Annotation of mandoc/apropos_db.c, Revision 1.16
1.16 ! kristaps 1: /* $Id: apropos_db.c,v 1.15 2011/11/28 09:44:05 schwarze Exp $ */
1.1 schwarze 2: /*
3: * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
1.3 schwarze 4: * Copyright (c) 2011 Ingo Schwarze <schwarze@openbsd.org>
1.1 schwarze 5: *
6: * Permission to use, copy, modify, and distribute this software for any
7: * purpose with or without fee is hereby granted, provided that the above
8: * copyright notice and this permission notice appear in all copies.
9: *
10: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17: */
18: #include <assert.h>
19: #include <fcntl.h>
20: #include <regex.h>
21: #include <stdarg.h>
1.6 kristaps 22: #include <stdint.h>
1.1 schwarze 23: #include <stdlib.h>
24: #include <string.h>
1.8 kristaps 25: #include <unistd.h>
1.1 schwarze 26:
27: #ifdef __linux__
28: # include <db_185.h>
29: #else
30: # include <db.h>
31: #endif
32:
1.2 schwarze 33: #include "mandocdb.h"
1.1 schwarze 34: #include "apropos_db.h"
35: #include "mandoc.h"
36:
1.5 kristaps 37: struct rec {
38: struct res res; /* resulting record info */
39: /*
40: * Maintain a binary tree for checking the uniqueness of `rec'
41: * when adding elements to the results array.
42: * Since the results array is dynamic, use offset in the array
43: * instead of a pointer to the structure.
44: */
45: int lhs;
46: int rhs;
47: int matched; /* expression is true */
48: int *matches; /* partial truth evaluations */
49: };
50:
1.1 schwarze 51: struct expr {
1.5 kristaps 52: int regex; /* is regex? */
53: int index; /* index in match array */
1.6 kristaps 54: uint64_t mask; /* type-mask */
1.5 kristaps 55: int and; /* is rhs of logical AND? */
56: char *v; /* search value */
57: regex_t re; /* compiled re, if regex */
58: struct expr *next; /* next in sequence */
59: struct expr *subexpr;
1.1 schwarze 60: };
61:
62: struct type {
1.6 kristaps 63: uint64_t mask;
1.1 schwarze 64: const char *name;
65: };
66:
1.8 kristaps 67: struct rectree {
68: struct rec *node; /* record array for dir tree */
69: int len; /* length of record array */
70: };
71:
1.1 schwarze 72: static const struct type types[] = {
1.7 kristaps 73: { TYPE_An, "An" },
74: { TYPE_Ar, "Ar" },
75: { TYPE_At, "At" },
76: { TYPE_Bsx, "Bsx" },
77: { TYPE_Bx, "Bx" },
78: { TYPE_Cd, "Cd" },
79: { TYPE_Cm, "Cm" },
80: { TYPE_Dv, "Dv" },
81: { TYPE_Dx, "Dx" },
82: { TYPE_Em, "Em" },
83: { TYPE_Er, "Er" },
84: { TYPE_Ev, "Ev" },
85: { TYPE_Fa, "Fa" },
86: { TYPE_Fl, "Fl" },
87: { TYPE_Fn, "Fn" },
88: { TYPE_Fn, "Fo" },
89: { TYPE_Ft, "Ft" },
90: { TYPE_Fx, "Fx" },
91: { TYPE_Ic, "Ic" },
92: { TYPE_In, "In" },
93: { TYPE_Lb, "Lb" },
94: { TYPE_Li, "Li" },
95: { TYPE_Lk, "Lk" },
