[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.
 *
 * This code is derived from software contributed to Berkeley by
 * Mark Nudleman.
 * 
 * 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 the University of California, Berkeley.  The name of 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	5.1 (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;
{
	sprintf(mp, "%ld", (long)pos);
	setmp();
}

/*
 * Append an integer to the end of the message.
 */
	static void
ap_int(n)
	int n;
{
	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;
{
	int c;

	switch (c = *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	*
	6	* This code is derived from software contributed to Berkeley by
	7	* Mark Nudleman.
	8	*
	9	* Redistribution and use in source and binary forms are permitted
	10	* provided that the above copyright notice and this paragraph are
	11	* duplicated in all such forms and that any documentation,
	12	* advertising materials, and other materials related to such
	13	* distribution and use acknowledge that the software was developed
	14	* by the University of California, Berkeley. The name of the
	15	* University may not be used to endorse or promote products derived
	16	* from this software without specific prior written permission.
	17	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	18	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	19	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	20	*/
	21
	22	#ifndef lint
	23	static char sccsid[] = "@(#)prompt.c 5.1 (Berkeley) %G%";
	24	#endif /* not lint */
	25
	26	/*
	27	* Prompting and other messages.
	28	* There are three flavors of prompts, SHORT, MEDIUM and LONG,
	29	* selected by the -m/-M options.
	30	* There is also the "equals message", printed by the = command.
	31	* A prompt is a message composed of various pieces, such as the
	32	* name of the file being viewed, the percentage into the file, etc.
	33	*/
	34
	35	#include "less.h"
	36	#include "position.h"
	37
	38	extern int pr_type;
	39	extern int ispipe;
	40	extern int hit_eof;
	41	extern int new_file;
	42	extern int sc_width;
	43	extern int so_width, se_width;
	44	extern char *current_file;
	45	extern int ac;
	46	extern char **av;
	47	extern int curr_ac;
	48	extern int linenums;
	49
	50	/*
	51	* Prototypes for the three flavors of prompts.
	52	* These strings are expanded by pr_expand().
	53	*/
	54	static char s_proto[] =
	55	"?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x..%t";
	56	static char m_proto[] =
	57	"?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t";
	58	static char M_proto[] =
	59	"?f%f .?n?m(file %i of %m) ..?ltline %lt :byte %bB?s/%s ..?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t";
	60	static char e_proto[] =
	61	"?f%f .?m(file %i of %m) .?ltline %lt .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t";
	62
	63	char *prproto[3];
	64	char *eqproto = e_proto;
65
66	static char message[250];
67	static char *mp;
68
69	/*
70	* Initialize the prompt prototype strings.
71	*/
72	public void
73	init_prompt()
74	{
75	prproto[0] = save(s_proto);
76	prproto[1] = save(m_proto);
77	prproto[2] = save(M_proto);
78	eqproto = save(e_proto);
79	}
80
81	/*
82	* Set the message pointer to the end of the message string.
83	*/
84	static void
85	setmp()
86	{
87	while (*mp != '\0')
88	mp++;
89	}
90
91	/*
92	* Append a POSITION (as a decimal integer) to the end of the message.
93	*/
94	static void
95	ap_pos(pos)
96	POSITION pos;
97	{
98	sprintf(mp, "%ld", (long)pos);
99	setmp();
100	}
101
102	/*
103	* Append an integer to the end of the message.
104	*/
105	static void
106	ap_int(n)
107	int n;
108	{
109	sprintf(mp, "%d", n);
110	setmp();
111	}
112
113	/*
114	* Append a question mark to the end of the message.
115	*/
116	static void
117	ap_quest()
118	{
119	*mp++ = '?';
120	}
121
122	/*
123	* Return the "current" byte offset in the file.
124	*/
125	static POSITION
126	curr_byte(where)
127	int where;
128	{
129	POSITION pos;
130
131	pos = position(where);
132	if (pos == NULL_POSITION)
133	pos = ch_length();
134	return (pos);
135	}
136
137	/*
138	* Return the value of a prototype conditional.
139	* A prototype string may include conditionals which consist of a
140	* question mark followed by a single letter.
141	* Here we decode that letter and return the appropriate boolean value.
142	*/
143	static int
144	cond(c, where)
145	char c;
146	int where;
147	{
148	switch (c)
149	{
150	case 'a': /* Anything in the message yet? */
151	return (mp > message);
152	case 'b': /* Current byte offset known? */
153	return (curr_byte(where) != NULL_POSITION);
154	case 'e': /* At end of file? */
155	return (hit_eof);
156	case 'f': /* Filename known? */
157	return (!ispipe);
158	case 'l': /* Line number known? */
159	return (linenums);
160	case 'm': /* More than one file? */
161	return (ac > 1);
162	case 'n': /* First prompt in a new file? */
163	return (new_file);
164	case 'p': /* Percent into file known? */
165	return (curr_byte(where) != NULL_POSITION &&
166	ch_length() > 0);
167	case 's': /* Size of file known? */
168	return (ch_length() != NULL_POSITION);
169	case 'x': /* Is there a "next" file? */
170	return (curr_ac + 1 < ac);
171	}
172	return (0);
173	}
174
175	/*
176	* Decode a "percent" prototype character.
177	* A prototype string may include various "percent" escapes;
178	* that is, a percent sign followed by a single letter.
179	* Here we decode that letter and take the appropriate action,
180	* usually by appending something to the message being built.
