grep.c

   1 #include "cache.h"
   2 #include "grep.h"
   3 #include "userdiff.h"
   4 #include "xdiff-interface.h"
   5
   6 void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field field, const char *pat)
   7 {
   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;
  17 }
  18
  19 void append_grep_pattern(struct grep_opt *opt, const char *pat,
  20                          const char *origin, int no, enum grep_pat_token t)
  21 {
  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;
  30 }
  31
  32 static int is_fixed(const char *s)
  33 {
  34         while (*s && !is_regex_special(*s))
  35                 s++;
  36         return !*s;
  37 }
  38
  39 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
  40 {
  41         int err;
  42
  43         p->word_regexp = opt->word_regexp;
  44         p->ignore_case = opt->ignore_case;
  45
  46         if (opt->fixed || is_fixed(p->pattern))
  47                 p->fixed = 1;
  48         if (opt->regflags & REG_ICASE)
  49                 p->fixed = 0;
  50         if (p->fixed)
  51                 return;
  52
  53         err = regcomp(&p->regexp, p->pattern, opt->regflags);
  54         if (err) {
  55                 char errbuf[1024];
  56                 char where[1024];
  57                 if (p->no)
  58                         sprintf(where, "In '%s' at %d, ",
  59                                 p->origin, p->no);
  60                 else if (p->origin)
  61                         sprintf(where, "%s, ", p->origin);
  62                 else
  63                         where[0] = 0;
  64                 regerror(err, &p->regexp, errbuf, 1024);
  65                 regfree(&p->regexp);
  66                 die("%s'%s': %s", where, p->pattern, errbuf);
  67         }
  68 }
  69
  70 static struct grep_expr *compile_pattern_or(struct grep_pat **);
  71 static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
  72 {
  73         struct grep_pat *p;
  74         struct grep_expr *x;
  75
  76         p = *list;
  77         if (!p)
  78                 return NULL;
  79         switch (p->token) {
  80         case GREP_PATTERN: /* atom */
  81         case GREP_PATTERN_HEAD:
  82         case GREP_PATTERN_BODY:
  83                 x = xcalloc(1, sizeof (struct grep_expr));
  84                 x->node = GREP_NODE_ATOM;
  85                 x->u.atom = p;
  86                 *list = p->next;
  87                 return x;
  88         case GREP_OPEN_PAREN:
  89                 *list = p->next;
  90                 x = compile_pattern_or(list);
  91                 if (!*list || (*list)->token != GREP_CLOSE_PAREN)
  92                         die("unmatched parenthesis");
  93                 *list = (*list)->next;
  94                 return x;
  95         default:
  96                 return NULL;
  97         }
  98 }
  99
 100 static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 101 {
 102         struct grep_pat *p;
 103         struct grep_expr *x;
 104
 105         p = *list;
 106         if (!p)
 107                 return NULL;
 108         switch (p->token) {
 109         case GREP_NOT:
 110                 if (!p->next)
 111                         die("--not not followed by pattern expression");
 112                 *list = p->next;
 113                 x = xcalloc(1, sizeof (struct grep_expr));
 114                 x->node = GREP_NODE_NOT;
 115                 x->u.unary = compile_pattern_not(list);
 116                 if (!x->u.unary)
 117                         die("--not followed by non pattern expression");
 118                 return x;
 119         default:
 120                 return compile_pattern_atom(list);
 121         }
 122 }
 123
 124 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 125 {
 126         struct grep_pat *p;
 127         struct grep_expr *x, *y, *z;
 128
 129         x = compile_pattern_not(list);
 130         p = *list;
 131         if (p && p->token == GREP_AND) {
 132                 if (!p->next)
 133                         die("--and not followed by pattern expression");
 134                 *list = p->next;
 135                 y = compile_pattern_and(list);
 136                 if (!y)
 137                         die("--and not followed by pattern expression");
 138                 z = xcalloc(1, sizeof (struct grep_expr));
 139                 z->node = GREP_NODE_AND;
 140                 z->u.binary.left = x;
 141                 z->u.binary.right = y;
 142                 return z;
 143         }
 144         return x;
 145 }
 146
 147 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 148 {
 149         struct grep_pat *p;
 150         struct grep_expr *x, *y, *z;
 151
 152         x = compile_pattern_and(list);
 153         p = *list;
 154         if (x && p && p->token != GREP_CLOSE_PAREN) {
