1/*	$NetBSD: v_section.c,v 1.3 2014/01/26 21:43:45 christos Exp $ */
2/*-
3 * Copyright (c) 1992, 1993, 1994
4 *	The Regents of the University of California.  All rights reserved.
5 * Copyright (c) 1992, 1993, 1994, 1995, 1996
6 *	Keith Bostic.  All rights reserved.
7 *
8 * See the LICENSE file for redistribution information.
9 */
10
11#include "config.h"
12
13#include <sys/cdefs.h>
14#if 0
15#ifndef lint
16static const char sccsid[] = "Id: v_section.c,v 10.10 2001/06/25 15:19:35 skimo Exp  (Berkeley) Date: 2001/06/25 15:19:35 ";
17#endif /* not lint */
18#else
19__RCSID("$NetBSD: v_section.c,v 1.3 2014/01/26 21:43:45 christos Exp $");
20#endif
21
22#include <sys/types.h>
23#include <sys/queue.h>
24#include <sys/time.h>
25
26#include <bitstring.h>
27#include <limits.h>
28#include <stdio.h>
29#include <string.h>
30
31#include "../common/common.h"
32#include "vi.h"
33
34/*
35 * !!!
36 * In historic vi, the section commands ignored empty lines, unlike the
37 * paragraph commands, which was probably okay.  However, they also moved
38 * to the start of the last line when there where no more sections instead
39 * of the end of the last line like the paragraph commands.  I've changed
40 * the latter behavior to match the paragraph commands.
41 *
42 * In historic vi, a section was defined as the first character(s) of the
43 * line matching, which could be followed by anything.  This implementation
44 * follows that historic practice.
45 *
46 * !!!
47 * The historic vi documentation (USD:15-10) claimed:
48 *	The section commands interpret a preceding count as a different
49 *	window size in which to redraw the screen at the new location,
50 *	and this window size is the base size for newly drawn windows
51 *	until another size is specified.  This is very useful if you are
52 *	on a slow terminal ...
53 *
54 * I can't get the 4BSD vi to do this, it just beeps at me.  For now, a
55 * count to the section commands simply repeats the command.
56 */
57
58/*
59 * v_sectionf -- [count]]]
60 *	Move forward count sections/functions.
61 *
62 * !!!
63 * Using ]] as a motion command was a bit special, historically.  It could
64 * match } as well as the usual { and section values.  If it matched a { or
65 * a section, it did NOT include the matched line.  If it matched a }, it
66 * did include the line.  No clue why.
67 *
68 * PUBLIC: int v_sectionf __P((SCR *, VICMD *));
69 */
70int
71v_sectionf(SCR *sp, VICMD *vp)
72{
73	db_recno_t cnt, lno;
74	size_t len;
75	CHAR_T *p;
76	const char *list, *lp;
77
78	/* Get the macro list. */
79	if ((list = O_STR(sp, O_SECTIONS)) == NULL)
80		return (1);
81
82	/*
83	 * !!!
84	 * If the starting cursor position is at or before any non-blank
85	 * characters in the line, i.e. the movement is cutting all of the
86	 * line's text, the buffer is in line mode.  It's a lot easier to
87	 * check here, because we know that the end is going to be the start
88	 * or end of a line.
89	 */
90	if (ISMOTION(vp)) {
91		if (vp->m_start.cno == 0)
92			F_SET(vp, VM_LMODE);
93		else {
94			vp->m_stop = vp->m_start;
95			vp->m_stop.cno = 0;
96			if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
97				return (1);
98			if (vp->m_start.cno <= vp->m_stop.cno)
99				F_SET(vp, VM_LMODE);
100		}
101	}
102
103	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
104	for (lno = vp->m_start.lno; !db_get(sp, ++lno, 0, &p, &len);) {
105		if (len == 0)
106			continue;
107		if (p[0] == '{' || (ISMOTION(vp) && p[0] == '}')) {
108			if (!--cnt) {
109				if (p[0] == '{')
110					goto adjust1;
111				goto adjust2;
112			}
113			continue;
114		}
115		/*
116		 * !!!
117		 * Historic documentation (USD:15-11, 4.2) said that formfeed
118		 * characters (^L) in the first column delimited sections.
119		 * The historic code mentions formfeed characters, but never
120		 * implements them.  Seems reasonable, do it.
