/*
 * Copyright (C) 2023  Patrick McDermott
 *
 * This file is part of opkg-opkg.
 *
 * opkg-opkg is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * opkg-opkg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with opkg-opkg.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef OPKG_OPK_OPK_H_
#define OPKG_OPK_OPK_H_

#include "ustar.h"

struct opkg_opk_opk;

/*
 * Allocates and initializes a package structure.
 * Parameters:
 * - file_name: Package's file name.
 * Returns:
 * - Allocated package structure on success.  Free with
 *   opkg_opk_opk_free_outer().
 * - NULL on memory exhaustion.
 */
struct opkg_opk_opk *
opkg_opk_opk_init_outer(const char *file_name);

/*
 * Initializes an inner archive of a package.  Free with
 * opkg_opk_opk_free_outer().  May be called again after freeing.
 * Parameters:
 * - opk:    Package structure.
 * - member: Name of member file to find and prepare to read.  Should be either
 *   "control.tar.gz" or "data.tar.gz", in that order if both are to be read.
 * Returns:
 * - OPKG_OPK_OK if the inner archive is found and initialized.
 * - OPKG_OPK_ERROR if no matching member is found or on decompression error,
 *   premature end of gzip stream, an invalid header, unsupported file type, or
 *   memory exhaustion.
 */
int
opkg_opk_opk_init_inner(struct opkg_opk_opk *opk, const char *member);

/*
 * Reads and prints all specified control files.
 * Parameters:
 * - opk:   Package structure.
 * - names: List of control file names to read.
 * Returns:
 * - OPKG_OPK_OK if all control files are found, read, and printed.
 * - OPKG_OPK_ERROR if any control file is not found or on decompression error,
 *   premature end of gzip stream, an invalid header, unsupported file type, or
 *   error writing to standard output.
 */
int
opkg_opk_opk_read_control(struct opkg_opk_opk *opk,
		struct opkg_opk_ustar_seek_name *names);

/*
 * Lists and prints all data files.
 * Parameters:
 * - opk: Package structure.
 * Returns:
 * - OPKG_OPK_OK if all data files are listed and printed.
 * - OPKG_OPK_ERROR on decompression error, memory exhaustion, mode or mtime
 *   integer conversion error, unsupported file type, or error writing to
 *   standard output.
 */
int
opkg_opk_opk_list_members(struct opkg_opk_opk *opk);

/*
 * Frees a package structure's inner archive.  Call before
 * opkg_opk_opk_free_outer() if a opkg_opk_opk_init_inner() call succeeds.
 * Parameters:
 * - opk: Package structure.
 */
void
opkg_opk_opk_free_inner(struct opkg_opk_opk *opk);

/*
 * Frees a package structure.  Call opkg_opk_opk_free_inner() first after a
 * successful opkg_opk_opk_init_inner() call.
 * Parameters:
 * - opk: Package structure.
 */
void
opkg_opk_opk_free_outer(struct opkg_opk_opk *opk);

#endif  /* OPKG_OPK_OPK_H_ */