fix parsing of @{-1}@{u} combination
[alt-git.git] / grep.c
blob60cce469f3be7c812bf24c4534e7321207b73a24
1 #include "cache.h"
2 #include "grep.h"
3 #include "userdiff.h"
4 #include "xdiff-interface.h"
6 void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field field, const char *pat)
8 struct grep_pat *p = xcalloc(1, sizeof(*p));
9 p->pattern = pat;
10 p->origin = "header";
11 p->no = 0;
12 p->token = GREP_PATTERN_HEAD;
13 p->field = field;
14 *opt->pattern_tail = p;
15 opt->pattern_tail = &p->next;
16 p->next = NULL;
19 void append_grep_pattern(struct grep_opt *opt, const char *pat,
20 const char *origin, int no, enum grep_pat_token t)
22 struct grep_pat *p = xcalloc(1, sizeof(*p));
23 p->pattern = pat;
24 p->origin = origin;
25 p->no = no;
26 p->token = t;
27 *opt->pattern_tail = p;
28 opt->pattern_tail = &p->next;
29 p->next = NULL;
32 struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
34 struct grep_pat *pat;
35 struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
36 *ret = *opt;
38 ret->pattern_list = NULL;
39 ret->pattern_tail = &ret->pattern_list;
41 for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
43 if(pat->token == GREP_PATTERN_HEAD)
44 append_header_grep_pattern(ret, pat->field,
45 pat->pattern);
46 else
47 append_grep_pattern(ret, pat->pattern, pat->origin,
48 pat->no, pat->token);
51 return ret;
54 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
56 int err;
58 p->word_regexp = opt->word_regexp;
59 p->ignore_case = opt->ignore_case;
61 if (opt->fixed)
62 p->fixed = 1;
63 if (opt->regflags & REG_ICASE)
64 p->fixed = 0;
65 if (p->fixed)
66 return;
68 err = regcomp(&p->regexp, p->pattern, opt->regflags);
69 if (err) {
70 char errbuf[1024];
71 char where[1024];
72 if (p->no)
73 sprintf(where, "In '%s' at %d, ",
74 p->origin, p->no);
75 else if (p->origin)
76 sprintf(where, "%s, ", p->origin);
77 else
78 where[0] = 0;
79 regerror(err, &p->regexp, errbuf, 1024);
80 regfree(&p->regexp);
81 die("%s'%s': %s", where, p->pattern, errbuf);
85 static struct grep_expr *compile_pattern_or(struct grep_pat **);
86 static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
88 struct grep_pat *p;
89 struct grep_expr *x;
91 p = *list;
92 if (!p)
93 return NULL;
94 switch (p->token) {
95 case GREP_PATTERN: /* atom */
96 case GREP_PATTERN_HEAD:
97 case GREP_PATTERN_BODY:
98 x = xcalloc(1, sizeof (struct grep_expr));
99 x->node = GREP_NODE_ATOM;
100 x->u.atom = p;
101 *list = p->next;
102 return x;
103 case GREP_OPEN_PAREN:
104 *list = p->next;
105 x = compile_pattern_or(list);
106 if (!*list || (*list)->token != GREP_CLOSE_PAREN)
107 die("unmatched parenthesis");
108 *list = (*list)->next;
109 return x;
110 default:
111 return NULL;
115 static struct grep_expr *compile_pattern_not(struct grep_pat **list)
117 struct grep_pat *p;
118 struct grep_expr *x;
120 p = *list;
121 if (!p)
122 return NULL;
123 switch (p->token) {
124 case GREP_NOT:
125 if (!p->next)
126 die("--not not followed by pattern expression");
127 *list = p->next;
128 x = xcalloc(1, sizeof (struct grep_expr));
129 x->node = GREP_NODE_NOT;
130 x->u.unary = compile_pattern_not(list);
131 if (!x->u.unary)
132 die("--not followed by non pattern expression");
133 return x;
134 default:
135 return compile_pattern_atom(list);
139 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
141 struct grep_pat *p;
142 struct grep_expr *x, *y, *z;
144 x = compile_pattern_not(list);
145 p = *list;
146 if (p && p->token == GREP_AND) {
147 if (!p->next)
148 die("--and not followed by pattern expression");
149 *list = p->next;
150 y = compile_pattern_and(list);
151 if (!y)
152 die("--and not followed by pattern expression");
153 z = xcalloc(1, sizeof (struct grep_expr));
154 z->node = GREP_NODE_AND;
155 z->u.binary.left = x;
156 z->u.binary.right = y;
157 return z;
159 return x;
162 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
164 struct grep_pat *p;
165 struct grep_expr *x, *y, *z;
167 x = compile_pattern_and(list);
168 p = *list;
169 if (x && p && p->token != GREP_CLOSE_PAREN) {
170 y = compile_pattern_or(list);
171 if (!y)
