xref: /openbsd-src/usr.bin/vi/common/delete.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /*	$OpenBSD: delete.c,v 1.11 2016/01/06 22:28:52 millert 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 <errno.h>
19 #include <stdint.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 
24 #include "common.h"
25 
26 /*
27  * del --
28  *	Delete a range of text.
29  *
30  * PUBLIC: int del(SCR *, MARK *, MARK *, int);
31  */
32 int
33 del(SCR *sp, MARK *fm, MARK *tm, int lmode)
34 {
35 	recno_t lno;
36 	size_t blen, len, nlen, tlen;
37 	char *bp, *p;
38 	int eof, rval;
39 
40 	bp = NULL;
41 
42 	/* Case 1 -- delete in line mode. */
43 	if (lmode) {
44 		for (lno = tm->lno; lno >= fm->lno; --lno) {
45 			if (db_delete(sp, lno))
46 				return (1);
47 			++sp->rptlines[L_DELETED];
48 			if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
49 				break;
50 		}
51 		goto done;
52 	}
53 
54 	/*
55 	 * Case 2 -- delete to EOF.  This is a special case because it's
56 	 * easier to pick it off than try and find it in the other cases.
57  	 */
58 	if (db_last(sp, &lno))
59 		return (1);
60 	if (tm->lno >= lno) {
61 		if (tm->lno == lno) {
62 			if (db_get(sp, lno, DBG_FATAL, &p, &len))
63 				return (1);
64 			eof = tm->cno != -1 && tm->cno >= len ? 1 : 0;
65 		} else
66 			eof = 1;
67 		if (eof) {
68 			for (lno = tm->lno; lno > fm->lno; --lno) {
69 				if (db_delete(sp, lno))
70 					return (1);
71 				++sp->rptlines[L_DELETED];
72 				if (lno %
73 				    INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
74 					break;
75 			}
76 			if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
77 				return (1);
78 			GET_SPACE_RET(sp, bp, blen, fm->cno);
79 			memcpy(bp, p, fm->cno);
80 			if (db_set(sp, fm->lno, bp, fm->cno))
81 				return (1);
82 			goto done;
83 		}
84 	}
85 
86 	/* Case 3 -- delete within a single line. */
87 	if (tm->lno == fm->lno) {
88 		if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
89 			return (1);
90 		GET_SPACE_RET(sp, bp, blen, len);
91 		if (fm->cno != 0)
92 			memcpy(bp, p, fm->cno);
93 		memcpy(bp + fm->cno, p + (tm->cno + 1), len - (tm->cno + 1));
94 		if (db_set(sp, fm->lno,
95 		    bp, len - ((tm->cno - fm->cno) + 1)))
96 			goto err;
97 		goto done;
98 	}
99 
100 	/*
101 	 * Case 4 -- delete over multiple lines.
102 	 *
103 	 * Copy the start partial line into place.
104 	 */
105 	if ((tlen = fm->cno) != 0) {
106 		if (db_get(sp, fm->lno, DBG_FATAL, &p, NULL))
107 			return (1);
108 		GET_SPACE_RET(sp, bp, blen, tlen + 256);
109 		memcpy(bp, p, tlen);
110 	}
111 
112 	/* Copy the end partial line into place. */
113 	if (db_get(sp, tm->lno, DBG_FATAL, &p, &len))
114 		goto err;
115 	if (len != 0 && tm->cno != len - 1) {
116 		if (len < tm->cno + 1 || len - (tm->cno + 1) > SIZE_MAX - tlen) {
117 			msgq(sp, M_ERR, "Line length overflow");
118 			goto err;
119 		}
120 		nlen = (len - (tm->cno + 1)) + tlen;
121 		if (tlen == 0) {
122 			GET_SPACE_RET(sp, bp, blen, nlen);
123 		} else
124 			ADD_SPACE_RET(sp, bp, blen, nlen);
125 
126 		memcpy(bp + tlen, p + (tm->cno + 1), len - (tm->cno + 1));
127 		tlen += len - (tm->cno + 1);
128 	}
129 
130 	/* Set the current line. */
131 	if (db_set(sp, fm->lno, bp, tlen))
132 		goto err;
133 
134 	/* Delete the last and intermediate lines. */
135 	for (lno = tm->lno; lno > fm->lno; --lno) {
136 		if (db_delete(sp, lno))
137 			goto err;
138 		++sp->rptlines[L_DELETED];
139 		if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
140 			break;
141 	}
142 
143 done:	rval = 0;
144 	if (0)
145 err:		rval = 1;
146 	if (bp != NULL)
147 		FREE_SPACE(sp, bp, blen);
148 	return (rval);
149 }
150