Merge branch 'jc/apply-include-exclude'
[git.git] / grep.c
blob706351197fc26efa10c4666d38433f8fbdf1d6b5
1 #include "cache.h"
2 #include "grep.h"
3 #include "xdiff-interface.h"
5 void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field field, const char *pat)
7 struct grep_pat *p = xcalloc(1, sizeof(*p));
8 p->pattern = pat;
9 p->origin = "header";
10 p->no = 0;
11 p->token = GREP_PATTERN_HEAD;
12 p->field = field;
13 *opt->pattern_tail = p;
14 opt->pattern_tail = &p->next;
15 p->next = NULL;
18 void append_grep_pattern(struct grep_opt *opt, const char *pat,
19 const char *origin, int no, enum grep_pat_token t)
21 struct grep_pat *p = xcalloc(1, sizeof(*p));
22 p->pattern = pat;
23 p->origin = origin;
24 p->no = no;
25 p->token = t;
26 *opt->pattern_tail = p;
27 opt->pattern_tail = &p->next;
28 p->next = NULL;
31 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
33 int err = regcomp(&p->regexp, p->pattern, opt->regflags);
34 if (err) {
35 char errbuf[1024];
36 char where[1024];
37 if (p->no)
38 sprintf(where, "In '%s' at %d, ",
39 p->origin, p->no);
40 else if (p->origin)
41 sprintf(where, "%s, ", p->origin);
42 else
43 where[0] = 0;
44 regerror(err, &p->regexp, errbuf, 1024);
45 regfree(&p->regexp);
46 die("%s'%s': %s", where, p->pattern, errbuf);
50 static struct grep_expr *compile_pattern_or(struct grep_pat **);
51 static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
53 struct grep_pat *p;
54 struct grep_expr *x;
56 p = *list;
57 switch (p->token) {
58 case GREP_PATTERN: /* atom */
59 case GREP_PATTERN_HEAD:
60 case GREP_PATTERN_BODY:
61 x = xcalloc(1, sizeof (struct grep_expr));
62 x->node = GREP_NODE_ATOM;
63 x->u.atom = p;
64 *list = p->next;
65 return x;
66 case GREP_OPEN_PAREN:
67 *list = p->next;
68 x = compile_pattern_or(list);
69 if (!x)
70 return NULL;
71 if (!*list || (*list)->token != GREP_CLOSE_PAREN)
72 die("unmatched parenthesis");
73 *list = (*list)->next;
74 return x;
75 default:
76 return NULL;
80 static struct grep_expr *compile_pattern_not(struct grep_pat **list)
82 struct grep_pat *p;
83 struct grep_expr *x;
85 p = *list;
86 switch (p->token) {
87 case GREP_NOT:
88 if (!p->next)
89 die("--not not followed by pattern expression");
90 *list = p->next;
91 x = xcalloc(1, sizeof (struct grep_expr));
92 x->node = GREP_NODE_NOT;
93 x->u.unary = compile_pattern_not(list);
94 if (!x->u.unary)
95 die("--not followed by non pattern expression");
96 return x;
97 default:
98 return compile_pattern_atom(list);
102 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
104 struct grep_pat *p;
105 struct grep_expr *x, *y, *z;
107 x = compile_pattern_not(list);
108 p = *list;
109 if (p && p->token == GREP_AND) {
110 if (!p->next)
111 die("--and not followed by pattern expression");
112 *list = p->next;
113 y = compile_pattern_and(list);
114 if (!y)
115 die("--and not followed by pattern expression");
116 z = xcalloc(1, sizeof (struct grep_expr));
117 z->node = GREP_NODE_AND;
118 z->u.binary.left = x;
119 z->u.binary.right = y;
120 return z;
122 return x;
125 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
127 struct grep_pat *p;
128 struct grep_expr *x, *y, *z;
130 x = compile_pattern_and(list);
131 p = *list;
132 if (x && p && p->token != GREP_CLOSE_PAREN) {
133 y = compile_pattern_or(list);
134 if (!y)
135 die("not a pattern expression %s", p->pattern);
136 z = xcalloc(1, sizeof (struct grep_expr));
137 z->node = GREP_NODE_OR;
138 z->u.binary.left = x;
139 z->u.binary.right = y;
140 return z;
142 return x;
145 static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
147 return compile_pattern_or(list);
150 void compile_grep_patterns(struct grep_opt *opt)
152 struct grep_pat *p;
154 if (opt->all_match)
155 opt->extended = 1;
157 for (p = opt->pattern_list; p; p = p->next) {
158 switch (p->token) {
159 case GREP_PATTERN: /* atom */
160 case GREP_PATTERN_HEAD:
161 case GREP_PATTERN_BODY:
162 if (!opt->fixed)
163 compile_regexp(p, opt);
164 break;
165 default:
166 opt->extended = 1;
167 break;
171 if (!opt->extended)
172 return;
174 /* Then bundle them up in an expression.
