aboutsummaryrefslogtreecommitdiffstats
path: root/usr.bin/vi/vi/getc.c
blob: 67aee2ff46925b5593affbd48a960742662d0666 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
/*-
 * Copyright (c) 1992, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)getc.c	8.8 (Berkeley) 3/8/94";
#endif /* not lint */

#include <sys/types.h>
#include <queue.h>
#include <sys/time.h>

#include <bitstring.h>
#include <ctype.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <termios.h>

#include <db.h>
#include <regex.h>

#include "vi.h"
#include "vcmd.h"

/*
 * Character stream routines --
 *	These routines return the file a character at a time.  There are two
 *	special cases.  First, the end of a line, end of a file, start of a
 *	file and empty lines are returned as special cases, and no character
 *	is returned.  Second, empty lines include lines that have only white
 *	space in them, because the vi search functions don't care about white
 *	space, and this makes it easier for them to be consistent.
 */

/*
 * cs_init --
 *	Initialize character stream routines.
 */
int
cs_init(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	recno_t lno;

	if ((csp->cs_bp =
	    file_gline(sp, ep, csp->cs_lno, &csp->cs_len)) == NULL) {
		if (file_lline(sp, ep, &lno))
			return (1);
		if (lno == 0)
			msgq(sp, M_BERR, "Empty file.");
		else
			GETLINE_ERR(sp, csp->cs_lno);
		return (1);
	}
	if (csp->cs_len == 0 || v_isempty(csp->cs_bp, csp->cs_len)) {
		csp->cs_cno = 0;
		csp->cs_flags = CS_EMP;
	} else {
		csp->cs_flags = 0;
		csp->cs_ch = csp->cs_bp[csp->cs_cno];
	}
	return (0);
}

/*
 * cs_next --
 *	Retrieve the next character.
 */
int
cs_next(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	recno_t slno;

	switch (csp->cs_flags) {
	case CS_EMP:				/* EMP; get next line. */
	case CS_EOL:				/* EOL; get next line. */
		slno = csp->cs_lno;		/* Save current line. */
		if ((csp->cs_bp =
		    file_gline(sp, ep, ++csp->cs_lno, &csp->cs_len)) == NULL) {
			csp->cs_lno = slno;
			if (file_lline(sp, ep, &slno))
				return (1);
			if (slno > csp->cs_lno) {
				GETLINE_ERR(sp, csp->cs_lno);
				return (1);
			}
			csp->cs_flags = CS_EOF;
		} else if (csp->cs_len == 0 ||
		    v_isempty(csp->cs_bp, csp->cs_len)) {
			csp->cs_cno = 0;
			csp->cs_flags = CS_EMP;
		} else {
			csp->cs_flags = 0;
			csp->cs_ch = csp->cs_bp[csp->cs_cno = 0];
		}
		break;
	case 0:
		if (csp->cs_cno == csp->cs_len - 1)
			csp->cs_flags = CS_EOL;
		else
			csp->cs_ch = csp->cs_bp[++csp->cs_cno];
		break;
	case CS_EOF:				/* EOF. */
		break;
	default:
		abort();
		/* NOTREACHED */
	}
	return (0);
}

/*
 * cs_fspace --
 *	If on a space, eat forward until something other than a
 *	whitespace character.
 *
 * XXX
 * Semantics of checking the current character were coded for the fword()
 * function -- once the other word routines are converted, they may have
 * to change.
 */
int
cs_fspace(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	if (csp->cs_flags != 0 || !isblank(csp->cs_ch))
		return (0);
	for (;;) {
		if (cs_next(sp, ep, csp))
			return (1);
		if (csp->cs_flags != 0 || !isblank(csp->cs_ch))
			break;
	}
	return (0);
}

/*
 * cs_fblank --
 *	Eat forward to the next non-whitespace character.
 */
int
cs_fblank(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	for (;;) {
		if (cs_next(sp, ep, csp))
			return (1);
		if (csp->cs_flags == CS_EOL || csp->cs_flags == CS_EMP ||
		    csp->cs_flags == 0 && isblank(csp->cs_ch))
			continue;
		break;
	}
	return (0);
}

/*
 * cs_prev --
 *	Retrieve the previous character.
 */
int
cs_prev(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	recno_t slno;

	switch (csp->cs_flags) {
	case CS_EMP:				/* EMP; get previous line. */
	case CS_EOL:				/* EOL; get previous line. */
		if (csp->cs_lno == 1) {		/* SOF. */
			csp->cs_flags = CS_SOF;
			break;
		}
		slno = csp->cs_lno;		/* Save current line. */
		if ((csp->cs_bp =		/* Line should exist. */
		    file_gline(sp, ep, --csp->cs_lno, &csp->cs_len)) == NULL) {
			GETLINE_ERR(sp, csp->cs_lno);
			csp->cs_lno = slno;
			return (1);
		}
		if (csp->cs_len == 0 || v_isempty(csp->cs_bp, csp->cs_len)) {
			csp->cs_cno = 0;
			csp->cs_flags = CS_EMP;
		} else {
			csp->cs_flags = 0;
			csp->cs_cno = csp->cs_len - 1;
			csp->cs_ch = csp->cs_bp[csp->cs_cno];
		}
		break;
	case 0:
		if (csp->cs_cno == 0)
			if (csp->cs_lno == 1)
				csp->cs_flags = CS_SOF;
			else
				csp->cs_flags = CS_EOL;
		else
			csp->cs_ch = csp->cs_bp[--csp->cs_cno];
		break;
	case CS_SOF:				/* SOF. */
		break;
	default:
		abort();
		/* NOTREACHED */
	}
	return (0);
}

/*
 * cs_bblank --
 *	Eat backward to the next non-whitespace character.
 */
int
cs_bblank(sp, ep, csp)
	SCR *sp;
	EXF *ep;
	VCS *csp;
{
	for (;;) {
		if (cs_prev(sp, ep, csp))
			return (1);
		if (csp->cs_flags == CS_EOL || csp->cs_flags == CS_EMP ||
		    csp->cs_flags == 0 && isblank(csp->cs_ch))
			continue;
		break;
	}
	return (0);
}