xref: /illumos-gate/usr/src/lib/libcurses/screen/mbaddch.c (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*  Copyright (c) 1988 AT&T */
23 /*    All Rights Reserved   */
24 
25 
26 /*
27  *      Copyright (c) 1997, by Sun Microsystems, Inc.
28  *      All rights reserved.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 /*LINTLIBRARY*/
34 
35 #include	<sys/types.h>
36 #include	"curses_inc.h"
37 
38 /*
39  *	Clear the space occupied by a multicolumn character
40  */
41 
42 int
43 _mbclrch(WINDOW *win, int y, int x)
44 {
45 	chtype	*wcp, *ep, *wp, wc;
46 
47 	/* ASSERT(_scrmax > 1); */
48 
49 	wcp = win->_y[y];
50 	wp = wcp + x;
51 
52 	/* compute the bounds for the character */
53 	if (ISCBIT(*wp)) {
54 		for (; wp >= wcp; --wp)
55 			if (!ISCBIT(*wp))
56 				break;
57 		if (wp < wcp)
58 			return (ERR);
59 	}
60 	wc = RBYTE(*wp);
61 	ep = wp + _curs_scrwidth[TYPE(wc)];
62 	if (ep > wcp + win->_maxx)
63 		return (ERR);
64 
65 	/* update the change structure */
66 	/*LINTED*/
67 	if ((x = (int)(wp - wcp)) < win->_firstch[y])
68 		/*LINTED*/
69 		win->_firstch[y] = (short)x;
70 	/*LINTED*/
71 	if ((x = (int)(ep - wcp) - 1) > win->_lastch[y])
72 		/*LINTED*/
73 		win->_lastch[y] = (short)x;
74 
75 	/* clear the character */
76 	for (; wp < ep; ++wp)
77 		*wp = win->_bkgd;
78 	return (OK);
79 }
80 
81 
82 
83 /*
84  *	Make sure the window cursor point to a valid place.
85  *	If win->_insmode or isedge, the cursor has to
86  *	point to the start of a whole character; otherwise, the
87  *	cursor has to point to a part of a whole character.
88  */
89 
90 int
91 _mbvalid(WINDOW *win)
92 {
93 	chtype	*wp, *wcp, *ecp, wc;
94 	int		x;
95 	bool	isedge;
96 
97 	/* ASSERT(_scrmax > 1); */
98 
99 	x = win->_curx;
100 	wcp = win->_y[win->_cury];
101 	wp = wcp + x;
102 	if (!ISMBIT(*wp))
103 		return (OK);
104 
105 	ecp = wcp + win->_maxx;
106 	isedge = FALSE;
107 
108 	/* make wp points to the start column of a mb-character */
109 	if (ISCBIT(*wp)) {
110 		for (; wp >= wcp; --wp)
111 			if (!ISCBIT(*wp))
112 				break;
113 		if (wp < wcp) {
114 			for (wp = wcp + x + 1; wp < ecp; ++wp)
115 				if (!ISCBIT(*wp))
116 					break;
117 			if (wp >= ecp)
118 				return (ERR);
119 			isedge = TRUE;
120 		}
121 	}
122 
123 	/* make sure that wp points to a whole character */
124 	wc = RBYTE(*wp);
125 	if (wp + _curs_scrwidth[TYPE(wc)] > ecp) {
126 		for (wp -= 1; wp >= wcp; --wp)
127 			if (!ISCBIT(*wp))
128 				break;
129 		if (wp < wcp)
130 			return (ERR);
131 		isedge = TRUE;
132 	}
133 
134 	if (isedge || win->_insmode)
135 		/*LINTED*/
136 		win->_curx = (short)(wp-wcp);
137 	return (OK);
138 }
139 
140 
141 
142 /*
143  *	Add/insert multi-byte characters
144  */
145 
146 int
147 _mbaddch(WINDOW *win, chtype a, chtype c)
148 {
149 	int		n, x, y, nc, m, len, nbyte, ty;
150 	chtype		*wcp, wc;
151 	char		*wch, rc[2];
152 
153 	/* ASSERT(_mbtrue); */
154 
