Andrew's git - gitweb.git/blob

b95803bbb19a9094dae1d84b214ed04005ab9019
   1#include "cache.h"
   2#include "grep.h"
   3#include "userdiff.h"
   4#include "xdiff-interface.h"
   5
   6void 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->header_tail = p;
  15        opt->header_tail = &p->next;
  16        p->next = NULL;
  17}
  18
  19void 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
  32struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
  33{
  34        struct grep_pat *pat;
  35        struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
  36        *ret = *opt;
  37
  38        ret->pattern_list = NULL;
  39        ret->pattern_tail = &ret->pattern_list;
  40
  41        for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
  42        {
  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);
  49        }
  50
  51        return ret;
  52}
  53
  54static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
  55{
  56        int err;
  57
  58        p->word_regexp = opt->word_regexp;
  59        p->ignore_case = opt->ignore_case;
  60        p->fixed = opt->fixed;
  61
  62        if (p->fixed)
  63                return;
  64
  65        err = regcomp(&p->regexp, p->pattern, opt->regflags);
  66        if (err) {
  67                char errbuf[1024];
  68                char where[1024];
  69                if (p->no)
  70                        sprintf(where, "In '%s' at %d, ",
  71                                p->origin, p->no);
  72                else if (p->origin)
  73                        sprintf(where, "%s, ", p->origin);
  74                else
  75                        where[0] = 0;
  76                regerror(err, &p->regexp, errbuf, 1024);
  77                regfree(&p->regexp);
  78                die("%s'%s': %s", where, p->pattern, errbuf);
  79        }
  80}
  81
  82static struct grep_expr *compile_pattern_or(struct grep_pat **);
  83static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
  84{
  85        struct grep_pat *p;
  86        struct grep_expr *x;
  87
  88        p = *list;
  89        if (!p)
  90                return NULL;
  91        switch (p->token) {
  92        case GREP_PATTERN: /* atom */
  93        case GREP_PATTERN_HEAD:
  94        case GREP_PATTERN_BODY:
  95                x = xcalloc(1, sizeof (struct grep_expr));
  96                x->node = GREP_NODE_ATOM;
  97                x->u.atom = p;
  98                *list = p->next;
  99                return x;
 100        case GREP_OPEN_PAREN:
 101                *list = p->next;
 102                x = compile_pattern_or(list);
 103                if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 104                        die("unmatched parenthesis");
 105                *list = (*list)->next;
 106                return x;
 107        default:
 108                return NULL;
 109        }
 110}
 111
 112static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 113{
 114        struct grep_pat *p;
 115        struct grep_expr *x;
 116
 117        p = *list;
 118        if (!p)
 119                return NULL;
 120        switch (p->token) {
 121        case GREP_NOT:
 122                if (!p->next)
 123                        die("--not not followed by pattern expression");
 124                *list = p->next;
 125                x = xcalloc(1, sizeof (struct grep_expr));
 126                x->node = GREP_NODE_NOT;
 127                x->u.unary = compile_pattern_not(list);
 128                if (!x->u.unary)
 129                        die("--not followed by non pattern expression");
 130                return x;
 131        default:
 132                return compile_pattern_atom(list);
 133        }
 134}
 135
 136static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 137{
 138        struct grep_pat *p;
 139        struct grep_expr *x, *y, *z;
 140
 141        x = compile_pattern_not(list);
 142        p = *list;
 143        if (p && p->token == GREP_AND) {
 144                if (!p->next)
 145                        die("--and not followed by pattern expression");
 146                *list = p->next;
 147                y = compile_pattern_and(list);
 148                if (!y)
 149                        die("--and not followed by pattern expression");
 150                z = xcalloc(1, sizeof (struct grep_expr));
 151                z->node = GREP_NODE_AND;
 152                z->u.binary.left = x;
 153                z->u.binary.right = y;
 154                return z;
 155        }
 156        return x;
 157}
 158
 159static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 160{
 161        struct grep_pat *p;
 162        struct grep_expr *x, *y, *z;
 163
 164        x = compile_pattern_and(list);