 155                 y = compile_pattern_or(list);
 156                 if (!y)
 157                         die("not a pattern expression %s", p->pattern);
 158                 z = xcalloc(1, sizeof (struct grep_expr));
 159                 z->node = GREP_NODE_OR;
 160                 z->u.binary.left = x;
 161                 z->u.binary.right = y;
 162                 return z;
 163         }
 164         return x;
 165 }
 166
 167 static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 168 {
 169         return compile_pattern_or(list);
 170 }
 171
 172 void compile_grep_patterns(struct grep_opt *opt)
 173 {
 174         struct grep_pat *p;
 175
 176         if (opt->all_match)
 177                 opt->extended = 1;
 178
 179         for (p = opt->pattern_list; p; p = p->next) {
 180                 switch (p->token) {
 181                 case GREP_PATTERN: /* atom */
 182                 case GREP_PATTERN_HEAD:
 183                 case GREP_PATTERN_BODY:
 184                         compile_regexp(p, opt);
 185                         break;
 186                 default:
 187                         opt->extended = 1;
 188                         break;
 189                 }
 190         }
 191
 192         if (!opt->extended)
 193                 return;
 194
 195         /* Then bundle them up in an expression.
 196          * A classic recursive descent parser would do.
 197          */
 198         p = opt->pattern_list;
 199         if (p)
 200                 opt->pattern_expression = compile_pattern_expr(&p);
 201         if (p)
 202                 die("incomplete pattern expression: %s", p->pattern);
 203 }
 204
 205 static void free_pattern_expr(struct grep_expr *x)
 206 {
 207         switch (x->node) {
 208         case GREP_NODE_ATOM:
 209                 break;
 210         case GREP_NODE_NOT:
 211                 free_pattern_expr(x->u.unary);
 212                 break;
 213         case GREP_NODE_AND:
 214         case GREP_NODE_OR:
 215                 free_pattern_expr(x->u.binary.left);
 216                 free_pattern_expr(x->u.binary.right);
 217                 break;
 218         }
 219         free(x);
 220 }
 221
 222 void free_grep_patterns(struct grep_opt *opt)
 223 {
 224         struct grep_pat *p, *n;
 225
 226         for (p = opt->pattern_list; p; p = n) {
 227                 n = p->next;
 228                 switch (p->token) {
 229                 case GREP_PATTERN: /* atom */
 230                 case GREP_PATTERN_HEAD:
 231                 case GREP_PATTERN_BODY:
 232                         regfree(&p->regexp);
 233                         break;
 234                 default:
 235                         break;
 236                 }
 237                 free(p);
 238         }
 239
 240         if (!opt->extended)
 241                 return;
 242         free_pattern_expr(opt->pattern_expression);
 243 }
 244
 245 static char *end_of_line(char *cp, unsigned long *left)
 246 {
 247         unsigned long l = *left;
 248         while (l && *cp != '\n') {
 249                 l--;
 250                 cp++;
 251         }
 252         *left = l;
 253         return cp;
 254 }
 255
 256 static int word_char(char ch)
 257 {
 258         return isalnum(ch) || ch == '_';
 259 }
 260
 261 static void show_name(struct grep_opt *opt, const char *name)
 262 {
 263         printf("%s%c", name, opt->null_following_name ? '\0' : '\n');
 264 }
 265
 266
 267 static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t *match)
 268 {
 269         char *hit;
 270         if (ignore_case)
 271                 hit = strcasestr(line, pattern);
 272         else
 273                 hit = strstr(line, pattern);
 274
 275         if (!hit) {
 276                 match->rm_so = match->rm_eo = -1;
 277                 return REG_NOMATCH;
 278         }
 279         else {
 280                 match->rm_so = hit - line;
 281                 match->rm_eo = match->rm_so + strlen(pattern);
 282                 return 0;
 283         }
 284 }
 285
 286 static int strip_timestamp(char *bol, char **eol_p)
 287 {
 288         char *eol = *eol_p;
 289         int ch;
 290
 291         while (bol < --eol) {
 292                 if (*eol != '>')
 293                         continue;
 294                 *eol_p = ++eol;
 295                 ch = *eol;
 296                 *eol = '\0';
 297                 return ch;
 298         }
 299         return 0;
 300 }
 301
 302 static struct {
 303         const char *field;
 304         size_t len;
 305 } header_field[] = {
 306         { "author ", 7 },
 307         { "committer ", 10 },
 308 };
 309
 310 static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 311                              enum grep_context ctx,
 312                              regmatch_t *pmatch, int eflags)
 313 {
 314         int hit = 0;
