v_left.c revision 19304 
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
13static const char sccsid[] = "@(#)v_left.c	10.7 (Berkeley) 3/6/96";
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 */
33int
34v_left(sp, vp)
35	SCR *sp;
36	VICMD *vp;
37{
38	recno_t cnt;
39
40	/*
41	 * !!!
42	 * The ^H and h commands always failed in the first column.
43	 */
44	if (vp->m_start.cno == 0) {
45		v_sol(sp);
46		return (1);
47	}
48
49	/* Find the end of the range. */
50	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
51	if (vp->m_start.cno > cnt)
52		vp->m_stop.cno = vp->m_start.cno - cnt;
53	else
54		vp->m_stop.cno = 0;
55
56	/*
57	 * All commands move to the end of the range.  Motion commands
58	 * adjust the starting point to the character before the current
59	 * one.
60	 */
61	if (ISMOTION(vp))
62		--vp->m_start.cno;
63	vp->m_final = vp->m_stop;
64	return (0);
65}
66
67/*
68 * v_cfirst -- [count]_
69 *	Move to the first non-blank character in a line.
70 *
71 * PUBLIC: int v_cfirst __P((SCR *, VICMD *));
72 */
73int
74v_cfirst(sp, vp)
75	SCR *sp;
76	VICMD *vp;
77{
78	recno_t cnt, lno;
79
80	/*
81	 * !!!
82	 * If the _ is a motion component, it makes the command a line motion
83	 * e.g. "d_" deletes the line.  It also means that the cursor doesn't
84	 * move.
85	 *
86	 * The _ command never failed in the first column.
87	 */
88	if (ISMOTION(vp))
89		F_SET(vp, VM_LMODE);
90	/*
91	 * !!!
92	 * Historically a specified count makes _ move down count - 1
93	 * rows, so, "3_" is the same as "2j_".
94	 */
95	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
96	if (cnt != 1) {
97		--vp->count;
98		return (v_down(sp, vp));
99	}
100
101	/*
102	 * Move to the first non-blank.
103	 *
104	 * Can't just use RCM_SET_FNB, in case _ is used as the motion
105	 * component of another command.
106	 */
107	vp->m_stop.cno = 0;
108	if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
109		return (1);
110
111	/*
112	 * !!!
113	 * The _ command has to fail if the file is empty and we're doing
114	 * a delete.  If deleting line 1, and 0 is the first nonblank,
115	 * make the check.
116	 */
117	if (vp->m_stop.lno == 1 &&
118	    vp->m_stop.cno == 0 && ISCMD(vp->rkp, 'd')) {
119		if (db_last(sp, &lno))
120			return (1);
121		if (lno == 0) {
122			v_sol(sp);
123			return (1);
124		}
125	}
126
127	/*
128	 * Delete and non-motion commands move to the end of the range,
129	 * yank stays at the start.  Ignore others.
130	 */
131	vp->m_final =
132	    ISMOTION(vp) && ISCMD(vp->rkp, 'y') ? vp->m_start : vp->m_stop;
133	return (0);
134}
135
136/*
137 * v_first -- ^
138 *	Move to the first non-blank character in this line.
139 *
140 * PUBLIC: int v_first __P((SCR *, VICMD *));
141 */
142int
143v_first(sp, vp)
144	SCR *sp;
145	VICMD *vp;
146{
147	/*
148	 * !!!
149	 * Yielding to none in our quest for compatibility with every
150	 * historical blemish of vi, no matter how strange it might be,
151	 * we permit the user to enter a count and then ignore it.
152	 */
153
154	/*
155	 * Move to the first non-blank.
156	 *
157	 * Can't just use RCM_SET_FNB, in case ^ is used as the motion
158	 * component of another command.
159	 */
160	vp->m_stop.cno = 0;
161	if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
162		return (1);
163
164	/*
165	 * !!!
166	 * The ^ command succeeded if used as a command when the cursor was
167	 * on the first non-blank in the line, but failed if used as a motion
168	 * component in the same situation.
