-
Notifications
You must be signed in to change notification settings - Fork 0
/
fences.c
489 lines (424 loc) · 9.32 KB
/
fences.c
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
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
/*
*
* fences.c
*
* Match up various fenceposts, like (), [], {}, */ /*, #if, #el, #en
*
* Most code probably by Dan Lawrence or Dave Conroy for MicroEMACS
* Extensions for vile by Paul Fox
*
* $Header: /usr/build/VCS/pgf-vile/RCS/fences.c,v 1.39 1996/03/24 13:38:16 pgf Exp $
*
*/
#include "estruct.h"
#include "edef.h"
#if OPT_CFENCE
#define CPP_UNKNOWN -1
#define CPP_IF 0
#define CPP_ELIF 1
#define CPP_ELSE 2
#define CPP_ENDIF 3
#define CurrentChar() \
(is_at_end_of_line(DOT) ? '\n' : char_at(DOT))
#define InDirection(sdir) \
((sdir == REVERSE) ? backchar(FALSE, 1) : forwchar(FALSE, 1))
#define PrevCharIs(c) (DOT.o > 0 && lgetc(DOT.l, DOT.o-1) == c)
#define NextCharIs(c) (DOT.o+1 < llength(DOT.l) && (lgetc(DOT.l, DOT.o+1) == c))
static int comment_fence(int sdir);
static int getfence (int ch, int sdir);
static int simple_fence(int sdir, int ch, int ofence);
static int
cpp_keyword(
LINE *lp,
int off)
{
char temp[NSTRING];
register char *d = temp;
register int n;
static const struct {
char *name;
int code;
} keyword_table[] = {
{ "if", CPP_IF },
{ "ifdef", CPP_IF },
{ "ifndef", CPP_IF },
{ "elif", CPP_ELIF },
{ "else", CPP_ELSE },
{ "endif", CPP_ENDIF }
};
while (off < llength(lp)) {
n = lgetc(lp,off++);
if ((d - temp < sizeof(temp)-2) && isident(n))
*d++ = (char)n;
else
break;
}
*d = EOS;
for (n = 0; n < TABLESIZE(keyword_table); n++)
if (!strcmp(temp, keyword_table[n].name))
return keyword_table[n].code;
return CPP_UNKNOWN;
}
static int
cpp_fence(
int sdir,
int key)
{
int count = 1;
int i, j, this;
/* patch: this should come from arguments */
if (key == CPP_ENDIF)
sdir = REVERSE;
else
sdir = FORWARD;
/* set up for scan */
if (sdir == REVERSE)
DOT.l = lback(DOT.l);
else
DOT.l = lforw(DOT.l);
while (count > 0 && !is_header_line(DOT, curbp)) {
if ((i = firstchar(DOT.l)) >= 0
&& lgetc(DOT.l,i) == '#'
&& (j = nextchar(DOT.l, i+1)) >= 0
&& ((this = cpp_keyword(DOT.l, j)) != CPP_UNKNOWN)) {
int done = FALSE;
switch (this) {
case CPP_IF:
if (sdir == FORWARD) {
count++;
} else {
done = ((count-- == 1) &&
(key != this));
if (done)
count = 0;
}
break;
case CPP_ELIF:
case CPP_ELSE:
done = ((sdir == FORWARD) && (count == 1));
if (done)
count = 0;
break;
case CPP_ENDIF:
if (sdir == FORWARD) {
done = (--count == 0);
} else {
count++;
}
}
if ((count <= 0) || done) {
DOT.o = i;
break;
}
}
if (sdir == REVERSE)
DOT.l = lback(DOT.l);
else
DOT.l = lforw(DOT.l);
if (is_header_line(DOT,curbp) || interrupted())
return FALSE;
}
if (count == 0) {
curwp->w_flag |= WFMOVE;
if (doingopcmd)
regionshape = FULLLINE;
return TRUE;
}
return FALSE;
}
/* the cursor is moved to a matching fence */
int
matchfence(int f, int n)
{
int s = getfence(0, (!f || n > 0) ? FORWARD:REVERSE);
if (s == FALSE)
