xref: /openbsd/usr.bin/vi/common/cut.c (revision 898184e3)
1 /*	$OpenBSD: cut.c,v 1.11 2009/10/27 23:59:47 deraadt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1992, 1993, 1994, 1995, 1996
7  *	Keith Bostic.  All rights reserved.
8  *
9  * See the LICENSE file for redistribution information.
10  */
11 
12 #include "config.h"
13 
14 #include <sys/types.h>
15 #include <sys/queue.h>
16 
17 #include <bitstring.h>
18 #include <ctype.h>
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <limits.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 #include "common.h"
27 
28 static void	cb_rotate(SCR *);
29 
30 /*
31  * cut --
32  *	Put a range of lines/columns into a TEXT buffer.
33  *
34  * There are two buffer areas, both found in the global structure.  The first
35  * is the linked list of all the buffers the user has named, the second is the
36  * unnamed buffer storage.  There is a pointer, too, which is the current
37  * default buffer, i.e. it may point to the unnamed buffer or a named buffer
38  * depending on into what buffer the last text was cut.  Logically, in both
39  * delete and yank operations, if the user names a buffer, the text is cut
40  * into it.  If it's a delete of information on more than a single line, the
41  * contents of the numbered buffers are rotated up one, the contents of the
42  * buffer named '9' are discarded, and the text is cut into the buffer named
43  * '1'.  The text is always cut into the unnamed buffer.
44  *
45  * In all cases, upper-case buffer names are the same as lower-case names,
46  * with the exception that they cause the buffer to be appended to instead
47  * of replaced.  Note, however, that if text is appended to a buffer, the
48  * default buffer only contains the appended text, not the entire contents
49  * of the buffer.
50  *
51  * !!!
52  * The contents of the default buffer would disappear after most operations
53  * in historic vi.  It's unclear that this is useful, so we don't bother.
54  *
55  * When users explicitly cut text into the numeric buffers, historic vi became
56  * genuinely strange.  I've never been able to figure out what was supposed to
57  * happen.  It behaved differently if you deleted text than if you yanked text,
58  * and, in the latter case, the text was appended to the buffer instead of
59  * replacing the contents.  Hopefully it's not worth getting right, and here
60  * we just treat the numeric buffers like any other named buffer.
61  *
62  * PUBLIC: int cut(SCR *, CHAR_T *, MARK *, MARK *, int);
63  */
64 int
65 cut(sp, namep, fm, tm, flags)
66 	SCR *sp;
67 	CHAR_T *namep;
68 	MARK *fm, *tm;
69 	int flags;
70 {
71 	CB *cbp;
72 	CHAR_T name = '1';	/* default numeric buffer */
73 	recno_t lno;
74 	int append, copy_one, copy_def;
75 
76 	/*
77 	 * If the user specified a buffer, put it there.  (This may require
78 	 * a copy into the numeric buffers.  We do the copy so that we don't
79 	 * have to reference count and so we don't have to deal with things
80 	 * like appends to buffers that are used multiple times.)
81 	 *
82 	 * Otherwise, if it's supposed to be put in a numeric buffer (usually
83 	 * a delete) put it there.  The rules for putting things in numeric
84 	 * buffers were historically a little strange.  There were three cases.
85 	 *
86 	 *	1: Some motions are always line mode motions, which means
87 	 *	   that the cut always goes into the numeric buffers.
88 	 *	2: Some motions aren't line mode motions, e.g. d10w, but
89 	 *	   can cross line boundaries.  For these commands, if the
90 	 *	   cut crosses a line boundary, it goes into the numeric
91 	 *	   buffers.  This includes most of the commands.
92 	 *	3: Some motions aren't line mode motions, e.g. d`<char>,
93 	 *	   but always go into the numeric buffers, regardless.  This
94 	 *	   was the commands: % ` / ? ( ) N n { } -- and nvi adds ^A.
95 	 *
96 	 * Otherwise, put it in the unnamed buffer.
