text: /*
   * Copyright (c) 2005-2006, Kohsuke Ohtani
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the author nor the names of any co-contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  #include <sys/prex.h>
  
  #include <limits.h>
  #include <ctype.h>
  #include <unistd.h>
  #include <string.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <libgen.h>
  #include <termios.h>
  
  #include "cmdbox.h"
  
  #ifdef CONFIG_CMD_SH
  extern int sh_main(int argc, char *argv[]);
  #endif
  
  int
  null_main(int argc, char *argv[])
  {
  	return -1;
  }
  
  int
  help_main(int argc, char *argv[])
  {
  	struct cmdentry const *entry;
  	struct winsize ws;
  	int maxcol, col = 0;
  
  	/* Get screen size */
  	maxcol = 80;
  	if (ioctl(fileno(stderr), TIOCGWINSZ, &ws) == 0)
  		maxcol = (int)ws.ws_col;
  	if (maxcol < 80)
  		maxcol -= 15;
  	else
  		maxcol -= 25;
  
  	fprintf(stderr, "usage: cmdbox [command] [arguments]...\n");
  	fprintf(stderr, "builtin commands:\n");
  
  	/*
  	 * Show help for builtin commands.
  	 */
  	entry = builtin_cmds;
  	while (entry->cmd != NULL) {
  		col += fprintf(stderr, "%s%s", ((col == 0) ? "    " : ", "),
  			       entry->cmd);
  		entry++;
  		if (col > maxcol && entry->cmd != NULL) {
  			fprintf(stderr, ",\n");
  			col = 0;
  		}
  	}
  
  #ifdef CONFIG_CMD_SH
  	/*
  	 * Show help for shell commands.
  	 */
  	entry = shell_cmds;
  	while (entry->cmd != NULL) {
  		col += fprintf(stderr, "%s%s", ((col == 0) ? "    " : ", "),
  			       entry->cmd);
  		entry++;
  		if (col > maxcol && entry->cmd != NULL) {
  			fprintf(stderr, ",\n");
  			col = 0;
  		}
  	}
  #endif
  	fprintf(stderr, "\nuse `-?` to find out more about each command.\n");
  	return 0;
  }
  
  int
  main(int argc, char *argv[])
  {
  	char *prog, *cmd;
  	struct cmdentry const *entry;
  	int shcmd = 0;
  
  	prog = basename(argv[0]);
  	cmd = prog;
  
  	/*
  	 * Alias:
  	 * 'sh'            => sh
  	 * 'cmdbox'        => sh
  	 * 'cmdbox sh'     => sh
  	 * 'cmdbox cmd'    => cmd
  	 * 'cmd' (symlink) => cmd
  	 */
  	if (!strcmp(prog, "sh"))
  		shcmd = 1;
  	else if (!strcmp(prog, "cmdbox")) {
  		if (argc == 1)
  			shcmd = 1;
  		else {
  			if (!strcmp(argv[1], "sh"))
  				shcmd = 1;
  			else
  				cmd = argv[1];
  			argv++;
  			argc--;
  		}
  	}
  
  	if (shcmd) {
  		task_setname(task_self(), "sh");
  		exit(sh_main(argc, argv));
  	}
  
  	entry = builtin_cmds;
  	while (entry->cmd != NULL) {
  		if (!strcmp(cmd, entry->cmd)) {
  			task_setname(task_self(), cmd);
  			exit(entry->func(argc, argv));
  		}
  		entry++;
  	}
  	fprintf(stderr, "No such command: %s\n", cmd);
  	return 0;
  }
  