172 die("not a pattern expression %s", p->pattern);
173 z = xcalloc(1, sizeof (struct grep_expr));
174 z->node = GREP_NODE_OR;
175 z->u.binary.left = x;
176 z->u.binary.right = y;
177 return z;
179 return x;
182 static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
184 return compile_pattern_or(list);
187 void compile_grep_patterns(struct grep_opt *opt)
189 struct grep_pat *p;
191 if (opt->all_match)
192 opt->extended = 1;
194 for (p = opt->pattern_list; p; p = p->next) {
195 switch (p->token) {
196 case GREP_PATTERN: /* atom */
197 case GREP_PATTERN_HEAD:
198 case GREP_PATTERN_BODY:
199 compile_regexp(p, opt);
200 break;
201 default:
202 opt->extended = 1;
203 break;
207 if (!opt->extended)
208 return;
210 /* Then bundle them up in an expression.
211 * A classic recursive descent parser would do.
213 p = opt->pattern_list;
214 if (p)
215 opt->pattern_expression = compile_pattern_expr(&p);
216 if (p)
217 die("incomplete pattern expression: %s", p->pattern);
220 static void free_pattern_expr(struct grep_expr *x)
222 switch (x->node) {
223 case GREP_NODE_ATOM:
224 break;
225 case GREP_NODE_NOT:
226 free_pattern_expr(x->u.unary);
227 break;
228 case GREP_NODE_AND:
229 case GREP_NODE_OR:
230 free_pattern_expr(x->u.binary.left);
231 free_pattern_expr(x->u.binary.right);
232 break;
234 free(x);
237 void free_grep_patterns(struct grep_opt *opt)
239 struct grep_pat *p, *n;
241 for (p = opt->pattern_list; p; p = n) {
242 n = p->next;
243 switch (p->token) {
244 case GREP_PATTERN: /* atom */
245 case GREP_PATTERN_HEAD:
246 case GREP_PATTERN_BODY:
247 regfree(&p->regexp);
248 break;
249 default:
250 break;
252 free(p);
255 if (!opt->extended)
256 return;
257 free_pattern_expr(opt->pattern_expression);
260 static char *end_of_line(char *cp, unsigned long *left)
262 unsigned long l = *left;
263 while (l && *cp != '\n') {
264 l--;
265 cp++;
267 *left = l;
268 return cp;
271 static int word_char(char ch)
273 return isalnum(ch) || ch == '_';
276 static void show_name(struct grep_opt *opt, const char *name)
278 opt->output(opt, name, strlen(name));
279 opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
283 static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t *match)
285 char *hit;
286 if (ignore_case)
287 hit = strcasestr(line, pattern);
288 else
289 hit = strstr(line, pattern);
291 if (!hit) {
292 match->rm_so = match->rm_eo = -1;
293 return REG_NOMATCH;
295 else {
296 match->rm_so = hit - line;
297 match->rm_eo = match->rm_so + strlen(pattern);
298 return 0;
302 static int strip_timestamp(char *bol, char **eol_p)
304 char *eol = *eol_p;
305 int ch;
307 while (bol < --eol) {
308 if (*eol != '>')
309 continue;
310 *eol_p = ++eol;
311 ch = *eol;
312 *eol = '\0';
313 return ch;
315 return 0;
318 static struct {
319 const char *field;
320 size_t len;
321 } header_field[] = {
322 { "author ", 7 },
323 { "committer ", 10 },
326 static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
327 enum grep_context ctx,
328 regmatch_t *pmatch, int eflags)
330 int hit = 0;
331 int saved_ch = 0;
332 const char *start = bol;
334 if ((p->token != GREP_PATTERN) &&
335 ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
336 return 0;
338 if (p->token == GREP_PATTERN_HEAD) {
339 const char *field;
340 size_t len;
341 assert(p->field < ARRAY_SIZE(header_field));
342 field = header_field[p->field].field;
343 len = header_field[p->field].len;
344 if (strncmp(bol, field, len))
345 return 0;
346 bol += len;
347 saved_ch = strip_timestamp(bol, &eol);
350 again:
351 if (p->fixed)
352 hit = !fixmatch(p->pattern, bol, p->ignore_case, pmatch);
353 else
354 hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
356 if (hit && p->word_regexp) {
357 if ((pmatch[0].rm_so < 0) ||
358 (eol - bol) < pmatch[0].rm_so ||
359 (pmatch[0].rm_eo < 0) ||
360 (eol - bol) < pmatch[0].rm_eo)
361 die("regexp returned nonsense");
363 /* Match beginning must be either beginning of the
364 * line, or at word boundary (i.e. the last char must
365 * not be a word char). Similarly, match end must be
366 * either end of the line, or at word boundary
367 * (i.e. the next char must not be a word char).