97 	 */
98 	append = copy_one = copy_def = 0;
99 	if (namep != NULL) {
100 		name = *namep;
101 		if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
102 		    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
103 			copy_one = 1;
104 			cb_rotate(sp);
105 		}
106 		if ((append = isupper(name)) == 1) {
107 			if (!copy_one)
108 				copy_def = 1;
109 			name = tolower(name);
110 		}
111 namecb:		CBNAME(sp, cbp, name);
112 	} else if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
113 	    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
114 		/* Copy into numeric buffer 1. */
115 		cb_rotate(sp);
116 		goto namecb;
117 	} else
118 		cbp = &sp->gp->dcb_store;
119 
120 copyloop:
121 	/*
122 	 * If this is a new buffer, create it and add it into the list.
123 	 * Otherwise, if it's not an append, free its current contents.
124 	 */
125 	if (cbp == NULL) {
126 		CALLOC_RET(sp, cbp, CB *, 1, sizeof(CB));
127 		cbp->name = name;
128 		CIRCLEQ_INIT(&cbp->textq);
129 		LIST_INSERT_HEAD(&sp->gp->cutq, cbp, q);
130 	} else if (!append) {
131 		text_lfree(&cbp->textq);
132 		cbp->len = 0;
133 		cbp->flags = 0;
134 	}
135 
136 
137 	/* In line mode, it's pretty easy, just cut the lines. */
138 	if (LF_ISSET(CUT_LINEMODE)) {
139 		cbp->flags |= CB_LMODE;
140 		for (lno = fm->lno; lno <= tm->lno; ++lno)
141 			if (cut_line(sp, lno, 0, CUT_LINE_TO_EOL, cbp))
142 				goto cut_line_err;
143 	} else {
144 		/*
145 		 * Get the first line.  A length of CUT_LINE_TO_EOL causes
146 		 * cut_line() to cut from the MARK to the end of the line.
147 		 */
148 		if (cut_line(sp, fm->lno, fm->cno, fm->lno != tm->lno ?
149 		    CUT_LINE_TO_EOL : (tm->cno - fm->cno) + 1, cbp))
150 			goto cut_line_err;
151 
152 		/* Get the intermediate lines. */
153 		for (lno = fm->lno; ++lno < tm->lno;)
154 			if (cut_line(sp, lno, 0, CUT_LINE_TO_EOL, cbp))
155 				goto cut_line_err;
156 
157 		/* Get the last line. */
158 		if (tm->lno != fm->lno &&
159 		    cut_line(sp, lno, 0, tm->cno + 1, cbp))
160 			goto cut_line_err;
161 	}
162 
163 	append = 0;		/* Only append to the named buffer. */
164 	sp->gp->dcbp = cbp;	/* Repoint the default buffer on each pass. */
165 
166 	if (copy_one) {		/* Copy into numeric buffer 1. */
167 		CBNAME(sp, cbp, name);
168 		copy_one = 0;
169 		goto copyloop;
170 	}
171 	if (copy_def) {		/* Copy into the default buffer. */
172 		cbp = &sp->gp->dcb_store;
173 		copy_def = 0;
174 		goto copyloop;
175 	}
176 	return (0);
177 
178 cut_line_err:
179 	text_lfree(&cbp->textq);
180 	cbp->len = 0;
181 	cbp->flags = 0;
182 	return (1);
183 }
184 
185 /*
186  * cb_rotate --
187  *	Rotate the numbered buffers up one.
188  */
189 static void
190 cb_rotate(sp)
191 	SCR *sp;
192 {
193 	CB *cbp, *del_cbp;
194 
195 	del_cbp = NULL;
196 	LIST_FOREACH(cbp, &sp->gp->cutq, q)
197 		switch(cbp->name) {
198 		case '1':
199 			cbp->name = '2';
200 			break;
201 		case '2':
202 			cbp->name = '3';
203 			break;
204 		case '3':
205 			cbp->name = '4';
206 			break;
207 		case '4':
208 			cbp->name = '5';
209 			break;
210 		case '5':
211 			cbp->name = '6';
212 			break;
213 		case '6':
214 			cbp->name = '7';
215 			break;
216 		case '7':
217 			cbp->name = '8';
218 			break;
219 		case '8':
220 			cbp->name = '9';
221 			break;
222 		case '9':
223 			del_cbp = cbp;
224 			break;
225 		}
226 	if (del_cbp != NULL) {
227 		LIST_REMOVE(del_cbp, q);
228 		text_lfree(&del_cbp->textq);
229 		free(del_cbp);
230 	}
231 }
232 
233 /*
234  * cut_line --
235  *	Cut a portion of a single line.