 165        p = *list;
 166        if (x && p && p->token != GREP_CLOSE_PAREN) {
 167                y = compile_pattern_or(list);
 168                if (!y)
 169                        die("not a pattern expression %s", p->pattern);
 170                z = xcalloc(1, sizeof (struct grep_expr));
 171                z->node = GREP_NODE_OR;
 172                z->u.binary.left = x;
 173                z->u.binary.right = y;
 174                return z;
 175        }
 176        return x;
 177}
 178
 179static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 180{
 181        return compile_pattern_or(list);
 182}
 183
 184void compile_grep_patterns(struct grep_opt *opt)
 185{
 186        struct grep_pat *p;
 187        struct grep_expr *header_expr = NULL;
 188
 189        if (opt->header_list) {
 190                p = opt->header_list;
 191                header_expr = compile_pattern_expr(&p);
 192                if (p)
 193                        die("incomplete pattern expression: %s", p->pattern);
 194                for (p = opt->header_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;
 204                        }
 205                }
 206        }
 207
 208        for (p = opt->pattern_list; p; p = p->next) {
 209                switch (p->token) {
 210                case GREP_PATTERN: /* atom */
 211                case GREP_PATTERN_HEAD:
 212                case GREP_PATTERN_BODY:
 213                        compile_regexp(p, opt);
 214                        break;
 215                default:
 216                        opt->extended = 1;
 217                        break;
 218                }
 219        }
 220
 221        if (opt->all_match || header_expr)
 222                opt->extended = 1;
 223        else if (!opt->extended)
 224                return;
 225
 226        /* Then bundle them up in an expression.
 227         * A classic recursive descent parser would do.
 228         */
 229        p = opt->pattern_list;
 230        if (p)
 231                opt->pattern_expression = compile_pattern_expr(&p);
 232        if (p)
 233                die("incomplete pattern expression: %s", p->pattern);
 234
 235        if (!header_expr)
 236                return;
 237
 238        if (opt->pattern_expression) {
 239                struct grep_expr *z;
 240                z = xcalloc(1, sizeof(*z));
 241                z->node = GREP_NODE_OR;
 242                z->u.binary.left = opt->pattern_expression;
 243                z->u.binary.right = header_expr;
 244                opt->pattern_expression = z;
 245        } else {
 246                opt->pattern_expression = header_expr;
 247        }
 248        opt->all_match = 1;
 249}
 250
 251static void free_pattern_expr(struct grep_expr *x)
 252{
 253        switch (x->node) {
 254        case GREP_NODE_ATOM:
 255                break;
 256        case GREP_NODE_NOT:
 257                free_pattern_expr(x->u.unary);
 258                break;
 259        case GREP_NODE_AND:
 260        case GREP_NODE_OR:
 261                free_pattern_expr(x->u.binary.left);
 262                free_pattern_expr(x->u.binary.right);
 263                break;
 264        }
 265        free(x);
 266}
 267
 268void free_grep_patterns(struct grep_opt *opt)
 269{
 270        struct grep_pat *p, *n;
 271
 272        for (p = opt->pattern_list; p; p = n) {
 273                n = p->next;
 274                switch (p->token) {
 275                case GREP_PATTERN: /* atom */
 276                case GREP_PATTERN_HEAD:
 277                case GREP_PATTERN_BODY:
 278                        regfree(&p->regexp);
 279                        break;
 280                default:
 281                        break;
 282                }
 283                free(p);
 284        }
 285
 286        if (!opt->extended)
 287                return;
 288        free_pattern_expr(opt->pattern_expression);
 289}
 290
 291static char *end_of_line(char *cp, unsigned long *left)
 292{
 293        unsigned long l = *left;
 294        while (l && *cp != '\n') {
 295                l--;
 296                cp++;
 297        }
 298        *left = l;
 299        return cp;
 300}
 301
 302static int word_char(char ch)
 303{
 304        return isalnum(ch) || ch == '_';
 305}
 306
 307static void output_color(struct grep_opt *opt, const void *data, size_t size,
 308                         const char *color)
 309{
 310        if (opt->color && color && color[0]) {
 311                opt->output(opt, color, strlen(color));
 312                opt->output(opt, data, size);
 313                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
 314        } else
 315                opt->output(opt, data, size);
