Add code for accessing tar archives

Add implementation of data source for accessing tar files.
This is needed to flash tar.gz file using lthor.

Change-Id: Id5abbf258d41f37c569c65753bb8866bb9a84b6a
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>

2 files changed, 204 insertions, 0 deletions

diff --git a/libthor/thor_internal.h b/libthor/thor_internal.h
index 9e74386..05f7671 100644
--- a/libthor/thor_internal.h
+++ b/libthor/thor_internal.h
@@ -46,5 +46,7 @@ struct thor_device_handle {
 
 int t_file_get_data_src(const char *path, struct thor_data_src **data);
 
+int t_tar_get_data_src(const char *path, struct thor_data_src **data);
+
 #endif /* THOR_INTERNAL_H__ */
 
diff --git a/libthor/thor_tar.c b/libthor/thor_tar.c
new file mode 100644
index 0000000..b74e126
--- /dev/null
+++ b/libthor/thor_tar.c
@@ -0,0 +1,202 @@
+/*
+ * libthor - Tizen Thor communication protocol
+ *
+ * Licensed under the Apache License, Version 2.0 (the License);
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <archive.h>
+#include <archive_entry.h>
+#include <errno.h>
+#include <string.h>
+
+#include "thor.h"
+#include "thor_internal.h"
+
+struct tar_data_src {
+	struct thor_data_src src;
+	struct archive *ar;
+	struct archive_entry *ae;
+	size_t total_size;
+};
+
+static size_t tar_get_file_length(struct thor_data_src *src)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+
+	return archive_entry_size(tardata->ae);
+}
+
+static size_t tar_get_size(struct thor_data_src *src)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+
+	return tardata->total_size;
+}
+
+static size_t tar_get_data_block(struct thor_data_src *src,
+				 void *data, size_t len)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+
+	return archive_read_data(tardata->ar, data, len);
+}
+
+static const char *tar_get_file_name(struct thor_data_src *src)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+
+	return archive_entry_pathname(tardata->ae);
+}
+
+static int tar_next_file(struct thor_data_src *src)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+	int ret;
+
+	ret = archive_read_next_header2(tardata->ar, tardata->ae);
+	if (ret == ARCHIVE_OK)
+		return 1;
+
+	if (ret == ARCHIVE_EOF)
+		return 0;
+
+	return -EINVAL;
+}
+
+static void tar_release(struct thor_data_src *src)
+{
+	struct tar_data_src *tardata =
+		container_of(src, struct tar_data_src, src);
+
+	archive_read_close(tardata->ar);
+	archive_read_finish(tardata->ar);
+	archive_entry_free(tardata->ae);
+	free(tardata);
+}
+
+static int tar_prep_read(const char *path, struct archive **archive,
+			 struct archive_entry **aentry)
+{
+	struct archive *ar;
+	struct archive_entry *ae;
+	int ret;
+
+	ar = archive_read_new();
+	if (!ar)
+		return -ENOMEM;
+
+	ae = archive_entry_new();
+	if (!ae)
+		goto read_finish;
+
+	archive_read_support_format_tar(ar);
+	archive_read_support_compression_gzip(ar);
+	archive_read_support_compression_bzip2(ar);
+
+	if (!strcmp(path, "-"))
+		ret = archive_read_open_FILE(ar, stdin);
+	else
+		ret = archive_read_open_filename(ar, path, 512);
+
+	if (ret)
+		goto cleanup;
+
+	*archive = ar;
+	*aentry = ae;
+	return 0;
+cleanup:
+	archive_entry_free(ae);
+read_finish:
+	archive_read_finish(ar);
+	return ret;
+}
+
+static int tar_calculate_total(const char *path, struct tar_data_src *tardata)
+{
+	struct archive *ar;
+	struct archive_entry *ae;
+	int ret;
+
+	/*
+	 * Yes this is very ugly but libarchive doesn't
+	 * allow to reset position :(
+	 */
+	ret = tar_prep_read(path, &ar, &ae);
+	if (ret)
+		goto out;
+
+	tardata->total_size = 0;
+	while (1) {
+		ret = archive_read_next_header2(ar, ae);
+		if (ret == ARCHIVE_EOF) {
+			break;
+		} else if (ret != ARCHIVE_OK) {
+			tardata->total_size = -EINVAL;
+			goto cleanup;
+		}
+
+		tardata->total_size += archive_entry_size(ae);
+	}
+
+	ret = 0;
+cleanup:
+	archive_read_close(ar);
+	archive_read_finish(ar);
+	archive_entry_free(ae);
+out:
+	return ret;
+}
+
+int t_tar_get_data_src(const char *path, struct thor_data_src **data)
+{
+	struct tar_data_src *tdata;
+	int ret;
+
+	tdata = calloc(1, sizeof(*tdata));
+	if (!tdata)
+		return -ENOMEM;
+
+	/* open the tar archive */
+	ret = tar_prep_read(path, &tdata->ar, &tdata->ae);
+	if (ret)
+		goto free_tdata;
+
+	tdata->src.get_file_length = tar_get_file_length;
+	tdata->src.get_size = tar_get_size;
+	tdata->src.get_block = tar_get_data_block;
+	tdata->src.get_name = tar_get_file_name;
+	tdata->src.next_file = tar_next_file;
+	tdata->src.release = tar_release;
+
+	ret = tar_calculate_total(path, tdata);
+	if (ret < 0)
+		goto read_close;
+
+	*data = &tdata->src;
+	return 0;
+
+read_close:
+	archive_read_close(tdata->ar);
+	archive_entry_free(tdata->ae);
+free_tdata:
+	free(tdata);
+	return ret;
+}
+