xref: /freebsd/contrib/nvi/common/cut.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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 #include <sys/types.h>
13 #include <sys/queue.h>
14 #include <sys/time.h>
15 
16 #include <bitstring.h>
17 #include <ctype.h>
18 #include <errno.h>
19 #include <fcntl.h>
20 #include <limits.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 
25 #include "common.h"
26 
27 static void	cb_rotate(SCR *);
28 
29 /*
30  * cut --
31  *	Put a range of lines/columns into a TEXT buffer.
32  *
33  * There are two buffer areas, both found in the global structure.  The first
34  * is the linked list of all the buffers the user has named, the second is the
35  * unnamed buffer storage.  There is a pointer, too, which is the current
36  * default buffer, i.e. it may point to the unnamed buffer or a named buffer
37  * depending on into what buffer the last text was cut.  Logically, in both
38  * delete and yank operations, if the user names a buffer, the text is cut
39  * into it.  If it's a delete of information on more than a single line, the
40  * contents of the numbered buffers are rotated up one, the contents of the
41  * buffer named '9' are discarded, and the text is cut into the buffer named
42  * '1'.  The text is always cut into the unnamed buffer.
43  *
44  * In all cases, upper-case buffer names are the same as lower-case names,
45  * with the exception that they cause the buffer to be appended to instead
46  * of replaced.  Note, however, that if text is appended to a buffer, the
47  * default buffer only contains the appended text, not the entire contents
48  * of the buffer.
49  *
50  * !!!
51  * The contents of the default buffer would disappear after most operations
52  * in historic vi.  It's unclear that this is useful, so we don't bother.
53  *
54  * When users explicitly cut text into the numeric buffers, historic vi became
55  * genuinely strange.  I've never been able to figure out what was supposed to
56  * happen.  It behaved differently if you deleted text than if you yanked text,
57  * and, in the latter case, the text was appended to the buffer instead of
58  * replacing the contents.  Hopefully it's not worth getting right, and here
59  * we just treat the numeric buffers like any other named buffer.
60  *
61  * PUBLIC: int cut(SCR *, CHAR_T *, MARK *, MARK *, int);
62  */
63 int
64 cut(SCR *sp, CHAR_T *namep, MARK *fm, MARK *tm, int flags)
65 {
66 	CB *cbp;
67 	CHAR_T name = '\0';
68 	recno_t lno;
69 	int append, copy_one, copy_def;
70 
71 	/*
72 	 * If the user specified a buffer, put it there.  (This may require
73 	 * a copy into the numeric buffers.  We do the copy so that we don't
74 	 * have to reference count and so we don't have to deal with things
75 	 * like appends to buffers that are used multiple times.)
76 	 *
77 	 * Otherwise, if it's supposed to be put in a numeric buffer (usually
78 	 * a delete) put it there.  The rules for putting things in numeric
79 	 * buffers were historically a little strange.  There were three cases.
80 	 *
81 	 *	1: Some motions are always line mode motions, which means
82 	 *	   that the cut always goes into the numeric buffers.
83 	 *	2: Some motions aren't line mode motions, e.g. d10w, but
84 	 *	   can cross line boundaries.  For these commands, if the
85 	 *	   cut crosses a line boundary, it goes into the numeric
86 	 *	   buffers.  This includes most of the commands.
87 	 *	3: Some motions aren't line mode motions, e.g. d`<char>,
88 	 *	   but always go into the numeric buffers, regardless.  This
89 	 *	   was the commands: % ` / ? ( ) N n { } -- and nvi adds ^A.
90 	 *
91 	 * Otherwise, put it in the unnamed buffer.
