xref: /freebsd/contrib/nvi/common/cut.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
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
13 static const char sccsid[] = "$Id: cut.c,v 10.12 2012/02/11 15:52:33 zy Exp $";
14 #endif /* not lint */
15 
16 #include <sys/types.h>
17 #include <sys/queue.h>
18 
19 #include <bitstring.h>
20 #include <ctype.h>
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <limits.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 
28 #include "common.h"
29 
30 static void	cb_rotate(SCR *);
31 
32 /*
33  * cut --
34  *	Put a range of lines/columns into a TEXT buffer.
35  *
36  * There are two buffer areas, both found in the global structure.  The first
37  * is the linked list of all the buffers the user has named, the second is the
38  * unnamed buffer storage.  There is a pointer, too, which is the current
39  * default buffer, i.e. it may point to the unnamed buffer or a named buffer
40  * depending on into what buffer the last text was cut.  Logically, in both
41  * delete and yank operations, if the user names a buffer, the text is cut
42  * into it.  If it's a delete of information on more than a single line, the
43  * contents of the numbered buffers are rotated up one, the contents of the
44  * buffer named '9' are discarded, and the text is cut into the buffer named
45  * '1'.  The text is always cut into the unnamed buffer.
46  *
47  * In all cases, upper-case buffer names are the same as lower-case names,
48  * with the exception that they cause the buffer to be appended to instead
49  * of replaced.  Note, however, that if text is appended to a buffer, the
50  * default buffer only contains the appended text, not the entire contents
51  * of the buffer.
52  *
53  * !!!
54  * The contents of the default buffer would disappear after most operations
55  * in historic vi.  It's unclear that this is useful, so we don't bother.
56  *
57  * When users explicitly cut text into the numeric buffers, historic vi became
58  * genuinely strange.  I've never been able to figure out what was supposed to
59  * happen.  It behaved differently if you deleted text than if you yanked text,
60  * and, in the latter case, the text was appended to the buffer instead of
61  * replacing the contents.  Hopefully it's not worth getting right, and here
62  * we just treat the numeric buffers like any other named buffer.
63  *
64  * PUBLIC: int cut(SCR *, CHAR_T *, MARK *, MARK *, int);
65  */
66 int
67 cut(
68 	SCR *sp,
69 	CHAR_T *namep,
70 	MARK *fm,
71 	MARK *tm,
72 	int flags)
73 {
74 	CB *cbp;
75 	CHAR_T name = '\0';
76 	recno_t lno;
77 	int append, copy_one, copy_def;
78 
79 	/*
80 	 * If the user specified a buffer, put it there.  (This may require
81 	 * a copy into the numeric buffers.  We do the copy so that we don't
82 	 * have to reference count and so we don't have to deal with things
83 	 * like appends to buffers that are used multiple times.)
84 	 *
85 	 * Otherwise, if it's supposed to be put in a numeric buffer (usually
86 	 * a delete) put it there.  The rules for putting things in numeric
87 	 * buffers were historically a little strange.  There were three cases.
88 	 *
89 	 *	1: Some motions are always line mode motions, which means
90 	 *	   that the cut always goes into the numeric buffers.
91 	 *	2: Some motions aren't line mode motions, e.g. d10w, but
92 	 *	   can cross line boundaries.  For these commands, if the
93 	 *	   cut crosses a line boundary, it goes into the numeric
94 	 *	   buffers.  This includes most of the commands.
95 	 *	3: Some motions aren't line mode motions, e.g. d`<char>,
96 	 *	   but always go into the numeric buffers, regardless.  This
97 	 *	   was the commands: % ` / ? ( ) N n { } -- and nvi adds ^A.
98 	 *
99 	 * Otherwise, put it in the unnamed buffer.