155 	/* decode the character into a sequence of bytes */
156 	nc = 0;
157 	if (ISCBIT(c))
158 		/*LINTED*/
159 		rc[nc++] = (char)(LBYTE(c)|MBIT);
160 	if (ISMBIT(c))
161 		/*LINTED*/
162 		rc[nc++] = (char)RBYTE(c);
163 
164 	a |= win->_attrs;
165 
166 	/* add the sequence to the image */
167 	for (n = 0; n < nc; ++n) {
168 		wc = RBYTE(rc[n]);
169 		ty = TYPE(wc);
170 		wch = win->_waitc;
171 
172 		/* first byte of a multi-byte character */
173 		if (ty > 0 || win->_nbyte < 0) {
174 			/*LINTED*/
175 			wch[0] = (char)wc;
176 			win->_nbyte = cswidth[ty] + (ty == 0 ? 0 : 1);
177 			win->_index = 1;
178 		} else {
179 		/* non-first byte */
180 			/*LINTED*/
181 			wch[win->_index] = (char)wc;
182 			win->_index += 1;
183 		}
184 
185 		/* if character is not ready to process */
186 		if (win->_index < win->_nbyte)
187 			continue;
188 
189 		/* begin processing the character */
190 		nbyte = win->_nbyte;
191 		win->_nbyte = -1;
192 		wc = RBYTE(wch[0]);
193 		len = _curs_scrwidth[TYPE(wc)];
194 
195 		/* window too small or char cannot be stored */
196 		if (len > win->_maxx || 2*len < nbyte)
197 			continue;
198 
199 		/* if the character won't fit into the line */
200 		if ((win->_curx + len) > win->_maxx &&
201 		    (win->_insmode || waddch(win, '\n') == ERR))
202 			continue;
203 
204 		y = win->_cury;
205 		x = win->_curx;
206 		wcp = win->_y[y] + x;
207 
208 		if (win->_insmode) {
209 			/* perform the right shift */
210 			if (_mbinsshift(win, len) == ERR)
211 				continue;
212 		} else if (_scrmax > 1) {
213 			/* clear any multi-byte char about to be overwritten */
214 			for (m = 0; m < len; ++m)
215 				if (ISMBIT(wcp[m]) &&
216 				    _mbclrch(win, y, x + m) == ERR)
217 					break;
218 			if (m < len)
219 				continue;
220 		}
221 
222 		/* pack two bytes at a time */
223 		for (m = nbyte/2; m > 0; m -= 1, wch += 2)
224 			*wcp++ = _CHAR((RBYTE(wch[1]) << 8) |
225 			    RBYTE(wch[0])) | CBIT | a;
226 
227 		/* do the remaining byte if any */
228 		if ((nbyte%2) != 0)
229 			*wcp++ = RBYTE(wch[0]) | CBIT | a;
230 
231 		/* fill-in for remaining display columns */
232 		for (m = (nbyte / 2) + (nbyte % 2); m < len; ++m)
233 			*wcp++ = (CBIT|MBIT) | a;
234 
235 		/* the first column has Continue BIT off */
236 		win->_y[y][x] &= ~CBIT;
237 
238 		if (win->_insmode == FALSE) {
239 			if (x < win->_firstch[y])
240 				/*LINTED*/
241 				win->_firstch[y] = (short)x;
242 			if ((x += len-1) >= win->_maxx)
243 				x = win->_maxx-1;
244 			if (x > win->_lastch[y])
245 				/*LINTED*/
246 				win->_lastch[y] = (short)x;
247 
248 			if ((win->_curx += len) >= win->_maxx) {
249 				if (y >= (win->_maxy-1) || y == win->_bmarg) {
250 					win->_curx = win->_maxx-1;
251 					if (wscrl(win, 1) == ERR)
252 						continue;
253 				} else {
254 					win->_cury += 1;
255 					win->_curx = 0;
256 				}
257 			}
258 		}
259 	}
260 
261 	return (OK);
262 }
263