181	*/
182	static void
183	protochar(c, where)
184	int c;
185	int where;
186	{
187	POSITION pos;
188	POSITION len;
189	int n;
190
191	switch (c)
192	{
193	case 'b': /* Current byte offset */
194	pos = curr_byte(where);
195	if (pos != NULL_POSITION)
196	ap_pos(pos);
197	else
198	ap_quest();
199	break;
200	case 'f': /* File name */
201	strtcpy(mp, current_file,
202	(unsigned int)(&message[sizeof(message)] - mp));
203	setmp();
204	break;
205	case 'i': /* Index into list of files */
206	ap_int(curr_ac + 1);
207	break;
208	case 'l': /* Current line number */
209	n = currline(where);
210	if (n != 0)
211	ap_int(n);
212	else
213	ap_quest();
214	break;
215	case 'm': /* Number of files */
216	ap_int(ac);
217	break;
218	case 'p': /* Percent into file */
219	pos = curr_byte(where);
220	len = ch_length();
221	if (pos != NULL_POSITION && len > 0)
222	ap_int((int)(100*pos / len));
223	else
224	ap_quest();
225	break;
226	case 's': /* Size of file */
227	len = ch_length();
228	if (len != NULL_POSITION)
229	ap_pos(len);
230	else
231	ap_quest();
232	break;
233	case 't': /* Truncate trailing spaces in the message */
234	while (mp > message && mp[-1] == ' ')
235	mp--;
236	break;
237	case 'x': /* Name of next file */
238	if (curr_ac + 1 < ac)
239	{
240	strtcpy(mp, av[curr_ac+1],
241	(unsigned int)(&message[sizeof(message)] - mp));
242	setmp();
243	} else
244	ap_quest();
245	break;
246	}
247	}
248
249	/*
250	* Skip a false conditional.
251	* When a false condition is found (either a false IF or the ELSE part
252	* of a true IF), this routine scans the prototype string to decide
253	* where to resume parsing the string.
254	* We must keep track of nested IFs and skip them properly.
255	*/
256	static char *
257	skipcond(p)
258	register char *p;
259	{
260	register int iflevel = 1;
261
262	for (;;) switch (*++p)
263	{
264	case '?':
265	/*
266	* Start of a nested IF.
267	*/
268	iflevel++;
269	break;
270	case ':':
271	/*
272	* Else.
273	* If this matches the IF we came in here with,
274	* then we're done.
275	*/
276	if (iflevel == 1)
277	return (p);
278	break;
279	case '.':
280	/*
281	* Endif.
282	* If this matches the IF we came in here with,
283	* then we're done.
284	*/
285	if (--iflevel == 0)
286	return (p);
287	break;
288	case '\\':
289	/*
290	* Backslash escapes the next character.
291	*/
292	++p;
293	break;
294	case '\0':
295	/*
296	* Whoops. Hit end of string.
297	* This is a malformed conditional, but just treat it
298	* as if all active conditionals ends here.
299	*/
300	return (p-1);
301	}
302	/NOTREACHED/
303	}
304
305	static char *
306	wherechar(p, wp)
307	char *p;
308	int *wp;
309	{
310	int c;
311
312	switch (c = *p)
313	{
314	case 'b': case 'l': case 'p':
315	switch (*++p)
316	{
317	case 't': *wp = TOP; break;
318	case 'm': *wp = MIDDLE; break;
319	case 'b': *wp = BOTTOM; break;
320	case 'B': *wp = BOTTOM_PLUS_ONE; break;
321	default: *wp = TOP; break;
322	}
323	}
324	return (p);
325	}
326
327	/*
328	* Construct a message based on a prototype string.
329	*/
330	static char *
331	pr_expand(proto, maxwidth)
332	char *proto;
333	int maxwidth;
334	{
335	register char *p;
336	register int c;
337	int where;
338
339	mp = message;
340
341	if (*proto == '\0')
342	return ("");
343
344	for (p = proto; *p != '\0'; p++)
345	{
346	switch (*p)
347	{
348	default: /* Just put the character in the message */
349	mp++ = p;
350	break;
351	case '\\': /* Backslash escapes the next character */
352	p++;
353	mp++ = p;
354	break;
355	case '?': /* Conditional (IF) */
356	if ((c = *++p) == '\0')
357	--p;
358	else
359	{
360	p = wherechar(p, &where);
361	if (!cond(c, where))
362	p = skipcond(p);
363	}
364	break;
365	case ':': /* ELSE */
366	p = skipcond(p);
367	break;
368	case '.': /* ENDIF */
369	break;
370	case '%': /* Percent escape */
371	if ((c = *++p) == '\0')
372	--p;
373	else
374	{
375	p = wherechar(p, &where);
376	protochar(c, where);
377	}
378	break;
379	}
380	}
381
382	new_file = 0;
383	if (mp == message)
384	return (NULL);
385	*mp = '\0';
386	if (maxwidth > 0 && mp >= message + maxwidth)
387	{
388	/*
389	* Message is too long.
390	* Return just the final portion of it.
391	*/
392	return (mp - maxwidth);
393	}
394	return (message);
395	}
396
397	/*
398	* Return a message suitable for printing by the "=" command.
399	*/
400	public char *
401	eq_message()
402	{
403	return (pr_expand(eqproto, 0));
404	}
405
406	/*
407	* Return a prompt.
408	* This depends on the prompt type (SHORT, MEDIUM, LONG), etc.
409	* If we can't come up with an appropriate prompt, return NULL
410	* and the caller will prompt with a colon.
411	*/
412	public char *
413	pr_string()
414	{
415	return (pr_expand(prproto[pr_type], sc_width-so_width-se_width-2));
416	}