369 if ( ((pmatch[0].rm_so == 0) ||
370 !word_char(bol[pmatch[0].rm_so-1])) &&
371 ((pmatch[0].rm_eo == (eol-bol)) ||
372 !word_char(bol[pmatch[0].rm_eo])) )
374 else
375 hit = 0;
377 /* Words consist of at least one character. */
378 if (pmatch->rm_so == pmatch->rm_eo)
379 hit = 0;
381 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
382 /* There could be more than one match on the
383 * line, and the first match might not be
384 * strict word match. But later ones could be!
385 * Forward to the next possible start, i.e. the
386 * next position following a non-word char.
388 bol = pmatch[0].rm_so + bol + 1;
389 while (word_char(bol[-1]) && bol < eol)
390 bol++;
391 eflags |= REG_NOTBOL;
392 if (bol < eol)
393 goto again;
396 if (p->token == GREP_PATTERN_HEAD && saved_ch)
397 *eol = saved_ch;
398 if (hit) {
399 pmatch[0].rm_so += bol - start;
400 pmatch[0].rm_eo += bol - start;
402 return hit;
405 static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
406 enum grep_context ctx, int collect_hits)
408 int h = 0;
409 regmatch_t match;
411 if (!x)
412 die("Not a valid grep expression");
413 switch (x->node) {
414 case GREP_NODE_ATOM:
415 h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
416 break;
417 case GREP_NODE_NOT:
418 h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
419 break;
420 case GREP_NODE_AND:
421 if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
422 return 0;
423 h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
424 break;
425 case GREP_NODE_OR:
426 if (!collect_hits)
427 return (match_expr_eval(x->u.binary.left,
428 bol, eol, ctx, 0) ||
429 match_expr_eval(x->u.binary.right,
430 bol, eol, ctx, 0));
431 h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
432 x->u.binary.left->hit |= h;
433 h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
434 break;
435 default:
436 die("Unexpected node type (internal error) %d", x->node);
438 if (collect_hits)
439 x->hit |= h;
440 return h;
443 static int match_expr(struct grep_opt *opt, char *bol, char *eol,
444 enum grep_context ctx, int collect_hits)
446 struct grep_expr *x = opt->pattern_expression;
447 return match_expr_eval(x, bol, eol, ctx, collect_hits);
450 static int match_line(struct grep_opt *opt, char *bol, char *eol,
451 enum grep_context ctx, int collect_hits)
453 struct grep_pat *p;
454 regmatch_t match;
456 if (opt->extended)
457 return match_expr(opt, bol, eol, ctx, collect_hits);
459 /* we do not call with collect_hits without being extended */
460 for (p = opt->pattern_list; p; p = p->next) {
461 if (match_one_pattern(p, bol, eol, ctx, &match, 0))
462 return 1;
464 return 0;
467 static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
468 enum grep_context ctx,
469 regmatch_t *pmatch, int eflags)
471 regmatch_t match;
473 if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
474 return 0;
475 if (match.rm_so < 0 || match.rm_eo < 0)
476 return 0;
477 if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
478 if (match.rm_so > pmatch->rm_so)
479 return 1;
480 if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
481 return 1;
483 pmatch->rm_so = match.rm_so;
484 pmatch->rm_eo = match.rm_eo;
485 return 1;
488 static int next_match(struct grep_opt *opt, char *bol, char *eol,
489 enum grep_context ctx, regmatch_t *pmatch, int eflags)
491 struct grep_pat *p;
492 int hit = 0;
494 pmatch->rm_so = pmatch->rm_eo = -1;
495 if (bol < eol) {
496 for (p = opt->pattern_list; p; p = p->next) {
497 switch (p->token) {
