Move buffer_is_binary() to xdiff-interface.h
[git/git.git] / grep.c
CommitLineData
83b5d2f5 1#include "cache.h"
83b5d2f5 2#include "grep.h"
6bfce93e 3#include "xdiff-interface.h"
83b5d2f5
JH
4
5void 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}
17
18static 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}
36
0ab7befa 37static struct grep_expr *compile_pattern_or(struct grep_pat **);
83b5d2f5
JH
38static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
39{
40 struct grep_pat *p;
41 struct grep_expr *x;
42
43 p = *list;
44 switch (p->token) {
45 case GREP_PATTERN: /* atom */
480c1ca6
JH
46 case GREP_PATTERN_HEAD:
47 case GREP_PATTERN_BODY:
83b5d2f5
JH
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;
0ab7befa 55 x = compile_pattern_or(list);
83b5d2f5
JH
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}
66
67static struct grep_expr *compile_pattern_not(struct grep_pat **list)
68{
69 struct grep_pat *p;
70 struct grep_expr *x;
71
72 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}
88
89static struct grep_expr *compile_pattern_and(struct grep_pat **list)
90{
91 struct grep_pat *p;
92 struct grep_expr *x, *y, *z;
93
94 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}
111
112static struct grep_expr *compile_pattern_or(struct grep_pat **list)
113{
114 struct grep_pat *p;
115 struct grep_expr *x, *y, *z;
116
117 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}
131
132static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
133{
134 return compile_pattern_or(list);
135}
136
137void compile_grep_patterns(struct grep_opt *opt)
138{
139 struct grep_pat *p;
140
0ab7befa
JH
141 if (opt->all_match)
142 opt->extended = 1;
143
83b5d2f5 144 for (p = opt->pattern_list; p; p = p->next) {
480c1ca6
JH
145 switch (p->token) {
146 case GREP_PATTERN: /* atom */
147 case GREP_PATTERN_HEAD:
148 case GREP_PATTERN_BODY:
a3f5d02e
JH
149 if (!opt->fixed)
150 compile_regexp(p, opt);
480c1ca6
JH
151 break;
152 default:
83b5d2f5 153 opt->extended = 1;
480c1ca6
JH
154 break;
155 }
83b5d2f5
JH
156 }
157
158 if (!opt->extended)
159 return;
160
161 /* 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}
169
b48fb5b6
JH
170static 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}
186
187void free_grep_patterns(struct grep_opt *opt)
188{
189 struct grep_pat *p, *n;
190
191 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
205 if (!opt->extended)
206 return;
207 free_pattern_expr(opt->pattern_expression);
208}
209
83b5d2f5
JH
210static 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}
220
221static int word_char(char ch)
222{
223 return isalnum(ch) || ch == '_';
224}
225
226static 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
83b5d2f5
JH
236static int fixmatch(const char *pattern, char *line, regmatch_t *match)
237{
238 char *hit = strstr(line, pattern);
239 if (!hit) {
240 match->rm_so = match->rm_eo = -1;
241 return REG_NOMATCH;
242 }
243 else {
244 match->rm_so = hit - line;
245 match->rm_eo = match->rm_so + strlen(pattern);
246 return 0;
247 }
248}
249
480c1ca6 250static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
83b5d2f5
JH
251{
252 int hit = 0;
253 int at_true_bol = 1;
254 regmatch_t pmatch[10];
255
480c1ca6
JH
256 if ((p->token != GREP_PATTERN) &&
257 ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
258 return 0;
259
83b5d2f5
JH
260 again:
261 if (!opt->fixed) {
262 regex_t *exp = &p->regexp;
263 hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
264 pmatch, 0);
265 }
266 else {
267 hit = !fixmatch(p->pattern, bol, pmatch);
268 }
269
270 if (hit && opt->word_regexp) {
271 if ((pmatch[0].rm_so < 0) ||
272 (eol - bol) <= pmatch[0].rm_so ||
273 (pmatch[0].rm_eo < 0) ||
274 (eol - bol) < pmatch[0].rm_eo)
275 die("regexp returned nonsense");
276
277 /* Match beginning must be either beginning of the
278 * line, or at word boundary (i.e. the last char must
279 * not be a word char). Similarly, match end must be
280 * either end of the line, or at word boundary
281 * (i.e. the next char must not be a word char).
282 */
283 if ( ((pmatch[0].rm_so == 0 && at_true_bol) ||
284 !word_char(bol[pmatch[0].rm_so-1])) &&
285 ((pmatch[0].rm_eo == (eol-bol)) ||
286 !word_char(bol[pmatch[0].rm_eo])) )
287 ;
288 else
289 hit = 0;
290
291 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
292 /* There could be more than one match on the
293 * line, and the first match might not be
294 * strict word match. But later ones could be!