175 * A classic recursive descent parser would do.
177 p = opt->pattern_list;
178 opt->pattern_expression = compile_pattern_expr(&p);
179 if (p)
180 die("incomplete pattern expression: %s", p->pattern);
183 static void free_pattern_expr(struct grep_expr *x)
185 switch (x->node) {
186 case GREP_NODE_ATOM:
187 break;
188 case GREP_NODE_NOT:
189 free_pattern_expr(x->u.unary);
190 break;
191 case GREP_NODE_AND:
192 case GREP_NODE_OR:
193 free_pattern_expr(x->u.binary.left);
194 free_pattern_expr(x->u.binary.right);
195 break;
197 free(x);
200 void free_grep_patterns(struct grep_opt *opt)
202 struct grep_pat *p, *n;
204 for (p = opt->pattern_list; p; p = n) {
205 n = p->next;
206 switch (p->token) {
207 case GREP_PATTERN: /* atom */
208 case GREP_PATTERN_HEAD:
209 case GREP_PATTERN_BODY:
210 regfree(&p->regexp);
211 break;
212 default:
213 break;
215 free(p);
218 if (!opt->extended)
219 return;
220 free_pattern_expr(opt->pattern_expression);
223 static char *end_of_line(char *cp, unsigned long *left)
225 unsigned long l = *left;
226 while (l && *cp != '\n') {
227 l--;
228 cp++;
230 *left = l;
231 return cp;
234 static int word_char(char ch)
236 return isalnum(ch) || ch == '_';
239 static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
240 const char *name, unsigned lno, char sign)
242 if (opt->pathname)
243 printf("%s%c", name, sign);
244 if (opt->linenum)
245 printf("%d%c", lno, sign);
246 printf("%.*s\n", (int)(eol-bol), bol);
249 static int fixmatch(const char *pattern, char *line, regmatch_t *match)
251 char *hit = strstr(line, pattern);
252 if (!hit) {
253 match->rm_so = match->rm_eo = -1;
254 return REG_NOMATCH;
256 else {
257 match->rm_so = hit - line;
258 match->rm_eo = match->rm_so + strlen(pattern);
259 return 0;
263 static int strip_timestamp(char *bol, char **eol_p)
265 char *eol = *eol_p;
266 int ch;
268 while (bol < --eol) {
269 if (*eol != '>')
270 continue;
271 *eol_p = ++eol;
272 ch = *eol;
273 *eol = '\0';
274 return ch;
276 return 0;
279 static struct {
280 const char *field;
281 size_t len;
282 } header_field[] = {
283 { "author ", 7 },
284 { "committer ", 10 },
287 static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
289 int hit = 0;
290 int at_true_bol = 1;
291 int saved_ch = 0;
292 regmatch_t pmatch[10];
294 if ((p->token != GREP_PATTERN) &&
295 ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
296 return 0;
298 if (p->token == GREP_PATTERN_HEAD) {
299 const char *field;
300 size_t len;
301 assert(p->field < ARRAY_SIZE(header_field));
302 field = header_field[p->field].field;
303 len = header_field[p->field].len;
304 if (strncmp(bol, field, len))
305 return 0;
306 bol += len;
307 saved_ch = strip_timestamp(bol, &eol);
310 again:
311 if (!opt->fixed) {
312 regex_t *exp = &p->regexp;
313 hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
314 pmatch, 0);
316 else {
317 hit = !fixmatch(p->pattern, bol, pmatch);
320 if (hit && opt->word_regexp) {
321 if ((pmatch[0].rm_so < 0) ||
322 (eol - bol) <= pmatch[0].rm_so ||
323 (pmatch[0].rm_eo < 0) ||
324 (eol - bol) < pmatch[0].rm_eo)
325 die("regexp returned nonsense");
327 /* Match beginning must be either beginning of the
328 * line, or at word boundary (i.e. the last char must
329 * not be a word char). Similarly, match end must be
330 * either end of the line, or at word boundary
331 * (i.e. the next char must not be a word char).