 316}
 317
 318static void output_sep(struct grep_opt *opt, char sign)
 319{
 320        if (opt->null_following_name)
 321                opt->output(opt, "\0", 1);
 322        else
 323                output_color(opt, &sign, 1, opt->color_sep);
 324}
 325
 326static void show_name(struct grep_opt *opt, const char *name)
 327{
 328        output_color(opt, name, strlen(name), opt->color_filename);
 329        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 330}
 331
 332static int fixmatch(const char *pattern, char *line, char *eol,
 333                    int ignore_case, regmatch_t *match)
 334{
 335        char *hit;
 336
 337        if (ignore_case) {
 338                char *s = line;
 339                do {
 340                        hit = strcasestr(s, pattern);
 341                        if (hit)
 342                                break;
 343                        s += strlen(s) + 1;
 344                } while (s < eol);
 345        } else
 346                hit = memmem(line, eol - line, pattern, strlen(pattern));
 347
 348        if (!hit) {
 349                match->rm_so = match->rm_eo = -1;
 350                return REG_NOMATCH;
 351        }
 352        else {
 353                match->rm_so = hit - line;
 354                match->rm_eo = match->rm_so + strlen(pattern);
 355                return 0;
 356        }
 357}
 358
 359static int strip_timestamp(char *bol, char **eol_p)
 360{
 361        char *eol = *eol_p;
 362        int ch;
 363
 364        while (bol < --eol) {
 365                if (*eol != '>')
 366                        continue;
 367                *eol_p = ++eol;
 368                ch = *eol;
 369                *eol = '\0';
 370                return ch;
 371        }
 372        return 0;
 373}
 374
 375static struct {
 376        const char *field;
 377        size_t len;
 378} header_field[] = {
 379        { "author ", 7 },
 380        { "committer ", 10 },
 381};
 382
 383static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 384                             enum grep_context ctx,
 385                             regmatch_t *pmatch, int eflags)
 386{
 387        int hit = 0;
 388        int saved_ch = 0;
 389        const char *start = bol;
 390
 391        if ((p->token != GREP_PATTERN) &&
 392            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 393                return 0;
 394
 395        if (p->token == GREP_PATTERN_HEAD) {
 396                const char *field;
 397                size_t len;
 398                assert(p->field < ARRAY_SIZE(header_field));
 399                field = header_field[p->field].field;
 400                len = header_field[p->field].len;
 401                if (strncmp(bol, field, len))
 402                        return 0;
 403                bol += len;
 404                saved_ch = strip_timestamp(bol, &eol);
 405        }
 406
 407 again:
 408        if (p->fixed)
 409                hit = !fixmatch(p->pattern, bol, eol, p->ignore_case, pmatch);
 410        else
 411                hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
 412
 413        if (hit && p->word_regexp) {
 414                if ((pmatch[0].rm_so < 0) ||
 415                    (eol - bol) < pmatch[0].rm_so ||
 416                    (pmatch[0].rm_eo < 0) ||
 417                    (eol - bol) < pmatch[0].rm_eo)
 418                        die("regexp returned nonsense");
 419
 420                /* Match beginning must be either beginning of the
 421                 * line, or at word boundary (i.e. the last char must
 422                 * not be a word char).  Similarly, match end must be
 423                 * either end of the line, or at word boundary
 424                 * (i.e. the next char must not be a word char).
 425                 */
 426                if ( ((pmatch[0].rm_so == 0) ||
 427                      !word_char(bol[pmatch[0].rm_so-1])) &&
 428                     ((pmatch[0].rm_eo == (eol-bol)) ||
 429                      !word_char(bol[pmatch[0].rm_eo])) )
 430                        ;
 431                else
 432                        hit = 0;
 433
 434                /* Words consist of at least one character. */
 435                if (pmatch->rm_so == pmatch->rm_eo)
 436                        hit = 0;
 437
 438                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 439                        /* There could be more than one match on the
 440                         * line, and the first match might not be
 441                         * strict word match.  But later ones could be!
 442                         * Forward to the next possible start, i.e. the
 443                         * next position following a non-word char.
