Merge branch 'maint-1.5.6' into maint-1.6.0
[git/spearce.git] / grep.c
bloba4edacad8b4e4365bc22266521e26f3b617d53b5
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 if (!p)
58 return NULL;
59 switch (p->token) {
60 case GREP_PATTERN: /* atom */
61 case GREP_PATTERN_HEAD:
62 case GREP_PATTERN_BODY:
63 x = xcalloc(1, sizeof (struct grep_expr));
64 x->node = GREP_NODE_ATOM;
65 x->u.atom = p;
66 *list = p->next;
67 return x;
68 case GREP_OPEN_PAREN:
69 *list = p->next;
70 x = compile_pattern_or(list);
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 if (!p)
87 return NULL;
88 switch (p->token) {
89 case GREP_NOT:
90 if (!p->next)
91 die("--not not followed by pattern expression");
92 *list = p->next;
93 x = xcalloc(1, sizeof (struct grep_expr));
94 x->node = GREP_NODE_NOT;
95 x->u.unary = compile_pattern_not(list);
96 if (!x->u.unary)
97 die("--not followed by non pattern expression");
98 return x;
99 default:
100 return compile_pattern_atom(list);
104 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
106 struct grep_pat *p;
107 struct grep_expr *x, *y, *z;
109 x = compile_pattern_not(list);
110 p = *list;
111 if (p && p->token == GREP_AND) {
112 if (!p->next)
113 die("--and not followed by pattern expression");
114 *list = p->next;
115 y = compile_pattern_and(list);
116 if (!y)
117 die("--and not followed by pattern expression");
118 z = xcalloc(1, sizeof (struct grep_expr));
119 z->node = GREP_NODE_AND;
120 z->u.binary.left = x;
121 z->u.binary.right = y;
122 return z;
124 return x;
127 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
129 struct grep_pat *p;
130 struct grep_expr *x, *y, *z;
132 x = compile_pattern_and(list);
133 p = *list;
134 if (x && p && p->token != GREP_CLOSE_PAREN) {
135 y = compile_pattern_or(list);
136 if (!y)
137 die("not a pattern expression %s", p->pattern);
138 z = xcalloc(1, sizeof (struct grep_expr));
139 z->node = GREP_NODE_OR;
140 z->u.binary.left = x;
141 z->u.binary.right = y;
142 return z;
144 return x;
147 static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
149 return compile_pattern_or(list);
152 void compile_grep_patterns(struct grep_opt *opt)
154 struct grep_pat *p;
156 if (opt->all_match)
157 opt->extended = 1;
159 for (p = opt->pattern_list; p; p = p->next) {
160 switch (p->token) {
161 case GREP_PATTERN: /* atom */
162 case GREP_PATTERN_HEAD:
163 case GREP_PATTERN_BODY:
164 if (!opt->fixed)
165 compile_regexp(p, opt);
166 break;
167 default:
168 opt->extended = 1;
169 break;
173 if (!opt->extended)
174 return;
176 /* Then bundle them up in an expression.
177 * A classic recursive descent parser would do.
179 p = opt->pattern_list;
180 opt->pattern_expression = compile_pattern_expr(&p);
181 if (p)
182 die("incomplete pattern expression: %s", p->pattern);
185 static void free_pattern_expr(struct grep_expr *x)
187 switch (x->node) {
188 case GREP_NODE_ATOM:
189 break;
190 case GREP_NODE_NOT:
191 free_pattern_expr(x->u.unary);
192 break;
193 case GREP_NODE_AND:
194 case GREP_NODE_OR:
195 free_pattern_expr(x->u.binary.left);
196 free_pattern_expr(x->u.binary.right);
197 break;
199 free(x);
202 void free_grep_patterns(struct grep_opt *opt)
204 struct grep_pat *p, *n;
206 for (p = opt->pattern_list; p; p = n) {
207 n = p->next;
208 switch (p->token) {
209 case GREP_PATTERN: /* atom */
210 case GREP_PATTERN_HEAD:
211 case GREP_PATTERN_BODY:
212 regfree(&p->regexp);
213 break;
214 default:
215 break;
217 free(p);
220 if (!opt->extended)
221 return;
222 free_pattern_expr(opt->pattern_expression);
225 static char *end_of_line(char *cp, unsigned long *left)
227 unsigned long l = *left;
228 while (l && *cp != '\n') {
229 l--;
230 cp++;
232 *left = l;
233 return cp;
236 static int word_char(char ch)
238 return isalnum(ch) || ch == '_';
241 static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
242 const char *name, unsigned lno, char sign)
244 if (opt->pathname)
245 printf("%s%c", name, sign);
246 if (opt->linenum)
247 printf("%d%c", lno, sign);
248 printf("%.*s\n", (int)(eol-bol), bol);
251 static int fixmatch(const char *pattern, char *line, regmatch_t *match)
253 char *hit = strstr(line, pattern);
254 if (!hit) {
255 match->rm_so = match->rm_eo = -1;
256 return REG_NOMATCH;
258 else {
259 match->rm_so = hit - line;
260 match->rm_eo = match->rm_so + strlen(pattern);
261 return 0;
265 static int strip_timestamp(char *bol, char **eol_p)
267 char *eol = *eol_p;
268 int ch;
270 while (bol < --eol) {
271 if (*eol != '>')
272 continue;
273 *eol_p = ++eol;
274 ch = *eol;
275 *eol = '\0';
276 return ch;
278 return 0;
281 static struct {
282 const char *field;
283 size_t len;
284 } header_field[] = {
285 { "author ", 7 },
286 { "committer ", 10 },
289 static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
291 int hit = 0;
292 int at_true_bol = 1;
293 int saved_ch = 0;
294 regmatch_t pmatch[10];
