[unix-history] / usr / src / usr.bin / more / prompt.c

/*
 * Copyright (c) 1988 Mark Nudleman
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by Mark Nudleman and the University of California, Berkeley.  The
 * name of Mark Nudleman or the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)prompt.c	5.4 (Berkeley) %G%";
#endif /* not lint */

/*
 * Prompting and other messages.
 * There are three flavors of prompts, SHORT, MEDIUM and LONG,
 * selected by the -m/-M options.
 * There is also the "equals message", printed by the = command.
 * A prompt is a message composed of various pieces, such as the 
 * name of the file being viewed, the percentage into the file, etc.
 */

#include "less.h"
#include "position.h"

extern int pr_type;
extern int ispipe;
extern int hit_eof;
extern int new_file;
extern int sc_width;
extern int so_width, se_width;
extern char *current_file;
extern int ac;
extern char **av;
extern int curr_ac;
extern int linenums;

/*
 * Prototypes for the three flavors of prompts.
 * These strings are expanded by pr_expand().
 */
static char s_proto[] =
  "?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x..%t";
static char m_proto[] =
  "?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t";
static char M_proto[] =
  "?f%f .?n?m(file %i of %m) ..?ltline %lt :byte %bB?s/%s ..?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t";
static char e_proto[] =
  "?f%f .?m(file %i of %m) .?ltline %lt .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t";

char *prproto[3];
char *eqproto = e_proto;

static char message[250];
static char *mp;

/*
 * Initialize the prompt prototype strings.
 */
	public void
init_prompt()
{
	prproto[0] = save(s_proto);
	prproto[1] = save(m_proto);
	prproto[2] = save(M_proto);
	eqproto = save(e_proto);
}

/*
 * Set the message pointer to the end of the message string.
 */
	static void
setmp()
{
	while (*mp != '\0')
		mp++;
}

/*
 * Append a POSITION (as a decimal integer) to the end of the message.
 */
	static void
ap_pos(pos)
	POSITION pos;
{
	(void)sprintf(mp, "%ld", (long)pos);
	setmp();
}

/*
 * Append an integer to the end of the message.
 */
	static void
ap_int(n)
	int n;
{
	(void)sprintf(mp, "%d", n);
	setmp();
}

/*
 * Append a question mark to the end of the message.
 */
	static void
ap_quest()
{
	*mp++ = '?';
}

/*
 * Return the "current" byte offset in the file.
 */
	static POSITION
curr_byte(where)
	int where;
{
	POSITION pos;

	pos = position(where);
	if (pos == NULL_POSITION)
		pos = ch_length();
	return (pos);
}

/*
 * Return the value of a prototype conditional.
 * A prototype string may include conditionals which consist of a 
 * question mark followed by a single letter.
 * Here we decode that letter and return the appropriate boolean value.
 */
	static int
cond(c, where)
	char c;
	int where;
{
	switch (c)
	{
	case 'a':	/* Anything in the message yet? */
		return (mp > message);
	case 'b':	/* Current byte offset known? */
		return (curr_byte(where) != NULL_POSITION);
	case 'e':	/* At end of file? */
		return (hit_eof);
	case 'f':	/* Filename known? */
		return (!ispipe);
	case 'l':	/* Line number known? */
		return (linenums);
	case 'm':	/* More than one file? */
		return (ac > 1);
	case 'n':	/* First prompt in a new file? */
		return (new_file);
	case 'p':	/* Percent into file known? */
		return (curr_byte(where) != NULL_POSITION && 
				ch_length() > 0);
	case 's':	/* Size of file known? */
		return (ch_length() != NULL_POSITION);
	case 'x':	/* Is there a "next" file? */
		return (curr_ac + 1 < ac);
	}
	return (0);
}