 315         int saved_ch = 0;
 316         const char *start = bol;
 317
 318         if ((p->token != GREP_PATTERN) &&
 319             ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 320                 return 0;
 321
 322         if (p->token == GREP_PATTERN_HEAD) {
 323                 const char *field;
 324                 size_t len;
 325                 assert(p->field < ARRAY_SIZE(header_field));
 326                 field = header_field[p->field].field;
 327                 len = header_field[p->field].len;
 328                 if (strncmp(bol, field, len))
 329                         return 0;
 330                 bol += len;
 331                 saved_ch = strip_timestamp(bol, &eol);
 332         }
 333
 334  again:
 335         if (p->fixed)
 336                 hit = !fixmatch(p->pattern, bol, p->ignore_case, pmatch);
 337         else
 338                 hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
 339
 340         if (hit && p->word_regexp) {
 341                 if ((pmatch[0].rm_so < 0) ||
 342                     (eol - bol) < pmatch[0].rm_so ||
 343                     (pmatch[0].rm_eo < 0) ||
 344                     (eol - bol) < pmatch[0].rm_eo)
 345                         die("regexp returned nonsense");
 346
 347                 /* Match beginning must be either beginning of the
 348                  * line, or at word boundary (i.e. the last char must
 349                  * not be a word char).  Similarly, match end must be
 350                  * either end of the line, or at word boundary
 351                  * (i.e. the next char must not be a word char).
 352                  */
 353                 if ( ((pmatch[0].rm_so == 0) ||
 354                       !word_char(bol[pmatch[0].rm_so-1])) &&
 355                      ((pmatch[0].rm_eo == (eol-bol)) ||
 356                       !word_char(bol[pmatch[0].rm_eo])) )
 357                         ;
 358                 else
 359                         hit = 0;
 360
 361                 /* Words consist of at least one character. */
 362                 if (pmatch->rm_so == pmatch->rm_eo)
 363                         hit = 0;
 364
 365                 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 366                         /* There could be more than one match on the
 367                          * line, and the first match might not be
 368                          * strict word match.  But later ones could be!
 369                          * Forward to the next possible start, i.e. the
 370                          * next position following a non-word char.
 371                          */
 372                         bol = pmatch[0].rm_so + bol + 1;
 373                         while (word_char(bol[-1]) && bol < eol)
 374                                 bol++;
 375                         eflags |= REG_NOTBOL;
 376                         if (bol < eol)
 377                                 goto again;
 378                 }
 379         }
 380         if (p->token == GREP_PATTERN_HEAD && saved_ch)
 381                 *eol = saved_ch;
 382         if (hit) {
 383                 pmatch[0].rm_so += bol - start;
 384                 pmatch[0].rm_eo += bol - start;
 385         }
 386         return hit;
 387 }
 388
 389 static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 390                            enum grep_context ctx, int collect_hits)
 391 {
 392         int h = 0;
 393         regmatch_t match;
 394
 395         if (!x)
 396                 die("Not a valid grep expression");
 397         switch (x->node) {
 398         case GREP_NODE_ATOM:
 399                 h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 400                 break;
 401         case GREP_NODE_NOT:
 402                 h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 403                 break;
 404         case GREP_NODE_AND:
 405                 if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 406                         return 0;
 407                 h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 408                 break;
 409         case GREP_NODE_OR:
 410                 if (!collect_hits)
 411                         return (match_expr_eval(x->u.binary.left,
 412                                                 bol, eol, ctx, 0) ||
 413                                 match_expr_eval(x->u.binary.right,
 414                                                 bol, eol, ctx, 0));
 415                 h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 416                 x->u.binary.left->hit |= h;
 417                 h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 418                 break;
 419         default:
 420                 die("Unexpected node type (internal error) %d", x->node);
 421         }
 422         if (collect_hits)
