xref: /dragonfly/contrib/nvi2/vi/v_section.c (revision 7ff0fc30)
1 /*-
2  * Copyright (c) 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
5  *	Keith Bostic.  All rights reserved.
6  *
7  * See the LICENSE file for redistribution information.
8  */
9 
10 #include "config.h"
11 
12 #include <sys/types.h>
13 #include <sys/queue.h>
14 #include <sys/time.h>
15 
16 #include <bitstring.h>
17 #include <limits.h>
18 #include <stdio.h>
19 #include <string.h>
20 
21 #include "../common/common.h"
22 #include "vi.h"
23 
24 /*
25  * !!!
26  * In historic vi, the section commands ignored empty lines, unlike the
27  * paragraph commands, which was probably okay.  However, they also moved
28  * to the start of the last line when there where no more sections instead
29  * of the end of the last line like the paragraph commands.  I've changed
30  * the latter behavior to match the paragraph commands.
31  *
32  * In historic vi, a section was defined as the first character(s) of the
33  * line matching, which could be followed by anything.  This implementation
34  * follows that historic practice.
35  *
36  * !!!
37  * The historic vi documentation (USD:15-10) claimed:
38  *	The section commands interpret a preceding count as a different
39  *	window size in which to redraw the screen at the new location,
40  *	and this window size is the base size for newly drawn windows
41  *	until another size is specified.  This is very useful if you are
42  *	on a slow terminal ...
43  *
44  * I can't get the 4BSD vi to do this, it just beeps at me.  For now, a
45  * count to the section commands simply repeats the command.
46  */
47 
48 /*
49  * v_sectionf -- [count]]]
50  *	Move forward count sections/functions.
51  *
52  * !!!
53  * Using ]] as a motion command was a bit special, historically.  It could
54  * match } as well as the usual { and section values.  If it matched a { or
55  * a section, it did NOT include the matched line.  If it matched a }, it
56  * did include the line.  No clue why.
57  *
58  * PUBLIC: int v_sectionf(SCR *, VICMD *);
59  */
60 int
61 v_sectionf(SCR *sp, VICMD *vp)
62 {
63 	recno_t cnt, lno;
64 	size_t len;
65 	CHAR_T *p;
66 	char *list, *lp;
67 
68 	/* Get the macro list. */
69 	if ((list = O_STR(sp, O_SECTIONS)) == NULL)
70 		return (1);
71 
72 	/*
73 	 * !!!
74 	 * If the starting cursor position is at or before any non-blank
75 	 * characters in the line, i.e. the movement is cutting all of the
76 	 * line's text, the buffer is in line mode.  It's a lot easier to
77 	 * check here, because we know that the end is going to be the start
78 	 * or end of a line.
79 	 */
80 	if (ISMOTION(vp))
81 		if (vp->m_start.cno == 0)
82 			F_SET(vp, VM_LMODE);
83 		else {
84 			vp->m_stop = vp->m_start;
85 			vp->m_stop.cno = 0;
86 			if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
87 				return (1);
88 			if (vp->m_start.cno <= vp->m_stop.cno)
89 				F_SET(vp, VM_LMODE);
90 		}
91 
92 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
93 	for (lno = vp->m_start.lno; !db_get(sp, ++lno, 0, &p, &len);) {
94 		if (len == 0)
95 			continue;
96 		if (p[0] == '{' || (ISMOTION(vp) && p[0] == '}')) {
97 			if (!--cnt) {
98 				if (p[0] == '{')
99 					goto adjust1;
100 				goto adjust2;
101 			}
102 			continue;
103 		}
104 		/*
105 		 * !!!
106 		 * Historic documentation (USD:15-11, 4.2) said that formfeed
107 		 * characters (^L) in the first column delimited sections.
108 		 * The historic code mentions formfeed characters, but never
109 		 * implements them.  Seems reasonable, do it.
110 		 */
111 		if (p[0] == '\014') {
112 			if (!--cnt)
113 				goto adjust1;
114 			continue;
115 		}
116 		if (p[0] != '.' || len < 2)
117 			continue;
118 		for (lp = list; *lp != '\0'; lp += 2 * sizeof(*lp))
119 			if (lp[0] == p[1] &&
120 			    ((lp[1] == ' ' && len == 2) || lp[1] == p[2]) &&
121 			    !--cnt) {
122 				/*
123 				 * !!!