kbd_alarm();
return s;
}
int
matchfenceback(int f, int n)
{
int s = getfence(0, (!f || n > 0) ? REVERSE:FORWARD);
if (s == FALSE)
kbd_alarm();
return s;
}
#define PAIRED_FENCE_CH -1
int
is_user_fence(int ch, int *sdirp)
{
char *fences = b_val_ptr(curbp,VAL_FENCES);
char *chp, och;
if (!ch)
return 0;
chp = strchr(fences, ch);
if (!chp)
return 0;
if ((chp - fences) & 1) {
/* look for the left fence */
och = chp[-1];
if (sdirp)
*sdirp = REVERSE;
} else {
/* look for the right fence */
och = chp[1];
if (sdirp)
*sdirp = FORWARD;
}
return och;
}
static int
getfence(
int ch, /* fence type to match against */
int sdir) /* direction to scan if we're not on a fence to begin with */
{
MARK oldpos; /* original pointer */
register int ofence = 0; /* open fence */
int s, i;
int key = CPP_UNKNOWN;
char *C_fences, *ptr;
int fch;
/* save the original cursor position */
oldpos = DOT;
/* ch may have been passed, if being used internally */
if (!ch) {
if ((i = firstchar(DOT.l)) < 0) /* offset of first nonblank */
return FALSE; /* line is entirely blank */
if (DOT.o <= i && (ch = lgetc(DOT.l,i)) == '#') {
if (llength(DOT.l) < i+3)
return FALSE;
} else if ((ch = char_at(DOT)) == '/' || ch == '*') {
/* EMPTY */;
} else if (sdir == FORWARD) {
/* get the current character */
if (oldpos.o < llength(oldpos.l)) {
do {
ch = char_at(oldpos);
} while(!is_user_fence(ch, (int *)0) &&
++oldpos.o < llength(oldpos.l));
}
if (is_at_end_of_line(oldpos)) {
return FALSE;
}
} else {
/* get the current character */
if (oldpos.o >= 0) {
do {
ch = char_at(oldpos);
} while(!is_user_fence(ch, (int *)0) &&
--oldpos.o >= 0);
}
if (oldpos.o < 0) {
return FALSE;
}
}
/* we've at least found a fence -- move us that far */
DOT.o = oldpos.o;
}
fch = ch;
/* is it a "special" fence char? */
C_fences = "/*#";
ptr = strchr(C_fences, ch);
if (!ptr) {
ofence = is_user_fence(ch, &sdir);
if (ofence)
fch = PAIRED_FENCE_CH;
}
/* setup proper matching fence */
switch (fch) {
case PAIRED_FENCE_CH:
/* NOTHING */
break;
case '#':
if ((i = firstchar(DOT.l)) < 0)
return FALSE; /* line is entirely blank */
if ((i = nextchar(DOT.l, i+1)) >= 0
&& ((key = cpp_keyword(DOT.l, i)) != CPP_UNKNOWN))
break;
return FALSE;
case '*':
ch = '/';
if (NextCharIs('/')) {
sdir = REVERSE;
forwchar(TRUE,1);
break;
} else if (PrevCharIs('/')) {
sdir = FORWARD;
backchar(TRUE,1);
if (doingopcmd)
pre_op_dot = DOT;
break;
}
return FALSE;
case '/':
if (NextCharIs('*')) {
sdir = FORWARD;
break;
} else if (PrevCharIs('*')) {
sdir = REVERSE;
break;
}
/* FALL THROUGH */
default:
return(FALSE);
}
/* ops are inclusive of the endpoint */
if (doingopcmd && sdir == REVERSE) {
forwchar(TRUE,1);
pre_op_dot = DOT;
backchar(TRUE,1);
}
if (key != CPP_UNKNOWN) { /* we're searching for a cpp keyword */
s = cpp_fence(sdir, key);
} else if (ch == '/') {
s = comment_fence(sdir);
} else {
s = simple_fence(sdir, ch, ofence);
}
if (s == TRUE)
return TRUE;
/* restore the current position */
DOT = oldpos;
return(FALSE);
}
