817270d0819b6b0c3a474941a66af07dcb9c68d3
   1#include "cache.h"
   2#include "config.h"
   3#include "grep.h"
   4#include "userdiff.h"
   5#include "xdiff-interface.h"
   6#include "diff.h"
   7#include "diffcore.h"
   8#include "commit.h"
   9#include "quote.h"
  10
  11static int grep_source_load(struct grep_source *gs);
  12static int grep_source_is_binary(struct grep_source *gs);
  13
  14static struct grep_opt grep_defaults;
  15
  16static void std_output(struct grep_opt *opt, const void *buf, size_t size)
  17{
  18        fwrite(buf, size, 1, stdout);
  19}
  20
  21/*
  22 * Initialize the grep_defaults template with hardcoded defaults.
  23 * We could let the compiler do this, but without C99 initializers
  24 * the code gets unwieldy and unreadable, so...
  25 */
  26void init_grep_defaults(void)
  27{
  28        struct grep_opt *opt = &grep_defaults;
  29        static int run_once;
  30
  31        if (run_once)
  32                return;
  33        run_once++;
  34
  35        memset(opt, 0, sizeof(*opt));
  36        opt->relative = 1;
  37        opt->pathname = 1;
  38        opt->regflags = REG_NEWLINE;
  39        opt->max_depth = -1;
  40        opt->pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED;
  41        color_set(opt->color_context, "");
  42        color_set(opt->color_filename, "");
  43        color_set(opt->color_function, "");
  44        color_set(opt->color_lineno, "");
  45        color_set(opt->color_match_context, GIT_COLOR_BOLD_RED);
  46        color_set(opt->color_match_selected, GIT_COLOR_BOLD_RED);
  47        color_set(opt->color_selected, "");
  48        color_set(opt->color_sep, GIT_COLOR_CYAN);
  49        opt->color = -1;
  50        opt->output = std_output;
  51}
  52
  53static int parse_pattern_type_arg(const char *opt, const char *arg)
  54{
  55        if (!strcmp(arg, "default"))
  56                return GREP_PATTERN_TYPE_UNSPECIFIED;
  57        else if (!strcmp(arg, "basic"))
  58                return GREP_PATTERN_TYPE_BRE;
  59        else if (!strcmp(arg, "extended"))
  60                return GREP_PATTERN_TYPE_ERE;
  61        else if (!strcmp(arg, "fixed"))
  62                return GREP_PATTERN_TYPE_FIXED;
  63        else if (!strcmp(arg, "perl"))
  64                return GREP_PATTERN_TYPE_PCRE;
  65        die("bad %s argument: %s", opt, arg);
  66}
  67
  68/*
  69 * Read the configuration file once and store it in
  70 * the grep_defaults template.
  71 */
  72int grep_config(const char *var, const char *value, void *cb)
  73{
  74        struct grep_opt *opt = &grep_defaults;
  75        char *color = NULL;
  76
  77        if (userdiff_config(var, value) < 0)
  78                return -1;
  79
  80        if (!strcmp(var, "grep.extendedregexp")) {
  81                opt->extended_regexp_option = git_config_bool(var, value);
  82                return 0;
  83        }
  84
  85        if (!strcmp(var, "grep.patterntype")) {
  86                opt->pattern_type_option = parse_pattern_type_arg(var, value);
  87                return 0;
  88        }
  89
  90        if (!strcmp(var, "grep.linenumber")) {
  91                opt->linenum = git_config_bool(var, value);
  92                return 0;
  93        }
  94
  95        if (!strcmp(var, "grep.fullname")) {
  96                opt->relative = !git_config_bool(var, value);
  97                return 0;
  98        }
  99
 100        if (!strcmp(var, "color.grep"))
 101                opt->color = git_config_colorbool(var, value);
 102        else if (!strcmp(var, "color.grep.context"))
 103                color = opt->color_context;
 104        else if (!strcmp(var, "color.grep.filename"))
 105                color = opt->color_filename;
 106        else if (!strcmp(var, "color.grep.function"))
 107                color = opt->color_function;
 108        else if (!strcmp(var, "color.grep.linenumber"))
 109                color = opt->color_lineno;
 110        else if (!strcmp(var, "color.grep.matchcontext"))
 111                color = opt->color_match_context;
 112        else if (!strcmp(var, "color.grep.matchselected"))
 113                color = opt->color_match_selected;
 114        else if (!strcmp(var, "color.grep.selected"))
 115                color = opt->color_selected;
 116        else if (!strcmp(var, "color.grep.separator"))
 117                color = opt->color_sep;
 118        else if (!strcmp(var, "color.grep.match")) {
 119                int rc = 0;
 120                if (!value)
 121                        return config_error_nonbool(var);
 122                rc |= color_parse(value, opt->color_match_context);
 123                rc |= color_parse(value, opt->color_match_selected);
 124                return rc;
 125        }
 126
 127        if (color) {
 128                if (!value)
 129                        return config_error_nonbool(var);
 130                return color_parse(value, color);
 131        }
 132        return 0;
 133}
 134
 135/*
 136 * Initialize one instance of grep_opt and copy the
 137 * default values from the template we read the configuration
 138 * information in an earlier call to git_config(grep_config).
 139 */
 140void grep_init(struct grep_opt *opt, const char *prefix)
 141{
 142        struct grep_opt *def = &grep_defaults;
 143
 144        memset(opt, 0, sizeof(*opt));
 145        opt->prefix = prefix;
 146        opt->prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 147        opt->pattern_tail = &opt->pattern_list;
 148        opt->header_tail = &opt->header_list;
 149
 150        opt->color = def->color;
 151        opt->extended_regexp_option = def->extended_regexp_option;
 152        opt->pattern_type_option = def->pattern_type_option;
 153        opt->linenum = def->linenum;
 154        opt->max_depth = def->max_depth;
 155        opt->pathname = def->pathname;
 156        opt->regflags = def->regflags;
 157        opt->relative = def->relative;
 158        opt->output = def->output;
 159
 160        color_set(opt->color_context, def->color_context);
 161        color_set(opt->color_filename, def->color_filename);
 162        color_set(opt->color_function, def->color_function);
 163        color_set(opt->color_lineno, def->color_lineno);
 164        color_set(opt->color_match_context, def->color_match_context);
 165        color_set(opt->color_match_selected, def->color_match_selected);
 166        color_set(opt->color_selected, def->color_selected);
 167        color_set(opt->color_sep, def->color_sep);
 168}
 169
 170static void grep_set_pattern_type_option(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 171{
 172        switch (pattern_type) {
 173        case GREP_PATTERN_TYPE_UNSPECIFIED:
 174                /* fall through */
 175
 176        case GREP_PATTERN_TYPE_BRE:
 177                opt->fixed = 0;
 178                opt->pcre1 = 0;
 179                opt->pcre2 = 0;
 180                break;
 181
 182        case GREP_PATTERN_TYPE_ERE:
 183                opt->fixed = 0;
 184                opt->pcre1 = 0;
 185                opt->pcre2 = 0;
 186                opt->regflags |= REG_EXTENDED;
 187                break;
 188
 189        case GREP_PATTERN_TYPE_FIXED:
 190                opt->fixed = 1;
 191                opt->pcre1 = 0;
 192                opt->pcre2 = 0;
 193                break;
 194
 195        case GREP_PATTERN_TYPE_PCRE:
 196                opt->fixed = 0;
 197#ifdef USE_LIBPCRE2
 198                opt->pcre1 = 0;
 199                opt->pcre2 = 1;
 200#else
 201                /*
 202                 * It's important that pcre1 always be assigned to
 203                 * even when there's no USE_LIBPCRE* defined. We still
 204                 * call the PCRE stub function, it just dies with
 205                 * "cannot use Perl-compatible regexes[...]".
