xref: /freebsd/contrib/nvi/vi/v_left.c (revision 7431dfd4580e850375fe5478d92ec770344db098)
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 #ifndef lint
13 static const char sccsid[] = "$Id: v_left.c,v 10.9 2001/06/25 15:19:32 skimo Exp $";
14 #endif /* not lint */
15 
16 #include <sys/types.h>
17 #include <sys/queue.h>
18 #include <sys/time.h>
19 
20 #include <bitstring.h>
21 #include <limits.h>
22 #include <stdio.h>
23 
24 #include "../common/common.h"
25 #include "vi.h"
26 
27 /*
28  * v_left -- [count]^H, [count]h
29  *	Move left by columns.
30  *
31  * PUBLIC: int v_left __P((SCR *, VICMD *));
32  */
33 int
34 v_left(SCR *sp, VICMD *vp)
35 {
36 	recno_t cnt;
37 
38 	/*
39 	 * !!!
40 	 * The ^H and h commands always failed in the first column.
41 	 */
42 	if (vp->m_start.cno == 0) {
43 		v_sol(sp);
44 		return (1);
45 	}
46 
47 	/* Find the end of the range. */
48 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
49 	if (vp->m_start.cno > cnt)
50 		vp->m_stop.cno = vp->m_start.cno - cnt;
51 	else
52 		vp->m_stop.cno = 0;
53 
54 	/*
55 	 * All commands move to the end of the range.  Motion commands
56 	 * adjust the starting point to the character before the current
57 	 * one.
58 	 */
59 	if (ISMOTION(vp))
60 		--vp->m_start.cno;
61 	vp->m_final = vp->m_stop;
62 	return (0);
63 }
64 
65 /*
66  * v_cfirst -- [count]_
67  *	Move to the first non-blank character in a line.
68  *
69  * PUBLIC: int v_cfirst __P((SCR *, VICMD *));
70  */
71 int
72 v_cfirst(SCR *sp, VICMD *vp)
73 {
74 	recno_t cnt, lno;
75 
76 	/*
77 	 * !!!
78 	 * If the _ is a motion component, it makes the command a line motion
79 	 * e.g. "d_" deletes the line.  It also means that the cursor doesn't
80 	 * move.
81 	 *
82 	 * The _ command never failed in the first column.
83 	 */
84 	if (ISMOTION(vp))
85 		F_SET(vp, VM_LMODE);
86 	/*
87 	 * !!!
88 	 * Historically a specified count makes _ move down count - 1
89 	 * rows, so, "3_" is the same as "2j_".
90 	 */
91 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
92 	if (cnt != 1) {
93 		--vp->count;
94 		return (v_down(sp, vp));
95 	}
96 
97 	/*
98 	 * Move to the first non-blank.
99 	 *
100 	 * Can't just use RCM_SET_FNB, in case _ is used as the motion
101 	 * component of another command.
102 	 */
103 	vp->m_stop.cno = 0;
104 	if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
105 		return (1);
106 
107 	/*
108 	 * !!!
109 	 * The _ command has to fail if the file is empty and we're doing
110 	 * a delete.  If deleting line 1, and 0 is the first nonblank,
111 	 * make the check.
112 	 */
113 	if (vp->m_stop.lno == 1 &&
114 	    vp->m_stop.cno == 0 && ISCMD(vp->rkp, 'd')) {
115 		if (db_last(sp, &lno))
116 			return (1);
117 		if (lno == 0) {
118 			v_sol(sp);
119 			return (1);
120 		}
121 	}
122 
123 	/*
124 	 * Delete and non-motion commands move to the end of the range,
125 	 * yank stays at the start.  Ignore others.
126 	 */
127 	vp->m_final =
128 	    ISMOTION(vp) && ISCMD(vp->rkp, 'y') ? vp->m_start : vp->m_stop;
129 	return (0);
130 }
131 
132 /*
133  * v_first -- ^
134  *	Move to the first non-blank character in this line.
135  *
136  * PUBLIC: int v_first __P((SCR *, VICMD *));
137  */
138 int
139 v_first(SCR *sp, VICMD *vp)
140 {
141 	/*
142 	 * !!!
143 	 * Yielding to none in our quest for compatibility with every
144 	 * historical blemish of vi, no matter how strange it might be,
145 	 * we permit the user to enter a count and then ignore it.
146 	 */
147 
148 	/*
149 	 * Move to the first non-blank.
150 	 *
151 	 * Can't just use RCM_SET_FNB, in case ^ is used as the motion
152 	 * component of another command.
