libropkg: add functions for extracting metadata from package files

libropkg/package.c

@@ -0,0 +1,132 @@
+#include "reader.h"
+
+#include <blue/core/error.h>
+#include <blue/io/directory.h>
+#include <ropkg/reader.h>
+
+static b_result extract_file(
+	struct ropkg_reader *pkg,
+	const char *path_cstr,
+	b_directory *dest)
+{
+	b_path *path = b_path_create_from_cstr(path_cstr);
+	if (!path) {
+		return ROPKG_RESULT_ERR(NO_MEMORY);
+	}
+
+	b_path *dir_path = NULL;
+	b_path_get_directory(path, &dir_path);
+	if (!dir_path) {
+		b_path_release(path);
+		return ROPKG_RESULT_ERR(NO_MEMORY);
+	}
+
+	b_result result = B_RESULT_SUCCESS;
+	if (b_path_length(dir_path) > 0) {
+		b_directory *parent_dir;
+		result = b_directory_open(
+			dest,
+			dir_path,
+			B_DIRECTORY_OPEN_CREATE_INTERMEDIATE,
+			&parent_dir);
+		b_directory_release(parent_dir);
+	}
+
+	if (b_result_is_error(result)) {
+		goto end;
+	}
+
+	b_file *dest_file = NULL;
+	result = b_file_open(
+		dest,
+		path,
+		B_FILE_WRITE_ONLY | B_FILE_CREATE | B_FILE_BINARY,
+		&dest_file);
+	if (b_result_is_error(result)) {
+		goto end;
+	}
+
+	char data[] = "Hello";
+	size_t nr_written = 0;
+	b_file_write(dest_file, 0, sizeof data, data, &nr_written);
+	b_file_release(dest_file);
+
+end:
+	b_path_release(path);
+	b_path_release(dir_path);
+	return result;
+}
+
+static b_result extract_subpackage(
+	struct ropkg_reader *pkg,
+	const char *name,
+	b_directory *dest)
+{
+	b_directory *dest_subdir;
+	b_result result = b_directory_open(
+		dest,
+		B_RV_PATH(name),
+		B_DIRECTORY_OPEN_CREATE,
+		&dest_subdir);
+	if (b_result_is_error(result)) {
+		return result;
+	}
+
+	b_cstream_begin_compressed_section(pkg->r_stream, NULL);
+
+	struct ropkg_reader *subpkg = NULL;
+	enum ropkg_status status = ropkg_reader_open(pkg->r_stream, &subpkg);
+	if (status != ROPKG_SUCCESS) {
+		result = ROPKG_RESULT_STATUS(status);
+		goto end;
+	}
+
+	while (!ropkg_reader_eof(subpkg)) {
+		const struct ropkg_file_info *file
+			= ropkg_reader_current_file(subpkg);
+		result = extract_file(subpkg, file->f_filename, dest_subdir);
+		if (b_result_is_error(result)) {
+			break;
+		}
+
+		status = ropkg_reader_move_next(subpkg);
+		if (status != ROPKG_SUCCESS) {
+			result = ROPKG_RESULT_STATUS(status);
+			break;
+		}
+	}
+
+end:
+	b_cstream_end_compressed_section(pkg->r_stream, NULL, NULL);
+	return result;
+}
+
+b_result ropkg_extract_metadata(struct ropkg_reader *pkg, b_directory *dest)
+{
+	b_result result = B_RESULT_SUCCESS;
+
+	while (!ropkg_reader_eof(pkg)) {
+		const struct ropkg_file_info *file
+			= ropkg_reader_current_file(pkg);
+
+		int section = -1;
+
+		if (!strncmp(file->f_filename, "meta.tar", 8)) {
+			result = extract_subpackage(pkg, "meta", dest);
+		} else if (!strncmp(file->f_filename, "control.tar", 11)) {
+			result = extract_subpackage(pkg, "control", dest);
+		}
+
+		if (b_result_is_error(result)) {
+			break;
+		}
+
+		enum ropkg_status status = ropkg_reader_move_next(pkg);
+		if (status != ROPKG_SUCCESS) {
+			result = ROPKG_RESULT_STATUS(status);
+			break;
+		}
+	}
+
+	return result;
+}