 206                 */
 207                opt->pcre1 = 1;
 208                opt->pcre2 = 0;
 209#endif
 210                break;
 211        }
 212}
 213
 214void grep_commit_pattern_type(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 215{
 216        if (pattern_type != GREP_PATTERN_TYPE_UNSPECIFIED)
 217                grep_set_pattern_type_option(pattern_type, opt);
 218        else if (opt->pattern_type_option != GREP_PATTERN_TYPE_UNSPECIFIED)
 219                grep_set_pattern_type_option(opt->pattern_type_option, opt);
 220        else if (opt->extended_regexp_option)
 221                grep_set_pattern_type_option(GREP_PATTERN_TYPE_ERE, opt);
 222}
 223
 224static struct grep_pat *create_grep_pat(const char *pat, size_t patlen,
 225                                        const char *origin, int no,
 226                                        enum grep_pat_token t,
 227                                        enum grep_header_field field)
 228{
 229        struct grep_pat *p = xcalloc(1, sizeof(*p));
 230        p->pattern = xmemdupz(pat, patlen);
 231        p->patternlen = patlen;
 232        p->origin = origin;
 233        p->no = no;
 234        p->token = t;
 235        p->field = field;
 236        return p;
 237}
 238
 239static void do_append_grep_pat(struct grep_pat ***tail, struct grep_pat *p)
 240{
 241        **tail = p;
 242        *tail = &p->next;
 243        p->next = NULL;
 244
 245        switch (p->token) {
 246        case GREP_PATTERN: /* atom */
 247        case GREP_PATTERN_HEAD:
 248        case GREP_PATTERN_BODY:
 249                for (;;) {
 250                        struct grep_pat *new_pat;
 251                        size_t len = 0;
 252                        char *cp = p->pattern + p->patternlen, *nl = NULL;
 253                        while (++len <= p->patternlen) {
 254                                if (*(--cp) == '\n') {
 255                                        nl = cp;
 256                                        break;
 257                                }
 258                        }
 259                        if (!nl)
 260                                break;
 261                        new_pat = create_grep_pat(nl + 1, len - 1, p->origin,
 262                                                  p->no, p->token, p->field);
 263                        new_pat->next = p->next;
 264                        if (!p->next)
 265                                *tail = &new_pat->next;
 266                        p->next = new_pat;
 267                        *nl = '\0';
 268                        p->patternlen -= len;
 269                }
 270                break;
 271        default:
 272                break;
 273        }
 274}
 275
 276void append_header_grep_pattern(struct grep_opt *opt,
 277                                enum grep_header_field field, const char *pat)
 278{
 279        struct grep_pat *p = create_grep_pat(pat, strlen(pat), "header", 0,
 280                                             GREP_PATTERN_HEAD, field);
 281        if (field == GREP_HEADER_REFLOG)
 282                opt->use_reflog_filter = 1;
 283        do_append_grep_pat(&opt->header_tail, p);
 284}
 285
 286void append_grep_pattern(struct grep_opt *opt, const char *pat,
 287                         const char *origin, int no, enum grep_pat_token t)
 288{
 289        append_grep_pat(opt, pat, strlen(pat), origin, no, t);
 290}
 291
 292void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
 293                     const char *origin, int no, enum grep_pat_token t)
 294{
 295        struct grep_pat *p = create_grep_pat(pat, patlen, origin, no, t, 0);
 296        do_append_grep_pat(&opt->pattern_tail, p);
 297}
 298
 299struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
 300{
 301        struct grep_pat *pat;
 302        struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
 303        *ret = *opt;
 304
 305        ret->pattern_list = NULL;
 306        ret->pattern_tail = &ret->pattern_list;
 307
 308        for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
 309        {
 310                if(pat->token == GREP_PATTERN_HEAD)
 311                        append_header_grep_pattern(ret, pat->field,
 312                                                   pat->pattern);
 313                else
 314                        append_grep_pat(ret, pat->pattern, pat->patternlen,
 315                                        pat->origin, pat->no, pat->token);
 316        }
 317
 318        return ret;
 319}
 320
 321static NORETURN void compile_regexp_failed(const struct grep_pat *p,
 322                const char *error)
 323{
 324        char where[1024];
 325
 326        if (p->no)
 327                xsnprintf(where, sizeof(where), "In '%s' at %d, ", p->origin, p->no);
 328        else if (p->origin)
 329                xsnprintf(where, sizeof(where), "%s, ", p->origin);
 330        else
 331                where[0] = 0;
 332
 333        die("%s'%s': %s", where, p->pattern, error);
 334}
 335
 336static int is_fixed(const char *s, size_t len)
 337{
 338        size_t i;
 339
 340        for (i = 0; i < len; i++) {
 341                if (is_regex_special(s[i]))
 342                        return 0;
 343        }
 344
 345        return 1;
 346}
 347
 348static int has_null(const char *s, size_t len)
 349{
 350        /*
 351         * regcomp cannot accept patterns with NULs so when using it
 352         * we consider any pattern containing a NUL fixed.
 353         */
 354        if (memchr(s, 0, len))
 355                return 1;
 356
 357        return 0;
 358}
 359
 360#ifdef USE_LIBPCRE1
 361static void compile_pcre1_regexp(struct grep_pat *p, const struct grep_opt *opt)
 362{
 363        const char *error;
 364        int erroffset;
 365        int options = PCRE_MULTILINE;
 366
 367        if (opt->ignore_case) {
 368                if (has_non_ascii(p->pattern))
 369                        p->pcre1_tables = pcre_maketables();
 370                options |= PCRE_CASELESS;
 371        }
 372        if (is_utf8_locale() && has_non_ascii(p->pattern))
 373                options |= PCRE_UTF8;
 374
 375        p->pcre1_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
 376                                      p->pcre1_tables);
 377        if (!p->pcre1_regexp)
 378                compile_regexp_failed(p, error);
 379
 380        p->pcre1_extra_info = pcre_study(p->pcre1_regexp, PCRE_STUDY_JIT_COMPILE, &error);
 381        if (!p->pcre1_extra_info && error)
 382                die("%s", error);
 383
 384#ifdef GIT_PCRE1_USE_JIT
 385        pcre_config(PCRE_CONFIG_JIT, &p->pcre1_jit_on);
 386        if (p->pcre1_jit_on == 1) {
 387                p->pcre1_jit_stack = pcre_jit_stack_alloc(1, 1024 * 1024);
 388                if (!p->pcre1_jit_stack)
 389                        die("Couldn't allocate PCRE JIT stack");
 390                pcre_assign_jit_stack(p->pcre1_extra_info, NULL, p->pcre1_jit_stack);
 391        } else if (p->pcre1_jit_on != 0) {
 392                die("BUG: The pcre1_jit_on variable should be 0 or 1, not %d",
 393                    p->pcre1_jit_on);
 394        }
 395#endif
 396}
 397
 398static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 399                regmatch_t *match, int eflags)
 400{
 401        int ovector[30], ret, flags = 0;
 402
 403        if (eflags & REG_NOTBOL)
 404                flags |= PCRE_NOTBOL;
 405
 406#ifdef GIT_PCRE1_USE_JIT
 407        if (p->pcre1_jit_on) {
 408                ret = pcre_jit_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
 409                                    eol - line, 0, flags, ovector,
 410                                    ARRAY_SIZE(ovector), p->pcre1_jit_stack);
 411        } else
 412#endif
 413        {
 414                ret = pcre_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
 415                                eol - line, 0, flags, ovector,
 416                                ARRAY_SIZE(ovector));
 417        }
 418
 419        if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 420                die("pcre_exec failed with error code %d", ret);
 421        if (ret > 0) {
 422                ret = 0;
 423                match->rm_so = ovector[0];
 424                match->rm_eo = ovector[1];
 425        }
 426
 427        return ret;
 428}
 429
 430static void free_pcre1_regexp(struct grep_pat *p)