92 	 */
93 	append = copy_one = copy_def = 0;
94 	if (namep != NULL) {
95 		name = *namep;
96 		if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
97 		    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
98 			copy_one = 1;
99 			cb_rotate(sp);
100 		}
101 		if ((append = isupper(name))) {
102 			if (!copy_one)
103 				copy_def = 1;
104 			name = tolower(name);
105 		}
106 namecb:		CBNAME(sp, cbp, name);
107 	} else if (LF_ISSET(CUT_NUMREQ) || (LF_ISSET(CUT_NUMOPT) &&
108 	    (LF_ISSET(CUT_LINEMODE) || fm->lno != tm->lno))) {
109 		name = '1';
110 		cb_rotate(sp);
111 		goto namecb;
112 	} else
113 		cbp = &sp->gp->dcb_store;
114 
115 copyloop:
116 	/*
117 	 * If this is a new buffer, create it and add it into the list.
118 	 * Otherwise, if it's not an append, free its current contents.
119 	 */
120 	if (cbp == NULL) {
121 		CALLOC_RET(sp, cbp, 1, sizeof(CB));
122 		cbp->name = name;
123 		TAILQ_INIT(cbp->textq);
124 		SLIST_INSERT_HEAD(sp->gp->cutq, cbp, q);
125 	} else if (!append) {
126 		text_lfree(cbp->textq);
127 		cbp->len = 0;
128 		cbp->flags = 0;
129 	}
130 
131 
132 	/* In line mode, it's pretty easy, just cut the lines. */
133 	if (LF_ISSET(CUT_LINEMODE)) {
134 		cbp->flags |= CB_LMODE;
135 		for (lno = fm->lno; lno <= tm->lno; ++lno)
136 			if (cut_line(sp, lno, 0, ENTIRE_LINE, cbp))
137 				goto cut_line_err;
138 	} else {
139 		/*
140 		 * Get the first line.  A length of ENTIRE_LINE causes
141 		 * cut_line to cut from the MARK to the end of the line.
142 		 */
143 		if (cut_line(sp, fm->lno, fm->cno, fm->lno != tm->lno ?
144 		    ENTIRE_LINE : (tm->cno - fm->cno) + 1, cbp))
145 			goto cut_line_err;
146 
147 		/* Get the intermediate lines. */
148 		for (lno = fm->lno; ++lno < tm->lno;)
149 			if (cut_line(sp, lno, 0, ENTIRE_LINE, cbp))
150 				goto cut_line_err;
151 
152 		/* Get the last line. */
153 		if (tm->lno != fm->lno &&
154 		    cut_line(sp, lno, 0, tm->cno + 1, cbp))
155 			goto cut_line_err;
156 	}
157 
158 	append = 0;		/* Only append to the named buffer. */
159 	sp->gp->dcbp = cbp;	/* Repoint the default buffer on each pass. */
160 
161 	if (copy_one) {		/* Copy into numeric buffer 1. */
162 		name = '1';
163 		CBNAME(sp, cbp, name);
164 		copy_one = 0;
165 		goto copyloop;
166 	}
167 	if (copy_def) {		/* Copy into the default buffer. */
168 		cbp = &sp->gp->dcb_store;
169 		copy_def = 0;
170 		goto copyloop;
171 	}
172 	return (0);
173 
174 cut_line_err:
175 	text_lfree(cbp->textq);
176 	cbp->len = 0;
177 	cbp->flags = 0;
178 	return (1);
179 }
180 
181 /*
182  * cb_rotate --
183  *	Rotate the numbered buffers up one.
184  */
185 static void
186 cb_rotate(SCR *sp)
187 {
188 	CB *cbp, *del_cbp = NULL, *pre_cbp = NULL;
189 
190 	SLIST_FOREACH(cbp, sp->gp->cutq, q) {
191 		switch(cbp->name) {
192 		case '1': case '2': case '3':
193 		case '4': case '5': case '6':
194 		case '7': case '8':
195 			cbp->name += 1;
196 			break;
197 		case '9':
198 			if (cbp == SLIST_FIRST(sp->gp->cutq))
199 				SLIST_REMOVE_HEAD(sp->gp->cutq, q);
200 			else
201 				SLIST_REMOVE_AFTER(pre_cbp, q);
202 			del_cbp = cbp;
203 			break;
204 		}
205 		pre_cbp = cbp;
206 	}
207 	if (del_cbp != NULL) {
208 		text_lfree(del_cbp->textq);
209 		free(del_cbp);
210 	}
211 }
212 
213 /*
214  * cut_line --
215  *	Cut a portion of a single line.