296 if ((p->token != GREP_PATTERN) &&
297 ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
298 return 0;
300 if (p->token == GREP_PATTERN_HEAD) {
301 const char *field;
302 size_t len;
303 assert(p->field < ARRAY_SIZE(header_field));
304 field = header_field[p->field].field;
305 len = header_field[p->field].len;
306 if (strncmp(bol, field, len))
307 return 0;
308 bol += len;
309 saved_ch = strip_timestamp(bol, &eol);
312 again:
313 if (!opt->fixed) {
314 regex_t *exp = &p->regexp;
315 hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
316 pmatch, 0);
318 else {
319 hit = !fixmatch(p->pattern, bol, pmatch);
322 if (hit && opt->word_regexp) {
323 if ((pmatch[0].rm_so < 0) ||
324 (eol - bol) <= pmatch[0].rm_so ||
325 (pmatch[0].rm_eo < 0) ||
326 (eol - bol) < pmatch[0].rm_eo)
327 die("regexp returned nonsense");
329 /* Match beginning must be either beginning of the
330 * line, or at word boundary (i.e. the last char must
331 * not be a word char). Similarly, match end must be
332 * either end of the line, or at word boundary
333 * (i.e. the next char must not be a word char).
335 if ( ((pmatch[0].rm_so == 0 && at_true_bol) ||
336 !word_char(bol[pmatch[0].rm_so-1])) &&
337 ((pmatch[0].rm_eo == (eol-bol)) ||
338 !word_char(bol[pmatch[0].rm_eo])) )
340 else
341 hit = 0;
343 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
344 /* There could be more than one match on the
345 * line, and the first match might not be
346 * strict word match. But later ones could be!
348 bol = pmatch[0].rm_so + bol + 1;
349 at_true_bol = 0;
350 goto again;
353 if (p->token == GREP_PATTERN_HEAD && saved_ch)
354 *eol = saved_ch;
355 return hit;
358 static int match_expr_eval(struct grep_opt *o,
359 struct grep_expr *x,
360 char *bol, char *eol,
361 enum grep_context ctx,
362 int collect_hits)
364 int h = 0;
366 if (!x)
367 die("Not a valid grep expression");
368 switch (x->node) {
369 case GREP_NODE_ATOM:
370 h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
371 break;
372 case GREP_NODE_NOT:
373 h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
374 break;
375 case GREP_NODE_AND:
376 if (!collect_hits)
377 return (match_expr_eval(o, x->u.binary.left,
378 bol, eol, ctx, 0) &&
379 match_expr_eval(o, x->u.binary.right,
380 bol, eol, ctx, 0));
381 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
382 h &= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 0);
383 break;
384 case GREP_NODE_OR:
385 if (!collect_hits)
386 return (match_expr_eval(o, x->u.binary.left,
387 bol, eol, ctx, 0) ||
388 match_expr_eval(o, x->u.binary.right,
389 bol, eol, ctx, 0));
390 h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
391 x->u.binary.left->hit |= h;
392 h |= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 1);
393 break;
394 default:
395 die("Unexpected node type (internal error) %d\n", x->node);
397 if (collect_hits)
398 x->hit |= h;
399 return h;
402 static int match_expr(struct grep_opt *opt, char *bol, char *eol,
403 enum grep_context ctx, int collect_hits)
405 struct grep_expr *x = opt->pattern_expression;
406 return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
409 static int match_line(struct grep_opt *opt, char *bol, char *eol,
410 enum grep_context ctx, int collect_hits)
412 struct grep_pat *p;
413 if (opt->extended)
414 return match_expr(opt, bol, eol, ctx, collect_hits);
416 /* we do not call with collect_hits without being extended */
417 for (p = opt->pattern_list; p; p = p->next) {
418 if (match_one_pattern(opt, p, bol, eol, ctx))
419 return 1;
421 return 0;
424 static int grep_buffer_1(struct grep_opt *opt, const char *name,
425 char *buf, unsigned long size, int collect_hits)
427 char *bol = buf;
428 unsigned long left = size;
429 unsigned lno = 1;
430 struct pre_context_line {
431 char *bol;
432 char *eol;
433 } *prev = NULL, *pcl;
434 unsigned last_hit = 0;
435 unsigned last_shown = 0;
436 int binary_match_only = 0;
437 const char *hunk_mark = "";
438 unsigned count = 0;
439 enum grep_context ctx = GREP_CONTEXT_HEAD;
441 if (buffer_is_binary(buf, size)) {
442 switch (opt->binary) {
443 case GREP_BINARY_DEFAULT:
444 binary_match_only = 1;
445 break;
446 case GREP_BINARY_NOMATCH:
447 return 0; /* Assume unmatch */
448 break;
449 default:
450 break;
454 if (opt->pre_context)
455 prev = xcalloc(opt->pre_context, sizeof(*prev));
456 if (opt->pre_context || opt->post_context)
457 hunk_mark = "--\n";
459 while (left) {
460 char *eol, ch;
461 int hit;
463 eol = end_of_line(bol, &left);
464 ch = *eol;
465 *eol = 0;
467 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
468 ctx = GREP_CONTEXT_BODY;
470 hit = match_line(opt, bol, eol, ctx, collect_hits);
471 *eol = ch;
473 if (collect_hits)
474 goto next_line;
476 /* "grep -v -e foo -e bla" should list lines
477 * that do not have either, so inversion should
478 * be done outside.