 431{
 432        pcre_free(p->pcre1_regexp);
 433#ifdef GIT_PCRE1_USE_JIT
 434        if (p->pcre1_jit_on) {
 435                pcre_free_study(p->pcre1_extra_info);
 436                pcre_jit_stack_free(p->pcre1_jit_stack);
 437        } else
 438#endif
 439        {
 440                pcre_free(p->pcre1_extra_info);
 441        }
 442        pcre_free((void *)p->pcre1_tables);
 443}
 444#else /* !USE_LIBPCRE1 */
 445static void compile_pcre1_regexp(struct grep_pat *p, const struct grep_opt *opt)
 446{
 447        die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 448}
 449
 450static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 451                regmatch_t *match, int eflags)
 452{
 453        return 1;
 454}
 455
 456static void free_pcre1_regexp(struct grep_pat *p)
 457{
 458}
 459#endif /* !USE_LIBPCRE1 */
 460
 461#ifdef USE_LIBPCRE2
 462static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
 463{
 464        int error;
 465        PCRE2_UCHAR errbuf[256];
 466        PCRE2_SIZE erroffset;
 467        int options = PCRE2_MULTILINE;
 468        const uint8_t *character_tables = NULL;
 469        int jitret;
 470
 471        assert(opt->pcre2);
 472
 473        p->pcre2_compile_context = NULL;
 474
 475        if (opt->ignore_case) {
 476                if (has_non_ascii(p->pattern)) {
 477                        character_tables = pcre2_maketables(NULL);
 478                        p->pcre2_compile_context = pcre2_compile_context_create(NULL);
 479                        pcre2_set_character_tables(p->pcre2_compile_context, character_tables);
 480                }
 481                options |= PCRE2_CASELESS;
 482        }
 483        if (is_utf8_locale() && has_non_ascii(p->pattern))
 484                options |= PCRE2_UTF;
 485
 486        p->pcre2_pattern = pcre2_compile((PCRE2_SPTR)p->pattern,
 487                                         p->patternlen, options, &error, &erroffset,
 488                                         p->pcre2_compile_context);
 489
 490        if (p->pcre2_pattern) {
 491                p->pcre2_match_data = pcre2_match_data_create_from_pattern(p->pcre2_pattern, NULL);
 492                if (!p->pcre2_match_data)
 493                        die("Couldn't allocate PCRE2 match data");
 494        } else {
 495                pcre2_get_error_message(error, errbuf, sizeof(errbuf));
 496                compile_regexp_failed(p, (const char *)&errbuf);
 497        }
 498
 499        pcre2_config(PCRE2_CONFIG_JIT, &p->pcre2_jit_on);
 500        if (p->pcre2_jit_on == 1) {
 501                jitret = pcre2_jit_compile(p->pcre2_pattern, PCRE2_JIT_COMPLETE);
 502                if (jitret)
 503                        die("Couldn't JIT the PCRE2 pattern '%s', got '%d'\n", p->pattern, jitret);
 504                p->pcre2_jit_stack = pcre2_jit_stack_create(1, 1024 * 1024, NULL);
 505                if (!p->pcre2_jit_stack)
 506                        die("Couldn't allocate PCRE2 JIT stack");
 507                p->pcre2_match_context = pcre2_match_context_create(NULL);
 508                if (!p->pcre2_match_context)
 509                        die("Couldn't allocate PCRE2 match context");
 510                pcre2_jit_stack_assign(p->pcre2_match_context, NULL, p->pcre2_jit_stack);
 511        } else if (p->pcre2_jit_on != 0) {
 512                die("BUG: The pcre2_jit_on variable should be 0 or 1, not %d",
 513                    p->pcre1_jit_on);
 514        }
 515}
 516
 517static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
 518                regmatch_t *match, int eflags)
 519{
 520        int ret, flags = 0;
 521        PCRE2_SIZE *ovector;
 522        PCRE2_UCHAR errbuf[256];
 523
 524        if (eflags & REG_NOTBOL)
 525                flags |= PCRE2_NOTBOL;
 526
 527        if (p->pcre2_jit_on)
 528                ret = pcre2_jit_match(p->pcre2_pattern, (unsigned char *)line,
 529                                      eol - line, 0, flags, p->pcre2_match_data,
 530                                      NULL);
 531        else
 532                ret = pcre2_match(p->pcre2_pattern, (unsigned char *)line,
 533                                  eol - line, 0, flags, p->pcre2_match_data,
 534                                  NULL);
 535
 536        if (ret < 0 && ret != PCRE2_ERROR_NOMATCH) {
 537                pcre2_get_error_message(ret, errbuf, sizeof(errbuf));
 538                die("%s failed with error code %d: %s",
 539                    (p->pcre2_jit_on ? "pcre2_jit_match" : "pcre2_match"), ret,
 540                    errbuf);
 541        }
 542        if (ret > 0) {
 543                ovector = pcre2_get_ovector_pointer(p->pcre2_match_data);
 544                ret = 0;
 545                match->rm_so = (int)ovector[0];
 546                match->rm_eo = (int)ovector[1];
 547        }
 548
 549        return ret;
 550}
 551
 552static void free_pcre2_pattern(struct grep_pat *p)
 553{
 554        pcre2_compile_context_free(p->pcre2_compile_context);
 555        pcre2_code_free(p->pcre2_pattern);
 556        pcre2_match_data_free(p->pcre2_match_data);
 557        pcre2_jit_stack_free(p->pcre2_jit_stack);
 558        pcre2_match_context_free(p->pcre2_match_context);
 559}
 560#else /* !USE_LIBPCRE2 */
 561static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
 562{
 563        /*
 564         * Unreachable until USE_LIBPCRE2 becomes synonymous with
 565         * USE_LIBPCRE. See the sibling comment in
 566         * grep_set_pattern_type_option().
 567         */
 568        die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 569}
 570
 571static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
 572                regmatch_t *match, int eflags)
 573{
 574        return 1;
 575}
 576
 577static void free_pcre2_pattern(struct grep_pat *p)
 578{
 579}
 580#endif /* !USE_LIBPCRE2 */
 581
 582static void compile_fixed_regexp(struct grep_pat *p, struct grep_opt *opt)
 583{
 584        struct strbuf sb = STRBUF_INIT;
 585        int err;
 586        int regflags = opt->regflags;
 587
 588        basic_regex_quote_buf(&sb, p->pattern);
 589        if (opt->ignore_case)
 590                regflags |= REG_ICASE;
 591        err = regcomp(&p->regexp, sb.buf, regflags);
 592        if (opt->debug)
 593                fprintf(stderr, "fixed %s\n", sb.buf);
 594        strbuf_release(&sb);
 595        if (err) {
 596                char errbuf[1024];
 597                regerror(err, &p->regexp, errbuf, sizeof(errbuf));
 598                regfree(&p->regexp);
 599                compile_regexp_failed(p, errbuf);
 600        }
 601}
 602
 603static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 604{
 605        int icase, ascii_only;
 606        int err;
 607
 608        p->word_regexp = opt->word_regexp;
 609        p->ignore_case = opt->ignore_case;
 610        icase          = opt->regflags & REG_ICASE || p->ignore_case;
 611        ascii_only     = !has_non_ascii(p->pattern);
 612
 613        /*
 614         * Even when -F (fixed) asks us to do a non-regexp search, we
 615         * may not be able to correctly case-fold when -i
 616         * (ignore-case) is asked (in which case, we'll synthesize a
 617         * regexp to match the pattern that matches regexp special
 618         * characters literally, while ignoring case differences).  On
 619         * the other hand, even without -F, if the pattern does not
 620         * have any regexp special characters and there is no need for
 621         * case-folding search, we can internally turn it into a
 622         * simple string match using kws.  p->fixed tells us if we
 623         * want to use kws.
 624         */
 625        if (opt->fixed ||
 626            has_null(p->pattern, p->patternlen) ||
 627            is_fixed(p->pattern, p->patternlen))
 628                p->fixed = !icase || ascii_only;
 629        else
 630                p->fixed = 0;
 631
 632        if (p->fixed) {
 633                p->kws = kwsalloc(icase ? tolower_trans_tbl : NULL);
 634                kwsincr(p->kws, p->pattern, p->patternlen);
 635                kwsprep(p->kws);
 636                return;
 637        } else if (opt->fixed) {
 638                /*
 639                 * We come here when the pattern has the non-ascii
 640                 * characters we cannot case-fold, and asked to
 641                 * ignore-case.
