init/servicecmd/servicecmd.c

/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * Copyright (C) 2018 - David Oberhollenzer
 *
 * This program 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.
 *
 * This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
 */
#include <stdlib.h>
#include <stdio.h>

#include "servicecmd.h"
#include "service.h"
#include "config.h"
#include "util.h"


command_t *commands;

extern char *__progname;


void usage(int status)
{
	FILE *stream = (status == EXIT_SUCCESS ? stdout : stderr);
	int padd = 0, len;
	command_t *cmd;

	fprintf(stream, "usage: %s <command> [args...]\n\n"
			"Available commands:\n\n", __progname);

	for (cmd = commands; cmd != NULL; cmd = cmd->next) {
		len = strlen(cmd->cmd);

		padd = len > padd ? len : padd;
	}

	for (cmd = commands; cmd != NULL; cmd = cmd->next) {
		fprintf(stream, "%*s - %s\n",
			(int)padd + 1, cmd->cmd, cmd->s_desc);
	}

	fprintf(stream, "\nTry `%s help <command>' for more information "
			"on a specific command\n", __progname);

	exit(status);
}

void tell_read_help(const char *cmd)
{
	fprintf(stderr, "Try `%s help %s' for more information.\n",
		__progname, cmd);
}

int check_arguments(const char *cmd, int argc, int minc, int maxc)
{
	if (argc >= minc && argc <= maxc)
		return 0;

	fprintf(stderr, "Too %s arguments for `%s'\n",
			argc > maxc ? "many" : "few", cmd);
	tell_read_help(cmd);
	return -1;
}

int main(int argc, char **argv)
{
	command_t *cmd;

	if (argc < 2)
		usage(EXIT_SUCCESS);

	for (cmd = commands; cmd != NULL; cmd = cmd->next) {
		if (!strcmp(cmd->cmd, argv[1])) {
			return cmd->run_cmd(argc - 1, argv + 1);
		}
	}

	fprintf(stderr, "Unknown command '%s'\n\n", argv[1]);
	usage(EXIT_FAILURE);
}