498 case GREP_PATTERN: /* atom */
499 case GREP_PATTERN_HEAD:
500 case GREP_PATTERN_BODY:
501 hit |= match_next_pattern(p, bol, eol, ctx,
502 pmatch, eflags);
503 break;
504 default:
505 break;
509 return hit;
512 static void show_line(struct grep_opt *opt, char *bol, char *eol,
513 const char *name, unsigned lno, char sign)
515 int rest = eol - bol;
516 char sign_str[1];
518 sign_str[0] = sign;
519 if (opt->pre_context || opt->post_context) {
520 if (opt->last_shown == 0) {
521 if (opt->show_hunk_mark)
522 opt->output(opt, "--\n", 3);
523 else
524 opt->show_hunk_mark = 1;
525 } else if (lno > opt->last_shown + 1)
526 opt->output(opt, "--\n", 3);
528 opt->last_shown = lno;
530 if (opt->null_following_name)
531 sign_str[0] = '\0';
532 if (opt->pathname) {
533 opt->output(opt, name, strlen(name));
534 opt->output(opt, sign_str, 1);
536 if (opt->linenum) {
537 char buf[32];
538 snprintf(buf, sizeof(buf), "%d", lno);
539 opt->output(opt, buf, strlen(buf));
540 opt->output(opt, sign_str, 1);
542 if (opt->color) {
543 regmatch_t match;
544 enum grep_context ctx = GREP_CONTEXT_BODY;
545 int ch = *eol;
546 int eflags = 0;
548 *eol = '\0';
549 while (next_match(opt, bol, eol, ctx, &match, eflags)) {
550 if (match.rm_so == match.rm_eo)
551 break;
553 opt->output(opt, bol, match.rm_so);
554 opt->output(opt, opt->color_match,
555 strlen(opt->color_match));
556 opt->output(opt, bol + match.rm_so,
557 (int)(match.rm_eo - match.rm_so));
558 opt->output(opt, GIT_COLOR_RESET,
559 strlen(GIT_COLOR_RESET));
560 bol += match.rm_eo;
561 rest -= match.rm_eo;
562 eflags = REG_NOTBOL;
564 *eol = ch;
566 opt->output(opt, bol, rest);
567 opt->output(opt, "\n", 1);
570 static int match_funcname(struct grep_opt *opt, char *bol, char *eol)
572 xdemitconf_t *xecfg = opt->priv;
573 if (xecfg && xecfg->find_func) {
574 char buf[1];
575 return xecfg->find_func(bol, eol - bol, buf, 1,
576 xecfg->find_func_priv) >= 0;
579 if (bol == eol)
580 return 0;
581 if (isalpha(*bol) || *bol == '_' || *bol == '$')
582 return 1;
583 return 0;
586 static void show_funcname_line(struct grep_opt *opt, const char *name,
587 char *buf, char *bol, unsigned lno)
589 while (bol > buf) {
590 char *eol = --bol;
592 while (bol > buf && bol[-1] != '\n')
593 bol--;
594 lno--;
596 if (lno <= opt->last_shown)
597 break;
599 if (match_funcname(opt, bol, eol)) {
600 show_line(opt, bol, eol, name, lno, '=');
601 break;
606 static void show_pre_context(struct grep_opt *opt, const char *name, char *buf,
607 char *bol, unsigned lno)
609 unsigned cur = lno, from = 1, funcname_lno = 0;
610 int funcname_needed = opt->funcname;
612 if (opt->pre_context < lno)
613 from = lno - opt->pre_context;
614 if (from <= opt->last_shown)
615 from = opt->last_shown + 1;
617 /* Rewind. */
618 while (bol > buf && cur > from) {
619 char *eol = --bol;
621 while (bol > buf && bol[-1] != '\n')
622 bol--;
623 cur--;
624 if (funcname_needed && match_funcname(opt, bol, eol)) {
625 funcname_lno = cur;
626 funcname_needed = 0;
630 /* We need to look even further back to find a function signature. */
631 if (opt->funcname && funcname_needed)
632 show_funcname_line(opt, name, buf, bol, cur);
634 /* Back forward. */
635 while (cur < lno) {
636 char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
638 while (*eol != '\n')
639 eol++;
640 show_line(opt, bol, eol, name, cur, sign);
641 bol = eol + 1;
642 cur++;
646 static int should_lookahead(struct grep_opt *opt)
648 struct grep_pat *p;