 423                 x->hit |= h;
 424         return h;
 425 }
 426
 427 static int match_expr(struct grep_opt *opt, char *bol, char *eol,
 428                       enum grep_context ctx, int collect_hits)
 429 {
 430         struct grep_expr *x = opt->pattern_expression;
 431         return match_expr_eval(x, bol, eol, ctx, collect_hits);
 432 }
 433
 434 static int match_line(struct grep_opt *opt, char *bol, char *eol,
 435                       enum grep_context ctx, int collect_hits)
 436 {
 437         struct grep_pat *p;
 438         regmatch_t match;
 439
 440         if (opt->extended)
 441                 return match_expr(opt, bol, eol, ctx, collect_hits);
 442
 443         /* we do not call with collect_hits without being extended */
 444         for (p = opt->pattern_list; p; p = p->next) {
 445                 if (match_one_pattern(p, bol, eol, ctx, &match, 0))
 446                         return 1;
 447         }
 448         return 0;
 449 }
 450
 451 static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
 452                               enum grep_context ctx,
 453                               regmatch_t *pmatch, int eflags)
 454 {
 455         regmatch_t match;
 456
 457         if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
 458                 return 0;
 459         if (match.rm_so < 0 || match.rm_eo < 0)
 460                 return 0;
 461         if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
 462                 if (match.rm_so > pmatch->rm_so)
 463                         return 1;
 464                 if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
 465                         return 1;
 466         }
 467         pmatch->rm_so = match.rm_so;
 468         pmatch->rm_eo = match.rm_eo;
 469         return 1;
 470 }
 471
 472 static int next_match(struct grep_opt *opt, char *bol, char *eol,
 473                       enum grep_context ctx, regmatch_t *pmatch, int eflags)
 474 {
 475         struct grep_pat *p;
 476         int hit = 0;
 477
 478         pmatch->rm_so = pmatch->rm_eo = -1;
 479         if (bol < eol) {
 480                 for (p = opt->pattern_list; p; p = p->next) {
 481                         switch (p->token) {
 482                         case GREP_PATTERN: /* atom */
 483                         case GREP_PATTERN_HEAD:
 484                         case GREP_PATTERN_BODY:
 485                                 hit |= match_next_pattern(p, bol, eol, ctx,
 486                                                           pmatch, eflags);
 487                                 break;
 488                         default:
 489                                 break;
 490                         }
 491                 }
 492         }
 493         return hit;
 494 }
 495
 496 static void show_line(struct grep_opt *opt, char *bol, char *eol,
 497                       const char *name, unsigned lno, char sign)
 498 {
 499         int rest = eol - bol;
 500
 501         if (opt->pre_context || opt->post_context) {
 502                 if (opt->last_shown == 0) {
 503                         if (opt->show_hunk_mark)
 504                                 fputs("--\n", stdout);
 505                         else
 506                                 opt->show_hunk_mark = 1;
 507                 } else if (lno > opt->last_shown + 1)
 508                         fputs("--\n", stdout);
 509         }
 510         opt->last_shown = lno;
 511
 512         if (opt->null_following_name)
 513                 sign = '\0';
 514         if (opt->pathname)
 515                 printf("%s%c", name, sign);
 516         if (opt->linenum)
 517                 printf("%d%c", lno, sign);
 518         if (opt->color) {
 519                 regmatch_t match;
 520                 enum grep_context ctx = GREP_CONTEXT_BODY;
 521                 int ch = *eol;
 522                 int eflags = 0;
 523
 524                 *eol = '\0';
 525                 while (next_match(opt, bol, eol, ctx, &match, eflags)) {
 526                         if (match.rm_so == match.rm_eo)
 527                                 break;
 528                         printf("%.*s%s%.*s%s",
 529                                (int)match.rm_so, bol,
 530                                opt->color_match,
 531                                (int)(match.rm_eo - match.rm_so), bol + match.rm_so,
 532                                GIT_COLOR_RESET);
 533                         bol += match.rm_eo;
 534                         rest -= match.rm_eo;
 535                         eflags = REG_NOTBOL;
 536                 }
 537                 *eol = ch;
 538         }
 539         printf("%.*s\n", rest, bol);
 540 }
 541
 542 static int match_funcname(struct grep_opt *opt, char *bol, char *eol)
 543 {
 544         xdemitconf_t *xecfg = opt->priv;
 545         if (xecfg && xecfg->find_func) {