295 */
296 bol = pmatch[0].rm_so + bol + 1;
297 at_true_bol = 0;
298 goto again;
299 }
300 }
301 return hit;
302}
303
0ab7befa 304static int match_expr_eval(struct grep_opt *o,
83b5d2f5 305 struct grep_expr *x,
480c1ca6 306 char *bol, char *eol,
0ab7befa
JH
307 enum grep_context ctx,
308 int collect_hits)
83b5d2f5 309{
0ab7befa
JH
310 int h = 0;
311
83b5d2f5
JH
312 switch (x->node) {
313 case GREP_NODE_ATOM:
0ab7befa 314 h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
83b5d2f5
JH
315 break;
316 case GREP_NODE_NOT:
0ab7befa
JH
317 h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
318 break;
83b5d2f5 319 case GREP_NODE_AND:
0ab7befa
JH
320 if (!collect_hits)
321 return (match_expr_eval(o, x->u.binary.left,
322 bol, eol, ctx, 0) &&
323 match_expr_eval(o, x->u.binary.right,
324 bol, eol, ctx, 0));
325 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
326 h &= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 0);
327 break;
83b5d2f5 328 case GREP_NODE_OR:
0ab7befa
JH
329 if (!collect_hits)
330 return (match_expr_eval(o, x->u.binary.left,
331 bol, eol, ctx, 0) ||
332 match_expr_eval(o, x->u.binary.right,
333 bol, eol, ctx, 0));
334 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
335 x->u.binary.left->hit |= h;
336 h |= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 1);
337 break;
338 default:
339 die("Unexpected node type (internal error) %d\n", x->node);
83b5d2f5 340 }
0ab7befa
JH
341 if (collect_hits)
342 x->hit |= h;
343 return h;
83b5d2f5
JH
344}
345
480c1ca6 346static int match_expr(struct grep_opt *opt, char *bol, char *eol,
0ab7befa 347 enum grep_context ctx, int collect_hits)
83b5d2f5
JH
348{
349 struct grep_expr *x = opt->pattern_expression;
0ab7befa 350 return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
83b5d2f5
JH
351}
352
480c1ca6 353static int match_line(struct grep_opt *opt, char *bol, char *eol,
0ab7befa 354 enum grep_context ctx, int collect_hits)
83b5d2f5
JH
355{
356 struct grep_pat *p;
357 if (opt->extended)
0ab7befa
JH
358 return match_expr(opt, bol, eol, ctx, collect_hits);
359
360 /* we do not call with collect_hits without being extended */
83b5d2f5 361 for (p = opt->pattern_list; p; p = p->next) {
480c1ca6 362 if (match_one_pattern(opt, p, bol, eol, ctx))
83b5d2f5
JH
363 return 1;
364 }
365 return 0;
366}
367
0ab7befa
JH
368static int grep_buffer_1(struct grep_opt *opt, const char *name,
369 char *buf, unsigned long size, int collect_hits)
83b5d2f5
JH
370{
371 char *bol = buf;
372 unsigned long left = size;
373 unsigned lno = 1;
374 struct pre_context_line {
375 char *bol;
376 char *eol;
377 } *prev = NULL, *pcl;
378 unsigned last_hit = 0;
379 unsigned last_shown = 0;
380 int binary_match_only = 0;
381 const char *hunk_mark = "";
382 unsigned count = 0;
480c1ca6 383 enum grep_context ctx = GREP_CONTEXT_HEAD;
83b5d2f5
JH
384
385 if (buffer_is_binary(buf, size)) {
386 switch (opt->binary) {
387 case GREP_BINARY_DEFAULT:
388 binary_match_only = 1;
389 break;
390 case GREP_BINARY_NOMATCH:
391 return 0; /* Assume unmatch */
392 break;
393 default:
394 break;
395 }
396 }
397
398 if (opt->pre_context)
399 prev = xcalloc(opt->pre_context, sizeof(*prev));
400 if (opt->pre_context || opt->post_context)
401 hunk_mark = "--\n";
402
403 while (left) {
404 char *eol, ch;
0ab7befa 405 int hit;
83b5d2f5
JH
406
407 eol = end_of_line(bol, &left);
408 ch = *eol;
409 *eol = 0;
410
480c1ca6
JH
411 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
412 ctx = GREP_CONTEXT_BODY;
413
0ab7befa 414 hit = match_line(opt, bol, eol, ctx, collect_hits);
83b5d2f5
JH
415 *eol = ch;
416
0ab7befa
JH
417 if (collect_hits)
418 goto next_line;
419
83b5d2f5
JH
420 /* "grep -v -e foo -e bla" should list lines
421 * that do not have either, so inversion should
422 * be done outside.
