1#include "cache.h"
2#include <regex.h>
3#include "grep.h"
4void append_grep_pattern(struct grep_opt *opt, const char *pat,
6 const char *origin, int no, enum grep_pat_token t)
7{
8 struct grep_pat *p = xcalloc(1, sizeof(*p));
9 p->pattern = pat;
10 p->origin = origin;
11 p->no = no;
12 p->token = t;
13 *opt->pattern_tail = p;
14 opt->pattern_tail = &p->next;
15 p->next = NULL;
16}
17static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
19{
20 int err = regcomp(&p->regexp, p->pattern, opt->regflags);
21 if (err) {
22 char errbuf[1024];
23 char where[1024];
24 if (p->no)
25 sprintf(where, "In '%s' at %d, ",
26 p->origin, p->no);
27 else if (p->origin)
28 sprintf(where, "%s, ", p->origin);
29 else
30 where[0] = 0;
31 regerror(err, &p->regexp, errbuf, 1024);
32 regfree(&p->regexp);
33 die("%s'%s': %s", where, p->pattern, errbuf);
34 }
35}
36static struct grep_expr *compile_pattern_or(struct grep_pat **);
38static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
39{
40 struct grep_pat *p;
41 struct grep_expr *x;
42 p = *list;
44 switch (p->token) {
45 case GREP_PATTERN: /* atom */
46 case GREP_PATTERN_HEAD:
47 case GREP_PATTERN_BODY:
48 x = xcalloc(1, sizeof (struct grep_expr));
49 x->node = GREP_NODE_ATOM;
50 x->u.atom = p;
51 *list = p->next;
52 return x;
53 case GREP_OPEN_PAREN:
54 *list = p->next;
55 x = compile_pattern_or(list);
56 if (!x)
57 return NULL;
58 if (!*list || (*list)->token != GREP_CLOSE_PAREN)
59 die("unmatched parenthesis");
60 *list = (*list)->next;
61 return x;
62 default:
63 return NULL;
64 }
65}
66static struct grep_expr *compile_pattern_not(struct grep_pat **list)
68{
69 struct grep_pat *p;
70 struct grep_expr *x;
71 p = *list;
73 switch (p->token) {
74 case GREP_NOT:
75 if (!p->next)
76 die("--not not followed by pattern expression");
77 *list = p->next;
78 x = xcalloc(1, sizeof (struct grep_expr));
79 x->node = GREP_NODE_NOT;
80 x->u.unary = compile_pattern_not(list);
81 if (!x->u.unary)
82 die("--not followed by non pattern expression");
83 return x;
84 default:
85 return compile_pattern_atom(list);
86 }
87}
88static struct grep_expr *compile_pattern_and(struct grep_pat **list)
90{
91 struct grep_pat *p;
92 struct grep_expr *x, *y, *z;
93 x = compile_pattern_not(list);
95 p = *list;
96 if (p && p->token == GREP_AND) {
97 if (!p->next)
98 die("--and not followed by pattern expression");
99 *list = p->next;
100 y = compile_pattern_and(list);
101 if (!y)
102 die("--and not followed by pattern expression");
103 z = xcalloc(1, sizeof (struct grep_expr));
104 z->node = GREP_NODE_AND;
105 z->u.binary.left = x;
106 z->u.binary.right = y;
107 return z;
108 }
109 return x;
110}
111static struct grep_expr *compile_pattern_or(struct grep_pat **list)
113{
114 struct grep_pat *p;
115 struct grep_expr *x, *y, *z;
116 x = compile_pattern_and(list);
118 p = *list;
119 if (x && p && p->token != GREP_CLOSE_PAREN) {
120 y = compile_pattern_or(list);
121 if (!y)
122 die("not a pattern expression %s", p->pattern);
123 z = xcalloc(1, sizeof (struct grep_expr));
124 z->node = GREP_NODE_OR;
125 z->u.binary.left = x;
126 z->u.binary.right = y;
127 return z;
128 }
129 return x;
130}
131static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
133{
134 return compile_pattern_or(list);
135}
136void compile_grep_patterns(struct grep_opt *opt)
138{
139 struct grep_pat *p;
140 if (opt->all_match)
142 opt->extended = 1;
143 for (p = opt->pattern_list; p; p = p->next) {
145 switch (p->token) {
146 case GREP_PATTERN: /* atom */
147 case GREP_PATTERN_HEAD:
148 case GREP_PATTERN_BODY:
149 if (!opt->fixed)
150 compile_regexp(p, opt);
151 break;
152 default:
153 opt->extended = 1;
154 break;
155 }
156 }
157 if (!opt->extended)
159 return;
160 /* Then bundle them up in an expression.