100 	 */
101 	append = copy_one = copy_def = 0;
102 	if (namep != NULL) {
103 		name = *namep;
104 		if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
105 		    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
106 			copy_one = 1;
107 			cb_rotate(sp);
108 		}
109 		if ((append = isupper(name))) {
110 			if (!copy_one)
111 				copy_def = 1;
112 			name = tolower(name);
113 		}
114 namecb:		CBNAME(sp, cbp, name);
115 	} else if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
116 	    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
117 		name = '1';
118 		cb_rotate(sp);
119 		goto namecb;
120 	} else
121 		cbp = &sp->gp->dcb_store;
122 
123 copyloop:
124 	/*
125 	 * If this is a new buffer, create it and add it into the list.
126 	 * Otherwise, if it's not an append, free its current contents.
127 	 */
128 	if (cbp == NULL) {
129 		CALLOC_RET(sp, cbp, CB *, 1, sizeof(CB));
130 		cbp->name = name;
131 		TAILQ_INIT(cbp->textq);
132 		SLIST_INSERT_HEAD(sp->gp->cutq, cbp, q);
133 	} else if (!append) {
134 		text_lfree(cbp->textq);
135 		cbp->len = 0;
136 		cbp->flags = 0;
137 	}
138 
139 
140 	/* In line mode, it's pretty easy, just cut the lines. */
141 	if (LF_ISSET(CUT_LINEMODE)) {
142 		cbp->flags |= CB_LMODE;
143 		for (lno = fm->lno; lno <= tm->lno; ++lno)
144 			if (cut_line(sp, lno, 0, ENTIRE_LINE, cbp))
145 				goto cut_line_err;
146 	} else {
147 		/*
148 		 * Get the first line.  A length of ENTIRE_LINE causes
149 		 * cut_line to cut from the MARK to the end of the line.
150 		 */
151 		if (cut_line(sp, fm->lno, fm->cno, fm->lno != tm->lno ?
152 		    ENTIRE_LINE : (tm->cno - fm->cno) + 1, cbp))
153 			goto cut_line_err;
154 
155 		/* Get the intermediate lines. */
156 		for (lno = fm->lno; ++lno < tm->lno;)
157 			if (cut_line(sp, lno, 0, ENTIRE_LINE, cbp))
158 				goto cut_line_err;
159 
160 		/* Get the last line. */
161 		if (tm->lno != fm->lno &&
162 		    cut_line(sp, lno, 0, tm->cno + 1, cbp))
163 			goto cut_line_err;
164 	}
165 
166 	append = 0;		/* Only append to the named buffer. */
167 	sp->gp->dcbp = cbp;	/* Repoint the default buffer on each pass. */
168 
169 	if (copy_one) {		/* Copy into numeric buffer 1. */
170 		name = '1';
171 		CBNAME(sp, cbp, name);
172 		copy_one = 0;
173 		goto copyloop;
174 	}
175 	if (copy_def) {		/* Copy into the default buffer. */
176 		cbp = &sp->gp->dcb_store;
177 		copy_def = 0;
178 		goto copyloop;
179 	}
180 	return (0);
181 
182 cut_line_err:
183 	text_lfree(cbp->textq);
184 	cbp->len = 0;
185 	cbp->flags = 0;
186 	return (1);
187 }
188 
189 /*
190  * cb_rotate --
191  *	Rotate the numbered buffers up one.
192  */
193 static void
194 cb_rotate(SCR *sp)
195 {
196 	CB *cbp, *del_cbp = NULL, *pre_cbp = NULL;
197 
198 	SLIST_FOREACH(cbp, sp->gp->cutq, q) {
199 		switch(cbp->name) {
200 		case '1': case '2': case '3':
201 		case '4': case '5': case '6':
202 		case '7': case '8':
203 			cbp->name += 1;
204 			break;
205 		case '9':
206 			if (cbp == SLIST_FIRST(sp->gp->cutq))
207 				SLIST_REMOVE_HEAD(sp->gp->cutq, q);
208 			else
209 				SLIST_REMOVE_AFTER(pre_cbp, q);
210 			del_cbp = cbp;
211 			break;
212 		}
213 		pre_cbp = cbp;
214 	}
215 	if (del_cbp != NULL) {
216 		text_lfree(del_cbp->textq);
217 		free(del_cbp);
218 	}
219 }
220 
221 /*
222  * cut_line --
223  *	Cut a portion of a single line.