96: { TYPE_Ms, "Ms" },
97: { TYPE_Mt, "Mt" },
98: { TYPE_Nd, "Nd" },
99: { TYPE_Nm, "Nm" },
100: { TYPE_Nx, "Nx" },
101: { TYPE_Ox, "Ox" },
102: { TYPE_Pa, "Pa" },
103: { TYPE_Rs, "Rs" },
104: { TYPE_Sh, "Sh" },
105: { TYPE_Ss, "Ss" },
106: { TYPE_St, "St" },
107: { TYPE_Sy, "Sy" },
108: { TYPE_Tn, "Tn" },
109: { TYPE_Va, "Va" },
110: { TYPE_Va, "Vt" },
111: { TYPE_Xr, "Xr" },
1.2 schwarze 112: { INT_MAX, "any" },
1.1 schwarze 113: { 0, NULL }
114: };
115:
116: static DB *btree_open(void);
1.12 schwarze 117: static int btree_read(const DBT *,
1.5 kristaps 118: const struct mchars *, char **);
119: static int expreval(const struct expr *, int *);
1.12 schwarze 120: static void exprexec(const struct expr *,
1.6 kristaps 121: const char *, uint64_t, struct rec *);
1.12 schwarze 122: static int exprmark(const struct expr *,
1.6 kristaps 123: const char *, uint64_t, int *);
1.5 kristaps 124: static struct expr *exprexpr(int, char *[], int *, int *, size_t *);
125: static struct expr *exprterm(char *, int);
1.1 schwarze 126: static DB *index_open(void);
1.11 kristaps 127: static int index_read(const DBT *, const DBT *, int,
1.1 schwarze 128: const struct mchars *, struct rec *);
129: static void norm_string(const char *,
130: const struct mchars *, char **);
131: static size_t norm_utf8(unsigned int, char[7]);
1.5 kristaps 132: static void recfree(struct rec *);
1.8 kristaps 133: static int single_search(struct rectree *, const struct opts *,
134: const struct expr *, size_t terms,
1.11 kristaps 135: struct mchars *, int);
1.1 schwarze 136:
137: /*
138: * Open the keyword mandoc-db database.
139: */
140: static DB *
141: btree_open(void)
142: {
143: BTREEINFO info;
144: DB *db;
145:
146: memset(&info, 0, sizeof(BTREEINFO));
147: info.flags = R_DUP;
148:
1.2 schwarze 149: db = dbopen(MANDOC_DB, O_RDONLY, 0, DB_BTREE, &info);
1.12 schwarze 150: if (NULL != db)
1.1 schwarze 151: return(db);
152:
153: return(NULL);
154: }
155:
156: /*
157: * Read a keyword from the database and normalise it.
158: * Return 0 if the database is insane, else 1.
159: */
160: static int
161: btree_read(const DBT *v, const struct mchars *mc, char **buf)
162: {
163:
164: /* Sanity: are we nil-terminated? */
165:
166: assert(v->size > 0);
1.6 kristaps 167:
1.1 schwarze 168: if ('\0' != ((char *)v->data)[(int)v->size - 1])
169: return(0);
170:
171: norm_string((char *)v->data, mc, buf);
172: return(1);
173: }
174:
175: /*
176: * Take a Unicode codepoint and produce its UTF-8 encoding.
177: * This isn't the best way to do this, but it works.
1.12 schwarze 178: * The magic numbers are from the UTF-8 packaging.
1.1 schwarze 179: * They're not as scary as they seem: read the UTF-8 spec for details.
