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
|
// -*- C++ -*-
/* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
Written by James Clark (jjc@jclark.com)
This file is part of groff.
groff is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
groff is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License along
with groff; see the file COPYING. If not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include "posix.h"
#include "lib.h"
#include "errarg.h"
#include "error.h"
#include "cset.h"
#include "cmap.h"
#include "refid.h"
#include "search.h"
class file_buffer {
char *buffer;
char *bufend;
public:
file_buffer();
~file_buffer();
int load(int fd, const char *filename);
const char *get_start() const;
const char *get_end() const;
};
typedef unsigned char uchar;
static uchar map[256];
static uchar inv_map[256][3];
struct map_init {
map_init();
};
static map_init the_map_init;
map_init::map_init()
{
int i;
for (i = 0; i < 256; i++)
map[i] = csalnum(i) ? cmlower(i) : '\0';
for (i = 0; i < 256; i++) {
if (cslower(i)) {
inv_map[i][0] = i;
inv_map[i][1] = cmupper(i);
inv_map[i][2] = '\0';
}
else if (csdigit(i)) {
inv_map[i][0] = i;
inv_map[i][1] = 0;
}
else
inv_map[i][0] = '\0';
}
}
class bmpattern {
char *pat;
int len;
int delta[256];
public:
bmpattern(const char *pattern, int pattern_length);
~bmpattern();
const char *search(const char *p, const char *end) const;
int length() const;
};
bmpattern::bmpattern(const char *pattern, int pattern_length)
: len(pattern_length)
{
pat = new char[len];
int i;
for (i = 0; i < len; i++)
pat[i] = map[uchar(pattern[i])];
for (i = 0; i < 256; i++)
delta[i] = len;
for (i = 0; i < len; i++)
for (const unsigned char *inv = inv_map[uchar(pat[i])]; *inv; inv++)
delta[*inv] = len - i - 1;
}
const char *bmpattern::search(const char *buf, const char *end) const
{
int buflen = end - buf;
if (len > buflen)
return 0;
const char *strend;
if (buflen > len*4)
strend = end - len*4;
else
strend = buf;
const char *k = buf + len - 1;
const int *del = delta;
const char *pattern = pat;
for (;;) {
while (k < strend) {
int t = del[uchar(*k)];
if (!t)
break;
k += t;
k += del[uchar(*k)];
k += del[uchar(*k)];
}
while (k < end && del[uchar(*k)] != 0)
k++;
if (k == end)
break;
int j = len - 1;
const char *s = k;
for (;;) {
if (j == 0)
return s;
if (map[uchar(*--s)] != uchar(pattern[--j]))
break;
}
k++;
}
return 0;
}
bmpattern::~bmpattern()
{
a_delete pat;
}
inline int bmpattern::length() const
{
return len;
}
static const char *find_end(const char *bufend, const char *p);
const char *linear_searcher::search_and_check(const bmpattern *key,
const char *buf, const char *bufend, const char **start) const
{
assert(buf[-1] == '\n');
assert(bufend[-1] == '\n');
const char *ptr = buf;
for (;;) {
const char *found = key->search(ptr, bufend);
if (!found)
break;
if (check_match(buf, bufend, found, key->length(), &ptr, start))
return found;
}
return 0;
}
static const char *skip_field(const char *end, const char *p)
{
for (;;)
if (*p++ == '\n') {
if (p == end || *p == '%')
break;
const char *q;
for (q = p; *q == ' ' || *q == '\t'; q++)
;
if (*q == '\n')
break;
p = q + 1;
}
return p;
}
static const char *find_end(const char *bufend, const char *p)
{
for (;;)
if (*p++ == '\n') {
if (p == bufend)
break;
const char *q;
for (q = p; *q == ' ' || *q == '\t'; q++)
;
if (*q == '\n')
break;
p = q + 1;
}
return p;
}
int linear_searcher::check_match(const char *buf, const char *bufend,
const char *match, int matchlen,
const char **cont, const char **start) const
{
*cont = match + 1;
// The user is required to supply only the first truncate_len characters
// of the key. If truncate_len <= 0, he must supply all the key.
if ((truncate_len <= 0 || matchlen < truncate_len)
&& map[uchar(match[matchlen])] != '\0')
return 0;
// The character before the match must not be an alphanumeric
// character (unless the alphanumeric character follows one or two
// percent characters at the beginning of the line), nor must it be
// a percent character at the beginning of a line, nor a percent
// character following a percent character at the beginning of a
// line.