 642                 */
 643                compile_fixed_regexp(p, opt);
 644                return;
 645        }
 646
 647        if (opt->pcre2) {
 648                compile_pcre2_pattern(p, opt);
 649                return;
 650        }
 651
 652        if (opt->pcre1) {
 653                compile_pcre1_regexp(p, opt);
 654                return;
 655        }
 656
 657        err = regcomp(&p->regexp, p->pattern, opt->regflags);
 658        if (err) {
 659                char errbuf[1024];
 660                regerror(err, &p->regexp, errbuf, 1024);
 661                regfree(&p->regexp);
 662                compile_regexp_failed(p, errbuf);
 663        }
 664}
 665
 666static struct grep_expr *compile_pattern_or(struct grep_pat **);
 667static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 668{
 669        struct grep_pat *p;
 670        struct grep_expr *x;
 671
 672        p = *list;
 673        if (!p)
 674                return NULL;
 675        switch (p->token) {
 676        case GREP_PATTERN: /* atom */
 677        case GREP_PATTERN_HEAD:
 678        case GREP_PATTERN_BODY:
 679                x = xcalloc(1, sizeof (struct grep_expr));
 680                x->node = GREP_NODE_ATOM;
 681                x->u.atom = p;
 682                *list = p->next;
 683                return x;
 684        case GREP_OPEN_PAREN:
 685                *list = p->next;
 686                x = compile_pattern_or(list);
 687                if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 688                        die("unmatched parenthesis");
 689                *list = (*list)->next;
 690                return x;
 691        default:
 692                return NULL;
 693        }
 694}
 695
 696static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 697{
 698        struct grep_pat *p;
 699        struct grep_expr *x;
 700
 701        p = *list;
 702        if (!p)
 703                return NULL;
 704        switch (p->token) {
 705        case GREP_NOT:
 706                if (!p->next)
 707                        die("--not not followed by pattern expression");
 708                *list = p->next;
 709                x = xcalloc(1, sizeof (struct grep_expr));
 710                x->node = GREP_NODE_NOT;
 711                x->u.unary = compile_pattern_not(list);
 712                if (!x->u.unary)
 713                        die("--not followed by non pattern expression");
 714                return x;
 715        default:
 716                return compile_pattern_atom(list);
 717        }
 718}
 719
 720static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 721{
 722        struct grep_pat *p;
 723        struct grep_expr *x, *y, *z;
 724
 725        x = compile_pattern_not(list);
 726        p = *list;
 727        if (p && p->token == GREP_AND) {
 728                if (!p->next)
 729                        die("--and not followed by pattern expression");
 730                *list = p->next;
 731                y = compile_pattern_and(list);
 732                if (!y)
 733                        die("--and not followed by pattern expression");
 734                z = xcalloc(1, sizeof (struct grep_expr));
 735                z->node = GREP_NODE_AND;
 736                z->u.binary.left = x;
 737                z->u.binary.right = y;
 738                return z;
 739        }
 740        return x;
 741}
 742
 743static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 744{
 745        struct grep_pat *p;
 746        struct grep_expr *x, *y, *z;
 747
 748        x = compile_pattern_and(list);
 749        p = *list;
 750        if (x && p && p->token != GREP_CLOSE_PAREN) {
 751                y = compile_pattern_or(list);
 752                if (!y)
 753                        die("not a pattern expression %s", p->pattern);
 754                z = xcalloc(1, sizeof (struct grep_expr));
 755                z->node = GREP_NODE_OR;
 756                z->u.binary.left = x;
 757                z->u.binary.right = y;
 758                return z;
 759        }
 760        return x;
 761}
 762
 763static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 764{
 765        return compile_pattern_or(list);
 766}
 767
 768static void indent(int in)
 769{
 770        while (in-- > 0)
 771                fputc(' ', stderr);
 772}
 773
 774static void dump_grep_pat(struct grep_pat *p)
 775{
 776        switch (p->token) {
 777        case GREP_AND: fprintf(stderr, "*and*"); break;
 778        case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break;
 779        case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break;
 780        case GREP_NOT: fprintf(stderr, "*not*"); break;
 781        case GREP_OR: fprintf(stderr, "*or*"); break;
 782
 783        case GREP_PATTERN: fprintf(stderr, "pattern"); break;
 784        case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break;
 785        case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break;
 786        }
 787
 788        switch (p->token) {
 789        default: break;
 790        case GREP_PATTERN_HEAD:
 791                fprintf(stderr, "<head %d>", p->field); break;
 792        case GREP_PATTERN_BODY:
 793                fprintf(stderr, "<body>"); break;
 794        }
 795        switch (p->token) {
 796        default: break;
 797        case GREP_PATTERN_HEAD:
 798        case GREP_PATTERN_BODY:
 799        case GREP_PATTERN:
 800                fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern);
 801                break;
 802        }
 803        fputc('\n', stderr);
 804}
 805
 806static void dump_grep_expression_1(struct grep_expr *x, int in)
 807{
 808        indent(in);
 809        switch (x->node) {
 810        case GREP_NODE_TRUE:
 811                fprintf(stderr, "true\n");
 812                break;
 813        case GREP_NODE_ATOM:
 814                dump_grep_pat(x->u.atom);
 815                break;
 816        case GREP_NODE_NOT:
 817                fprintf(stderr, "(not\n");
 818                dump_grep_expression_1(x->u.unary, in+1);
 819                indent(in);
 820                fprintf(stderr, ")\n");
 821                break;
 822        case GREP_NODE_AND:
 823                fprintf(stderr, "(and\n");
 824                dump_grep_expression_1(x->u.binary.left, in+1);
 825                dump_grep_expression_1(x->u.binary.right, in+1);
 826                indent(in);
 827                fprintf(stderr, ")\n");
 828                break;
 829        case GREP_NODE_OR:
 830                fprintf(stderr, "(or\n");
 831                dump_grep_expression_1(x->u.binary.left, in+1);
 832                dump_grep_expression_1(x->u.binary.right, in+1);
 833                indent(in);
 834                fprintf(stderr, ")\n");
 835                break;
 836        }
 837}
 838
 839static void dump_grep_expression(struct grep_opt *opt)
 840{
 841        struct grep_expr *x = opt->pattern_expression;
 842
 843        if (opt->all_match)
 844                fprintf(stderr, "[all-match]\n");
 845        dump_grep_expression_1(x, 0);
 846        fflush(NULL);
 847}
 848
 849static struct grep_expr *grep_true_expr(void)
 850{
 851        struct grep_expr *z = xcalloc(1, sizeof(*z));
 852        z->node = GREP_NODE_TRUE;
 853        return z;
 854}
 855
 856static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
 857{
 858        struct grep_expr *z = xcalloc(1, sizeof(*z));
 859        z->node = GREP_NODE_OR;
 860        z->u.binary.left = left;
 861        z->u.binary.right = right;
 862        return z;
 863}
 864
 865static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 866{
 867        struct grep_pat *p;
 868        struct grep_expr *header_expr;
 869        struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
 870        enum grep_header_field fld;
 871
 872        if (!opt->header_list)
 873                return NULL;
 874
 875        for (p = opt->header_list; p; p = p->next) {
 876                if (p->token != GREP_PATTERN_HEAD)
 877                        die("BUG: a non-header pattern in grep header list.");
 878                if (p->field < GREP_HEADER_FIELD_MIN ||
 879                    GREP_HEADER_FIELD_MAX <= p->field)
 880                        die("BUG: unknown header field %d", p->field);
 881                compile_regexp(p, opt);
 882        }
 883
 884        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 885                header_group[fld] = NULL;
 886
 887        for (p = opt->header_list; p; p = p->next) {
 888                struct grep_expr *h;
 889                struct grep_pat *pp = p;
 890
 891                h = compile_pattern_atom(&pp);
 892                if (!h || pp != p->next)
 893                        die("BUG: malformed header expr");
 894                if (!header_group[p->field]) {
 895                        header_group[p->field] = h;
 896                        continue;
 897                }
 898                header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 899        }
 900
 901        header_expr = NULL;
 902
 903        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 904                if (!header_group[fld])
 905                        continue;
 906                if (!header_expr)
 907                        header_expr = grep_true_expr();
 908                header_expr = grep_or_expr(header_group[fld], header_expr);
 909        }
 910        return header_expr;
 911}
 912
 913static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 914{
 915        struct grep_expr *z = x;
 916
 917        while (x) {
 918                assert(x->node == GREP_NODE_OR);
 919                if (x->u.binary.right &&