180: */
181: static size_t
182: norm_utf8(unsigned int cp, char out[7])
183: {
184: size_t rc;
185:
186: rc = 0;
187:
188: if (cp <= 0x0000007F) {
189: rc = 1;
190: out[0] = (char)cp;
191: } else if (cp <= 0x000007FF) {
192: rc = 2;
193: out[0] = (cp >> 6 & 31) | 192;
194: out[1] = (cp & 63) | 128;
195: } else if (cp <= 0x0000FFFF) {
196: rc = 3;
197: out[0] = (cp >> 12 & 15) | 224;
198: out[1] = (cp >> 6 & 63) | 128;
199: out[2] = (cp & 63) | 128;
200: } else if (cp <= 0x001FFFFF) {
201: rc = 4;
202: out[0] = (cp >> 18 & 7) | 240;
203: out[1] = (cp >> 12 & 63) | 128;
204: out[2] = (cp >> 6 & 63) | 128;
205: out[3] = (cp & 63) | 128;
206: } else if (cp <= 0x03FFFFFF) {
207: rc = 5;
208: out[0] = (cp >> 24 & 3) | 248;
209: out[1] = (cp >> 18 & 63) | 128;
210: out[2] = (cp >> 12 & 63) | 128;
211: out[3] = (cp >> 6 & 63) | 128;
212: out[4] = (cp & 63) | 128;
213: } else if (cp <= 0x7FFFFFFF) {
214: rc = 6;
215: out[0] = (cp >> 30 & 1) | 252;
216: out[1] = (cp >> 24 & 63) | 128;
217: out[2] = (cp >> 18 & 63) | 128;
218: out[3] = (cp >> 12 & 63) | 128;
219: out[4] = (cp >> 6 & 63) | 128;
220: out[5] = (cp & 63) | 128;
221: } else
222: return(0);
223:
224: out[rc] = '\0';
225: return(rc);
226: }
227:
228: /*
229: * Normalise strings from the index and database.
230: * These strings are escaped as defined by mandoc_char(7) along with
231: * other goop in mandoc.h (e.g., soft hyphens).
232: * This function normalises these into a nice UTF-8 string.
233: * Returns 0 if the database is fucked.
234: */
235: static void
236: norm_string(const char *val, const struct mchars *mc, char **buf)
237: {
238: size_t sz, bsz;
239: char utfbuf[7];
240: const char *seq, *cpp;
241: int len, u, pos;
242: enum mandoc_esc esc;
1.12 schwarze 243: static const char res[] = { '\\', '\t',
1.1 schwarze 244: ASCII_NBRSP, ASCII_HYPH, '\0' };
245:
246: /* Pre-allocate by the length of the input */
247:
248: bsz = strlen(val) + 1;
249: *buf = mandoc_realloc(*buf, bsz);
250: pos = 0;
251:
252: while ('\0' != *val) {
253: /*
254: * Halt on the first escape sequence.
255: * This also halts on the end of string, in which case
256: * we just copy, fallthrough, and exit the loop.
257: */
258: if ((sz = strcspn(val, res)) > 0) {
259: memcpy(&(*buf)[pos], val, sz);
260: pos += (int)sz;
261: val += (int)sz;
262: }
263:
264: if (ASCII_HYPH == *val) {
265: (*buf)[pos++] = '-';
266: val++;
267: continue;
268: } else if ('\t' == *val || ASCII_NBRSP == *val) {
269: (*buf)[pos++] = ' ';
270: val++;
271: continue;
272: } else if ('\\' != *val)
273: break;
274:
275: /* Read past the slash. */
276:
277: val++;
278: u = 0;
279:
280: /*
281: * Parse the escape sequence and see if it's a
282: * predefined character or special character.
283: */
284:
285: esc = mandoc_escape(&val, &seq, &len);
286: if (ESCAPE_ERROR == esc)
287: break;
288:
1.12 schwarze 289: /*
1.1 schwarze 290: * XXX - this just does UTF-8, but we need to know
291: * beforehand whether we should do text substitution.
292: */
293:
294: switch (esc) {
295: case (ESCAPE_SPECIAL):
296: if (0 != (u = mchars_spec2cp(mc, seq, len)))
297: break;
298: /* FALLTHROUGH */
299: default:
300: continue;
301: }
302:
303: /*
304: * If we have a Unicode codepoint, try to convert that
305: * to a UTF-8 byte string.
306: */
307:
308: cpp = utfbuf;
309: if (0 == (sz = norm_utf8(u, utfbuf)))
310: continue;
311:
312: /* Copy the rendered glyph into the stream. */
313:
314: sz = strlen(cpp);
315: bsz += sz;
316:
317: *buf = mandoc_realloc(*buf, bsz);
318:
319: memcpy(&(*buf)[pos], cpp, sz);
320: pos += (int)sz;
321: }
322:
323: (*buf)[pos] = '\0';
324: }
325:
326: /*
327: * Open the filename-index mandoc-db database.