650 if (opt->extended)
651 return 0; /* punt for too complex stuff */
652 if (opt->invert)
653 return 0;
654 for (p = opt->pattern_list; p; p = p->next) {
655 if (p->token != GREP_PATTERN)
656 return 0; /* punt for "header only" and stuff */
658 return 1;
661 static int look_ahead(struct grep_opt *opt,
662 unsigned long *left_p,
663 unsigned *lno_p,
664 char **bol_p)
666 unsigned lno = *lno_p;
667 char *bol = *bol_p;
668 struct grep_pat *p;
669 char *sp, *last_bol;
670 regoff_t earliest = -1;
672 for (p = opt->pattern_list; p; p = p->next) {
673 int hit;
674 regmatch_t m;
676 if (p->fixed)
677 hit = !fixmatch(p->pattern, bol, p->ignore_case, &m);
678 else {
679 #ifdef REG_STARTEND
680 m.rm_so = 0;
681 m.rm_eo = *left_p;
682 hit = !regexec(&p->regexp, bol, 1, &m, REG_STARTEND);
683 #else
684 hit = !regexec(&p->regexp, bol, 1, &m, 0);
685 #endif
687 if (!hit || m.rm_so < 0 || m.rm_eo < 0)
688 continue;
689 if (earliest < 0 || m.rm_so < earliest)
690 earliest = m.rm_so;
693 if (earliest < 0) {
694 *bol_p = bol + *left_p;
695 *left_p = 0;
696 return 1;
698 for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
699 ; /* find the beginning of the line */
700 last_bol = sp;
702 for (sp = bol; sp < last_bol; sp++) {
703 if (*sp == '\n')
704 lno++;
706 *left_p -= last_bol - bol;
707 *bol_p = last_bol;
708 *lno_p = lno;
709 return 0;
712 int grep_threads_ok(const struct grep_opt *opt)
714 /* If this condition is true, then we may use the attribute
715 * machinery in grep_buffer_1. The attribute code is not
716 * thread safe, so we disable the use of threads.
718 if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
719 !opt->name_only)
720 return 0;
722 /* If we are showing hunk marks, we should not do it for the
723 * first match. The synchronization problem we get for this
724 * constraint is not yet solved, so we disable threading in
725 * this case.
727 if (opt->pre_context || opt->post_context)
728 return 0;
730 return 1;
733 static void std_output(struct grep_opt *opt, const void *buf, size_t size)
735 fwrite(buf, size, 1, stdout);
738 static int grep_buffer_1(struct grep_opt *opt, const char *name,
739 char *buf, unsigned long size, int collect_hits)
741 char *bol = buf;
742 unsigned long left = size;
743 unsigned lno = 1;
744 unsigned last_hit = 0;
745 int binary_match_only = 0;
746 unsigned count = 0;
747 int try_lookahead = 0;
748 enum grep_context ctx = GREP_CONTEXT_HEAD;
749 xdemitconf_t xecfg;
751 opt->last_shown = 0;
753 if (!opt->output)
754 opt->output = std_output;
756 if (buffer_is_binary(buf, size)) {
757 switch (opt->binary) {
758 case GREP_BINARY_DEFAULT:
759 binary_match_only = 1;
760 break;
761 case GREP_BINARY_NOMATCH:
762 return 0; /* Assume unmatch */
763 break;
764 default:
765 break;
769 memset(&xecfg, 0, sizeof(xecfg));
770 if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
771 !opt->name_only && !binary_match_only && !collect_hits) {
772 struct userdiff_driver *drv = userdiff_find_by_path(name);
773 if (drv && drv->funcname.pattern) {
774 const struct userdiff_funcname *pe = &drv->funcname;
775 xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
776 opt->priv = &xecfg;
779 try_lookahead = should_lookahead(opt);
781 while (left) {
782 char *eol, ch;
783 int hit;
786 * look_ahead() skips quicly to the line that possibly
787 * has the next hit; don't call it if we need to do
788 * something more than just skipping the current line
789 * in response to an unmatch for the current line. E.g.