162 * A classic recursive descent parser would do.
163 */
164 p = opt->pattern_list;
165 opt->pattern_expression = compile_pattern_expr(&p);
166 if (p)
167 die("incomplete pattern expression: %s", p->pattern);
168}
169static void free_pattern_expr(struct grep_expr *x)
171{
172 switch (x->node) {
173 case GREP_NODE_ATOM:
174 break;
175 case GREP_NODE_NOT:
176 free_pattern_expr(x->u.unary);
177 break;
178 case GREP_NODE_AND:
179 case GREP_NODE_OR:
180 free_pattern_expr(x->u.binary.left);
181 free_pattern_expr(x->u.binary.right);
182 break;
183 }
184 free(x);
185}
186void free_grep_patterns(struct grep_opt *opt)
188{
189 struct grep_pat *p, *n;
190 for (p = opt->pattern_list; p; p = n) {
192 n = p->next;
193 switch (p->token) {
194 case GREP_PATTERN: /* atom */
195 case GREP_PATTERN_HEAD:
196 case GREP_PATTERN_BODY:
197 regfree(&p->regexp);
198 break;
199 default:
200 break;
201 }
202 free(p);
203 }
204 if (!opt->extended)
206 return;
207 free_pattern_expr(opt->pattern_expression);
208}
209static char *end_of_line(char *cp, unsigned long *left)
211{
212 unsigned long l = *left;
213 while (l && *cp != '\n') {
214 l--;
215 cp++;
216 }
217 *left = l;
218 return cp;
219}
220static int word_char(char ch)
222{
223 return isalnum(ch) || ch == '_';
224}
225static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
227 const char *name, unsigned lno, char sign)
228{
229 if (opt->pathname)
230 printf("%s%c", name, sign);
231 if (opt->linenum)
232 printf("%d%c", lno, sign);
233 printf("%.*s\n", (int)(eol-bol), bol);
234}
235/*
237 * NEEDSWORK: share code with diff.c
238 */
239#define FIRST_FEW_BYTES 8000
240static int buffer_is_binary(const char *ptr, unsigned long size)
241{
242 if (FIRST_FEW_BYTES < size)
243 size = FIRST_FEW_BYTES;
244 return !!memchr(ptr, 0, size);
245}
246static int fixmatch(const char *pattern, char *line, regmatch_t *match)
248{
249 char *hit = strstr(line, pattern);
250 if (!hit) {
251 match->rm_so = match->rm_eo = -1;
252 return REG_NOMATCH;
253 }
254 else {
255 match->rm_so = hit - line;
256 match->rm_eo = match->rm_so + strlen(pattern);
257 return 0;
258 }
259}
260static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
262{
263 int hit = 0;
264 int at_true_bol = 1;
265 regmatch_t pmatch[10];
266 if ((p->token != GREP_PATTERN) &&
268 ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
269 return 0;
270 again:
272 if (!opt->fixed) {
273 regex_t *exp = &p->regexp;
274 hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
275 pmatch, 0);
276 }
277 else {
278 hit = !fixmatch(p->pattern, bol, pmatch);
279 }
280 if (hit && opt->word_regexp) {
282 if ((pmatch[0].rm_so < 0) ||
283 (eol - bol) <= pmatch[0].rm_so ||
284 (pmatch[0].rm_eo < 0) ||
285 (eol - bol) < pmatch[0].rm_eo)
286 die("regexp returned nonsense");
287 /* Match beginning must be either beginning of the
289 * line, or at word boundary (i.e. the last char must
290 * not be a word char). Similarly, match end must be
291 * either end of the line, or at word boundary
292 * (i.e. the next char must not be a word char).
