libropkg: implement tar file reader

libropkg/include/ropkg/reader.h

@@ -0,0 +1,33 @@
+#ifndef ROPKG_READER_H_
+#define ROPKG_READER_H_
+
+#include <ropkg/misc.h>
+#include <ropkg/status.h>
+
+struct ropkg_reader;
+struct b_cstream;
+
+struct ropkg_file_info {
+	char f_filename[255];
+	int f_mode;
+	int f_uid, f_gid;
+	unsigned long f_filesize;
+	unsigned long f_mtime;
+	int f_type;
+	char f_linkname[100];
+};
+
+ROPKG_API enum ropkg_status ropkg_reader_open(
+	struct b_cstream *fp,
+	struct ropkg_reader **out);
+ROPKG_API enum ropkg_status ropkg_reader_close(struct ropkg_reader *pkg);
+
+ROPKG_API const struct ropkg_file_info *ropkg_reader_current_file(
+	struct ropkg_reader *reader);
+ROPKG_API enum ropkg_status ropkg_reader_move_next(struct ropkg_reader *pkg);
+ROPKG_API enum ropkg_status ropkg_reader_move_to_file(
+	struct ropkg_reader *pkg,
+	const char *name);
+ROPKG_API bool ropkg_reader_eof(const struct ropkg_reader *pkg);
+
+#endif