/*
 * Decode a "percent" prototype character.
 * A prototype string may include various "percent" escapes;
 * that is, a percent sign followed by a single letter.
 * Here we decode that letter and take the appropriate action,
 * usually by appending something to the message being built.
 */
	static void
protochar(c, where)
	int c;
	int where;
{
	POSITION pos;
	POSITION len;
	int n;

	switch (c)
	{
	case 'b':	/* Current byte offset */
		pos = curr_byte(where);
		if (pos != NULL_POSITION)
			ap_pos(pos);
		else
			ap_quest();
		break;
	case 'f':	/* File name */
		strtcpy(mp, current_file,
			(unsigned int)(&message[sizeof(message)] - mp));
		setmp();
		break;
	case 'i':	/* Index into list of files */
		ap_int(curr_ac + 1);
		break;
	case 'l':	/* Current line number */
		n = currline(where);
		if (n != 0)
			ap_int(n);
		else
			ap_quest();
		break;
	case 'm':	/* Number of files */
		ap_int(ac);
		break;
	case 'p':	/* Percent into file */
		pos = curr_byte(where);
		len = ch_length();
		if (pos != NULL_POSITION && len > 0)
			ap_int((int)(100*pos / len));
		else
			ap_quest();
		break;
	case 's':	/* Size of file */
		len = ch_length();
		if (len != NULL_POSITION)
			ap_pos(len);
		else
			ap_quest();
		break;
	case 't':	/* Truncate trailing spaces in the message */
		while (mp > message && mp[-1] == ' ')
			mp--;
		break;
	case 'x':	/* Name of next file */
		if (curr_ac + 1 < ac)
		{
			strtcpy(mp, av[curr_ac+1],
				(unsigned int)(&message[sizeof(message)] - mp));
			setmp();
		} else
			ap_quest();
		break;
	}
}

/*
 * Skip a false conditional.
 * When a false condition is found (either a false IF or the ELSE part 
 * of a true IF), this routine scans the prototype string to decide
 * where to resume parsing the string.
 * We must keep track of nested IFs and skip them properly.
 */
	static char *
skipcond(p)
	register char *p;
{
	register int iflevel = 1;

	for (;;) switch (*++p)
	{
	case '?':
		/*
		 * Start of a nested IF.
		 */
		iflevel++;
		break;
	case ':':
		/*
		 * Else.
		 * If this matches the IF we came in here with,
		 * then we're done.
		 */
		if (iflevel == 1)
			return (p);
		break;
	case '.':
		/*
		 * Endif.
		 * If this matches the IF we came in here with,
		 * then we're done.
		 */
		if (--iflevel == 0)
			return (p);
		break;
	case '\\':
		/*
		 * Backslash escapes the next character.
		 */
		++p;
		break;
	case '\0':
		/*
		 * Whoops.  Hit end of string.
		 * This is a malformed conditional, but just treat it
		 * as if all active conditionals ends here.
		 */
		return (p-1);
	}
	/*NOTREACHED*/
}

	static char *
wherechar(p, wp)
	char *p;
	int *wp;
{
	switch (*p)
	{
	case 'b': case 'l': case 'p':
		switch (*++p)
		{
		case 't':   *wp = TOP;			break;
		case 'm':   *wp = MIDDLE;		break;
		case 'b':   *wp = BOTTOM;		break;
		case 'B':   *wp = BOTTOM_PLUS_ONE;	break;
		default:    *wp = TOP;			break;
		}
	}
	return (p);
}

/*
 * Construct a message based on a prototype string.
 */
	static char *
pr_expand(proto, maxwidth)
	char *proto;
	int maxwidth;
{
	register char *p;
	register int c;
	int where;

	mp = message;

	if (*proto == '\0')
		return ("");

	for (p = proto;  *p != '\0';  p++)
	{
		switch (*p)
		{
		default:	/* Just put the character in the message */
			*mp++ = *p;
			break;
		case '\\':	/* Backslash escapes the next character */
			p++;
			*mp++ = *p;
			break;
		case '?':	/* Conditional (IF) */
			if ((c = *++p) == '\0')
				--p;
			else
			{
				p = wherechar(p, &where);
				if (!cond(c, where))
					p = skipcond(p);
			}
			break;
		case ':':	/* ELSE */
			p = skipcond(p);
			break;
		case '.':	/* ENDIF */
			break;
		case '%':	/* Percent escape */
			if ((c = *++p) == '\0')
				--p;
			else
			{
				p = wherechar(p, &where);
				protochar(c, where);
			}
			break;
		}
	}

	new_file = 0;
	if (mp == message)
		return (NULL);
	*mp = '\0';
	if (maxwidth > 0 && mp >= message + maxwidth)
	{
		/*
		 * Message is too long.
		 * Return just the final portion of it.
		 */
		return (mp - maxwidth);
	}
	return (message);
}