 920                    x->u.binary.right->node == GREP_NODE_TRUE) {
 921                        x->u.binary.right = y;
 922                        break;
 923                }
 924                x = x->u.binary.right;
 925        }
 926        return z;
 927}
 928
 929static void compile_grep_patterns_real(struct grep_opt *opt)
 930{
 931        struct grep_pat *p;
 932        struct grep_expr *header_expr = prep_header_patterns(opt);
 933
 934        for (p = opt->pattern_list; p; p = p->next) {
 935                switch (p->token) {
 936                case GREP_PATTERN: /* atom */
 937                case GREP_PATTERN_HEAD:
 938                case GREP_PATTERN_BODY:
 939                        compile_regexp(p, opt);
 940                        break;
 941                default:
 942                        opt->extended = 1;
 943                        break;
 944                }
 945        }
 946
 947        if (opt->all_match || header_expr)
 948                opt->extended = 1;
 949        else if (!opt->extended && !opt->debug)
 950                return;
 951
 952        p = opt->pattern_list;
 953        if (p)
 954                opt->pattern_expression = compile_pattern_expr(&p);
 955        if (p)
 956                die("incomplete pattern expression: %s", p->pattern);
 957
 958        if (!header_expr)
 959                return;
 960
 961        if (!opt->pattern_expression)
 962                opt->pattern_expression = header_expr;
 963        else if (opt->all_match)
 964                opt->pattern_expression = grep_splice_or(header_expr,
 965                                                         opt->pattern_expression);
 966        else
 967                opt->pattern_expression = grep_or_expr(opt->pattern_expression,
 968                                                       header_expr);
 969        opt->all_match = 1;
 970}
 971
 972void compile_grep_patterns(struct grep_opt *opt)
 973{
 974        compile_grep_patterns_real(opt);
 975        if (opt->debug)
 976                dump_grep_expression(opt);
 977}
 978
 979static void free_pattern_expr(struct grep_expr *x)
 980{
 981        switch (x->node) {
 982        case GREP_NODE_TRUE:
 983        case GREP_NODE_ATOM:
 984                break;
 985        case GREP_NODE_NOT:
 986                free_pattern_expr(x->u.unary);
 987                break;
 988        case GREP_NODE_AND:
 989        case GREP_NODE_OR:
 990                free_pattern_expr(x->u.binary.left);
 991                free_pattern_expr(x->u.binary.right);
 992                break;
 993        }
 994        free(x);
 995}
 996
 997void free_grep_patterns(struct grep_opt *opt)
 998{
 999        struct grep_pat *p, *n;
1000
1001        for (p = opt->pattern_list; p; p = n) {
1002                n = p->next;
1003                switch (p->token) {
1004                case GREP_PATTERN: /* atom */
1005                case GREP_PATTERN_HEAD:
1006                case GREP_PATTERN_BODY:
1007                        if (p->kws)
1008                                kwsfree(p->kws);
1009                        else if (p->pcre1_regexp)
1010                                free_pcre1_regexp(p);
1011                        else if (p->pcre2_pattern)
1012                                free_pcre2_pattern(p);
1013                        else
1014                                regfree(&p->regexp);
1015                        free(p->pattern);
1016                        break;
1017                default:
1018                        break;
1019                }
1020                free(p);
1021        }
1022
1023        if (!opt->extended)
1024                return;
1025        free_pattern_expr(opt->pattern_expression);
1026}
1027
1028static char *end_of_line(char *cp, unsigned long *left)
1029{
1030        unsigned long l = *left;
1031        while (l && *cp != '\n') {
1032                l--;
1033                cp++;
1034        }
1035        *left = l;
1036        return cp;
1037}
1038
1039static int word_char(char ch)
1040{
1041        return isalnum(ch) || ch == '_';
1042}
1043
1044static void output_color(struct grep_opt *opt, const void *data, size_t size,
1045                         const char *color)
1046{
1047        if (want_color(opt->color) && color && color[0]) {
1048                opt->output(opt, color, strlen(color));
1049                opt->output(opt, data, size);
1050                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
1051        } else
1052                opt->output(opt, data, size);
1053}
1054
1055static void output_sep(struct grep_opt *opt, char sign)
1056{
1057        if (opt->null_following_name)
1058                opt->output(opt, "\0", 1);
1059        else
1060                output_color(opt, &sign, 1, opt->color_sep);
1061}
1062
1063static void show_name(struct grep_opt *opt, const char *name)
1064{
1065        output_color(opt, name, strlen(name), opt->color_filename);
1066        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
1067}
1068
1069static int fixmatch(struct grep_pat *p, char *line, char *eol,
1070                    regmatch_t *match)
1071{
1072        struct kwsmatch kwsm;
1073        size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
1074        if (offset == -1) {
1075                match->rm_so = match->rm_eo = -1;
1076                return REG_NOMATCH;
1077        } else {
1078                match->rm_so = offset;
1079                match->rm_eo = match->rm_so + kwsm.size[0];
1080                return 0;
1081        }
1082}
1083
1084static int patmatch(struct grep_pat *p, char *line, char *eol,
1085                    regmatch_t *match, int eflags)
1086{
1087        int hit;
1088
1089        if (p->fixed)
1090                hit = !fixmatch(p, line, eol, match);
1091        else if (p->pcre1_regexp)
1092                hit = !pcre1match(p, line, eol, match, eflags);
1093        else if (p->pcre2_pattern)
1094                hit = !pcre2match(p, line, eol, match, eflags);
1095        else
1096                hit = !regexec_buf(&p->regexp, line, eol - line, 1, match,
1097                                   eflags);
1098
1099        return hit;
1100}
1101
1102static int strip_timestamp(char *bol, char **eol_p)
1103{
1104        char *eol = *eol_p;
1105        int ch;
1106
1107        while (bol < --eol) {
1108                if (*eol != '>')
1109                        continue;
1110                *eol_p = ++eol;
1111                ch = *eol;
1112                *eol = '\0';
1113                return ch;
1114        }
1115        return 0;
1116}
1117
1118static struct {
1119        const char *field;
1120        size_t len;
1121} header_field[] = {
1122        { "author ", 7 },
1123        { "committer ", 10 },
1124        { "reflog ", 7 },
1125};
1126
1127static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
1128                             enum grep_context ctx,
1129                             regmatch_t *pmatch, int eflags)
1130{
1131        int hit = 0;
1132        int saved_ch = 0;
1133        const char *start = bol;
1134
1135        if ((p->token != GREP_PATTERN) &&
1136            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
1137                return 0;
1138
1139        if (p->token == GREP_PATTERN_HEAD) {
1140                const char *field;
1141                size_t len;
1142                assert(p->field < ARRAY_SIZE(header_field));
1143                field = header_field[p->field].field;
1144                len = header_field[p->field].len;
1145                if (strncmp(bol, field, len))
1146                        return 0;
1147                bol += len;
1148                switch (p->field) {
1149                case GREP_HEADER_AUTHOR:
1150                case GREP_HEADER_COMMITTER:
1151                        saved_ch = strip_timestamp(bol, &eol);
1152                        break;
1153                default:
1154                        break;
1155                }
1156        }
1157
1158 again:
1159        hit = patmatch(p, bol, eol, pmatch, eflags);
1160
1161        if (hit && p->word_regexp) {
1162                if ((pmatch[0].rm_so < 0) ||
1163                    (eol - bol) < pmatch[0].rm_so ||
1164                    (pmatch[0].rm_eo < 0) ||
1165                    (eol - bol) < pmatch[0].rm_eo)
1166                        die("regexp returned nonsense");
1167
1168                /* Match beginning must be either beginning of the
1169                 * line, or at word boundary (i.e. the last char must
1170                 * not be a word char).  Similarly, match end must be
1171                 * either end of the line, or at word boundary
1172                 * (i.e. the next char must not be a word char).
1173                 */
1174                if ( ((pmatch[0].rm_so == 0) ||
1175                      !word_char(bol[pmatch[0].rm_so-1])) &&
1176                     ((pmatch[0].rm_eo == (eol-bol)) ||
1177                      !word_char(bol[pmatch[0].rm_eo])) )
1178                        ;
1179                else
1180                        hit = 0;
1181
1182                /* Words consist of at least one character. */
1183                if (pmatch->rm_so == pmatch->rm_eo)
1184                        hit = 0;
1185
1186                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
1187                        /* There could be more than one match on the
1188                         * line, and the first match might not be
1189                         * strict word match.  But later ones could be!
1190                         * Forward to the next possible start, i.e. the
1191                         * next position following a non-word char.
