1/* Copyright (c) 1985 Ceriel J.H. Jacobs */
  2
  3#include "in_all.h"
  4#include "help.h"
  5#include "machine.h"
  6#include "commands.h"
  7#include "keys.h"
  8#include "output.h"
  9#include "prompt.h"
 10#include "main.h"
 11#include "display.h"
 12#include "term.h"
 13#include "options.h"
 14
 15static int h_cnt;            /* Count # of lines */
 16static struct state *origin; /* Keep track of startstate */
 17
 18/*
 19 * Print a key sequence.
 20 * We arrived at an endstate. The s_next link in the state structure now
 21 * leads us from "origin" to the current state, so that we can print the key
 22 * sequence easily.
 23 */
 24
 25static void
 26pr_comm()
 27{
 28	struct state *p = origin;
 29	char *pb;
 30	int c;
 31	char buf[30];
 32	int i = 0; /* How many characters printed? */
 33
 34	pb = buf;
 35	for (;;) {
 36		c = p->s_char & 0177;
 37		if (c < ' ' || c == 0177) {
 38			/*
 39			 * Will take an extra position
 40			 */
 41			i++;
 42		}
 43		*pb++ = c;
 44		i++;
 45		if (!p->s_match)
 46			break;
 47		p = p->s_next;
 48	}
 49	do {
 50		*pb++ = ' ';
 51	} while (++i < 12);
 52	*pb = 0;
 53	cputline(buf);
 54}
 55
 56/*
 57 * Print out a description of the keymap. This is done, by temporarily using
 58 * the s_next field in the state structure indicate the state matching the
 59 * next character, so that we can walk from "origin" to an endstate.
 60 */
 61
 62static void
 63pr_mach(struct state *currstate, struct state *back)
 64{
 65	struct state *save;
 66
 67	while (currstate) {
 68		if (interrupt)
 69			break;
 70		if (back) {
 71			save = back->s_next; /* Save original link */
 72			back->s_next = currstate;
 73		}
 74		if (!currstate->s_match) {
 75			/*
 76			 * End state, print command
 77			 */
 78			pr_comm();
 79			putline(commands[currstate->s_cnt].c_descr);
 80			putline("\r\n");
 81			if (++h_cnt >= maxpagesize) {
 82				ret_to_continue();
 83				h_cnt = 0;
 84			}
 85		} else
 86			pr_mach(currstate->s_match, currstate);
 87		currstate = currstate->s_next;
 88		if (back)
 89			back->s_next = save; /* restore */
 90		else
 91			origin = currstate;
 92	}
 93}
 94
 95/*ARGSUSED*/
 96int
 97do_help(long i)
 98{ /* The help command */
 99	(void)i;
100
101	startcomm = 0;
102	h_cnt = 2;
103	putline("\r\nSummary of yap commands:\r\n");
104	origin = currmap->k_mach;
105	pr_mach(currmap->k_mach, (struct state *)0);
106	if (h_cnt) {
107		ret_to_continue();
108	}
109	if (!hardcopy && scr_info.currentpos)
110		redraw(1);
111	return 0;
112}