423 */
424 if (opt->invert)
425 hit = !hit;
426 if (opt->unmatch_name_only) {
427 if (hit)
428 return 0;
429 goto next_line;
430 }
431 if (hit) {
432 count++;
433 if (opt->status_only)
434 return 1;
435 if (binary_match_only) {
436 printf("Binary file %s matches\n", name);
437 return 1;
438 }
439 if (opt->name_only) {
440 printf("%s\n", name);
441 return 1;
442 }
443 /* Hit at this line. If we haven't shown the
444 * pre-context lines, we would need to show them.
445 * When asked to do "count", this still show
446 * the context which is nonsense, but the user
447 * deserves to get that ;-).
448 */
449 if (opt->pre_context) {
450 unsigned from;
451 if (opt->pre_context < lno)
452 from = lno - opt->pre_context;
453 else
454 from = 1;
455 if (from <= last_shown)
456 from = last_shown + 1;
457 if (last_shown && from != last_shown + 1)
458 printf(hunk_mark);
459 while (from < lno) {
460 pcl = &prev[lno-from-1];
461 show_line(opt, pcl->bol, pcl->eol,
462 name, from, '-');
463 from++;
464 }
465 last_shown = lno-1;
466 }
467 if (last_shown && lno != last_shown + 1)
468 printf(hunk_mark);
469 if (!opt->count)
470 show_line(opt, bol, eol, name, lno, ':');
471 last_shown = last_hit = lno;
472 }
473 else if (last_hit &&
474 lno <= last_hit + opt->post_context) {
475 /* If the last hit is within the post context,
476 * we need to show this line.
477 */
478 if (last_shown && lno != last_shown + 1)
479 printf(hunk_mark);
480 show_line(opt, bol, eol, name, lno, '-');
481 last_shown = lno;
482 }
483 if (opt->pre_context) {
484 memmove(prev+1, prev,
485 (opt->pre_context-1) * sizeof(*prev));
486 prev->bol = bol;
487 prev->eol = eol;
488 }
489
490 next_line:
491 bol = eol + 1;
492 if (!left)
493 break;
494 left--;
495 lno++;
496 }
497
b48fb5b6 498 free(prev);
0ab7befa
JH
499 if (collect_hits)
500 return 0;
b48fb5b6 501
83b5d2f5
JH
502 if (opt->status_only)
503 return 0;
504 if (opt->unmatch_name_only) {
505 /* We did not see any hit, so we want to show this */
506 printf("%s\n", name);
507 return 1;
508 }
509
510 /* NEEDSWORK:
511 * The real "grep -c foo *.c" gives many "bar.c:0" lines,
512 * which feels mostly useless but sometimes useful. Maybe
513 * make it another option? For now suppress them.
514 */
515 if (opt->count && count)
516 printf("%s:%u\n", name, count);
517 return !!last_hit;
518}
519
0ab7befa
JH
520static void clr_hit_marker(struct grep_expr *x)
521{
522 /* All-hit markers are meaningful only at the very top level
523 * OR node.
524 */
525 while (1) {
526 x->hit = 0;
527 if (x->node != GREP_NODE_OR)
528 return;
529 x->u.binary.left->hit = 0;
530 x = x->u.binary.right;
531 }
532}
533
534static int chk_hit_marker(struct grep_expr *x)
535{
536 /* Top level nodes have hit markers. See if they all are hits */
537 while (1) {
538 if (x->node != GREP_NODE_OR)
539 return x->hit;
540 if (!x->u.binary.left->hit)
541 return 0;
542 x = x->u.binary.right;
543 }
544}
545
546int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
547{
548 /*
549 * we do not have to do the two-pass grep when we do not check
550 * buffer-wide "all-match".
551 */
552 if (!opt->all_match)
553 return grep_buffer_1(opt, name, buf, size, 0);
554
555 /* Otherwise the toplevel "or" terms hit a bit differently.
556 * We first clear hit markers from them.
557 */
558 clr_hit_marker(opt->pattern_expression);
559 grep_buffer_1(opt, name, buf, size, 1);
560
561 if (!chk_hit_marker(opt->pattern_expression))
562 return 0;
563
564 return grep_buffer_1(opt, name, buf, size, 0);
565}