790 * inside a post-context window, we will show the current
791 * line as a context around the previous hit when it
792 * doesn't hit.
794 if (try_lookahead
795 && !(last_hit
796 && lno <= last_hit + opt->post_context)
797 && look_ahead(opt, &left, &lno, &bol))
798 break;
799 eol = end_of_line(bol, &left);
800 ch = *eol;
801 *eol = 0;
803 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
804 ctx = GREP_CONTEXT_BODY;
806 hit = match_line(opt, bol, eol, ctx, collect_hits);
807 *eol = ch;
809 if (collect_hits)
810 goto next_line;
812 /* "grep -v -e foo -e bla" should list lines
813 * that do not have either, so inversion should
814 * be done outside.
816 if (opt->invert)
817 hit = !hit;
818 if (opt->unmatch_name_only) {
819 if (hit)
820 return 0;
821 goto next_line;
823 if (hit) {
824 count++;
825 if (opt->status_only)
826 return 1;
827 if (binary_match_only) {
828 opt->output(opt, "Binary file ", 12);
829 opt->output(opt, name, strlen(name));
830 opt->output(opt, " matches\n", 9);
831 return 1;
833 if (opt->name_only) {
834 show_name(opt, name);
835 return 1;
837 /* Hit at this line. If we haven't shown the
838 * pre-context lines, we would need to show them.
839 * When asked to do "count", this still show
840 * the context which is nonsense, but the user
841 * deserves to get that ;-).
843 if (opt->pre_context)
844 show_pre_context(opt, name, buf, bol, lno);
845 else if (opt->funcname)
846 show_funcname_line(opt, name, buf, bol, lno);
847 if (!opt->count)
848 show_line(opt, bol, eol, name, lno, ':');
849 last_hit = lno;
851 else if (last_hit &&
852 lno <= last_hit + opt->post_context) {
853 /* If the last hit is within the post context,
854 * we need to show this line.
856 show_line(opt, bol, eol, name, lno, '-');
859 next_line:
860 bol = eol + 1;
861 if (!left)
862 break;
863 left--;
864 lno++;
867 if (collect_hits)
868 return 0;
870 if (opt->status_only)
871 return 0;
872 if (opt->unmatch_name_only) {
873 /* We did not see any hit, so we want to show this */
874 show_name(opt, name);
875 return 1;
878 xdiff_clear_find_func(&xecfg);
879 opt->priv = NULL;
881 /* NEEDSWORK:
882 * The real "grep -c foo *.c" gives many "bar.c:0" lines,
883 * which feels mostly useless but sometimes useful. Maybe
884 * make it another option? For now suppress them.
886 if (opt->count && count) {
887 char buf[32];
888 opt->output(opt, name, strlen(name));
889 snprintf(buf, sizeof(buf), "%c%u\n",
890 opt->null_following_name ? '\0' : ':', count);
891 opt->output(opt, buf, strlen(buf));
893 return !!last_hit;
896 static void clr_hit_marker(struct grep_expr *x)
898 /* All-hit markers are meaningful only at the very top level
899 * OR node.
901 while (1) {
902 x->hit = 0;
903 if (x->node != GREP_NODE_OR)
904 return;
905 x->u.binary.left->hit = 0;
906 x = x->u.binary.right;
910 static int chk_hit_marker(struct grep_expr *x)
912 /* Top level nodes have hit markers. See if they all are hits */
913 while (1) {
914 if (x->node != GREP_NODE_OR)
915 return x->hit;
916 if (!x->u.binary.left->hit)
917 return 0;
918 x = x->u.binary.right;
922 int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
925 * we do not have to do the two-pass grep when we do not check
926 * buffer-wide "all-match".
928 if (!opt->all_match)
929 return grep_buffer_1(opt, name, buf, size, 0);
931 /* Otherwise the toplevel "or" terms hit a bit differently.
932 * We first clear hit markers from them.
934 clr_hit_marker(opt->pattern_expression);
935 grep_buffer_1(opt, name, buf, size, 1);
937 if (!chk_hit_marker(opt->pattern_expression))
938 return 0;
940 return grep_buffer_1(opt, name, buf, size, 0);