328: * Returns NULL if opening failed.
329: */
330: static DB *
331: index_open(void)
332: {
333: DB *db;
334:
1.2 schwarze 335: db = dbopen(MANDOC_IDX, O_RDONLY, 0, DB_RECNO, NULL);
1.1 schwarze 336: if (NULL != db)
337: return(db);
338:
339: return(NULL);
340: }
341:
342: /*
343: * Safely unpack from an index file record into the structure.
344: * Returns 1 if an entry was unpacked, 0 if the database is insane.
345: */
346: static int
1.11 kristaps 347: index_read(const DBT *key, const DBT *val, int index,
1.1 schwarze 348: const struct mchars *mc, struct rec *rec)
349: {
350: size_t left;
351: char *np, *cp;
352:
353: #define INDEX_BREAD(_dst) \
354: do { \
355: if (NULL == (np = memchr(cp, '\0', left))) \
356: return(0); \
357: norm_string(cp, mc, &(_dst)); \
358: left -= (np - cp) + 1; \
359: cp = np + 1; \
360: } while (/* CONSTCOND */ 0)
361:
362: left = val->size;
363: cp = (char *)val->data;
364:
1.5 kristaps 365: rec->res.rec = *(recno_t *)key->data;
1.11 kristaps 366: rec->res.volume = index;
1.1 schwarze 367:
1.14 schwarze 368: INDEX_BREAD(rec->res.type);
1.5 kristaps 369: INDEX_BREAD(rec->res.file);
370: INDEX_BREAD(rec->res.cat);
371: INDEX_BREAD(rec->res.title);
372: INDEX_BREAD(rec->res.arch);
373: INDEX_BREAD(rec->res.desc);
1.1 schwarze 374: return(1);
375: }
376:
377: /*
1.10 kristaps 378: * Search mandocdb databases in paths for expression "expr".
1.1 schwarze 379: * Filter out by "opts".
380: * Call "res" with the results, which may be zero.
1.5 kristaps 381: * Return 0 if there was a database error, else return 1.
1.1 schwarze 382: */
1.5 kristaps 383: int
1.10 kristaps 384: apropos_search(int pathsz, char **paths, const struct opts *opts,
1.12 schwarze 385: const struct expr *expr, size_t terms, void *arg,
1.5 kristaps 386: void (*res)(struct res *, size_t, void *))
1.1 schwarze 387: {
1.8 kristaps 388: struct rectree tree;
389: struct mchars *mc;
390: struct res *ress;
391: int i, mlen, rc;
392:
393: memset(&tree, 0, sizeof(struct rectree));
394:
1.10 kristaps 395: rc = 0;
1.8 kristaps 396: mc = mchars_alloc();
397:
1.10 kristaps 398: /*
399: * Main loop. Change into the directory containing manpage
400: * databases. Run our expession over each database in the set.
401: */
402:
403: for (i = 0; i < pathsz; i++) {
404: if (chdir(paths[i]))
1.8 kristaps 405: continue;
1.11 kristaps 406: if ( ! single_search(&tree, opts, expr, terms, mc, i))
1.10 kristaps 407: goto out;
1.8 kristaps 408: }
409:
410: /*
1.10 kristaps 411: * Count matching files, transfer to a "clean" array, then feed
412: * them to the output handler.