1192                         */
1193                        bol = pmatch[0].rm_so + bol + 1;
1194                        while (word_char(bol[-1]) && bol < eol)
1195                                bol++;
1196                        eflags |= REG_NOTBOL;
1197                        if (bol < eol)
1198                                goto again;
1199                }
1200        }
1201        if (p->token == GREP_PATTERN_HEAD && saved_ch)
1202                *eol = saved_ch;
1203        if (hit) {
1204                pmatch[0].rm_so += bol - start;
1205                pmatch[0].rm_eo += bol - start;
1206        }
1207        return hit;
1208}
1209
1210static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
1211                           enum grep_context ctx, int collect_hits)
1212{
1213        int h = 0;
1214        regmatch_t match;
1215
1216        if (!x)
1217                die("Not a valid grep expression");
1218        switch (x->node) {
1219        case GREP_NODE_TRUE:
1220                h = 1;
1221                break;
1222        case GREP_NODE_ATOM:
1223                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
1224                break;
1225        case GREP_NODE_NOT:
1226                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
1227                break;
1228        case GREP_NODE_AND:
1229                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
1230                        return 0;
1231                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
1232                break;
1233        case GREP_NODE_OR:
1234                if (!collect_hits)
1235                        return (match_expr_eval(x->u.binary.left,
1236                                                bol, eol, ctx, 0) ||
1237                                match_expr_eval(x->u.binary.right,
1238                                                bol, eol, ctx, 0));
1239                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
1240                x->u.binary.left->hit |= h;
1241                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
1242                break;
1243        default:
1244                die("Unexpected node type (internal error) %d", x->node);
1245        }
1246        if (collect_hits)
1247                x->hit |= h;
1248        return h;
1249}
1250
1251static int match_expr(struct grep_opt *opt, char *bol, char *eol,
1252                      enum grep_context ctx, int collect_hits)
1253{
1254        struct grep_expr *x = opt->pattern_expression;
1255        return match_expr_eval(x, bol, eol, ctx, collect_hits);
1256}
1257
1258static int match_line(struct grep_opt *opt, char *bol, char *eol,
1259                      enum grep_context ctx, int collect_hits)
1260{
1261        struct grep_pat *p;
1262        regmatch_t match;
1263
1264        if (opt->extended)
1265                return match_expr(opt, bol, eol, ctx, collect_hits);
1266
1267        /* we do not call with collect_hits without being extended */
1268        for (p = opt->pattern_list; p; p = p->next) {
1269                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
1270                        return 1;
1271        }
1272        return 0;
1273}
1274
1275static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
1276                              enum grep_context ctx,
1277                              regmatch_t *pmatch, int eflags)
1278{
1279        regmatch_t match;
1280
1281        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
1282                return 0;
1283        if (match.rm_so < 0 || match.rm_eo < 0)
1284                return 0;
1285        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
1286                if (match.rm_so > pmatch->rm_so)
1287                        return 1;
1288                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
1289                        return 1;
1290        }
1291        pmatch->rm_so = match.rm_so;
1292        pmatch->rm_eo = match.rm_eo;
1293        return 1;
1294}
1295
1296static int next_match(struct grep_opt *opt, char *bol, char *eol,
1297                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
1298{
1299        struct grep_pat *p;
1300        int hit = 0;
1301
1302        pmatch->rm_so = pmatch->rm_eo = -1;
1303        if (bol < eol) {
1304                for (p = opt->pattern_list; p; p = p->next) {
1305                        switch (p->token) {
1306                        case GREP_PATTERN: /* atom */
1307                        case GREP_PATTERN_HEAD:
1308                        case GREP_PATTERN_BODY:
1309                                hit |= match_next_pattern(p, bol, eol, ctx,
1310                                                          pmatch, eflags);
1311                                break;
1312                        default:
1313                                break;
1314                        }
1315                }
1316        }
1317        return hit;
1318}
1319
1320static void show_line(struct grep_opt *opt, char *bol, char *eol,
1321                      const char *name, unsigned lno, char sign)
1322{
1323        int rest = eol - bol;
1324        const char *match_color, *line_color = NULL;
1325
1326        if (opt->file_break && opt->last_shown == 0) {
1327                if (opt->show_hunk_mark)
1328                        opt->output(opt, "\n", 1);
1329        } else if (opt->pre_context || opt->post_context || opt->funcbody) {
1330                if (opt->last_shown == 0) {
1331                        if (opt->show_hunk_mark) {
1332                                output_color(opt, "--", 2, opt->color_sep);
1333                                opt->output(opt, "\n", 1);
1334                        }
1335                } else if (lno > opt->last_shown + 1) {
1336                        output_color(opt, "--", 2, opt->color_sep);
1337                        opt->output(opt, "\n", 1);
1338                }
1339        }
1340        if (opt->heading && opt->last_shown == 0) {
1341                output_color(opt, name, strlen(name), opt->color_filename);
1342                opt->output(opt, "\n", 1);
1343        }
1344        opt->last_shown = lno;
1345
1346        if (!opt->heading && opt->pathname) {
1347                output_color(opt, name, strlen(name), opt->color_filename);
1348                output_sep(opt, sign);
1349        }
1350        if (opt->linenum) {
1351                char buf[32];
1352                xsnprintf(buf, sizeof(buf), "%d", lno);
1353                output_color(opt, buf, strlen(buf), opt->color_lineno);
1354                output_sep(opt, sign);
1355        }
1356        if (opt->color) {
1357                regmatch_t match;
1358                enum grep_context ctx = GREP_CONTEXT_BODY;
1359                int ch = *eol;
1360                int eflags = 0;
1361
1362                if (sign == ':')
1363                        match_color = opt->color_match_selected;
1364                else
1365                        match_color = opt->color_match_context;
1366                if (sign == ':')
1367                        line_color = opt->color_selected;
1368                else if (sign == '-')
1369                        line_color = opt->color_context;
1370                else if (sign == '=')
1371                        line_color = opt->color_function;
1372                *eol = '\0';
1373                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
1374                        if (match.rm_so == match.rm_eo)
1375                                break;
1376
1377                        output_color(opt, bol, match.rm_so, line_color);
1378                        output_color(opt, bol + match.rm_so,
1379                                     match.rm_eo - match.rm_so, match_color);
1380                        bol += match.rm_eo;
1381                        rest -= match.rm_eo;
1382                        eflags = REG_NOTBOL;
1383                }
1384                *eol = ch;
1385        }
1386        output_color(opt, bol, rest, line_color);
1387        opt->output(opt, "\n", 1);
1388}
1389
1390#ifndef NO_PTHREADS
1391int grep_use_locks;
1392
1393/*
1394 * This lock protects access to the gitattributes machinery, which is
1395 * not thread-safe.
1396 */
1397pthread_mutex_t grep_attr_mutex;
1398
1399static inline void grep_attr_lock(void)
1400{
1401        if (grep_use_locks)
1402                pthread_mutex_lock(&grep_attr_mutex);
1403}
1404
1405static inline void grep_attr_unlock(void)
1406{
1407        if (grep_use_locks)
1408                pthread_mutex_unlock(&grep_attr_mutex);
1409}
1410
1411/*
1412 * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
1413 */
1414pthread_mutex_t grep_read_mutex;
1415
1416#else
1417#define grep_attr_lock()
1418#define grep_attr_unlock()
1419#endif
1420
1421static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
1422{
1423        xdemitconf_t *xecfg = opt->priv;
1424        if (xecfg && !xecfg->find_func) {
1425                grep_source_load_driver(gs);
1426                if (gs->driver->funcname.pattern) {
1427                        const struct userdiff_funcname *pe = &gs->driver->funcname;
1428                        xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1429                } else {
1430                        xecfg = opt->priv = NULL;
1431                }
1432        }
1433
1434        if (xecfg) {
1435                char buf[1];
1436                return xecfg->find_func(bol, eol - bol, buf, 1,
1437                                        xecfg->find_func_priv) >= 0;
1438        }
1439
1440        if (bol == eol)
1441                return 0;
1442        if (isalpha(*bol) || *bol == '_' || *bol == '$')
1443                return 1;
1444        return 0;
1445}
1446
1447static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1448                               char *bol, unsigned lno)
1449{
1450        while (bol > gs->buf) {
1451                char *eol = --bol;
1452
1453                while (bol > gs->buf && bol[-1] != '\n')
1454                        bol--;
1455                lno--;
1456
1457                if (lno <= opt->last_shown)
1458                        break;
1459
1460                if (match_funcname(opt, gs, bol, eol)) {
1461                        show_line(opt, bol, eol, gs->name, lno, '=');
1462                        break;
1463                }
1464        }
1465}
1466
1467static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1468                             char *bol, char *end, unsigned lno)
1469{
1470        unsigned cur = lno, from = 1, funcname_lno = 0;
1471        int funcname_needed = !!opt->funcname;
1472
1473        if (opt->funcbody && !match_funcname(opt, gs, bol, end))
1474                funcname_needed = 2;
1475
1476        if (opt->pre_context < lno)
1477                from = lno - opt->pre_context;
1478        if (from <= opt->last_shown)
1479                from = opt->last_shown + 1;
1480
1481        /* Rewind. */
1482        while (bol > gs->buf &&
1483               cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) {
1484                char *eol = --bol;
1485
1486                while (bol > gs->buf && bol[-1] != '\n')
1487                        bol--;
1488                cur--;
1489                if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1490                        funcname_lno = cur;
1491                        funcname_needed = 0;
1492                }
1493        }
1494
1495        /* We need to look even further back to find a function signature. */
1496        if (opt->funcname && funcname_needed)
1497                show_funcname_line(opt, gs, bol, cur);
1498
1499        /* Back forward. */
1500        while (cur < lno) {
1501                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1502
1503                while (*eol != '\n')
1504                        eol++;
1505                show_line(opt, bol, eol, gs->name, cur, sign);
1506                bol = eol + 1;
1507                cur++;
1508        }
1509}
1510
1511static int should_lookahead(struct grep_opt *opt)
1512{
1513        struct grep_pat *p;
1514
1515        if (opt->extended)
1516                return 0; /* punt for too complex stuff */
1517        if (opt->invert)
1518                return 0;
1519        for (p = opt->pattern_list; p; p = p->next) {
1520                if (p->token != GREP_PATTERN)
1521                        return 0; /* punt for "header only" and stuff */
1522        }
1523        return 1;
1524}
1525
1526static int look_ahead(struct grep_opt *opt,
1527                      unsigned long *left_p,
1528                      unsigned *lno_p,
1529                      char **bol_p)
1530{
1531        unsigned lno = *lno_p;
1532        char *bol = *bol_p;
1533        struct grep_pat *p;
1534        char *sp, *last_bol;
1535        regoff_t earliest = -1;
1536
1537        for (p = opt->pattern_list; p; p = p->next) {
1538                int hit;
1539                regmatch_t m;
1540
1541                hit = patmatch(p, bol, bol + *left_p, &m, 0);
1542                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1543                        continue;
1544                if (earliest < 0 || m.rm_so < earliest)
1545                        earliest = m.rm_so;
1546        }
1547
1548        if (earliest < 0) {
1549                *bol_p = bol + *left_p;
1550                *left_p = 0;
1551                return 1;
1552        }
1553        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1554                ; /* find the beginning of the line */
1555        last_bol = sp;
1556
1557        for (sp = bol; sp < last_bol; sp++) {
1558                if (*sp == '\n')
1559                        lno++;
1560        }
1561        *left_p -= last_bol - bol;
1562        *bol_p = last_bol;
1563        *lno_p = lno;
1564        return 0;
1565}
1566
1567static int fill_textconv_grep(struct userdiff_driver *driver,
1568                              struct grep_source *gs)
1569{
1570        struct diff_filespec *df;
1571        char *buf;
1572        size_t size;
1573
1574        if (!driver || !driver->textconv)
1575                return grep_source_load(gs);
1576
1577        /*
1578         * The textconv interface is intimately tied to diff_filespecs, so we
1579         * have to pretend to be one. If we could unify the grep_source
1580         * and diff_filespec structs, this mess could just go away.