 444                         */
 445                        bol = pmatch[0].rm_so + bol + 1;
 446                        while (word_char(bol[-1]) && bol < eol)
 447                                bol++;
 448                        eflags |= REG_NOTBOL;
 449                        if (bol < eol)
 450                                goto again;
 451                }
 452        }
 453        if (p->token == GREP_PATTERN_HEAD && saved_ch)
 454                *eol = saved_ch;
 455        if (hit) {
 456                pmatch[0].rm_so += bol - start;
 457                pmatch[0].rm_eo += bol - start;
 458        }
 459        return hit;
 460}
 461
 462static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 463                           enum grep_context ctx, int collect_hits)
 464{
 465        int h = 0;
 466        regmatch_t match;
 467
 468        if (!x)
 469                die("Not a valid grep expression");
 470        switch (x->node) {
 471        case GREP_NODE_ATOM:
 472                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 473                break;
 474        case GREP_NODE_NOT:
 475                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 476                break;
 477        case GREP_NODE_AND:
 478                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 479                        return 0;
 480                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 481                break;
 482        case GREP_NODE_OR:
 483                if (!collect_hits)
 484                        return (match_expr_eval(x->u.binary.left,
 485                                                bol, eol, ctx, 0) ||
 486                                match_expr_eval(x->u.binary.right,
 487                                                bol, eol, ctx, 0));
 488                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 489                x->u.binary.left->hit |= h;
 490                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 491                break;
 492        default:
 493                die("Unexpected node type (internal error) %d", x->node);
 494        }
 495        if (collect_hits)
 496                x->hit |= h;
 497        return h;
 498}
 499
 500static int match_expr(struct grep_opt *opt, char *bol, char *eol,
 501                      enum grep_context ctx, int collect_hits)
 502{
 503        struct grep_expr *x = opt->pattern_expression;
 504        return match_expr_eval(x, bol, eol, ctx, collect_hits);
 505}
 506
 507static int match_line(struct grep_opt *opt, char *bol, char *eol,
 508                      enum grep_context ctx, int collect_hits)
 509{
 510        struct grep_pat *p;
 511        regmatch_t match;
 512
 513        if (opt->extended)
 514                return match_expr(opt, bol, eol, ctx, collect_hits);
 515
 516        /* we do not call with collect_hits without being extended */
 517        for (p = opt->pattern_list; p; p = p->next) {
 518                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
 519                        return 1;
 520        }
 521        return 0;
 522}
 523
 524static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
 525                              enum grep_context ctx,
 526                              regmatch_t *pmatch, int eflags)
 527{
 528        regmatch_t match;
 529
 530        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
 531                return 0;
 532        if (match.rm_so < 0 || match.rm_eo < 0)
 533                return 0;
 534        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
 535                if (match.rm_so > pmatch->rm_so)
 536                        return 1;
 537                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
 538                        return 1;
 539        }
 540        pmatch->rm_so = match.rm_so;
 541        pmatch->rm_eo = match.rm_eo;
 542        return 1;
 543}
 544
 545static int next_match(struct grep_opt *opt, char *bol, char *eol,
 546                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
 547{
 548        struct grep_pat *p;
 549        int hit = 0;
 550
 551        pmatch->rm_so = pmatch->rm_eo = -1;
 552        if (bol < eol) {
 553                for (p = opt->pattern_list; p; p = p->next) {
 554                        switch (p->token) {
 555                        case GREP_PATTERN: /* atom */
 556                        case GREP_PATTERN_HEAD:
 557                        case GREP_PATTERN_BODY:
 558                                hit |= match_next_pattern(p, bol, eol, ctx,
 559                                                          pmatch, eflags);
 560                                break;
 561                        default:
 562                                break;
 563                        }
 564                }
 565        }
 566        return hit;
 567}
 568
 569static void show_line(struct grep_opt *opt, char *bol, char *eol,
 570                      const char *name, unsigned lno, char sign)
 571{
 572        int rest = eol - bol;
 573        char *line_color = NULL;
 574
 575        if (opt->pre_context || opt->post_context) {
 576                if (opt->last_shown == 0) {
 577                        if (opt->show_hunk_mark) {
 578                                output_color(opt, "--", 2, opt->color_sep);
 579                                opt->output(opt, "\n", 1);
 580                        }
