1 /* $NetBSD: vs_relative.c,v 1.3 2014/01/26 21:43:45 christos Exp $ */
2 /*-
3 * Copyright (c) 1993, 1994
4 * The Regents of the University of California. All rights reserved.
5 * Copyright (c) 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
16 static const char sccsid[] = "Id: vs_relative.c,v 10.18 2001/07/08 13:02:48 skimo Exp (Berkeley) Date: 2001/07/08 13:02:48 ";
17 #endif /* not lint */
18 #else
19 __RCSID("$NetBSD: vs_relative.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 * vs_column --
36 * Return the logical column of the cursor in the line.
37 *
38 * PUBLIC: int vs_column __P((SCR *, size_t *));
39 */
40 int
vs_column(SCR * sp,size_t * colp)41 vs_column(SCR *sp, size_t *colp)
42 {
43 VI_PRIVATE *vip;
44
45 vip = VIP(sp);
46
47 *colp = (O_ISSET(sp, O_LEFTRIGHT) ?
48 vip->sc_smap->coff : (vip->sc_smap->soff - 1) * sp->cols) +
49 vip->sc_col - (O_ISSET(sp, O_NUMBER) ? O_NUMBER_LENGTH : 0);
50 return (0);
51 }
52
53 /*
54 * vs_screens --
55 * Return the screens necessary to display the line, or if specified,
56 * the physical character column within the line, including space
57 * required for the O_NUMBER and O_LIST options.
58 *
59 * PUBLIC: size_t vs_screens __P((SCR *, db_recno_t, size_t *));
60 */
61 size_t
vs_screens(SCR * sp,db_recno_t lno,size_t * cnop)62 vs_screens(SCR *sp, db_recno_t lno, size_t *cnop)
63 {
64 size_t cols, screens;
65
66 /* Left-right screens are simple, it's always 1. */
67 if (O_ISSET(sp, O_LEFTRIGHT))
68 return (1);
69
70 /*
71 * Check for a cached value. We maintain a cache because, if the
72 * line is large, this routine gets called repeatedly. One other
73 * hack, lots of time the cursor is on column one, which is an easy
74 * one.
75 */
76 if (cnop == NULL) {
77 if (VIP(sp)->ss_lno == lno)
78 return (VIP(sp)->ss_screens);
79 } else if (*cnop == 0)
80 return (1);
81
82 /* Figure out how many columns the line/column needs. */
83 cols = vs_columns(sp, NULL, lno, cnop, NULL);
84
85 screens = (cols / sp->cols + (cols % sp->cols ? 1 : 0));
86 if (screens == 0)
87 screens = 1;
88
89 /* Cache the value. */
90 if (cnop == NULL) {
91 VIP(sp)->ss_lno = lno;
92 VIP(sp)->ss_screens = screens;
93 }
94 return (screens);
95 }
96
97 /*
98 * vs_columns --
99 * Return the screen columns necessary to display the line, or,
100 * if specified, the physical character column within the line.
101 *
102 * PUBLIC: size_t vs_columns __P((SCR *, CHAR_T *, db_recno_t, size_t *, size_t *));
103 */
104 size_t
vs_columns(SCR * sp,CHAR_T * lp,db_recno_t lno,size_t * cnop,size_t * diffp)105 vs_columns(SCR *sp, CHAR_T *lp, db_recno_t lno, size_t *cnop, size_t *diffp)
106 {
107 size_t chlen, cno, curoff, last = 0, len, scno;
108 int ch, leftright, listset;
109 CHAR_T *p;
110
111 /*
112 * Initialize the screen offset.
113 */
114 scno = 0;
115
116 /* Leading number if O_NUMBER option set. */
117 if (O_ISSET(sp, O_NUMBER))
118 scno += O_NUMBER_LENGTH;
119
120 /* Need the line to go any further. */
121 if (lp == NULL) {
122 (void)db_get(sp, lno, 0, &lp, &len);
123 if (len == 0)
124 goto done;
125 }
126
127 /* Missing or empty lines are easy. */
128 if (lp == NULL) {
129 done: if (diffp != NULL) /* XXX */
130 *diffp = 0;
131 return scno;
132 }
133
134 /* Store away the values of the list and leftright edit options. */
135 listset = O_ISSET(sp, O_LIST);
136 leftright = O_ISSET(sp, O_LEFTRIGHT);
137
138 /*
139 * Initialize the pointer into the buffer and current offset.
140 */
141 p = lp;
142 curoff = 0;
143
144 /* Macro to return the display length of any signal character. */
145 #define CHLEN(val) (ch = *(UCHAR_T *)p++) == '\t' && \
146 !listset ? TAB_OFF(val) : KEY_COL(sp, ch);
147
148 /*
149 * If folding screens (the historic vi screen format), past the end
150 * of the current screen, and the character was a tab, reset the
151 * current screen column to 0, and the total screen columns to the
152 * last column of the screen. Otherwise, display the rest of the
153 * character in the next screen.
