/*
 * 	pkgops.h - Package-related function declarations for libglacier
 *
 * 	This file is part of Glacier.
 *
 * 	Glacier is free software: you can redistribute it and/or modify it under the terms of the
 * 	GNU Lesser General Public License as published by the Free Software Foundation, either
 * 	version 3 of the License, or (at your option) any later version.
 *
 * 	Glacier 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 Lesser General Public License for more details.
 *
 * 	You should have received a copy of the GNU Lesser General Public License along with Glacier. If
 * 	not, see <https://www.gnu.org/licenses/>.
 */

#ifndef GLACIERPKGOPS_H_
#define GLACIERPKGOPS_H_

/* Permission constant for workspace directory creation */
#define DEFAULT_PERMISSIONS 0750

/* Maximum size for path buffers */
#define PATH_MAX_SIZE 512

/*
 * gl_mkworkspace
 *
 * DESCRIPTION: gl_mkworkspace prepares /tmp/glacier-workspace for an operation
 *
 * EXAMPLE:
 * 		gl_mkworkspace();
 *
 * RETURNS: 0 on success, 1 if workspace already exists, -1 on failure
 */
int gl_mkworkspace(void);

/*
 * gl_prepare_pkg
 *
 * DESCRIPTION: gl_prepare_pkg copies a package archive from the localdb, and untars it
 *
 * EXAMPLE:
 * 		gl_prepare_pkg("/glacier/localdb/epkgs-x86_64-musl/foo.tar");
 *
 * RETURNS: 0 on success, 1 on failure
 */
int gl_prepare_pkg(char PACKAGE[]);

/*
 * gl_run_make_task
 *
 * DESCRIPTION: gl_run_make_task runs a specified make task in a package's current working directory
 *
 * EXAMPLE:
 * 		MUST be run after gl_prepare_pkg(), or else errors will occur
 * 		gl_prepare_pkg("/glacier/localdb/epkgs-x86_64-musl/foo.tar");
 * 		gl_run_make_task("installpkg");
 *
 * RETURNS: 0 on success, 1 on failure
 */
int gl_run_make_task(char TASK[]);

/*
 * gl_lock_file
 *
 * DESCRIPTION: Locks a specified file using fcntl
 * PARAMETERS:
 * 		const char *filepath -> The path to the file to lock
 * RETURN VALUES:
 * 		File descriptor on success, -1 on failure
 * CAVEATS:
 * 		The returned file descriptor must be passed to gl_unlock_file() to release the lock
 * EXAMPLE:
 * 		int fd = gl_lock_file("/path/to/file");
 * 		if (fd >= 0) {
 * 			// Do work with locked file
 * 			gl_unlock_file(fd);
 * 		}
 */

int gl_lock_file(const char *filepath);

/*
 * gl_unlock_file
 *
 * DESCRIPTION: Unlocks a specified file using fcntl
 * PARAMETERS:
 * 		int file_descriptor -> The file descriptor returned by gl_lock_file()
 * RETURN VALUES:
 * 		0 on success, 1 on failure
 * CAVEATS:
 * 		Only the process that acquired the lock can release it
 * EXAMPLE:
 * 		gl_unlock_file(file_descriptor);
 */

int gl_unlock_file(int file_descriptor);

#endif