1.8 kristaps 413: */
414:
415: for (mlen = i = 0; i < tree.len; i++)
416: if (tree.node[i].matched)
417: mlen++;
418:
419: ress = mandoc_malloc(mlen * sizeof(struct res));
420:
421: for (mlen = i = 0; i < tree.len; i++)
422: if (tree.node[i].matched)
1.12 schwarze 423: memcpy(&ress[mlen++], &tree.node[i].res,
1.8 kristaps 424: sizeof(struct res));
425:
426: (*res)(ress, mlen, arg);
427: free(ress);
428:
1.10 kristaps 429: rc = 1;
430: out:
1.8 kristaps 431: for (i = 0; i < tree.len; i++)
432: recfree(&tree.node[i]);
433:
434: free(tree.node);
435: mchars_free(mc);
436: return(rc);
437: }
438:
439: static int
440: single_search(struct rectree *tree, const struct opts *opts,
441: const struct expr *expr, size_t terms,
1.11 kristaps 442: struct mchars *mc, int vol)
1.8 kristaps 443: {
444: int root, leaf, ch;
1.6 kristaps 445: uint64_t mask;
1.1 schwarze 446: DBT key, val;
447: DB *btree, *idx;
448: char *buf;
449: recno_t rec;
1.5 kristaps 450: struct rec *rs;
451: struct rec r;
1.6 kristaps 452: struct db_val *vbuf;
1.1 schwarze 453:
454: root = -1;
455: leaf = -1;
456: btree = NULL;
457: idx = NULL;
458: buf = NULL;
1.8 kristaps 459: rs = tree->node;
1.1 schwarze 460:
1.5 kristaps 461: memset(&r, 0, sizeof(struct rec));
1.1 schwarze 462:
1.12 schwarze 463: if (NULL == (btree = btree_open()))
1.10 kristaps 464: return(1);
1.1 schwarze 465:
1.8 kristaps 466: if (NULL == (idx = index_open())) {
467: (*btree->close)(btree);
1.10 kristaps 468: return(1);
1.8 kristaps 469: }
1.1 schwarze 470:
471: while (0 == (ch = (*btree->seq)(btree, &key, &val, R_NEXT))) {
1.12 schwarze 472: if (key.size < 2 || sizeof(struct db_val) != val.size)
473: break;
1.1 schwarze 474: if ( ! btree_read(&key, mc, &buf))
475: break;
476:
1.6 kristaps 477: vbuf = val.data;
478: rec = vbuf->rec;
479: mask = vbuf->mask;
1.5 kristaps 480:
481: /*
482: * See if this keyword record matches any of the
483: * expressions we have stored.
484: */
485: if ( ! exprmark(expr, buf, mask, NULL))
1.1 schwarze 486: continue;
487:
488: /*
489: * O(log n) scan for prior records. Since a record
490: * number is unbounded, this has decent performance over
491: * a complex hash function.
492: */
493:
494: for (leaf = root; leaf >= 0; )
1.12 schwarze 495: if (rec > rs[leaf].res.rec &&
1.5 kristaps 496: rs[leaf].rhs >= 0)
497: leaf = rs[leaf].rhs;
1.12 schwarze 498: else if (rec < rs[leaf].res.rec &&
1.5 kristaps 499: rs[leaf].lhs >= 0)
500: leaf = rs[leaf].lhs;
1.12 schwarze 501: else
1.1 schwarze 502: break;
503:
1.5 kristaps 504: /*
505: * If we find a record, see if it has already evaluated
506: * to true. If it has, great, just keep going. If not,
507: * try to evaluate it now and continue anyway.
508: */
509:
510: if (leaf >= 0 && rs[leaf].res.rec == rec) {
511: if (0 == rs[leaf].matched)
512: exprexec(expr, buf, mask, &rs[leaf]);
1.1 schwarze 513: continue;
1.5 kristaps 514: }
1.1 schwarze 515:
516: /*
1.5 kristaps 517: * We have a new file to examine.
518: * Extract the manpage's metadata from the index
519: * database, then begin partial evaluation.