154 */
155 #define TAB_RESET { \
156 curoff += chlen; \
157 if (!leftright && curoff >= sp->cols) { \
158 if (ch == '\t') { \
159 curoff = 0; \
160 scno -= scno % sp->cols; \
161 } else \
162 curoff -= sp->cols; \
163 } \
164 }
165 if (cnop == NULL)
166 while (len--) {
167 chlen = CHLEN(curoff);
168 last = scno;
169 scno += chlen;
170 TAB_RESET;
171 }
172 else
173 for (cno = *cnop;; --cno) {
174 chlen = CHLEN(curoff);
175 last = scno;
176 scno += chlen;
177 TAB_RESET;
178 if (cno == 0)
179 break;
180 }
181
182 /* Add the trailing '$' if the O_LIST option set. */
183 if (listset && cnop == NULL)
184 scno += KEY_LEN(sp, '$');
185
186 /*
187 * The text input screen code needs to know how much additional
188 * room the last two characters required, so that it can handle
189 * tab character displays correctly.
190 */
191 if (diffp != NULL)
192 *diffp = scno - last;
193 return (scno);
194 }
195
196 /*
197 * vs_rcm --
198 * Return the physical column from the line that will display a
199 * character closest to the currently most attractive character
200 * position (which is stored as a screen column).
201 *
202 * PUBLIC: size_t vs_rcm __P((SCR *, db_recno_t, int));
203 */
204 size_t
vs_rcm(SCR * sp,db_recno_t lno,int islast)205 vs_rcm(SCR *sp, db_recno_t lno, int islast)
206 {
207 size_t len;
208
209 /* Last character is easy, and common. */
210 if (islast) {
211 if (db_get(sp, lno, 0, NULL, &len) || len == 0)
212 return (0);
213 return (len - 1);
214 }
215
216 /* First character is easy, and common. */
217 if (sp->rcm == 0)
218 return (0);
219
220 return (vs_colpos(sp, lno, sp->rcm));
221 }
222
223 /*
224 * vs_colpos --
225 * Return the physical column from the line that will display a
226 * character closest to the specified screen column.
227 *
228 * PUBLIC: size_t vs_colpos __P((SCR *, db_recno_t, size_t));
229 */
230 size_t
vs_colpos(SCR * sp,db_recno_t lno,size_t cno)231 vs_colpos(SCR *sp, db_recno_t lno, size_t cno)
232 {
233 size_t chlen, curoff, len, llen, off, scno;
234 int ch = 0, leftright, listset;
235 CHAR_T *lp, *p;
236
237 /* Need the line to go any further. */
238 (void)db_get(sp, lno, 0, &lp, &llen);
239
240 /* Missing or empty lines are easy. */
241 if (lp == NULL || llen == 0)
242 return (0);
243
244 /* Store away the values of the list and leftright edit options. */
245 listset = O_ISSET(sp, O_LIST);
246 leftright = O_ISSET(sp, O_LEFTRIGHT);
247
248 /* Discard screen (logical) lines. */
249 off = cno / sp->cols;
250 cno %= sp->cols;
251 for (scno = 0, p = lp, len = llen; off--;) {
252 for (; len && scno < sp->cols; --len)
253 scno += CHLEN(scno);
254
255 /*
256 * If reached the end of the physical line, return the last
257 * physical character in the line.
258 */
259 if (len == 0)
260 return (llen - 1);
261
262 /*
263 * If folding screens (the historic vi screen format), past
264 * the end of the current screen, and the character was a tab,
265 * reset the current screen column to 0. Otherwise, the rest
266 * of the character is displayed in the next screen.
267 */
268 if (leftright && ch == '\t')
269 scno = 0;
270 else
271 scno -= sp->cols;
272 }
273
274 /* Step through the line until reach the right character or EOL. */
275 for (curoff = scno; len--;) {
276 chlen = CHLEN(curoff);
277
278 /*
279 * If we've reached the specific character, there are three
280 * cases.
281 *
282 * 1: scno == cno, i.e. the current character ends at the
283 * screen character we care about.
284 * a: off < llen - 1, i.e. not the last character in
285 * the line, return the offset of the next character.
286 * b: else return the offset of the last character.
287 * 2: scno != cno, i.e. this character overruns the character
288 * we care about, return the offset of this character.
289 */
290 if ((scno += chlen) >= cno) {
291 off = p - lp;
292 return (scno == cno ?
293 (off < llen - 1 ? off : llen - 1) : off - 1);
294 }
295
296 TAB_RESET;
297 }
298
299 /* No such character; return the start of the last character. */
300 return (llen - 1);
301 }
302