333 if ( ((pmatch[0].rm_so == 0 && at_true_bol) ||
334 !word_char(bol[pmatch[0].rm_so-1])) &&
335 ((pmatch[0].rm_eo == (eol-bol)) ||
336 !word_char(bol[pmatch[0].rm_eo])) )
338 else
339 hit = 0;
341 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
342 /* There could be more than one match on the
343 * line, and the first match might not be
344 * strict word match. But later ones could be!
346 bol = pmatch[0].rm_so + bol + 1;
347 at_true_bol = 0;
348 goto again;
351 if (p->token == GREP_PATTERN_HEAD && saved_ch)
352 *eol = saved_ch;
353 return hit;
356 static int match_expr_eval(struct grep_opt *o,
357 struct grep_expr *x,
358 char *bol, char *eol,
359 enum grep_context ctx,
360 int collect_hits)
362 int h = 0;
364 switch (x->node) {
365 case GREP_NODE_ATOM:
366 h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
367 break;
368 case GREP_NODE_NOT:
369 h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
370 break;
371 case GREP_NODE_AND:
372 if (!collect_hits)
373 return (match_expr_eval(o, x->u.binary.left,
374 bol, eol, ctx, 0) &&
375 match_expr_eval(o, x->u.binary.right,
376 bol, eol, ctx, 0));
377 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
378 h &= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 0);
379 break;
380 case GREP_NODE_OR:
381 if (!collect_hits)
382 return (match_expr_eval(o, x->u.binary.left,
383 bol, eol, ctx, 0) ||
384 match_expr_eval(o, x->u.binary.right,
385 bol, eol, ctx, 0));
386 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
387 x->u.binary.left->hit |= h;
388 h |= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 1);
389 break;
390 default:
391 die("Unexpected node type (internal error) %d\n", x->node);
393 if (collect_hits)
394 x->hit |= h;
395 return h;
398 static int match_expr(struct grep_opt *opt, char *bol, char *eol,
399 enum grep_context ctx, int collect_hits)
401 struct grep_expr *x = opt->pattern_expression;
402 return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
405 static int match_line(struct grep_opt *opt, char *bol, char *eol,
406 enum grep_context ctx, int collect_hits)
408 struct grep_pat *p;
409 if (opt->extended)
410 return match_expr(opt, bol, eol, ctx, collect_hits);
412 /* we do not call with collect_hits without being extended */
413 for (p = opt->pattern_list; p; p = p->next) {
414 if (match_one_pattern(opt, p, bol, eol, ctx))
415 return 1;
417 return 0;
420 static int grep_buffer_1(struct grep_opt *opt, const char *name,
421 char *buf, unsigned long size, int collect_hits)
423 char *bol = buf;
424 unsigned long left = size;
425 unsigned lno = 1;
426 struct pre_context_line {
427 char *bol;
428 char *eol;
429 } *prev = NULL, *pcl;
430 unsigned last_hit = 0;
431 unsigned last_shown = 0;
432 int binary_match_only = 0;
433 const char *hunk_mark = "";
434 unsigned count = 0;
435 enum grep_context ctx = GREP_CONTEXT_HEAD;
437 if (buffer_is_binary(buf, size)) {
438 switch (opt->binary) {
439 case GREP_BINARY_DEFAULT:
440 binary_match_only = 1;
441 break;
442 case GREP_BINARY_NOMATCH:
443 return 0; /* Assume unmatch */
444 break;
445 default:
446 break;
450 if (opt->pre_context)
451 prev = xcalloc(opt->pre_context, sizeof(*prev));
452 if (opt->pre_context || opt->post_context)
453 hunk_mark = "--\n";
455 while (left) {
456 char *eol, ch;
457 int hit;
459 eol = end_of_line(bol, &left);
460 ch = *eol;
461 *eol = 0;
463 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
464 ctx = GREP_CONTEXT_BODY;
466 hit = match_line(opt, bol, eol, ctx, collect_hits);
467 *eol = ch;
469 if (collect_hits)
470 goto next_line;
472 /* "grep -v -e foo -e bla" should list lines
473 * that do not have either, so inversion should
474 * be done outside.