 546                 char buf[1];
 547                 return xecfg->find_func(bol, eol - bol, buf, 1,
 548                                         xecfg->find_func_priv) >= 0;
 549         }
 550
 551         if (bol == eol)
 552                 return 0;
 553         if (isalpha(*bol) || *bol == '_' || *bol == '$')
 554                 return 1;
 555         return 0;
 556 }
 557
 558 static void show_funcname_line(struct grep_opt *opt, const char *name,
 559                                char *buf, char *bol, unsigned lno)
 560 {
 561         while (bol > buf) {
 562                 char *eol = --bol;
 563
 564                 while (bol > buf && bol[-1] != '\n')
 565                         bol--;
 566                 lno--;
 567
 568                 if (lno <= opt->last_shown)
 569                         break;
 570
 571                 if (match_funcname(opt, bol, eol)) {
 572                         show_line(opt, bol, eol, name, lno, '=');
 573                         break;
 574                 }
 575         }
 576 }
 577
 578 static void show_pre_context(struct grep_opt *opt, const char *name, char *buf,
 579                              char *bol, unsigned lno)
 580 {
 581         unsigned cur = lno, from = 1, funcname_lno = 0;
 582         int funcname_needed = opt->funcname;
 583
 584         if (opt->pre_context < lno)
 585                 from = lno - opt->pre_context;
 586         if (from <= opt->last_shown)
 587                 from = opt->last_shown + 1;
 588
 589         /* Rewind. */
 590         while (bol > buf && cur > from) {
 591                 char *eol = --bol;
 592
 593                 while (bol > buf && bol[-1] != '\n')
 594                         bol--;
 595                 cur--;
 596                 if (funcname_needed && match_funcname(opt, bol, eol)) {
 597                         funcname_lno = cur;
 598                         funcname_needed = 0;
 599                 }
 600         }
 601
 602         /* We need to look even further back to find a function signature. */
 603         if (opt->funcname && funcname_needed)
 604                 show_funcname_line(opt, name, buf, bol, cur);
 605
 606         /* Back forward. */
 607         while (cur < lno) {
 608                 char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
 609
 610                 while (*eol != '\n')
 611                         eol++;
 612                 show_line(opt, bol, eol, name, cur, sign);
 613                 bol = eol + 1;
 614                 cur++;
 615         }
 616 }
 617
 618 static int grep_buffer_1(struct grep_opt *opt, const char *name,
 619                          char *buf, unsigned long size, int collect_hits)
 620 {
 621         char *bol = buf;
 622         unsigned long left = size;
 623         unsigned lno = 1;
 624         unsigned last_hit = 0;
 625         int binary_match_only = 0;
 626         unsigned count = 0;
 627         enum grep_context ctx = GREP_CONTEXT_HEAD;
 628         xdemitconf_t xecfg;
 629
 630         opt->last_shown = 0;
 631
 632         if (buffer_is_binary(buf, size)) {
 633                 switch (opt->binary) {
 634                 case GREP_BINARY_DEFAULT:
 635                         binary_match_only = 1;
 636                         break;
 637                 case GREP_BINARY_NOMATCH:
 638                         return 0; /* Assume unmatch */
 639                         break;
 640                 default:
 641                         break;
 642                 }
 643         }
 644
 645         memset(&xecfg, 0, sizeof(xecfg));
 646         if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
 647             !opt->name_only && !binary_match_only && !collect_hits) {
 648                 struct userdiff_driver *drv = userdiff_find_by_path(name);
 649                 if (drv && drv->funcname.pattern) {
 650                         const struct userdiff_funcname *pe = &drv->funcname;
 651                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
 652                         opt->priv = &xecfg;
 653                 }
 654         }
 655
 656         while (left) {
 657                 char *eol, ch;
 658                 int hit;
 659
 660                 eol = end_of_line(bol, &left);
 661                 ch = *eol;
 662                 *eol = 0;
 663
 664                 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
 665                         ctx = GREP_CONTEXT_BODY;
 666
 667                 hit = match_line(opt, bol, eol, ctx, collect_hits);
 668                 *eol = ch;
 669
 670                 if (collect_hits)
 671                         goto next_line;
 672
 673                 /* "grep -v -e foo -e bla" should list lines
 674                  * that do not have either, so inversion should
 675                  * be done outside.