1.1 schwarze 520: */
521:
522: key.data = &rec;
523: key.size = sizeof(recno_t);
524:
525: if (0 != (*idx->get)(idx, &key, &val, 0))
526: break;
527:
1.5 kristaps 528: r.lhs = r.rhs = -1;
1.11 kristaps 529: if ( ! index_read(&key, &val, vol, mc, &r))
1.1 schwarze 530: break;
531:
1.5 kristaps 532: /* XXX: this should be elsewhere, I guess? */
533:
534: if (opts->cat && strcasecmp(opts->cat, r.res.cat))
1.1 schwarze 535: continue;
1.5 kristaps 536: if (opts->arch && strcasecmp(opts->arch, r.res.arch))
1.1 schwarze 537: continue;
538:
1.8 kristaps 539: tree->node = rs = mandoc_realloc
540: (rs, (tree->len + 1) * sizeof(struct rec));
1.1 schwarze 541:
1.8 kristaps 542: memcpy(&rs[tree->len], &r, sizeof(struct rec));
1.12 schwarze 543: rs[tree->len].matches =
1.8 kristaps 544: mandoc_calloc(terms, sizeof(int));
1.1 schwarze 545:
1.12 schwarze 546: exprexec(expr, buf, mask, &rs[tree->len]);
547:
1.1 schwarze 548: /* Append to our tree. */
549:
550: if (leaf >= 0) {
1.5 kristaps 551: if (rec > rs[leaf].res.rec)
1.8 kristaps 552: rs[leaf].rhs = tree->len;
1.1 schwarze 553: else
1.8 kristaps 554: rs[leaf].lhs = tree->len;
1.1 schwarze 555: } else
1.8 kristaps 556: root = tree->len;
1.12 schwarze 557:
1.5 kristaps 558: memset(&r, 0, sizeof(struct rec));
1.8 kristaps 559: tree->len++;
1.1 schwarze 560: }
1.12 schwarze 561:
1.8 kristaps 562: (*btree->close)(btree);
563: (*idx->close)(idx);
1.1 schwarze 564:
565: free(buf);
1.8 kristaps 566: return(1 == ch);
1.5 kristaps 567: }
568:
569: static void
570: recfree(struct rec *rec)
571: {
572:
573: free(rec->res.file);
574: free(rec->res.cat);
575: free(rec->res.title);
576: free(rec->res.arch);
577: free(rec->res.desc);
578:
579: free(rec->matches);
1.1 schwarze 580: }
581:
1.13 kristaps 582: /*
583: * Compile a list of straight-up terms.
584: * The arguments are re-written into ~[[:<:]]term[[:>:]], or "term"
585: * surrounded by word boundaries, then pumped through exprterm().
586: * Terms are case-insensitive.
587: * This emulates whatis(1) behaviour.
588: */
589: struct expr *
590: termcomp(int argc, char *argv[], size_t *tt)
591: {
592: char *buf;
593: int pos;
594: struct expr *e, *next;
595: size_t sz;
596:
597: buf = NULL;
598: e = NULL;
599: *tt = 0;
600:
1.15 schwarze 601: for (pos = argc - 1; pos >= 0; pos--) {
602: sz = strlen(argv[pos]) + 18;
1.13 kristaps 603: buf = mandoc_realloc(buf, sz);
1.15 schwarze 604: strlcpy(buf, "Nm~[[:<:]]", sz);
1.13 kristaps 605: strlcat(buf, argv[pos], sz);
606: strlcat(buf, "[[:>:]]", sz);
607: if (NULL == (next = exprterm(buf, 0))) {
608: free(buf);
609: exprfree(e);
610: return(NULL);
611: }
1.15 schwarze 612: next->next = e;
1.13 kristaps 613: e = next;
614: (*tt)++;
615: }
616:
617: free(buf);
618: return(e);
619: }
620:
621: /*
622: * Compile a sequence of logical expressions.
623: * See apropos.1 for a grammar of this sequence.
624: */
1.1 schwarze 625: struct expr *
1.5 kristaps 626: exprcomp(int argc, char *argv[], size_t *tt)
1.1 schwarze 627: {
1.5 kristaps 628: int pos, lvl;
629: struct expr *e;
630:
631: pos = lvl = 0;
632: *tt = 0;
633:
634: e = exprexpr(argc, argv, &pos, &lvl, tt);
635:
636: if (0 == lvl && pos >= argc)
637: return(e);
638:
639: exprfree(e);
640: return(NULL);
641: }
642:
643: /*
644: * Compile an array of tokens into an expression.