 581                } else if (lno > opt->last_shown + 1) {
 582                        output_color(opt, "--", 2, opt->color_sep);
 583                        opt->output(opt, "\n", 1);
 584                }
 585        }
 586        opt->last_shown = lno;
 587
 588        if (opt->pathname) {
 589                output_color(opt, name, strlen(name), opt->color_filename);
 590                output_sep(opt, sign);
 591        }
 592        if (opt->linenum) {
 593                char buf[32];
 594                snprintf(buf, sizeof(buf), "%d", lno);
 595                output_color(opt, buf, strlen(buf), opt->color_lineno);
 596                output_sep(opt, sign);
 597        }
 598        if (opt->color) {
 599                regmatch_t match;
 600                enum grep_context ctx = GREP_CONTEXT_BODY;
 601                int ch = *eol;
 602                int eflags = 0;
 603
 604                if (sign == ':')
 605                        line_color = opt->color_selected;
 606                else if (sign == '-')
 607                        line_color = opt->color_context;
 608                else if (sign == '=')
 609                        line_color = opt->color_function;
 610                *eol = '\0';
 611                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
 612                        if (match.rm_so == match.rm_eo)
 613                                break;
 614
 615                        output_color(opt, bol, match.rm_so, line_color);
 616                        output_color(opt, bol + match.rm_so,
 617                                     match.rm_eo - match.rm_so,
 618                                     opt->color_match);
 619                        bol += match.rm_eo;
 620                        rest -= match.rm_eo;
 621                        eflags = REG_NOTBOL;
 622                }
 623                *eol = ch;
 624        }
 625        output_color(opt, bol, rest, line_color);
 626        opt->output(opt, "\n", 1);
 627}
 628
 629static int match_funcname(struct grep_opt *opt, char *bol, char *eol)
 630{
 631        xdemitconf_t *xecfg = opt->priv;
 632        if (xecfg && xecfg->find_func) {
 633                char buf[1];
 634                return xecfg->find_func(bol, eol - bol, buf, 1,
 635                                        xecfg->find_func_priv) >= 0;
 636        }
 637
 638        if (bol == eol)
 639                return 0;
 640        if (isalpha(*bol) || *bol == '_' || *bol == '$')
 641                return 1;
 642        return 0;
 643}
 644
 645static void show_funcname_line(struct grep_opt *opt, const char *name,
 646                               char *buf, char *bol, unsigned lno)
 647{
 648        while (bol > buf) {
 649                char *eol = --bol;
 650
 651                while (bol > buf && bol[-1] != '\n')
 652                        bol--;
 653                lno--;
 654
 655                if (lno <= opt->last_shown)
 656                        break;
 657
 658                if (match_funcname(opt, bol, eol)) {
 659                        show_line(opt, bol, eol, name, lno, '=');
 660                        break;
 661                }
 662        }
 663}
 664
 665static void show_pre_context(struct grep_opt *opt, const char *name, char *buf,
 666                             char *bol, unsigned lno)
 667{
 668        unsigned cur = lno, from = 1, funcname_lno = 0;
 669        int funcname_needed = opt->funcname;
 670
 671        if (opt->pre_context < lno)
 672                from = lno - opt->pre_context;
 673        if (from <= opt->last_shown)
 674                from = opt->last_shown + 1;
 675
 676        /* Rewind. */
 677        while (bol > buf && cur > from) {
 678                char *eol = --bol;
 679
 680                while (bol > buf && bol[-1] != '\n')
 681                        bol--;
 682                cur--;
 683                if (funcname_needed && match_funcname(opt, bol, eol)) {
 684                        funcname_lno = cur;
 685                        funcname_needed = 0;
 686                }
 687        }
 688
 689        /* We need to look even further back to find a function signature. */
 690        if (opt->funcname && funcname_needed)
 691                show_funcname_line(opt, name, buf, bol, cur);
 692
 693        /* Back forward. */
 694        while (cur < lno) {
 695                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
 696
 697                while (*eol != '\n')
 698                        eol++;
 699                show_line(opt, bol, eol, name, cur, sign);
 700                bol = eol + 1;
 701                cur++;
 702        }
 703}
 704
 705static int should_lookahead(struct grep_opt *opt)
 706{
 707        struct grep_pat *p;
 708
 709        if (opt->extended)
 710                return 0; /* punt for too complex stuff */
 711        if (opt->invert)
 712                return 0;
 713        for (p = opt->pattern_list; p; p = p->next) {
 714                if (p->token != GREP_PATTERN)
 715                        return 0; /* punt for "header only" and stuff */
 716        }
 717        return 1;
 718}
 719
 720static int look_ahead(struct grep_opt *opt,
 721                      unsigned long *left_p,
 722                      unsigned *lno_p,
 723                      char **bol_p)
 724{
 725        unsigned lno = *lno_p;
 726        char *bol = *bol_p;
 727        struct grep_pat *p;
 728        char *sp, *last_bol;
 729        regoff_t earliest = -1;