293 */
294 if ( ((pmatch[0].rm_so == 0 && at_true_bol) ||
295 !word_char(bol[pmatch[0].rm_so-1])) &&
296 ((pmatch[0].rm_eo == (eol-bol)) ||
297 !word_char(bol[pmatch[0].rm_eo])) )
298 ;
299 else
300 hit = 0;
301 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
303 /* There could be more than one match on the
304 * line, and the first match might not be
305 * strict word match. But later ones could be!
306 */
307 bol = pmatch[0].rm_so + bol + 1;
308 at_true_bol = 0;
309 goto again;
310 }
311 }
312 return hit;
313}
314static int match_expr_eval(struct grep_opt *o,
316 struct grep_expr *x,
317 char *bol, char *eol,
318 enum grep_context ctx,
319 int collect_hits)
320{
321 int h = 0;
322 switch (x->node) {
324 case GREP_NODE_ATOM:
325 h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
326 break;
327 case GREP_NODE_NOT:
328 h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
329 break;
330 case GREP_NODE_AND:
331 if (!collect_hits)
332 return (match_expr_eval(o, x->u.binary.left,
333 bol, eol, ctx, 0) &&
334 match_expr_eval(o, x->u.binary.right,
335 bol, eol, ctx, 0));
336 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
337 h &= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 0);
338 break;
339 case GREP_NODE_OR:
340 if (!collect_hits)
341 return (match_expr_eval(o, x->u.binary.left,
342 bol, eol, ctx, 0) ||
343 match_expr_eval(o, x->u.binary.right,
344 bol, eol, ctx, 0));
345 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
346 x->u.binary.left->hit |= h;
347 h |= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 1);
348 break;
349 default:
350 die("Unexpected node type (internal error) %d\n", x->node);
351 }
352 if (collect_hits)
353 x->hit |= h;
354 return h;
355}
356static int match_expr(struct grep_opt *opt, char *bol, char *eol,
358 enum grep_context ctx, int collect_hits)
359{
360 struct grep_expr *x = opt->pattern_expression;
361 return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
362}
363static int match_line(struct grep_opt *opt, char *bol, char *eol,
365 enum grep_context ctx, int collect_hits)
366{
367 struct grep_pat *p;
368 if (opt->extended)
369 return match_expr(opt, bol, eol, ctx, collect_hits);
370 /* we do not call with collect_hits without being extended */
372 for (p = opt->pattern_list; p; p = p->next) {
373 if (match_one_pattern(opt, p, bol, eol, ctx))
374 return 1;
375 }
376 return 0;
377}
378static int grep_buffer_1(struct grep_opt *opt, const char *name,
380 char *buf, unsigned long size, int collect_hits)
381{
382 char *bol = buf;
383 unsigned long left = size;
384 unsigned lno = 1;
385 struct pre_context_line {
386 char *bol;
387 char *eol;
388 } *prev = NULL, *pcl;
389 unsigned last_hit = 0;
390 unsigned last_shown = 0;
391 int binary_match_only = 0;
392 const char *hunk_mark = "";
393 unsigned count = 0;
394 enum grep_context ctx = GREP_CONTEXT_HEAD;
395 if (buffer_is_binary(buf, size)) {
397 switch (opt->binary) {
398 case GREP_BINARY_DEFAULT:
399 binary_match_only = 1;
400 break;
401 case GREP_BINARY_NOMATCH:
402 return 0; /* Assume unmatch */
403 break;
404 default:
405 break;
406 }
407 }
408 if (opt->pre_context)
410 prev = xcalloc(opt->pre_context, sizeof(*prev));
411 if (opt->pre_context || opt->post_context)
412 hunk_mark = "--\n";
413 while (left) {
415 char *eol, ch;
416 int hit;
417 eol = end_of_line(bol, &left);
419 ch = *eol;
420 *eol = 0;
421 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
423 ctx = GREP_CONTEXT_BODY;
424 hit = match_line(opt, bol, eol, ctx, collect_hits);
426 *eol = ch;
427 if (collect_hits)
429 goto next_line;
430 /* "grep -v -e foo -e bla" should list lines
432 * that do not have either, so inversion should
433 * be done outside.