216  *
217  * PUBLIC: int cut_line(SCR *, recno_t, size_t, size_t, CB *);
218  */
219 int
220 cut_line(SCR *sp, recno_t lno, size_t fcno, size_t clen, CB *cbp)
221 {
222 	TEXT *tp;
223 	size_t len;
224 	CHAR_T *p;
225 
226 	/* Get the line. */
227 	if (db_get(sp, lno, DBG_FATAL, &p, &len))
228 		return (1);
229 
230 	/* Create a TEXT structure that can hold the entire line. */
231 	if ((tp = text_init(sp, NULL, 0, len)) == NULL)
232 		return (1);
233 
234 	/*
235 	 * If the line isn't empty and it's not the entire line,
236 	 * copy the portion we want, and reset the TEXT length.
237 	 */
238 	if (len != 0) {
239 		if (clen == ENTIRE_LINE)
240 			clen = len - fcno;
241 		MEMCPY(tp->lb, p + fcno, clen);
242 		tp->len = clen;
243 	}
244 
245 	/* Append to the end of the cut buffer. */
246 	TAILQ_INSERT_TAIL(cbp->textq, tp, q);
247 	cbp->len += tp->len;
248 
249 	return (0);
250 }
251 
252 /*
253  * cut_close --
254  *	Discard all cut buffers.
255  *
256  * PUBLIC: void cut_close(GS *);
257  */
258 void
259 cut_close(GS *gp)
260 {
261 	CB *cbp;
262 
263 	/* Free cut buffer list. */
264 	while ((cbp = SLIST_FIRST(gp->cutq)) != NULL) {
265 		if (!TAILQ_EMPTY(cbp->textq))
266 			text_lfree(cbp->textq);
267 		SLIST_REMOVE_HEAD(gp->cutq, q);
268 		free(cbp);
269 	}
270 
271 	/* Free default cut storage. */
272 	cbp = &gp->dcb_store;
273 	if (!TAILQ_EMPTY(cbp->textq))
274 		text_lfree(cbp->textq);
275 }
276 
277 /*
278  * text_init --
279  *	Allocate a new TEXT structure.
280  *
281  * PUBLIC: TEXT *text_init(SCR *, const CHAR_T *, size_t, size_t);
282  */
283 TEXT *
284 text_init(SCR *sp, const CHAR_T *p, size_t len, size_t total_len)
285 {
286 	TEXT *tp;
287 
288 	CALLOC(sp, tp, 1, sizeof(TEXT));
289 	if (tp == NULL)
290 		return (NULL);
291 	/* ANSI C doesn't define a call to malloc(3) for 0 bytes. */
292 	if ((tp->lb_len = total_len * sizeof(CHAR_T)) != 0) {
293 		MALLOC(sp, tp->lb, tp->lb_len);
294 		if (tp->lb == NULL) {
295 			free(tp);
296 			return (NULL);
297 		}
298 		if (p != NULL && len != 0)
299 			MEMCPY(tp->lb, p, len);
300 	}
301 	tp->len = len;
302 	return (tp);
303 }
304 
305 /*
306  * text_lfree --
307  *	Free a chain of text structures.
308  *
309  * PUBLIC: void text_lfree(TEXTH *);
310  */
311 void
312 text_lfree(TEXTH *headp)
313 {
314 	TEXT *tp;
315 
316 	while ((tp = TAILQ_FIRST(headp)) != NULL) {
317 		TAILQ_REMOVE(headp, tp, q);
318 		text_free(tp);
319 	}
320 }
321 
322 /*
323  * text_free --
324  *	Free a text structure.
325  *
326  * PUBLIC: void text_free(TEXT *);
327  */
328 void
329 text_free(TEXT *tp)
330 {
331 	free(tp->lb);
332 	free(tp);
333 }
334