236  *
237  * PUBLIC: int cut_line(SCR *, recno_t, size_t, size_t, CB *);
238  */
239 int
240 cut_line(sp, lno, fcno, clen, cbp)
241 	SCR *sp;
242 	recno_t lno;
243 	size_t fcno, clen;
244 	CB *cbp;
245 {
246 	TEXT *tp;
247 	size_t len;
248 	char *p;
249 
250 	/* Get the line. */
251 	if (db_get(sp, lno, DBG_FATAL, &p, &len))
252 		return (1);
253 
254 	/* Create a TEXT structure that can hold the entire line. */
255 	if ((tp = text_init(sp, NULL, 0, len)) == NULL)
256 		return (1);
257 
258 	/*
259 	 * If the line isn't empty and it's not the entire line,
260 	 * copy the portion we want, and reset the TEXT length.
261 	 */
262 	if (len != 0) {
263 		if (clen == CUT_LINE_TO_EOL)
264 			clen = len - fcno;
265 		memcpy(tp->lb, p + fcno, clen);
266 		tp->len = clen;
267 	}
268 
269 	/* Append to the end of the cut buffer. */
270 	CIRCLEQ_INSERT_TAIL(&cbp->textq, tp, q);
271 	cbp->len += tp->len;
272 
273 	return (0);
274 }
275 
276 /*
277  * cut_close --
278  *	Discard all cut buffers.
279  *
280  * PUBLIC: void cut_close(GS *);
281  */
282 void
283 cut_close(gp)
284 	GS *gp;
285 {
286 	CB *cbp;
287 
288 	/* Free cut buffer list. */
289 	while ((cbp = LIST_FIRST(&gp->cutq)) != NULL) {
290 		if (CIRCLEQ_FIRST(&cbp->textq) != CIRCLEQ_END(&cbp->textq))
291 			text_lfree(&cbp->textq);
292 		LIST_REMOVE(cbp, q);
293 		free(cbp);
294 	}
295 
296 	/* Free default cut storage. */
297 	cbp = &gp->dcb_store;
298 	if (CIRCLEQ_FIRST(&cbp->textq) != CIRCLEQ_END(&cbp->textq))
299 		text_lfree(&cbp->textq);
300 }
301 
302 /*
303  * text_init --
304  *	Allocate a new TEXT structure.
305  *
306  * PUBLIC: TEXT *text_init(SCR *, const char *, size_t, size_t);
307  */
308 TEXT *
309 text_init(sp, p, len, total_len)
310 	SCR *sp;
311 	const char *p;
312 	size_t len, total_len;
313 {
314 	TEXT *tp;
315 
316 	CALLOC(sp, tp, TEXT *, 1, sizeof(TEXT));
317 	if (tp == NULL)
318 		return (NULL);
319 	/* ANSI C doesn't define a call to malloc(3) for 0 bytes. */
320 	if ((tp->lb_len = total_len) != 0) {
321 		MALLOC(sp, tp->lb, CHAR_T *, tp->lb_len);
322 		if (tp->lb == NULL) {
323 			free(tp);
324 			return (NULL);
325 		}
326 		if (p != NULL && len != 0)
327 			memcpy(tp->lb, p, len);
328 	}
329 	tp->len = len;
330 	return (tp);
331 }
332 
333 /*
334  * text_lfree --
335  *	Free a chain of text structures.
336  *
337  * PUBLIC: void text_lfree(TEXTH *);
338  */
339 void
340 text_lfree(headp)
341 	TEXTH *headp;
342 {
343 	TEXT *tp;
344 
345 	while ((tp = CIRCLEQ_FIRST(headp)) != CIRCLEQ_END(headp)) {
346 		CIRCLEQ_REMOVE(headp, tp, q);
347 		text_free(tp);
348 	}
349 }
350 
351 /*
352  * text_free --
353  *	Free a text structure.
354  *
355  * PUBLIC: void text_free(TEXT *);
356  */
357 void
358 text_free(tp)
359 	TEXT *tp;
360 {
361 	if (tp->lb != NULL)
362 		free(tp->lb);
363 	free(tp);
364 }
365