645: * An informal expression grammar is defined in apropos(1).
646: * Return NULL if we fail doing so. All memory will be cleaned up.
647: * Return the root of the expression sequence if alright.
648: */
649: static struct expr *
1.9 kristaps 650: exprexpr(int argc, char *argv[], int *pos, int *lvl, size_t *tt)
1.5 kristaps 651: {
652: struct expr *e, *first, *next;
653: int log;
654:
655: first = next = NULL;
656:
657: for ( ; *pos < argc; (*pos)++) {
658: e = next;
659:
660: /*
661: * Close out a subexpression.
662: */
663:
664: if (NULL != e && 0 == strcmp(")", argv[*pos])) {
665: if (--(*lvl) < 0)
666: goto err;
667: break;
668: }
669:
670: /*
671: * Small note: if we're just starting, don't let "-a"
672: * and "-o" be considered logical operators: they're
673: * just tokens unless pairwise joining, in which case we
674: * record their existence (or assume "OR").
675: */
676: log = 0;
677:
678: if (NULL != e && 0 == strcmp("-a", argv[*pos]))
1.12 schwarze 679: log = 1;
1.5 kristaps 680: else if (NULL != e && 0 == strcmp("-o", argv[*pos]))
681: log = 2;
682:
683: if (log > 0 && ++(*pos) >= argc)
684: goto err;
685:
686: /*
687: * Now we parse the term part. This can begin with
688: * "-i", in which case the expression is case
689: * insensitive.
690: */
691:
692: if (0 == strcmp("(", argv[*pos])) {
693: ++(*pos);
694: ++(*lvl);
695: next = mandoc_calloc(1, sizeof(struct expr));
696: next->subexpr = exprexpr(argc, argv, pos, lvl, tt);
697: if (NULL == next->subexpr) {
698: free(next);
699: next = NULL;
700: }
701: } else if (0 == strcmp("-i", argv[*pos])) {
702: if (++(*pos) >= argc)
703: goto err;
704: next = exprterm(argv[*pos], 0);
705: } else
706: next = exprterm(argv[*pos], 1);
707:
708: if (NULL == next)
709: goto err;
710:
711: next->and = log == 1;
712: next->index = (int)(*tt)++;
713:
714: /* Append to our chain of expressions. */
715:
716: if (NULL == first) {
717: assert(NULL == e);
718: first = next;
719: } else {
720: assert(NULL != e);
721: e->next = next;
722: }
723: }
724:
725: return(first);
726: err:
727: exprfree(first);
728: return(NULL);
729: }
730:
731: /*
732: * Parse a terminal expression with the grammar as defined in
733: * apropos(1).
734: * Return NULL if we fail the parse.
735: */
736: static struct expr *
737: exprterm(char *buf, int cs)
738: {
739: struct expr e;
1.1 schwarze 740: struct expr *p;
1.3 schwarze 741: char *key;
1.5 kristaps 742: int i;
743:
744: memset(&e, 0, sizeof(struct expr));
1.1 schwarze 745:
1.5 kristaps 746: /* Choose regex or substring match. */
1.3 schwarze 747:
1.4 kristaps 748: if (NULL == (e.v = strpbrk(buf, "=~"))) {
1.3 schwarze 749: e.regex = 0;
1.4 kristaps 750: e.v = buf;
1.3 schwarze 751: } else {
752: e.regex = '~' == *e.v;
753: *e.v++ = '\0';
754: }
1.1 schwarze 755:
1.5 kristaps 756: /* Determine the record types to search for. */
1.3 schwarze 757:
758: e.mask = 0;
1.4 kristaps 759: if (buf < e.v) {
760: while (NULL != (key = strsep(&buf, ","))) {
1.3 schwarze 761: i = 0;
762: while (types[i].mask &&
1.4 kristaps 763: strcmp(types[i].name, key))
1.3 schwarze 764: i++;
765: e.mask |= types[i].mask;
766: }
767: }
768: if (0 == e.mask)
