100644
--- a/lib/tar/Makemodule.am
+++ b/lib/tar/Makemodule.am
@@ -179,6 +179,11 @@ test_tar_istream3_CPPFLAGS += -DTESTFILE=istream/sparse.tar
 tar_fuzz_SOURCES = lib/tar/test/tar_fuzz.c
 tar_fuzz_LDADD = libtar.a libio.a libutil.a libcompat.a
 
+test_tar_write_simple_SOURCES = lib/tar/test/tar_write_simple.c
+test_tar_write_simple_LDADD = libtar.a libio.a libutil.a libcompat.a
+test_tar_write_simple_CPPFLAGS = $(AM_CPPFLAGS) -DTESTPATH=$(TARDATADIR)
+test_tar_write_simple_CPPFLAGS += -DTESTFILE=write/simple.tar
+
 LIBTAR_TESTS = \
 	test_tar_ustar0 test_tar_ustar1 test_tar_ustar2 test_tar_ustar3 \
 	test_tar_ustar4 test_tar_ustar5 test_tar_ustar6 \
@@ -190,7 +195,8 @@ LIBTAR_TESTS = \
 	test_tar_sparse_gnu2 test_tar_sparse_gnu3 \
 	test_tar_xattr_bsd test_tar_xattr_schily test_tar_xattr_schily_bin \
 	test_tar_target_filled \
-	test_tar_istream test_tar_istream2 test_tar_istream3
+	test_tar_istream test_tar_istream2 test_tar_istream3 \
+	test_tar_write_simple
 
 check_PROGRAMS += $(LIBTAR_TESTS)
 TESTS += $(LIBTAR_TESTS)
diff --git a/lib/tar/test/data/CREDITS b/lib/tar/test/data/CREDITS
index dab8951..1e7fb32 100644
--- a/lib/tar/test/data/CREDITS
+++ b/lib/tar/test/data/CREDITS
@@ -36,3 +36,7 @@ The following addtional files have been added:
  - istream/sparse.tar
      Derived from sparse/gnu.tar and contains some test data for testing the
      tar istream 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
+     output.
diff --git a/lib/tar/test/data/write/simple.tar b/lib/tar/test/data/write/simple.tar
new file mode 100644
index 0000000..a910daa
--- /dev/null
+++ b/lib/tar/test/data/write/simple.tar
diff --git a/lib/tar/test/tar_write_simple.c b/lib/tar/test/tar_write_simple.c
new file mode 100644
index 0000000..c78565b
--- /dev/null
+++ b/lib/tar/test/tar_write_simple.c
@@ -0,0 +1,221 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * tar_write_simple.c
+ *
+ * Copyright (C) 2023 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "tar/tar.h"
+#include "io/ostream.h"
+#include "io/file.h"
+#include "util/test.h"
+#include "compat.h"
+
+/*****************************************************************************/
+
+static int buffer_append(ostream_t *strm, const void *data, size_t size);
+static const char *buffer_get_filename(ostream_t *strm);
+
+static ostream_t mem_stream = {
+	{ 1, NULL, NULL },
+	buffer_append,
+	NULL,
+	NULL,
+	buffer_get_filename,
+};
+
+static sqfs_u8 wr_buffer[1024 * 10];
+static size_t wr_offset = 0;
+
+static sqfs_u8 rd_buffer[1024 * 10];
+
+static int buffer_append(ostream_t *strm, const void *data, size_t size)
+{
+	TEST_ASSERT(strm == &mem_stream);
+	TEST_NOT_NULL(data);
+	TEST_ASSERT(wr_offset < sizeof(wr_buffer));
+	TEST_ASSERT(size > 0);
+	TEST_ASSERT((sizeof(wr_buffer) - wr_offset) >= size);
+
+	memcpy(wr_buffer + wr_offset, data, size);
+	wr_offset += size;
+	return 0;
+}
+
+static const char *buffer_get_filename(ostream_t *strm)
+{
+	TEST_ASSERT(strm == &mem_stream);
+	return "dummy";
+}
+
+/*****************************************************************************/
+
+#define TIME_STAMP (1057296600)
+
+static tar_xattr_t *mkxattr(const char *key, const sqfs_u8 *value,
+			    size_t value_len)
+{
+	size_t key_len = strlen(key);
+	tar_xattr_t *out = malloc(sizeof(*out) + key_len + 1 + value_len + 1);
+
+	TEST_NOT_NULL(out);
+
+	out->next = NULL;
+	out->key = out->data;
+	out->value = (sqfs_u8 *)(out->data + key_len + 1);
+	out->value_len = value_len;
+
+	memcpy(out->data, key, key_len);
+	out->data[key_len] = '\0';
+
+	memcpy(out->data + key_len + 1, value, value_len);
+	out->data[key_len + 1 + value_len] = '\0';
+
+	return out;
+}
+
+static tar_xattr_t *mkxattr_chain(void)
+{
+	static const uint8_t value[] = {
+		0x00, 0x00, 0x00, 0x02,
+		0x00, 0x30, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00,
+	};
+	tar_xattr_t *list;