/*
 * Return a message suitable for printing by the "=" command.
 */
	public char *
eq_message()
{
	return (pr_expand(eqproto, 0));
}

/*
 * Return a prompt.
 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc.
 * If we can't come up with an appropriate prompt, return NULL
 * and the caller will prompt with a colon.
 */
	public char *
pr_string()
{
	return (pr_expand(prproto[pr_type], sc_width-so_width-se_width-2));
}
Commit	Line	Data
bfe13c81 KB	1	/*
	2	* Copyright (c) 1988 Mark Nudleman
	3	* Copyright (c) 1988 Regents of the University of California.
	4	* All rights reserved.
	5	*
bfe13c81 KB	6	* Redistribution and use in source and binary forms are permitted
	7	* provided that the above copyright notice and this paragraph are
	8	* duplicated in all such forms and that any documentation,
	9	* advertising materials, and other materials related to such
	10	* distribution and use acknowledge that the software was developed
a942b40b KB	11	* by Mark Nudleman and the University of California, Berkeley. The
a942b40b KB	12	* name of Mark Nudleman or the
bfe13c81 KB	13	* University may not be used to endorse or promote products derived
	14	* from this software without specific prior written permission.
	15	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	16	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	17	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	18	*/
	19
	20	#ifndef lint
a942b40b	21	static char sccsid[] = "@(#)prompt.c 5.4 (Berkeley) %G%";
bfe13c81 KB	22	#endif /* not lint */
	23
	24	/*
	25	* Prompting and other messages.
	26	* There are three flavors of prompts, SHORT, MEDIUM and LONG,
	27	* selected by the -m/-M options.
	28	* There is also the "equals message", printed by the = command.
	29	* A prompt is a message composed of various pieces, such as the
	30	* name of the file being viewed, the percentage into the file, etc.
	31	*/
	32
	33	#include "less.h"
	34	#include "position.h"
	35
	36	extern int pr_type;
	37	extern int ispipe;
	38	extern int hit_eof;
	39	extern int new_file;
	40	extern int sc_width;
	41	extern int so_width, se_width;
	42	extern char *current_file;
	43	extern int ac;
	44	extern char **av;
	45	extern int curr_ac;
	46	extern int linenums;
	47
	48	/*
	49	* Prototypes for the three flavors of prompts.
	50	* These strings are expanded by pr_expand().
	51	*/
	52	static char s_proto[] =
	53	"?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x..%t";
	54	static char m_proto[] =
	55	"?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t";
	56	static char M_proto[] =
	57	"?f%f .?n?m(file %i of %m) ..?ltline %lt :byte %bB?s/%s ..?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t";
	58	static char e_proto[] =
	59	"?f%f .?m(file %i of %m) .?ltline %lt .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t";
	60
	61	char *prproto[3];
	62	char *eqproto = e_proto;
	63
	64	static char message[250];
	65	static char *mp;
	66
	67	/*
	68	* Initialize the prompt prototype strings.
	69	*/
	70	public void
	71	init_prompt()
	72	{
	73	prproto[0] = save(s_proto);
	74	prproto[1] = save(m_proto);
	75	prproto[2] = save(M_proto);
	76	eqproto = save(e_proto);
	77	}
	78
	79	/*
	80	* Set the message pointer to the end of the message string.
	81	*/
	82	static void
	83	setmp()
	84	{
	85	while (*mp != '\0')
86	mp++;
87	}
88
89	/*
90	* Append a POSITION (as a decimal integer) to the end of the message.
91	*/
92	static void
93	ap_pos(pos)
94	POSITION pos;
95	{