121		 */
122		if (p[0] == '\014') {
123			if (!--cnt)
124				goto adjust1;
125			continue;
126		}
127		if (p[0] != '.' || len < 2)
128			continue;
129		for (lp = list; *lp != '\0'; lp += 2 * sizeof(*lp))
130			if (lp[0] == p[1] &&
131			    ((lp[1] == ' ' && len == 2) || lp[1] == p[2]) &&
132			    !--cnt) {
133				/*
134				 * !!!
135				 * If not cutting this line, adjust to the end
136				 * of the previous one.  Otherwise, position to
137				 * column 0.
138				 */
139adjust1:			if (ISMOTION(vp))
140					goto ret1;
141
142adjust2:			vp->m_stop.lno = lno;
143				vp->m_stop.cno = 0;
144				goto ret2;
145			}
146	}
147
148	/* If moving forward, reached EOF, check to see if we started there. */
149	if (vp->m_start.lno == lno - 1) {
150		v_eof(sp, NULL);
151		return (1);
152	}
153
154ret1:	if (db_get(sp, --lno, DBG_FATAL, NULL, &len))
155		return (1);
156	vp->m_stop.lno = lno;
157	vp->m_stop.cno = len ? len - 1 : 0;
158
159	/*
160	 * Non-motion commands go to the end of the range.  Delete and
161	 * yank stay at the start of the range.  Ignore others.
162	 */
163ret2:	if (ISMOTION(vp)) {
164		vp->m_final = vp->m_start;
165		if (F_ISSET(vp, VM_LMODE))
166			vp->m_final.cno = 0;
167	} else
168		vp->m_final = vp->m_stop;
169	return (0);
170}
171
172/*
173 * v_sectionb -- [count][[
174 *	Move backward count sections/functions.
175 *
176 * PUBLIC: int v_sectionb __P((SCR *, VICMD *));
177 */
178int
179v_sectionb(SCR *sp, VICMD *vp)
180{
181	size_t len;
182	db_recno_t cnt, lno;
183	CHAR_T *p;
184	const char *list, *lp;
185
186	/* An empty file or starting from line 1 is always illegal. */
187	if (vp->m_start.lno <= 1) {
188		v_sof(sp, NULL);
189		return (1);
190	}
191
192	/* Get the macro list. */
193	if ((list = O_STR(sp, O_SECTIONS)) == NULL)
194		return (1);
195
196	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
197	for (lno = vp->m_start.lno; !db_get(sp, --lno, 0, &p, &len);) {
198		if (len == 0)
199			continue;
200		if (p[0] == '{') {
201			if (!--cnt)
202				goto adjust1;
203			continue;
204		}
205		/*
206		 * !!!
207		 * Historic documentation (USD:15-11, 4.2) said that formfeed
208		 * characters (^L) in the first column delimited sections.
209		 * The historic code mentions formfeed characters, but never
210		 * implements them.  Seems reasonable, do it.
211		 */
212		if (p[0] == '\014') {
213			if (!--cnt)
214				goto adjust1;
215			continue;
216		}
217		if (p[0] != '.' || len < 2)
218			continue;
219		for (lp = list; *lp != '\0'; lp += 2 * sizeof(*lp))
220			if (lp[0] == p[1] &&
221			    ((lp[1] == ' ' && len == 2) || lp[1] == p[2]) &&
222			    !--cnt) {
223adjust1:			vp->m_stop.lno = lno;
224				vp->m_stop.cno = 0;
225				goto ret1;
226			}
227	}
228
229	/*
230	 * If moving backward, reached SOF, which is a movement sink.
231	 * We already checked for starting there.
232	 */
233	vp->m_stop.lno = 1;
234	vp->m_stop.cno = 0;
235
236	/*
237	 * All commands move to the end of the range.
238	 *
239	 * !!!
240	 * Historic practice is the section cut was in line mode if it started
241	 * from column 0 and was in the backward direction.  Otherwise, left
242	 * motion commands adjust the starting point to the character before
243	 * the current one.  What makes this worse is that if it cut to line
244	 * mode it also went to the first non-<blank>.
245	 */
246ret1:	if (vp->m_start.cno == 0) {
247		F_CLR(vp, VM_RCM_MASK);
248		F_SET(vp, VM_RCM_SETFNB);
249
250		--vp->m_start.lno;
251		F_SET(vp, VM_LMODE);
252	} else
253		--vp->m_start.cno;
254
255	vp->m_final = vp->m_stop;
256	return (0);
257}
258