476 if (opt->invert)
477 hit = !hit;
478 if (opt->unmatch_name_only) {
479 if (hit)
480 return 0;
481 goto next_line;
483 if (hit) {
484 count++;
485 if (opt->status_only)
486 return 1;
487 if (binary_match_only) {
488 printf("Binary file %s matches\n", name);
489 return 1;
491 if (opt->name_only) {
492 printf("%s\n", name);
493 return 1;
495 /* Hit at this line. If we haven't shown the
496 * pre-context lines, we would need to show them.
497 * When asked to do "count", this still show
498 * the context which is nonsense, but the user
499 * deserves to get that ;-).
501 if (opt->pre_context) {
502 unsigned from;
503 if (opt->pre_context < lno)
504 from = lno - opt->pre_context;
505 else
506 from = 1;
507 if (from <= last_shown)
508 from = last_shown + 1;
509 if (last_shown && from != last_shown + 1)
510 printf(hunk_mark);
511 while (from < lno) {
512 pcl = &prev[lno-from-1];
513 show_line(opt, pcl->bol, pcl->eol,
514 name, from, '-');
515 from++;
517 last_shown = lno-1;
519 if (last_shown && lno != last_shown + 1)
520 printf(hunk_mark);
521 if (!opt->count)
522 show_line(opt, bol, eol, name, lno, ':');
523 last_shown = last_hit = lno;
525 else if (last_hit &&
526 lno <= last_hit + opt->post_context) {
527 /* If the last hit is within the post context,
528 * we need to show this line.
530 if (last_shown && lno != last_shown + 1)
531 printf(hunk_mark);
532 show_line(opt, bol, eol, name, lno, '-');
533 last_shown = lno;
535 if (opt->pre_context) {
536 memmove(prev+1, prev,
537 (opt->pre_context-1) * sizeof(*prev));
538 prev->bol = bol;
539 prev->eol = eol;
542 next_line:
543 bol = eol + 1;
544 if (!left)
545 break;
546 left--;
547 lno++;
550 free(prev);
551 if (collect_hits)
552 return 0;
554 if (opt->status_only)
555 return 0;
556 if (opt->unmatch_name_only) {
557 /* We did not see any hit, so we want to show this */
558 printf("%s\n", name);
559 return 1;
562 /* NEEDSWORK:
563 * The real "grep -c foo *.c" gives many "bar.c:0" lines,
564 * which feels mostly useless but sometimes useful. Maybe
565 * make it another option? For now suppress them.
567 if (opt->count && count)
568 printf("%s:%u\n", name, count);
569 return !!last_hit;
572 static void clr_hit_marker(struct grep_expr *x)
574 /* All-hit markers are meaningful only at the very top level
575 * OR node.
577 while (1) {
578 x->hit = 0;
579 if (x->node != GREP_NODE_OR)
580 return;
581 x->u.binary.left->hit = 0;
582 x = x->u.binary.right;
586 static int chk_hit_marker(struct grep_expr *x)
588 /* Top level nodes have hit markers. See if they all are hits */
589 while (1) {
590 if (x->node != GREP_NODE_OR)
591 return x->hit;
592 if (!x->u.binary.left->hit)
593 return 0;
594 x = x->u.binary.right;
598 int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
601 * we do not have to do the two-pass grep when we do not check
602 * buffer-wide "all-match".
604 if (!opt->all_match)
605 return grep_buffer_1(opt, name, buf, size, 0);
607 /* Otherwise the toplevel "or" terms hit a bit differently.
608 * We first clear hit markers from them.
610 clr_hit_marker(opt->pattern_expression);
611 grep_buffer_1(opt, name, buf, size, 1);
613 if (!chk_hit_marker(opt->pattern_expression))
614 return 0;
616 return grep_buffer_1(opt, name, buf, size, 0);