1581         */
1582        df = alloc_filespec(gs->path);
1583        switch (gs->type) {
1584        case GREP_SOURCE_OID:
1585                fill_filespec(df, gs->identifier, 1, 0100644);
1586                break;
1587        case GREP_SOURCE_FILE:
1588                fill_filespec(df, &null_oid, 0, 0100644);
1589                break;
1590        default:
1591                die("BUG: attempt to textconv something without a path?");
1592        }
1593
1594        /*
1595         * fill_textconv is not remotely thread-safe; it may load objects
1596         * behind the scenes, and it modifies the global diff tempfile
1597         * structure.
1598         */
1599        grep_read_lock();
1600        size = fill_textconv(driver, df, &buf);
1601        grep_read_unlock();
1602        free_filespec(df);
1603
1604        /*
1605         * The normal fill_textconv usage by the diff machinery would just keep
1606         * the textconv'd buf separate from the diff_filespec. But much of the
1607         * grep code passes around a grep_source and assumes that its "buf"
1608         * pointer is the beginning of the thing we are searching. So let's
1609         * install our textconv'd version into the grep_source, taking care not
1610         * to leak any existing buffer.
1611         */
1612        grep_source_clear_data(gs);
1613        gs->buf = buf;
1614        gs->size = size;
1615
1616        return 0;
1617}
1618
1619static int is_empty_line(const char *bol, const char *eol)
1620{
1621        while (bol < eol && isspace(*bol))
1622                bol++;
1623        return bol == eol;
1624}
1625
1626static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1627{
1628        char *bol;
1629        char *peek_bol = NULL;
1630        unsigned long left;
1631        unsigned lno = 1;
1632        unsigned last_hit = 0;
1633        int binary_match_only = 0;
1634        unsigned count = 0;
1635        int try_lookahead = 0;
1636        int show_function = 0;
1637        struct userdiff_driver *textconv = NULL;
1638        enum grep_context ctx = GREP_CONTEXT_HEAD;
1639        xdemitconf_t xecfg;
1640
1641        if (!opt->output)
1642                opt->output = std_output;
1643
1644        if (opt->pre_context || opt->post_context || opt->file_break ||
1645            opt->funcbody) {
1646                /* Show hunk marks, except for the first file. */
1647                if (opt->last_shown)
1648                        opt->show_hunk_mark = 1;
1649                /*
1650                 * If we're using threads then we can't easily identify
1651                 * the first file.  Always put hunk marks in that case
1652                 * and skip the very first one later in work_done().
1653                 */
1654                if (opt->output != std_output)
1655                        opt->show_hunk_mark = 1;
1656        }
1657        opt->last_shown = 0;
1658
1659        if (opt->allow_textconv) {
1660                grep_source_load_driver(gs);
1661                /*
1662                 * We might set up the shared textconv cache data here, which
1663                 * is not thread-safe.
1664                 */
1665                grep_attr_lock();
1666                textconv = userdiff_get_textconv(gs->driver);
1667                grep_attr_unlock();
1668        }
1669
1670        /*
1671         * We know the result of a textconv is text, so we only have to care
1672         * about binary handling if we are not using it.
1673         */
1674        if (!textconv) {
1675                switch (opt->binary) {
1676                case GREP_BINARY_DEFAULT:
1677                        if (grep_source_is_binary(gs))
1678                                binary_match_only = 1;
1679                        break;
1680                case GREP_BINARY_NOMATCH:
1681                        if (grep_source_is_binary(gs))
1682                                return 0; /* Assume unmatch */
1683                        break;
1684                case GREP_BINARY_TEXT:
1685                        break;
1686                default:
1687                        die("BUG: unknown binary handling mode");
1688                }
1689        }
1690
1691        memset(&xecfg, 0, sizeof(xecfg));
1692        opt->priv = &xecfg;
1693
1694        try_lookahead = should_lookahead(opt);
1695
1696        if (fill_textconv_grep(textconv, gs) < 0)
1697                return 0;
1698
1699        bol = gs->buf;
1700        left = gs->size;
1701        while (left) {
1702                char *eol, ch;
1703                int hit;
1704
1705                /*
1706                 * look_ahead() skips quickly to the line that possibly
1707                 * has the next hit; don't call it if we need to do
1708                 * something more than just skipping the current line
1709                 * in response to an unmatch for the current line.  E.g.
1710                 * inside a post-context window, we will show the current
1711                 * line as a context around the previous hit when it
1712                 * doesn't hit.
1713                 */
1714                if (try_lookahead
1715                    && !(last_hit
1716                         && (show_function ||
1717                             lno <= last_hit + opt->post_context))
1718                    && look_ahead(opt, &left, &lno, &bol))
1719                        break;
1720                eol = end_of_line(bol, &left);
1721                ch = *eol;
1722                *eol = 0;
1723
1724                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1725                        ctx = GREP_CONTEXT_BODY;
1726
1727                hit = match_line(opt, bol, eol, ctx, collect_hits);
1728                *eol = ch;
1729
1730                if (collect_hits)
1731                        goto next_line;
1732
1733                /* "grep -v -e foo -e bla" should list lines
1734                 * that do not have either, so inversion should
1735                 * be done outside.
1736                 */
1737                if (opt->invert)
1738                        hit = !hit;
1739                if (opt->unmatch_name_only) {
1740                        if (hit)
1741                                return 0;
1742                        goto next_line;
1743                }
1744                if (hit) {
1745                        count++;
1746                        if (opt->status_only)
1747                                return 1;
1748                        if (opt->name_only) {
1749                                show_name(opt, gs->name);
1750                                return 1;
1751                        }
1752                        if (opt->count)
1753                                goto next_line;
1754                        if (binary_match_only) {
1755                                opt->output(opt, "Binary file ", 12);
1756                                output_color(opt, gs->name, strlen(gs->name),
1757                                             opt->color_filename);
1758                                opt->output(opt, " matches\n", 9);
1759                                return 1;
1760                        }
1761                        /* Hit at this line.  If we haven't shown the
1762                         * pre-context lines, we would need to show them.