8ef60375	96	(void)sprintf(mp, "%ld", (long)pos);
bfe13c81 KB	97	setmp();
	98	}
	99
	100	/*
	101	* Append an integer to the end of the message.
	102	*/
	103	static void
	104	ap_int(n)
	105	int n;
	106	{
8ef60375	107	(void)sprintf(mp, "%d", n);
bfe13c81 KB	108	setmp();
	109	}
	110
	111	/*
	112	* Append a question mark to the end of the message.
	113	*/
	114	static void
	115	ap_quest()
	116	{
	117	*mp++ = '?';
	118	}
	119
	120	/*
	121	* Return the "current" byte offset in the file.
	122	*/
	123	static POSITION
	124	curr_byte(where)
	125	int where;
	126	{
	127	POSITION pos;
	128
	129	pos = position(where);
	130	if (pos == NULL_POSITION)
	131	pos = ch_length();
	132	return (pos);
	133	}
	134
	135	/*
	136	* Return the value of a prototype conditional.
	137	* A prototype string may include conditionals which consist of a
	138	* question mark followed by a single letter.
	139	* Here we decode that letter and return the appropriate boolean value.
	140	*/
	141	static int
	142	cond(c, where)
	143	char c;
	144	int where;
	145	{
	146	switch (c)
	147	{
	148	case 'a': /* Anything in the message yet? */
	149	return (mp > message);
	150	case 'b': /* Current byte offset known? */
	151	return (curr_byte(where) != NULL_POSITION);
	152	case 'e': /* At end of file? */
	153	return (hit_eof);
	154	case 'f': /* Filename known? */
	155	return (!ispipe);
	156	case 'l': /* Line number known? */
	157	return (linenums);
	158	case 'm': /* More than one file? */
	159	return (ac > 1);
	160	case 'n': /* First prompt in a new file? */
	161	return (new_file);
	162	case 'p': /* Percent into file known? */
	163	return (curr_byte(where) != NULL_POSITION &&
	164	ch_length() > 0);
	165	case 's': /* Size of file known? */
	166	return (ch_length() != NULL_POSITION);
	167	case 'x': /* Is there a "next" file? */
	168	return (curr_ac + 1 < ac);
	169	}
	170	return (0);
	171	}
172
173	/*
174	* Decode a "percent" prototype character.
175	* A prototype string may include various "percent" escapes;
176	* that is, a percent sign followed by a single letter.
177	* Here we decode that letter and take the appropriate action,
178	* usually by appending something to the message being built.
179	*/
180	static void
181	protochar(c, where)
182	int c;
183	int where;
184	{
185	POSITION pos;
186	POSITION len;
187	int n;
188
189	switch (c)
190	{
191	case 'b': /* Current byte offset */
192	pos = curr_byte(where);
193	if (pos != NULL_POSITION)
194	ap_pos(pos);
195	else
196	ap_quest();
197	break;
198	case 'f': /* File name */
199	strtcpy(mp, current_file,
200	(unsigned int)(&message[sizeof(message)] - mp));
201	setmp();
202	break;
203	case 'i': /* Index into list of files */
204	ap_int(curr_ac + 1);
205	break;
206	case 'l': /* Current line number */
207	n = currline(where);
208	if (n != 0)
209	ap_int(n);
210	else
211	ap_quest();
212	break;
213	case 'm': /* Number of files */
214	ap_int(ac);
215	break;
216	case 'p': /* Percent into file */
217	pos = curr_byte(where);
218	len = ch_length();
219	if (pos != NULL_POSITION && len > 0)
220	ap_int((int)(100*pos / len));
221	else
222	ap_quest();
223	break;
224	case 's': /* Size of file */
225	len = ch_length();
226	if (len != NULL_POSITION)
227	ap_pos(len);
228	else
229	ap_quest();
230	break;
231	case 't': /* Truncate trailing spaces in the message */
232	while (mp > message && mp[-1] == ' ')
233	mp--;
234	break;
235	case 'x': /* Name of next file */
236	if (curr_ac + 1 < ac)
237	{
238	strtcpy(mp, av[curr_ac+1],