480 if (opt->invert)
481 hit = !hit;
482 if (opt->unmatch_name_only) {
483 if (hit)
484 return 0;
485 goto next_line;
487 if (hit) {
488 count++;
489 if (opt->status_only)
490 return 1;
491 if (binary_match_only) {
492 printf("Binary file %s matches\n", name);
493 return 1;
495 if (opt->name_only) {
496 printf("%s\n", name);
497 return 1;
499 /* Hit at this line. If we haven't shown the
500 * pre-context lines, we would need to show them.
501 * When asked to do "count", this still show
502 * the context which is nonsense, but the user
503 * deserves to get that ;-).
505 if (opt->pre_context) {
506 unsigned from;
507 if (opt->pre_context < lno)
508 from = lno - opt->pre_context;
509 else
510 from = 1;
511 if (from <= last_shown)
512 from = last_shown + 1;
513 if (last_shown && from != last_shown + 1)
514 fputs(hunk_mark, stdout);
515 while (from < lno) {
516 pcl = &prev[lno-from-1];
517 show_line(opt, pcl->bol, pcl->eol,
518 name, from, '-');
519 from++;
521 last_shown = lno-1;
523 if (last_shown && lno != last_shown + 1)
524 fputs(hunk_mark, stdout);
525 if (!opt->count)
526 show_line(opt, bol, eol, name, lno, ':');
527 last_shown = last_hit = lno;
529 else if (last_hit &&
530 lno <= last_hit + opt->post_context) {
531 /* If the last hit is within the post context,
532 * we need to show this line.
534 if (last_shown && lno != last_shown + 1)
535 fputs(hunk_mark, stdout);
536 show_line(opt, bol, eol, name, lno, '-');
537 last_shown = lno;
539 if (opt->pre_context) {
540 memmove(prev+1, prev,
541 (opt->pre_context-1) * sizeof(*prev));
542 prev->bol = bol;
543 prev->eol = eol;
546 next_line:
547 bol = eol + 1;
548 if (!left)
549 break;
550 left--;
551 lno++;
554 free(prev);
555 if (collect_hits)
556 return 0;
558 if (opt->status_only)
559 return 0;
560 if (opt->unmatch_name_only) {
561 /* We did not see any hit, so we want to show this */
562 printf("%s\n", name);
563 return 1;
566 /* NEEDSWORK:
567 * The real "grep -c foo *.c" gives many "bar.c:0" lines,
568 * which feels mostly useless but sometimes useful. Maybe
569 * make it another option? For now suppress them.
571 if (opt->count && count)
572 printf("%s:%u\n", name, count);
573 return !!last_hit;
576 static void clr_hit_marker(struct grep_expr *x)
578 /* All-hit markers are meaningful only at the very top level
579 * OR node.
581 while (1) {
582 x->hit = 0;
583 if (x->node != GREP_NODE_OR)
584 return;
585 x->u.binary.left->hit = 0;
586 x = x->u.binary.right;
590 static int chk_hit_marker(struct grep_expr *x)
592 /* Top level nodes have hit markers. See if they all are hits */
593 while (1) {
594 if (x->node != GREP_NODE_OR)
595 return x->hit;
596 if (!x->u.binary.left->hit)
597 return 0;
598 x = x->u.binary.right;
602 int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
605 * we do not have to do the two-pass grep when we do not check
606 * buffer-wide "all-match".
608 if (!opt->all_match)
609 return grep_buffer_1(opt, name, buf, size, 0);
611 /* Otherwise the toplevel "or" terms hit a bit differently.
612 * We first clear hit markers from them.
614 clr_hit_marker(opt->pattern_expression);
615 grep_buffer_1(opt, name, buf, size, 1);
617 if (!chk_hit_marker(opt->pattern_expression))
618 return 0;
620 return grep_buffer_1(opt, name, buf, size, 0);