153 	 */
154 	vp->m_stop.cno = 0;
155 	if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
156 		return (1);
157 
158 	/*
159 	 * !!!
160 	 * The ^ command succeeded if used as a command when the cursor was
161 	 * on the first non-blank in the line, but failed if used as a motion
162 	 * component in the same situation.
163 	 */
164 	if (ISMOTION(vp) && vp->m_start.cno == vp->m_stop.cno) {
165 		v_sol(sp);
166 		return (1);
167 	}
168 
169 	/*
170 	 * If moving right, non-motion commands move to the end of the range.
171 	 * Delete and yank stay at the start.  Motion commands adjust the
172 	 * ending point to the character before the current ending charcter.
173 	 *
174 	 * If moving left, all commands move to the end of the range.  Motion
175 	 * commands adjust the starting point to the character before the
176 	 * current starting character.
177 	 */
178 	if (vp->m_start.cno < vp->m_stop.cno)
179 		if (ISMOTION(vp)) {
180 			--vp->m_stop.cno;
181 			vp->m_final = vp->m_start;
182 		} else
183 			vp->m_final = vp->m_stop;
184 	else {
185 		if (ISMOTION(vp))
186 			--vp->m_start.cno;
187 		vp->m_final = vp->m_stop;
188 	}
189 	return (0);
190 }
191 
192 /*
193  * v_ncol -- [count]|
194  *	Move to column count or the first column on this line.  If the
195  *	requested column is past EOL, move to EOL.  The nasty part is
196  *	that we have to know character column widths to make this work.
197  *
198  * PUBLIC: int v_ncol __P((SCR *, VICMD *));
199  */
200 int
201 v_ncol(SCR *sp, VICMD *vp)
202 {
203 	if (F_ISSET(vp, VC_C1SET) && vp->count > 1) {
204 		--vp->count;
205 		vp->m_stop.cno =
206 		    vs_colpos(sp, vp->m_start.lno, (size_t)vp->count);
207 		/*
208 		 * !!!
209 		 * The | command succeeded if used as a command and the cursor
210 		 * didn't move, but failed if used as a motion component in the
211 		 * same situation.
212 		 */
213 		if (ISMOTION(vp) && vp->m_stop.cno == vp->m_start.cno) {
214 			v_nomove(sp);
215 			return (1);
216 		}
217 	} else {
218 		/*
219 		 * !!!
220 		 * The | command succeeded if used as a command in column 0
221 		 * without a count, but failed if used as a motion component
222 		 * in the same situation.
223 		 */
224 		if (ISMOTION(vp) && vp->m_start.cno == 0) {
225 			v_sol(sp);
226 			return (1);
227 		}
228 		vp->m_stop.cno = 0;
229 	}
230 
231 	/*
232 	 * If moving right, non-motion commands move to the end of the range.
233 	 * Delete and yank stay at the start.  Motion commands adjust the
234 	 * ending point to the character before the current ending charcter.
235 	 *
236 	 * If moving left, all commands move to the end of the range.  Motion
237 	 * commands adjust the starting point to the character before the
238 	 * current starting character.
239 	 */
240 	if (vp->m_start.cno < vp->m_stop.cno)
241 		if (ISMOTION(vp)) {
242 			--vp->m_stop.cno;
243 			vp->m_final = vp->m_start;
244 		} else
245 			vp->m_final = vp->m_stop;
246 	else {
247 		if (ISMOTION(vp))
248 			--vp->m_start.cno;
249 		vp->m_final = vp->m_stop;
250 	}
251 	return (0);
252 }
253 
254 /*
255  * v_zero -- 0
256  *	Move to the first column on this line.
257  *
258  * PUBLIC: int v_zero __P((SCR *, VICMD *));
259  */
260 int
261 v_zero(SCR *sp, VICMD *vp)
262 {
263 	/*
264 	 * !!!
265 	 * The 0 command succeeded if used as a command in the first column
266 	 * but failed if used as a motion component in the same situation.
267 	 */
268 	if (ISMOTION(vp) && vp->m_start.cno == 0) {
269 		v_sol(sp);
270 		return (1);
271 	}
272 
273 	/*
274 	 * All commands move to the end of the range.  Motion commands
275 	 * adjust the starting point to the character before the current
276 	 * one.
277 	 */
278 	vp->m_stop.cno = 0;
279 	if (ISMOTION(vp))
280 		--vp->m_start.cno;
281 	vp->m_final = vp->m_stop;
282 	return (0);
283 }
284