 730
 731        for (p = opt->pattern_list; p; p = p->next) {
 732                int hit;
 733                regmatch_t m;
 734
 735                if (p->fixed) {
 736                        hit = !fixmatch(p->pattern, bol, bol + *left_p,
 737                                        p->ignore_case, &m);
 738                } else {
 739#ifdef REG_STARTEND
 740                        m.rm_so = 0;
 741                        m.rm_eo = *left_p;
 742                        hit = !regexec(&p->regexp, bol, 1, &m, REG_STARTEND);
 743#else
 744                        hit = !regexec(&p->regexp, bol, 1, &m, 0);
 745#endif
 746                }
 747                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
 748                        continue;
 749                if (earliest < 0 || m.rm_so < earliest)
 750                        earliest = m.rm_so;
 751        }
 752
 753        if (earliest < 0) {
 754                *bol_p = bol + *left_p;
 755                *left_p = 0;
 756                return 1;
 757        }
 758        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
 759                ; /* find the beginning of the line */
 760        last_bol = sp;
 761
 762        for (sp = bol; sp < last_bol; sp++) {
 763                if (*sp == '\n')
 764                        lno++;
 765        }
 766        *left_p -= last_bol - bol;
 767        *bol_p = last_bol;
 768        *lno_p = lno;
 769        return 0;
 770}
 771
 772int grep_threads_ok(const struct grep_opt *opt)
 773{
 774        /* If this condition is true, then we may use the attribute
 775         * machinery in grep_buffer_1. The attribute code is not
 776         * thread safe, so we disable the use of threads.
 777         */
 778        if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
 779            !opt->name_only)
 780                return 0;
 781
 782        return 1;
 783}
 784
 785static void std_output(struct grep_opt *opt, const void *buf, size_t size)
 786{
 787        fwrite(buf, size, 1, stdout);
 788}
 789
 790static int grep_buffer_1(struct grep_opt *opt, const char *name,
 791                         char *buf, unsigned long size, int collect_hits)
 792{
 793        char *bol = buf;
 794        unsigned long left = size;
 795        unsigned lno = 1;
 796        unsigned last_hit = 0;
 797        int binary_match_only = 0;
 798        unsigned count = 0;
 799        int try_lookahead = 0;
 800        enum grep_context ctx = GREP_CONTEXT_HEAD;
 801        xdemitconf_t xecfg;
 802
 803        if (!opt->output)
 804                opt->output = std_output;
 805
 806        if (opt->last_shown && (opt->pre_context || opt->post_context) &&
 807            opt->output == std_output)
 808                opt->show_hunk_mark = 1;
 809        opt->last_shown = 0;
 810
 811        switch (opt->binary) {
 812        case GREP_BINARY_DEFAULT:
 813                if (buffer_is_binary(buf, size))
 814                        binary_match_only = 1;
 815                break;
 816        case GREP_BINARY_NOMATCH:
 817                if (buffer_is_binary(buf, size))
 818                        return 0; /* Assume unmatch */
 819                break;
 820        case GREP_BINARY_TEXT:
 821                break;
 822        default:
 823                die("bug: unknown binary handling mode");
 824        }
 825
 826        memset(&xecfg, 0, sizeof(xecfg));
 827        if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
 828            !opt->name_only && !binary_match_only && !collect_hits) {
 829                struct userdiff_driver *drv = userdiff_find_by_path(name);
 830                if (drv && drv->funcname.pattern) {
 831                        const struct userdiff_funcname *pe = &drv->funcname;
 832                        xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
 833                        opt->priv = &xecfg;
 834                }
 835        }
 836        try_lookahead = should_lookahead(opt);
 837
 838        while (left) {
 839                char *eol, ch;
 840                int hit;
 841
 842                /*
 843                 * look_ahead() skips quicly to the line that possibly
 844                 * has the next hit; don't call it if we need to do
 845                 * something more than just skipping the current line
 846                 * in response to an unmatch for the current line.  E.g.
 847                 * inside a post-context window, we will show the current
 848                 * line as a context around the previous hit when it
 849                 * doesn't hit.
 850                 */
 851                if (try_lookahead
 852                    && !(last_hit
 853                         && lno <= last_hit + opt->post_context)
 854                    && look_ahead(opt, &left, &lno, &bol))
 855                        break;
 856                eol = end_of_line(bol, &left);
 857                ch = *eol;
 858                *eol = 0;
 859
 860                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
 861                        ctx = GREP_CONTEXT_BODY;
 862
 863                hit = match_line(opt, bol, eol, ctx, collect_hits);
 864                *eol = ch;
 865
 866                if (collect_hits)
 867                        goto next_line;
 868
 869                /* "grep -v -e foo -e bla" should list lines
 870                 * that do not have either, so inversion should
 871                 * be done outside.