124 				 * If not cutting this line, adjust to the end
125 				 * of the previous one.  Otherwise, position to
126 				 * column 0.
127 				 */
128 adjust1:			if (ISMOTION(vp))
129 					goto ret1;
130 
131 adjust2:			vp->m_stop.lno = lno;
132 				vp->m_stop.cno = 0;
133 				goto ret2;
134 			}
135 	}
136 
137 	/* If moving forward, reached EOF, check to see if we started there. */
138 	if (vp->m_start.lno == lno - 1) {
139 		v_eof(sp, NULL);
140 		return (1);
141 	}
142 
143 ret1:	if (db_get(sp, --lno, DBG_FATAL, NULL, &len))
144 		return (1);
145 	vp->m_stop.lno = lno;
146 	vp->m_stop.cno = len ? len - 1 : 0;
147 
148 	/*
149 	 * Non-motion commands go to the end of the range.  Delete and
150 	 * yank stay at the start of the range.  Ignore others.
151 	 */
152 ret2:	if (ISMOTION(vp)) {
153 		vp->m_final = vp->m_start;
154 		if (F_ISSET(vp, VM_LMODE))
155 			vp->m_final.cno = 0;
156 	} else
157 		vp->m_final = vp->m_stop;
158 	return (0);
159 }
160 
161 /*
162  * v_sectionb -- [count][[
163  *	Move backward count sections/functions.
164  *
165  * PUBLIC: int v_sectionb(SCR *, VICMD *);
166  */
167 int
168 v_sectionb(SCR *sp, VICMD *vp)
169 {
170 	size_t len;
171 	recno_t cnt, lno;
172 	CHAR_T *p;
173 	char *list, *lp;
174 
175 	/* An empty file or starting from line 1 is always illegal. */
176 	if (vp->m_start.lno <= 1) {
177 		v_sof(sp, NULL);
178 		return (1);
179 	}
180 
181 	/* Get the macro list. */
182 	if ((list = O_STR(sp, O_SECTIONS)) == NULL)
183 		return (1);
184 
185 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
186 	for (lno = vp->m_start.lno; !db_get(sp, --lno, 0, &p, &len);) {
187 		if (len == 0)
188 			continue;
189 		if (p[0] == '{') {
190 			if (!--cnt)
191 				goto adjust1;
192 			continue;
193 		}
194 		/*
195 		 * !!!
196 		 * Historic documentation (USD:15-11, 4.2) said that formfeed
197 		 * characters (^L) in the first column delimited sections.
198 		 * The historic code mentions formfeed characters, but never
199 		 * implements them.  Seems reasonable, do it.
200 		 */
201 		if (p[0] == '\014') {
202 			if (!--cnt)
203 				goto adjust1;
204 			continue;
205 		}
206 		if (p[0] != '.' || len < 2)
207 			continue;
208 		for (lp = list; *lp != '\0'; lp += 2 * sizeof(*lp))
209 			if (lp[0] == p[1] &&
210 			    ((lp[1] == ' ' && len == 2) || lp[1] == p[2]) &&
211 			    !--cnt) {
212 adjust1:			vp->m_stop.lno = lno;
213 				vp->m_stop.cno = 0;
214 				goto ret1;
215 			}
216 	}
217 
218 	/*
219 	 * If moving backward, reached SOF, which is a movement sink.
220 	 * We already checked for starting there.
221 	 */
222 	vp->m_stop.lno = 1;
223 	vp->m_stop.cno = 0;
224 
225 	/*
226 	 * All commands move to the end of the range.
227 	 *
228 	 * !!!
229 	 * Historic practice is the section cut was in line mode if it started
230 	 * from column 0 and was in the backward direction.  Otherwise, left
231 	 * motion commands adjust the starting point to the character before
232 	 * the current one.  What makes this worse is that if it cut to line
233 	 * mode it also went to the first non-<blank>.
234 	 */
235 ret1:	if (vp->m_start.cno == 0) {
236 		F_CLR(vp, VM_RCM_MASK);
237 		F_SET(vp, VM_RCM_SETFNB);
238 
239 		--vp->m_start.lno;
240 		F_SET(vp, VM_LMODE);
241 	} else
242 		--vp->m_start.cno;
243 
244 	vp->m_final = vp->m_stop;
245 	return (0);
246 }
247