 676                  */
 677                 if (opt->invert)
 678                         hit = !hit;
 679                 if (opt->unmatch_name_only) {
 680                         if (hit)
 681                                 return 0;
 682                         goto next_line;
 683                 }
 684                 if (hit) {
 685                         count++;
 686                         if (opt->status_only)
 687                                 return 1;
 688                         if (binary_match_only) {
 689                                 printf("Binary file %s matches\n", name);
 690                                 return 1;
 691                         }
 692                         if (opt->name_only) {
 693                                 show_name(opt, name);
 694                                 return 1;
 695                         }
 696                         /* Hit at this line.  If we haven't shown the
 697                          * pre-context lines, we would need to show them.
 698                          * When asked to do "count", this still show
 699                          * the context which is nonsense, but the user
 700                          * deserves to get that ;-).
 701                          */
 702                         if (opt->pre_context)
 703                                 show_pre_context(opt, name, buf, bol, lno);
 704                         else if (opt->funcname)
 705                                 show_funcname_line(opt, name, buf, bol, lno);
 706                         if (!opt->count)
 707                                 show_line(opt, bol, eol, name, lno, ':');
 708                         last_hit = lno;
 709                 }
 710                 else if (last_hit &&
 711                          lno <= last_hit + opt->post_context) {
 712                         /* If the last hit is within the post context,
 713                          * we need to show this line.
 714                          */
 715                         show_line(opt, bol, eol, name, lno, '-');
 716                 }
 717
 718         next_line:
 719                 bol = eol + 1;
 720                 if (!left)
 721                         break;
 722                 left--;
 723                 lno++;
 724         }
 725
 726         if (collect_hits)
 727                 return 0;
 728
 729         if (opt->status_only)
 730                 return 0;
 731         if (opt->unmatch_name_only) {
 732                 /* We did not see any hit, so we want to show this */
 733                 show_name(opt, name);
 734                 return 1;
 735         }
 736
 737         xdiff_clear_find_func(&xecfg);
 738         opt->priv = NULL;
 739
 740         /* NEEDSWORK:
 741          * The real "grep -c foo *.c" gives many "bar.c:0" lines,
 742          * which feels mostly useless but sometimes useful.  Maybe
 743          * make it another option?  For now suppress them.
 744          */
 745         if (opt->count && count)
 746                 printf("%s%c%u\n", name,
 747                        opt->null_following_name ? '\0' : ':', count);
 748         return !!last_hit;
 749 }
 750
 751 static void clr_hit_marker(struct grep_expr *x)
 752 {
 753         /* All-hit markers are meaningful only at the very top level
 754          * OR node.
 755          */
 756         while (1) {
 757                 x->hit = 0;
 758                 if (x->node != GREP_NODE_OR)
 759                         return;
 760                 x->u.binary.left->hit = 0;
 761                 x = x->u.binary.right;
 762         }
 763 }
 764
 765 static int chk_hit_marker(struct grep_expr *x)
 766 {
 767         /* Top level nodes have hit markers.  See if they all are hits */
 768         while (1) {
 769                 if (x->node != GREP_NODE_OR)
 770                         return x->hit;
 771                 if (!x->u.binary.left->hit)
 772                         return 0;
 773                 x = x->u.binary.right;
 774         }
 775 }
 776
 777 int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
 778 {
 779         /*
 780          * we do not have to do the two-pass grep when we do not check
 781          * buffer-wide "all-match".
 782          */
 783         if (!opt->all_match)
 784                 return grep_buffer_1(opt, name, buf, size, 0);
 785
 786         /* Otherwise the toplevel "or" terms hit a bit differently.
 787          * We first clear hit markers from them.
 788          */
 789         clr_hit_marker(opt->pattern_expression);
 790         grep_buffer_1(opt, name, buf, size, 1);
 791
 792         if (!chk_hit_marker(opt->pattern_expression))
 793                 return 0;
 794
 795         return grep_buffer_1(opt, name, buf, size, 0);
 796 }