 872                 */
 873                if (opt->invert)
 874                        hit = !hit;
 875                if (opt->unmatch_name_only) {
 876                        if (hit)
 877                                return 0;
 878                        goto next_line;
 879                }
 880                if (hit) {
 881                        count++;
 882                        if (opt->status_only)
 883                                return 1;
 884                        if (opt->name_only) {
 885                                show_name(opt, name);
 886                                return 1;
 887                        }
 888                        if (opt->count)
 889                                goto next_line;
 890                        if (binary_match_only) {
 891                                opt->output(opt, "Binary file ", 12);
 892                                output_color(opt, name, strlen(name),
 893                                             opt->color_filename);
 894                                opt->output(opt, " matches\n", 9);
 895                                return 1;
 896                        }
 897                        /* Hit at this line.  If we haven't shown the
 898                         * pre-context lines, we would need to show them.
 899                         */
 900                        if (opt->pre_context)
 901                                show_pre_context(opt, name, buf, bol, lno);
 902                        else if (opt->funcname)
 903                                show_funcname_line(opt, name, buf, bol, lno);
 904                        show_line(opt, bol, eol, name, lno, ':');
 905                        last_hit = lno;
 906                }
 907                else if (last_hit &&
 908                         lno <= last_hit + opt->post_context) {
 909                        /* If the last hit is within the post context,
 910                         * we need to show this line.
 911                         */
 912                        show_line(opt, bol, eol, name, lno, '-');
 913                }
 914
 915        next_line:
 916                bol = eol + 1;
 917                if (!left)
 918                        break;
 919                left--;
 920                lno++;
 921        }
 922
 923        if (collect_hits)
 924                return 0;
 925
 926        if (opt->status_only)
 927                return 0;
 928        if (opt->unmatch_name_only) {
 929                /* We did not see any hit, so we want to show this */
 930                show_name(opt, name);
 931                return 1;
 932        }
 933
 934        xdiff_clear_find_func(&xecfg);
 935        opt->priv = NULL;
 936
 937        /* NEEDSWORK:
 938         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
 939         * which feels mostly useless but sometimes useful.  Maybe
 940         * make it another option?  For now suppress them.
 941         */
 942        if (opt->count && count) {
 943                char buf[32];
 944                output_color(opt, name, strlen(name), opt->color_filename);
 945                output_sep(opt, ':');
 946                snprintf(buf, sizeof(buf), "%u\n", count);
 947                opt->output(opt, buf, strlen(buf));
 948                return 1;
 949        }
 950        return !!last_hit;
 951}
 952
 953static void clr_hit_marker(struct grep_expr *x)
 954{
 955        /* All-hit markers are meaningful only at the very top level
 956         * OR node.
 957         */
 958        while (1) {
 959                x->hit = 0;
 960                if (x->node != GREP_NODE_OR)
 961                        return;
 962                x->u.binary.left->hit = 0;
 963                x = x->u.binary.right;
 964        }
 965}
 966
 967static int chk_hit_marker(struct grep_expr *x)
 968{
 969        /* Top level nodes have hit markers.  See if they all are hits */
 970        while (1) {
 971                if (x->node != GREP_NODE_OR)
 972                        return x->hit;
 973                if (!x->u.binary.left->hit)
 974                        return 0;
 975                x = x->u.binary.right;
 976        }
 977}
 978
 979int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
 980{
 981        /*
 982         * we do not have to do the two-pass grep when we do not check
 983         * buffer-wide "all-match".
 984         */
 985        if (!opt->all_match)
 986                return grep_buffer_1(opt, name, buf, size, 0);
 987
 988        /* Otherwise the toplevel "or" terms hit a bit differently.
 989         * We first clear hit markers from them.
 990         */
 991        clr_hit_marker(opt->pattern_expression);
 992        grep_buffer_1(opt, name, buf, size, 1);
 993
 994        if (!chk_hit_marker(opt->pattern_expression))
 995                return 0;
 996
 997        return grep_buffer_1(opt, name, buf, size, 0);
 998}