769: e.mask = TYPE_Nm | TYPE_Nd;
1.1 schwarze 770:
1.5 kristaps 771: if (e.regex) {
1.13 kristaps 772: i = REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE);
1.5 kristaps 773: if (regcomp(&e.re, e.v, i))
774: return(NULL);
775: }
1.1 schwarze 776:
1.3 schwarze 777: e.v = mandoc_strdup(e.v);
1.1 schwarze 778:
779: p = mandoc_calloc(1, sizeof(struct expr));
780: memcpy(p, &e, sizeof(struct expr));
781: return(p);
782: }
783:
784: void
785: exprfree(struct expr *p)
786: {
1.5 kristaps 787: struct expr *pp;
1.12 schwarze 788:
1.5 kristaps 789: while (NULL != p) {
790: if (p->subexpr)
791: exprfree(p->subexpr);
792: if (p->regex)
793: regfree(&p->re);
794: free(p->v);
795: pp = p->next;
796: free(p);
797: p = pp;
798: }
799: }
1.1 schwarze 800:
1.5 kristaps 801: static int
1.12 schwarze 802: exprmark(const struct expr *p, const char *cp,
1.6 kristaps 803: uint64_t mask, int *ms)
1.5 kristaps 804: {
805:
806: for ( ; p; p = p->next) {
807: if (p->subexpr) {
808: if (exprmark(p->subexpr, cp, mask, ms))
809: return(1);
810: continue;
811: } else if ( ! (mask & p->mask))
812: continue;
1.1 schwarze 813:
1.5 kristaps 814: if (p->regex) {
815: if (regexec(&p->re, cp, 0, NULL, 0))
816: continue;
1.16 ! kristaps 817: } else if (NULL == strcasestr(cp, p->v))
! 818: continue;
1.5 kristaps 819:
820: if (NULL == ms)
821: return(1);
822: else
823: ms[p->index] = 1;
824: }
1.1 schwarze 825:
1.5 kristaps 826: return(0);
1.1 schwarze 827: }
828:
829: static int
1.5 kristaps 830: expreval(const struct expr *p, int *ms)
1.1 schwarze 831: {
1.5 kristaps 832: int match;
1.1 schwarze 833:
1.5 kristaps 834: /*
835: * AND has precedence over OR. Analysis is left-right, though
836: * it doesn't matter because there are no side-effects.
837: * Thus, step through pairwise ANDs and accumulate their Boolean
838: * evaluation. If we encounter a single true AND collection or
839: * standalone term, the whole expression is true (by definition
840: * of OR).
841: */
842:
843: for (match = 0; p && ! match; p = p->next) {
844: /* Evaluate a subexpression, if applicable. */
845: if (p->subexpr && ! ms[p->index])
846: ms[p->index] = expreval(p->subexpr, ms);
847:
848: match = ms[p->index];
849: for ( ; p->next && p->next->and; p = p->next) {
850: /* Evaluate a subexpression, if applicable. */
851: if (p->next->subexpr && ! ms[p->next->index])
1.12 schwarze 852: ms[p->next->index] =
1.5 kristaps 853: expreval(p->next->subexpr, ms);
854: match = match && ms[p->next->index];
855: }
856: }
857:
858: return(match);
859: }
860:
861: /*
862: * First, update the array of terms for which this expression evaluates
863: * to true.
864: * Second, logically evaluate all terms over the updated array of truth
865: * values.
866: * If this evaluates to true, mark the expression as satisfied.
867: */
868: static void
1.12 schwarze 869: exprexec(const struct expr *e, const char *cp,
1.6 kristaps 870: uint64_t mask, struct rec *r)
1.5 kristaps 871: {
1.1 schwarze 872:
1.5 kristaps 873: assert(0 == r->matched);
1.12 schwarze 874: exprmark(e, cp, mask, r->matches);
875: r->matched = expreval(e, r->matches);
1.1 schwarze 876: }
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