169	 */
170	if (ISMOTION(vp) && vp->m_start.cno == vp->m_stop.cno) {
171		v_sol(sp);
172		return (1);
173	}
174
175	/*
176	 * If moving right, non-motion commands move to the end of the range.
177	 * Delete and yank stay at the start.  Motion commands adjust the
178	 * ending point to the character before the current ending charcter.
179	 *
180	 * If moving left, all commands move to the end of the range.  Motion
181	 * commands adjust the starting point to the character before the
182	 * current starting character.
183	 */
184	if (vp->m_start.cno < vp->m_stop.cno)
185		if (ISMOTION(vp)) {
186			--vp->m_stop.cno;
187			vp->m_final = vp->m_start;
188		} else
189			vp->m_final = vp->m_stop;
190	else {
191		if (ISMOTION(vp))
192			--vp->m_start.cno;
193		vp->m_final = vp->m_stop;
194	}
195	return (0);
196}
197
198/*
199 * v_ncol -- [count]|
200 *	Move to column count or the first column on this line.  If the
201 *	requested column is past EOL, move to EOL.  The nasty part is
202 *	that we have to know character column widths to make this work.
203 *
204 * PUBLIC: int v_ncol __P((SCR *, VICMD *));
205 */
206int
207v_ncol(sp, vp)
208	SCR *sp;
209	VICMD *vp;
210{
211	if (F_ISSET(vp, VC_C1SET) && vp->count > 1) {
212		--vp->count;
213		vp->m_stop.cno =
214		    vs_colpos(sp, vp->m_start.lno, (size_t)vp->count);
215		/*
216		 * !!!
217		 * The | command succeeded if used as a command and the cursor
218		 * didn't move, but failed if used as a motion component in the
219		 * same situation.
220		 */
221		if (ISMOTION(vp) && vp->m_stop.cno == vp->m_start.cno) {
222			v_nomove(sp);
223			return (1);
224		}
225	} else {
226		/*
227		 * !!!
228		 * The | command succeeded if used as a command in column 0
229		 * without a count, but failed if used as a motion component
230		 * in the same situation.
231		 */
232		if (ISMOTION(vp) && vp->m_start.cno == 0) {
233			v_sol(sp);
234			return (1);
235		}
236		vp->m_stop.cno = 0;
237	}
238
239	/*
240	 * If moving right, non-motion commands move to the end of the range.
241	 * Delete and yank stay at the start.  Motion commands adjust the
242	 * ending point to the character before the current ending charcter.
243	 *
244	 * If moving left, all commands move to the end of the range.  Motion
245	 * commands adjust the starting point to the character before the
246	 * current starting character.
247	 */
248	if (vp->m_start.cno < vp->m_stop.cno)
249		if (ISMOTION(vp)) {
250			--vp->m_stop.cno;
251			vp->m_final = vp->m_start;
252		} else
253			vp->m_final = vp->m_stop;
254	else {
255		if (ISMOTION(vp))
256			--vp->m_start.cno;
257		vp->m_final = vp->m_stop;
258	}
259	return (0);
260}
261
262/*
263 * v_zero -- 0
264 *	Move to the first column on this line.
265 *
266 * PUBLIC: int v_zero __P((SCR *, VICMD *));
267 */
268int
269v_zero(sp, vp)
270	SCR *sp;
271	VICMD *vp;
272{
273	/*
274	 * !!!
275	 * The 0 command succeeded if used as a command in the first column
276	 * but failed if used as a motion component in the same situation.
277	 */
278	if (ISMOTION(vp) && vp->m_start.cno == 0) {
279		v_sol(sp);
280		return (1);
281	}
282
283	/*
284	 * All commands move to the end of the range.  Motion commands
285	 * adjust the starting point to the character before the current
286	 * one.
287	 */
288	vp->m_stop.cno = 0;
289	if (ISMOTION(vp))
290		--vp->m_start.cno;
291	vp->m_final = vp->m_stop;
292	return (0);
293}
294