2 * Copyright (c) 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 * Copyright (c) 1993, 1994, 1995, 1996
5 * Keith Bostic. All rights reserved.
7 * See the LICENSE file for redistribution information.
13 static const char sccsid[] = "$Id: vs_relative.c,v 10.19 2011/12/01 15:22:59 zy Exp $";
16 #include <sys/types.h>
17 #include <sys/queue.h>
20 #include <bitstring.h>
25 #include "../common/common.h"
30 * Return the logical column of the cursor in the line.
32 * PUBLIC: int vs_column(SCR *, size_t *);
35 vs_column(SCR *sp, size_t *colp)
41 *colp = (O_ISSET(sp, O_LEFTRIGHT) ?
42 vip->sc_smap->coff : (vip->sc_smap->soff - 1) * sp->cols) +
43 vip->sc_col - (O_ISSET(sp, O_NUMBER) ? O_NUMBER_LENGTH : 0);
49 * Return the screens necessary to display the line, or if specified,
50 * the physical character column within the line, including space
51 * required for the O_NUMBER and O_LIST options.
53 * PUBLIC: size_t vs_screens(SCR *, recno_t, size_t *);
56 vs_screens(SCR *sp, recno_t lno, size_t *cnop)
60 /* Left-right screens are simple, it's always 1. */
61 if (O_ISSET(sp, O_LEFTRIGHT))
65 * Check for a cached value. We maintain a cache because, if the
66 * line is large, this routine gets called repeatedly. One other
67 * hack, lots of time the cursor is on column one, which is an easy
71 if (VIP(sp)->ss_lno == lno)
72 return (VIP(sp)->ss_screens);
73 } else if (*cnop == 0)
76 /* Figure out how many columns the line/column needs. */
77 cols = vs_columns(sp, NULL, lno, cnop, NULL);
79 screens = (cols / sp->cols + (cols % sp->cols ? 1 : 0));
83 /* Cache the value. */
85 VIP(sp)->ss_lno = lno;
86 VIP(sp)->ss_screens = screens;
93 * Return the screen columns necessary to display the line, or,
94 * if specified, the physical character column within the line.
96 * PUBLIC: size_t vs_columns(SCR *, CHAR_T *, recno_t, size_t *, size_t *);
99 vs_columns(SCR *sp, CHAR_T *lp, recno_t lno, size_t *cnop, size_t *diffp)
101 size_t chlen, cno, curoff, last = 0, len, scno;
102 int ch, leftright, listset;
106 * Initialize the screen offset.
110 /* Leading number if O_NUMBER option set. */
111 if (O_ISSET(sp, O_NUMBER))
112 scno += O_NUMBER_LENGTH;
114 /* Need the line to go any further. */
116 (void)db_get(sp, lno, 0, &lp, &len);
121 /* Missing or empty lines are easy. */
123 done: if (diffp != NULL) /* XXX */
128 /* Store away the values of the list and leftright edit options. */
129 listset = O_ISSET(sp, O_LIST);
130 leftright = O_ISSET(sp, O_LEFTRIGHT);
133 * Initialize the pointer into the buffer and current offset.
138 /* Macro to return the display length of any signal character. */
139 #define CHLEN(val) (ch = *(UCHAR_T *)p++) == '\t' && \
140 !listset ? TAB_OFF(val) : KEY_COL(sp, ch);
143 * If folding screens (the historic vi screen format), past the end
144 * of the current screen, and the character was a tab, reset the
145 * current screen column to 0, and the total screen columns to the
146 * last column of the screen. Otherwise, display the rest of the
147 * character in the next screen.
149 #define TAB_RESET { \
151 if (!leftright && curoff >= sp->cols) \
154 scno -= scno % sp->cols; \
156 curoff -= sp->cols; \
160 chlen = CHLEN(curoff);
166 for (cno = *cnop;; --cno) {
167 chlen = CHLEN(curoff);
175 /* Add the trailing '$' if the O_LIST option set. */
176 if (listset && cnop == NULL)
177 scno += KEY_LEN(sp, '$');
180 * The text input screen code needs to know how much additional
181 * room the last two characters required, so that it can handle
182 * tab character displays correctly.
185 *diffp = scno - last;
191 * Return the physical column from the line that will display a
192 * character closest to the currently most attractive character
193 * position (which is stored as a screen column).
195 * PUBLIC: size_t vs_rcm(SCR *, recno_t, int);
198 vs_rcm(SCR *sp, recno_t lno, int islast)
202 /* Last character is easy, and common. */
204 if (db_get(sp, lno, 0, NULL, &len) || len == 0)
209 /* First character is easy, and common. */
213 return (vs_colpos(sp, lno, sp->rcm));
218 * Return the physical column from the line that will display a
219 * character closest to the specified screen column.
221 * PUBLIC: size_t vs_colpos(SCR *, recno_t, size_t);
224 vs_colpos(SCR *sp, recno_t lno, size_t cno)
226 size_t chlen, curoff, len, llen, off, scno;
227 int ch = 0, leftright, listset;
230 /* Need the line to go any further. */
231 (void)db_get(sp, lno, 0, &lp, &llen);
233 /* Missing or empty lines are easy. */
234 if (lp == NULL || llen == 0)
237 /* Store away the values of the list and leftright edit options. */
238 listset = O_ISSET(sp, O_LIST);
239 leftright = O_ISSET(sp, O_LEFTRIGHT);
241 /* Discard screen (logical) lines. */
242 off = cno / sp->cols;
244 for (scno = 0, p = lp, len = llen; off--;) {
245 for (; len && scno < sp->cols; --len)
249 * If reached the end of the physical line, return the last
250 * physical character in the line.
256 * If folding screens (the historic vi screen format), past
257 * the end of the current screen, and the character was a tab,
258 * reset the current screen column to 0. Otherwise, the rest
259 * of the character is displayed in the next screen.
261 if (leftright && ch == '\t')
267 /* Step through the line until reach the right character or EOL. */
268 for (curoff = scno; len--;) {
269 chlen = CHLEN(curoff);
272 * If we've reached the specific character, there are three
275 * 1: scno == cno, i.e. the current character ends at the
276 * screen character we care about.
277 * a: off < llen - 1, i.e. not the last character in
278 * the line, return the offset of the next character.
279 * b: else return the offset of the last character.
280 * 2: scno != cno, i.e. this character overruns the character
281 * we care about, return the offset of this character.
283 if ((scno += chlen) >= cno) {
285 return (scno == cno ?
286 (off < llen - 1 ? off : llen - 1) : off - 1);
292 /* No such character; return the start of the last character. */