+
+	list = mkxattr("user.mime_type", (const sqfs_u8 *)"blob/magic", 10);
+	list->next = mkxattr("security.capability", value, sizeof(value));
+
+	return list;
+}
+
+int main(int argc, char **argv)
+{
+	tar_xattr_t *xattr;
+	struct stat sb;
+	istream_t *fp;
+	int ret;
+	(void)argc; (void)argv;
+
+	/* genereate some archive contents */
+	memset(&sb, 0, sizeof(sb));
+	sb.st_mode = S_IFDIR | 0755;
+	sb.st_mtime = TIME_STAMP;
+	ret = write_tar_header(&mem_stream, &sb, "dev/", NULL, NULL, 0);
+	TEST_EQUAL_I(ret, 0);
+
+	/* device files */
+	sb.st_mode = S_IFCHR | 0620;
+	sb.st_gid = 5;
+	sb.st_rdev = makedev(4, 0);
+	ret = write_tar_header(&mem_stream, &sb, "dev/tty0", NULL, NULL, 1);
+	TEST_EQUAL_I(ret, 0);
+
+	sb.st_rdev = makedev(4, 1);
+	ret = write_tar_header(&mem_stream, &sb, "dev/tty1", NULL, NULL, 2);
+	TEST_EQUAL_I(ret, 0);
+
+	sb.st_rdev = makedev(4, 2);
+	ret = write_tar_header(&mem_stream, &sb, "dev/tty2", NULL, NULL, 3);
+	TEST_EQUAL_I(ret, 0);
+
+	memset(&sb, 0, sizeof(sb));
+	sb.st_mode = S_IFDIR | 0755;
+	sb.st_mtime = TIME_STAMP;
+	ret = write_tar_header(&mem_stream, &sb, "usr/", NULL, NULL, 4);
+	TEST_EQUAL_I(ret, 0);
+
+	ret = write_tar_header(&mem_stream, &sb, "usr/bin/", NULL, NULL, 5);
+	TEST_EQUAL_I(ret, 0);
+
+	/* sym link */
+	sb.st_mode = S_IFLNK | 0777;
+	sb.st_size = 7;
+	ret = write_tar_header(&mem_stream, &sb, "bin", "usr/bin", NULL, 6);
+	TEST_EQUAL_I(ret, 0);
+
+	memset(&sb, 0, sizeof(sb));
+	sb.st_mode = S_IFDIR | 0755;
+	sb.st_mtime = TIME_STAMP;
+	ret = write_tar_header(&mem_stream, &sb, "home/", NULL, NULL, 7);
+	TEST_EQUAL_I(ret, 0);
+
+	sb.st_mode = S_IFDIR | 0750;
+	sb.st_uid = 1000;
+	sb.st_gid = 1000;
+	ret = write_tar_header(&mem_stream, &sb, "home/goliath/",
+			       NULL, NULL, 8);
+	TEST_EQUAL_I(ret, 0);
+
+	/* regular file with actual content */
+	sb.st_mode = S_IFREG | 0644;
+	sb.st_size = 14;
+	ret = write_tar_header(&mem_stream, &sb, "home/goliath/hello.txt",
+			       NULL, NULL, 9);
+	TEST_EQUAL_I(ret, 0);
+
+	ret = ostream_append(&mem_stream, "Hello, World!\n", 14);
+	TEST_EQUAL_I(ret, 0);
+	ret = padd_file(&mem_stream, 14);
+	TEST_EQUAL_I(ret, 0);
+
+	/* hard link */
+	ret = write_hard_link(&mem_stream, &sb, "home/goliath/world.txt",
+			      "home/goliath/hello.txt", 10);
+	TEST_EQUAL_I(ret, 0);
+
+	/* something with xattrs */
+	xattr = mkxattr_chain();
+	sb.st_mode = S_IFREG | 0750;
+	sb.st_size = 4;
+	ret = write_tar_header(&mem_stream, &sb, "home/goliath/test.exe",
+			       NULL, xattr, 11);
+	TEST_EQUAL_I(ret, 0);
+	free_xattr_list(xattr);
+
+	ret = ostream_append(&mem_stream, ":-)\n", 4);
+	TEST_EQUAL_I(ret, 0);
+	ret = padd_file(&mem_stream, 4);
+	TEST_EQUAL_I(ret, 0);
+
+	/* now try something with a long name */
+	memset(&sb, 0, sizeof(sb));
+	sb.st_mode = S_IFREG | 0755;
+	sb.st_mtime = TIME_STAMP;
+	sb.st_size = 42;
+	ret = write_tar_header(&mem_stream, &sb,
+			       "mnt/windows_drive/C/Documents and Settings/"
+			       "Joe Random User/My Documents/My Evil Plans/"
+			       "file format nonsense/really long name.doc",
+			       NULL, NULL, 12);
+	TEST_EQUAL_I(ret, 0);
+
+	ret = ostream_append(&mem_stream,
+			     "Annoy people with really long file paths!\n",
+			     42);
+	TEST_EQUAL_I(ret, 0);
+	ret = padd_file(&mem_stream, 42);
+	TEST_EQUAL_I(ret, 0);
+
+	/* compare with reference */
+	TEST_EQUAL_UI(wr_offset, sizeof(wr_buffer));
+	TEST_EQUAL_UI(sizeof(rd_buffer), sizeof(wr_buffer));
+
+	fp = istream_open_file(STRVALUE(TESTPATH) "/" STRVALUE(TESTFILE));
+	TEST_NOT_NULL(fp);
+
+	ret = istream_read(fp, rd_buffer, sizeof(rd_buffer));
+	TEST_ASSERT(ret > 0);
+	TEST_EQUAL_UI(ret, sizeof(rd_buffer));
+
+	ret = istream_read(fp, rd_buffer, sizeof(rd_buffer));
+	TEST_EQUAL_I(ret, 0);
+
+	sqfs_drop(fp);
+
+	ret = memcmp(wr_buffer, rd_buffer, sizeof(rd_buffer));
+	TEST_EQUAL_I(ret, 0);
+	return EXIT_SUCCESS;
+}