switch (match - buf) {
case 0:
break;
case 1:
if (match[-1] == '%' || map[uchar(match[-1])] != '\0')
return 0;
break;
case 2:
if (map[uchar(match[-1])] != '\0' && match[-2] != '%')
return 0;
if (match[-1] == '%'
&& (match[-2] == '\n' || match[-2] == '%'))
return 0;
break;
default:
if (map[uchar(match[-1])] != '\0'
&& !(match[-2] == '%'
&& (match[-3] == '\n'
|| (match[-3] == '%' && match[-4] == '\n'))))
return 0;
if (match[-1] == '%'
&& (match[-2] == '\n'
|| (match[-2] == '%' && match[-3] == '\n')))
return 0;
}
const char *p = match;
int had_percent = 0;
for (;;) {
if (*p == '\n') {
if (!had_percent && p[1] == '%') {
if (p[2] != '\0' && strchr(ignore_fields, p[2]) != 0) {
*cont = skip_field(bufend, match + matchlen);
return 0;
}
if (!start)
break;
had_percent = 1;
}
if (p <= buf) {
if (start)
*start = p + 1;
return 1;
}
const char *q;
for (q = p - 1; *q == ' ' || *q == '\t'; q--)
;
if (*q == '\n') {
if (start)
*start = p + 1;
break;
}
p = q;
}
p--;
}
return 1;
}
file_buffer::file_buffer()
: buffer(0), bufend(0)
{
}
file_buffer::~file_buffer()
{
a_delete buffer;
}
const char *file_buffer::get_start() const
{
return buffer ? buffer + 4 : 0;
}
const char *file_buffer::get_end() const
{
return bufend;
}
int file_buffer::load(int fd, const char *filename)
{
struct stat sb;
if (fstat(fd, &sb) < 0)
error("can't fstat `%1': %2", filename, strerror(errno));
else if (!S_ISREG(sb.st_mode))
error("`%1' is not a regular file", filename);
else {
// We need one character extra at the beginning for an additional newline
// used as a sentinel. We get 4 instead so that the read buffer will be
// word-aligned. This seems to make the read slightly faster. We also
// need one character at the end also for an additional newline used as a
// sentinel.
int size = int(sb.st_size);
buffer = new char[size + 4 + 1];
int nread = read(fd, buffer + 4, size);
if (nread < 0)
error("error reading `%1': %2", filename, strerror(errno));
else if (nread != size)
error("size of `%1' decreased", filename);
else {
char c;
nread = read(fd, &c, 1);
if (nread != 0)
error("size of `%1' increased", filename);
else if (memchr(buffer + 4, '\0', size < 1024 ? size : 1024) != 0)
error("database `%1' is a binary file", filename);
else {
close(fd);
buffer[3] = '\n';
bufend = buffer + 4 + size;
if (bufend[-1] != '\n')
*bufend++ = '\n';
return 1;
}
}
a_delete buffer;
buffer = 0;
}
close(fd);
return 0;
}
linear_searcher::linear_searcher(const char *query, int query_len,
const char *ign, int trunc)
: keys(0), nkeys(0), truncate_len(trunc), ignore_fields(ign)
{
const char *query_end = query + query_len;
int nk = 0;
const char *p;
for (p = query; p < query_end; p++)
if (map[uchar(*p)] != '\0'
&& (p[1] == '\0' || map[uchar(p[1])] == '\0'))
nk++;
if (nk == 0)
return;
keys = new bmpattern*[nk];
p = query;
for (;;) {
while (p < query_end && map[uchar(*p)] == '\0')
p++;
if (p == query_end)
break;
const char *start = p;
while (p < query_end && map[uchar(*p)] != '\0')
p++;
keys[nkeys++] = new bmpattern(start, p - start);
}
assert(nkeys <= nk);
if (nkeys == 0) {
a_delete keys;
keys = 0;
}
}
linear_searcher::~linear_searcher()
{
for (int i = 0; i < nkeys; i++)
delete keys[i];
a_delete keys;
}
int linear_searcher::search(const char *buffer, const char *bufend,
const char **startp, int *lengthp) const
{
assert(bufend - buffer > 0);
assert(buffer[-1] == '\n');
assert(bufend[-1] == '\n');
if (nkeys == 0)
return 0;
for (;;) {
const char *refstart;
const char *found = search_and_check(keys[0], buffer, bufend, &refstart);
if (!found)
break;
const char *refend = find_end(bufend, found + keys[0]->length());
int i;
for (i = 1; i < nkeys; i++)
if (!search_and_check(keys[i], refstart, refend))
break;
if (i >= nkeys) {
*startp = refstart;
*lengthp = refend - refstart;
return 1;
}
buffer = refend;
}
return 0;
}
class linear_search_item : public search_item {
file_buffer fbuf;
public:
linear_search_item(const char *filename, int fid);
~linear_search_item();
int load(int fd);
search_item_iterator *make_search_item_iterator(const char *);
friend class linear_search_item_iterator;
};
class linear_search_item_iterator : public search_item_iterator {
linear_search_item *lsi;
int pos;
public:
linear_search_item_iterator(linear_search_item *, const char *query);
~linear_search_item_iterator();
int next(const linear_searcher &, const char **ptr, int *lenp,
reference_id *ridp);
};
search_item *make_linear_search_item(int fd, const char *filename, int fid)
{
linear_search_item *item = new linear_search_item(filename, fid);
if (!item->load(fd)) {
delete item;
return 0;
}
else
return item;
}
linear_search_item::linear_search_item(const char *filename, int fid)
: search_item(filename, fid)
{
}
linear_search_item::~linear_search_item()
{
}
int linear_search_item::load(int fd)
{
return fbuf.load(fd, name);
}
search_item_iterator *linear_search_item::make_search_item_iterator(
const char *query)
{
return new linear_search_item_iterator(this, query);
}
linear_search_item_iterator::linear_search_item_iterator(
linear_search_item *p, const char *)
: lsi(p), pos(0)
{
}
linear_search_item_iterator::~linear_search_item_iterator()
{
}
int linear_search_item_iterator::next(const linear_searcher &searcher,
const char **startp, int *lengthp,
reference_id *ridp)
{
const char *bufstart = lsi->fbuf.get_start();
const char *bufend = lsi->fbuf.get_end();
const char *ptr = bufstart + pos;
if (ptr < bufend && searcher.search(ptr, bufend, startp, lengthp)) {
pos = *startp + *lengthp - bufstart;
if (ridp)
*ridp = reference_id(lsi->filename_id, *startp - bufstart);
return 1;
}
else
return 0;
}
|