static int
simple_fence(int sdir, int ch, int ofence)
{
int count = 1; /* Assmue that we're sitting at one end of the fence */
int c;
/* scan for fence */
while (InDirection(sdir) && !interrupted()) {
c = CurrentChar();
if (c == ch) {
++count;
} else if (c == ofence) {
if (--count <= 0)
break;
}
}
/* if count is zero, we have a match, move the sucker */
if (count <= 0) {
if (!doingopcmd || doingsweep)
sweephack = TRUE;
else if (sdir == FORWARD)
forwchar(TRUE,1);
curwp->w_flag |= WFMOVE;
return TRUE;
}
return FALSE;
}
static int
comment_fence(int sdir)
{
MARK comstartpos;
int found = FALSE;
int s = FALSE;
int first = TRUE;
comstartpos.l = null_ptr;
while (!found) {
if (!first && CurrentChar() == '/') {
/* is it a comment-end? */
if (PrevCharIs('*')) {
if (sdir == FORWARD) {
found = TRUE;
break;
} else if (comstartpos.l != null_ptr) {
DOT = comstartpos;
found = TRUE;
break;
} else {
return FALSE;
}
}
/* is it a comment start? */
if (sdir == REVERSE && NextCharIs('*')) {
/* remember where we are */
comstartpos = DOT;
}
}
s = InDirection(sdir);
if (s == FALSE) {
if (comstartpos.l != null_ptr) {
DOT = comstartpos;
found = TRUE;
break;
}
return FALSE;
}
if (interrupted())
return FALSE;
first = FALSE;
}
/* if found, move the sucker */
if (found && !first) {
if (!doingopcmd || doingsweep)
sweephack = TRUE;
else if (sdir == FORWARD)
forwchar(TRUE,1);
curwp->w_flag |= WFMOVE;
return TRUE;
}
return FALSE;
}
/* get the indent of the line containing the matching brace/paren. */
int
fmatchindent(int c)
{
int ind;
MK = DOT;
if (getfence(c,REVERSE) == FALSE) {
(void)gomark(FALSE,1);
return previndent((int *)0);
}
ind = indentlen(DOT.l);
(void)gomark(FALSE,1);
return ind;
}
/* Close fences are matched against their partners, and if
on screen the cursor briefly lights there */
void
fmatch(int rch)
{
MARK oldpos; /* original position */
register LINE *toplp; /* top line in current window */
register int count; /* current fence level count */
register char c; /* current character in scan */
int dir, lch;
int backcharfailed = FALSE;
/* get the matching left-fence char, if it exists */
lch = is_user_fence(rch, &dir);
if (lch == 0 || dir != REVERSE)
return;
/* first get the display update out there */
(void)update(FALSE);
/* save the original cursor position */
oldpos = DOT;
/* find the top line and set up for scan */
toplp = lback(curwp->w_line.l);
count = 1;
backchar(TRUE, 2);
/* scan back until we find it, or reach past the top of the window */
while (count > 0 && DOT.l != toplp) {
c = CurrentChar();
if (c == rch)
++count;
if (c == lch)
--count;
if (backchar(FALSE, 1) != TRUE) {
backcharfailed = TRUE;
break;
}
}
/* if count is zero, we have a match, display the sucker */
if (count == 0) {
if (!backcharfailed)
forwchar(FALSE, 1);
if (update(FALSE) == TRUE)
/* the idea is to leave the cursor there for about a
quarter of a second */
catnap(300, FALSE);
}
/* restore the current position */
DOT = oldpos;
}
#endif /* OPT_CFENCE */