239	(unsigned int)(&message[sizeof(message)] - mp));
240	setmp();
241	} else
242	ap_quest();
243	break;
244	}
245	}
246
247	/*
248	* Skip a false conditional.
249	* When a false condition is found (either a false IF or the ELSE part
250	* of a true IF), this routine scans the prototype string to decide
251	* where to resume parsing the string.
252	* We must keep track of nested IFs and skip them properly.
253	*/
254	static char *
255	skipcond(p)
256	register char *p;
257	{
258	register int iflevel = 1;
259
260	for (;;) switch (*++p)
261	{
262	case '?':
263	/*
264	* Start of a nested IF.
265	*/
266	iflevel++;
267	break;
268	case ':':
269	/*
270	* Else.
271	* If this matches the IF we came in here with,
272	* then we're done.
273	*/
274	if (iflevel == 1)
275	return (p);
276	break;
277	case '.':
278	/*
279	* Endif.
280	* If this matches the IF we came in here with,
281	* then we're done.
282	*/
283	if (--iflevel == 0)
284	return (p);
285	break;
286	case '\\':
287	/*
288	* Backslash escapes the next character.
289	*/
290	++p;
291	break;
292	case '\0':
293	/*
294	* Whoops. Hit end of string.
295	* This is a malformed conditional, but just treat it
296	* as if all active conditionals ends here.
297	*/
298	return (p-1);
299	}
300	/NOTREACHED/
301	}
302
303	static char *
304	wherechar(p, wp)
305	char *p;
306	int *wp;
307	{
557a82ec	308	switch (*p)
bfe13c81 KB	309	{
	310	case 'b': case 'l': case 'p':
	311	switch (*++p)
	312	{
	313	case 't': *wp = TOP; break;
	314	case 'm': *wp = MIDDLE; break;
	315	case 'b': *wp = BOTTOM; break;
	316	case 'B': *wp = BOTTOM_PLUS_ONE; break;
	317	default: *wp = TOP; break;
	318	}
	319	}
	320	return (p);
	321	}
	322
	323	/*
	324	* Construct a message based on a prototype string.
	325	*/
	326	static char *
	327	pr_expand(proto, maxwidth)
	328	char *proto;
	329	int maxwidth;
	330	{
	331	register char *p;
	332	register int c;
	333	int where;
	334
	335	mp = message;
	336
	337	if (*proto == '\0')
	338	return ("");
	339
	340	for (p = proto; *p != '\0'; p++)
	341	{
	342	switch (*p)
	343	{
	344	default: /* Just put the character in the message */
	345	mp++ = p;
	346	break;
	347	case '\\': /* Backslash escapes the next character */
	348	p++;
	349	mp++ = p;
	350	break;
	351	case '?': /* Conditional (IF) */
	352	if ((c = *++p) == '\0')
	353	--p;
	354	else
	355	{
	356	p = wherechar(p, &where);
	357	if (!cond(c, where))
	358	p = skipcond(p);
	359	}
	360	break;
	361	case ':': /* ELSE */
	362	p = skipcond(p);
	363	break;
	364	case '.': /* ENDIF */
	365	break;
	366	case '%': /* Percent escape */
	367	if ((c = *++p) == '\0')
	368	--p;
	369	else
	370	{
	371	p = wherechar(p, &where);
	372	protochar(c, where);
373	}
374	break;
375	}
376	}
377
378	new_file = 0;
379	if (mp == message)
380	return (NULL);
381	*mp = '\0';
382	if (maxwidth > 0 && mp >= message + maxwidth)
383	{
384	/*
385	* Message is too long.
386	* Return just the final portion of it.
387	*/
388	return (mp - maxwidth);
389	}
390	return (message);
391	}
392
393	/*
394	* Return a message suitable for printing by the "=" command.
395	*/
396	public char *
397	eq_message()
398	{
399	return (pr_expand(eqproto, 0));
400	}
401
402	/*
403	* Return a prompt.
404	* This depends on the prompt type (SHORT, MEDIUM, LONG), etc.
405	* If we can't come up with an appropriate prompt, return NULL
406	* and the caller will prompt with a colon.
407	*/
408	public char *
409	pr_string()
410	{
411	return (pr_expand(prproto[pr_type], sc_width-so_width-se_width-2));
412	}