224  *
225  * PUBLIC: int cut_line(SCR *, recno_t, size_t, size_t, CB *);
226  */
227 int
228 cut_line(
229 	SCR *sp,
230 	recno_t lno,
231 	size_t fcno,
232 	size_t clen,
233 	CB *cbp)
234 {
235 	TEXT *tp;
236 	size_t len;
237 	CHAR_T *p;
238 
239 	/* Get the line. */
240 	if (db_get(sp, lno, DBG_FATAL, &p, &len))
241 		return (1);
242 
243 	/* Create a TEXT structure that can hold the entire line. */
244 	if ((tp = text_init(sp, NULL, 0, len)) == NULL)
245 		return (1);
246 
247 	/*
248 	 * If the line isn't empty and it's not the entire line,
249 	 * copy the portion we want, and reset the TEXT length.
250 	 */
251 	if (len != 0) {
252 		if (clen == ENTIRE_LINE)
253 			clen = len - fcno;
254 		MEMCPY(tp->lb, p + fcno, clen);
255 		tp->len = clen;
256 	}
257 
258 	/* Append to the end of the cut buffer. */
259 	TAILQ_INSERT_TAIL(cbp->textq, tp, q);
260 	cbp->len += tp->len;
261 
262 	return (0);
263 }
264 
265 /*
266  * cut_close --
267  *	Discard all cut buffers.
268  *
269  * PUBLIC: void cut_close(GS *);
270  */
271 void
272 cut_close(GS *gp)
273 {
274 	CB *cbp;
275 
276 	/* Free cut buffer list. */
277 	while ((cbp = SLIST_FIRST(gp->cutq)) != NULL) {
278 		if (!TAILQ_EMPTY(cbp->textq))
279 			text_lfree(cbp->textq);
280 		SLIST_REMOVE_HEAD(gp->cutq, q);
281 		free(cbp);
282 	}
283 
284 	/* Free default cut storage. */
285 	cbp = &gp->dcb_store;
286 	if (!TAILQ_EMPTY(cbp->textq))
287 		text_lfree(cbp->textq);
288 }
289 
290 /*
291  * text_init --
292  *	Allocate a new TEXT structure.
293  *
294  * PUBLIC: TEXT *text_init(SCR *, const CHAR_T *, size_t, size_t);
295  */
296 TEXT *
297 text_init(
298 	SCR *sp,
299 	const CHAR_T *p,
300 	size_t len,
301 	size_t total_len)
302 {
303 	TEXT *tp;
304 
305 	CALLOC(sp, tp, TEXT *, 1, sizeof(TEXT));
306 	if (tp == NULL)
307 		return (NULL);
308 	/* ANSI C doesn't define a call to malloc(3) for 0 bytes. */
309 	if ((tp->lb_len = total_len * sizeof(CHAR_T)) != 0) {
310 		MALLOC(sp, tp->lb, CHAR_T *, tp->lb_len);
311 		if (tp->lb == NULL) {
312 			free(tp);
313 			return (NULL);
314 		}
315 		if (p != NULL && len != 0)
316 			MEMCPY(tp->lb, p, len);
317 	}
318 	tp->len = len;
319 	return (tp);
320 }
321 
322 /*
323  * text_lfree --
324  *	Free a chain of text structures.
325  *
326  * PUBLIC: void text_lfree(TEXTH *);
327  */
328 void
329 text_lfree(TEXTH *headp)
330 {
331 	TEXT *tp;
332 
333 	while ((tp = TAILQ_FIRST(headp)) != NULL) {
334 		TAILQ_REMOVE(headp, tp, q);
335 		text_free(tp);
336 	}
337 }
338 
339 /*
340  * text_free --
341  *	Free a text structure.
342  *
343  * PUBLIC: void text_free(TEXT *);
344  */
345 void
346 text_free(TEXT *tp)
347 {
348 	if (tp->lb != NULL)
349 		free(tp->lb);
350 	free(tp);
351 }
352