434 */
435 if (opt->invert)
436 hit = !hit;
437 if (opt->unmatch_name_only) {
438 if (hit)
439 return 0;
440 goto next_line;
441 }
442 if (hit) {
443 count++;
444 if (opt->status_only)
445 return 1;
446 if (binary_match_only) {
447 printf("Binary file %s matches\n", name);
448 return 1;
449 }
450 if (opt->name_only) {
451 printf("%s\n", name);
452 return 1;
453 }
454 /* Hit at this line. If we haven't shown the
455 * pre-context lines, we would need to show them.
456 * When asked to do "count", this still show
457 * the context which is nonsense, but the user
458 * deserves to get that ;-).
459 */
460 if (opt->pre_context) {
461 unsigned from;
462 if (opt->pre_context < lno)
463 from = lno - opt->pre_context;
464 else
465 from = 1;
466 if (from <= last_shown)
467 from = last_shown + 1;
468 if (last_shown && from != last_shown + 1)
469 printf(hunk_mark);
470 while (from < lno) {
471 pcl = &prev[lno-from-1];
472 show_line(opt, pcl->bol, pcl->eol,
473 name, from, '-');
474 from++;
475 }
476 last_shown = lno-1;
477 }
478 if (last_shown && lno != last_shown + 1)
479 printf(hunk_mark);
480 if (!opt->count)
481 show_line(opt, bol, eol, name, lno, ':');
482 last_shown = last_hit = lno;
483 }
484 else if (last_hit &&
485 lno <= last_hit + opt->post_context) {
486 /* If the last hit is within the post context,
487 * we need to show this line.
488 */
489 if (last_shown && lno != last_shown + 1)
490 printf(hunk_mark);
491 show_line(opt, bol, eol, name, lno, '-');
492 last_shown = lno;
493 }
494 if (opt->pre_context) {
495 memmove(prev+1, prev,
496 (opt->pre_context-1) * sizeof(*prev));
497 prev->bol = bol;
498 prev->eol = eol;
499 }
500 next_line:
502 bol = eol + 1;
503 if (!left)
504 break;
505 left--;
506 lno++;
507 }
508 free(prev);
510 if (collect_hits)
511 return 0;
512 if (opt->status_only)
514 return 0;
515 if (opt->unmatch_name_only) {
516 /* We did not see any hit, so we want to show this */
517 printf("%s\n", name);
518 return 1;
519 }
520 /* NEEDSWORK:
522 * The real "grep -c foo *.c" gives many "bar.c:0" lines,
523 * which feels mostly useless but sometimes useful. Maybe
524 * make it another option? For now suppress them.
525 */
526 if (opt->count && count)
527 printf("%s:%u\n", name, count);
528 return !!last_hit;
529}
530static void clr_hit_marker(struct grep_expr *x)
532{
533 /* All-hit markers are meaningful only at the very top level
534 * OR node.
535 */
536 while (1) {
537 x->hit = 0;
538 if (x->node != GREP_NODE_OR)
539 return;
540 x->u.binary.left->hit = 0;
541 x = x->u.binary.right;
542 }
543}
544static int chk_hit_marker(struct grep_expr *x)
546{
547 /* Top level nodes have hit markers. See if they all are hits */
548 while (1) {
549 if (x->node != GREP_NODE_OR)
550 return x->hit;
551 if (!x->u.binary.left->hit)
552 return 0;
553 x = x->u.binary.right;
554 }
555}
556int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
558{
559 /*
560 * we do not have to do the two-pass grep when we do not check
561 * buffer-wide "all-match".
562 */
563 if (!opt->all_match)
564 return grep_buffer_1(opt, name, buf, size, 0);
565 /* Otherwise the toplevel "or" terms hit a bit differently.
567 * We first clear hit markers from them.
568 */
569 clr_hit_marker(opt->pattern_expression);
570 grep_buffer_1(opt, name, buf, size, 1);
571 if (!chk_hit_marker(opt->pattern_expression))
573 return 0;
574 return grep_buffer_1(opt, name, buf, size, 0);
576}