1763                         */
1764                        if (opt->pre_context || opt->funcbody)
1765                                show_pre_context(opt, gs, bol, eol, lno);
1766                        else if (opt->funcname)
1767                                show_funcname_line(opt, gs, bol, lno);
1768                        show_line(opt, bol, eol, gs->name, lno, ':');
1769                        last_hit = lno;
1770                        if (opt->funcbody)
1771                                show_function = 1;
1772                        goto next_line;
1773                }
1774                if (show_function && (!peek_bol || peek_bol < bol)) {
1775                        unsigned long peek_left = left;
1776                        char *peek_eol = eol;
1777
1778                        /*
1779                         * Trailing empty lines are not interesting.
1780                         * Peek past them to see if they belong to the
1781                         * body of the current function.
1782                         */
1783                        peek_bol = bol;
1784                        while (is_empty_line(peek_bol, peek_eol)) {
1785                                peek_bol = peek_eol + 1;
1786                                peek_eol = end_of_line(peek_bol, &peek_left);
1787                        }
1788
1789                        if (match_funcname(opt, gs, peek_bol, peek_eol))
1790                                show_function = 0;
1791                }
1792                if (show_function ||
1793                    (last_hit && lno <= last_hit + opt->post_context)) {
1794                        /* If the last hit is within the post context,
1795                         * we need to show this line.
1796                         */
1797                        show_line(opt, bol, eol, gs->name, lno, '-');
1798                }
1799
1800        next_line:
1801                bol = eol + 1;
1802                if (!left)
1803                        break;
1804                left--;
1805                lno++;
1806        }
1807
1808        if (collect_hits)
1809                return 0;
1810
1811        if (opt->status_only)
1812                return 0;
1813        if (opt->unmatch_name_only) {
1814                /* We did not see any hit, so we want to show this */
1815                show_name(opt, gs->name);
1816                return 1;
1817        }
1818
1819        xdiff_clear_find_func(&xecfg);
1820        opt->priv = NULL;
1821
1822        /* NEEDSWORK:
1823         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1824         * which feels mostly useless but sometimes useful.  Maybe
1825         * make it another option?  For now suppress them.
1826         */
1827        if (opt->count && count) {
1828                char buf[32];
1829                if (opt->pathname) {
1830                        output_color(opt, gs->name, strlen(gs->name),
1831                                     opt->color_filename);
1832                        output_sep(opt, ':');
1833                }
1834                xsnprintf(buf, sizeof(buf), "%u\n", count);
1835                opt->output(opt, buf, strlen(buf));
1836                return 1;
1837        }
1838        return !!last_hit;
1839}
1840
1841static void clr_hit_marker(struct grep_expr *x)
1842{
1843        /* All-hit markers are meaningful only at the very top level
1844         * OR node.
1845         */
1846        while (1) {
1847                x->hit = 0;
1848                if (x->node != GREP_NODE_OR)
1849                        return;
1850                x->u.binary.left->hit = 0;
1851                x = x->u.binary.right;
1852        }
1853}
1854
1855static int chk_hit_marker(struct grep_expr *x)
1856{
1857        /* Top level nodes have hit markers.  See if they all are hits */
1858        while (1) {
1859                if (x->node != GREP_NODE_OR)
1860                        return x->hit;
1861                if (!x->u.binary.left->hit)
1862                        return 0;
1863                x = x->u.binary.right;
1864        }
1865}
1866
1867int grep_source(struct grep_opt *opt, struct grep_source *gs)
1868{
1869        /*
1870         * we do not have to do the two-pass grep when we do not check
1871         * buffer-wide "all-match".
1872         */
1873        if (!opt->all_match)
1874                return grep_source_1(opt, gs, 0);
1875
1876        /* Otherwise the toplevel "or" terms hit a bit differently.
1877         * We first clear hit markers from them.
1878         */
1879        clr_hit_marker(opt->pattern_expression);
1880        grep_source_1(opt, gs, 1);
1881
1882        if (!chk_hit_marker(opt->pattern_expression))
1883                return 0;
1884
1885        return grep_source_1(opt, gs, 0);
1886}
1887
1888int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1889{
1890        struct grep_source gs;
1891        int r;
1892
1893        grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL, NULL);
1894        gs.buf = buf;
1895        gs.size = size;
1896
1897        r = grep_source(opt, &gs);
1898
1899        grep_source_clear(&gs);
1900        return r;
1901}
1902
1903void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1904                      const char *name, const char *path,
1905                      const void *identifier)
1906{
1907        gs->type = type;
1908        gs->name = xstrdup_or_null(name);
1909        gs->path = xstrdup_or_null(path);
1910        gs->buf = NULL;
1911        gs->size = 0;
1912        gs->driver = NULL;
1913
1914        switch (type) {
1915        case GREP_SOURCE_FILE:
1916                gs->identifier = xstrdup(identifier);
1917                break;
1918        case GREP_SOURCE_SUBMODULE:
1919                if (!identifier) {
1920                        gs->identifier = NULL;
1921                        break;
1922                }
1923                /*
1924                 * FALL THROUGH
1925                 * If the identifier is non-NULL (in the submodule case) it
1926                 * will be a SHA1 that needs to be copied.
1927                 */
1928        case GREP_SOURCE_OID:
1929                gs->identifier = oiddup(identifier);
1930                break;
1931        case GREP_SOURCE_BUF:
1932                gs->identifier = NULL;
1933                break;
1934        }
1935}
1936
1937void grep_source_clear(struct grep_source *gs)
1938{
1939        FREE_AND_NULL(gs->name);
1940        FREE_AND_NULL(gs->path);
1941        FREE_AND_NULL(gs->identifier);
1942        grep_source_clear_data(gs);
1943}
1944
1945void grep_source_clear_data(struct grep_source *gs)
1946{
1947        switch (gs->type) {
1948        case GREP_SOURCE_FILE:
1949        case GREP_SOURCE_OID:
1950        case GREP_SOURCE_SUBMODULE:
1951                FREE_AND_NULL(gs->buf);
1952                gs->size = 0;
1953                break;
1954        case GREP_SOURCE_BUF:
1955                /* leave user-provided buf intact */
1956                break;
1957        }
1958}
1959
1960static int grep_source_load_oid(struct grep_source *gs)
1961{
1962        enum object_type type;
1963
1964        grep_read_lock();
1965        gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
1966        grep_read_unlock();
1967
1968        if (!gs->buf)
1969                return error(_("'%s': unable to read %s"),
1970                             gs->name,
1971                             oid_to_hex(gs->identifier));
1972        return 0;
1973}
1974
1975static int grep_source_load_file(struct grep_source *gs)
1976{
1977        const char *filename = gs->identifier;
1978        struct stat st;
1979        char *data;
1980        size_t size;
1981        int i;
1982
1983        if (lstat(filename, &st) < 0) {
1984        err_ret:
1985                if (errno != ENOENT)
1986                        error_errno(_("failed to stat '%s'"), filename);
1987                return -1;
1988        }
1989        if (!S_ISREG(st.st_mode))
1990                return -1;
1991        size = xsize_t(st.st_size);
1992        i = open(filename, O_RDONLY);
1993        if (i < 0)
1994                goto err_ret;
1995        data = xmallocz(size);
1996        if (st.st_size != read_in_full(i, data, size)) {
1997                error_errno(_("'%s': short read"), filename);
1998                close(i);
1999                free(data);
2000                return -1;
2001        }
2002        close(i);
2003
2004        gs->buf = data;
2005        gs->size = size;
2006        return 0;
2007}
2008
2009static int grep_source_load(struct grep_source *gs)
2010{
2011        if (gs->buf)
2012                return 0;
2013
2014        switch (gs->type) {
2015        case GREP_SOURCE_FILE:
2016                return grep_source_load_file(gs);
2017        case GREP_SOURCE_OID:
2018                return grep_source_load_oid(gs);
2019        case GREP_SOURCE_BUF:
2020                return gs->buf ? 0 : -1;
2021        case GREP_SOURCE_SUBMODULE:
2022                break;
2023        }
2024        die("BUG: invalid grep_source type to load");
2025}
2026
2027void grep_source_load_driver(struct grep_source *gs)
2028{
2029        if (gs->driver)
2030                return;
2031
2032        grep_attr_lock();
2033        if (gs->path)
2034                gs->driver = userdiff_find_by_path(gs->path);
2035        if (!gs->driver)
2036                gs->driver = userdiff_find_by_name("default");
2037        grep_attr_unlock();
2038}
2039
2040static int grep_source_is_binary(struct grep_source *gs)
2041{
2042        grep_source_load_driver(gs);
2043        if (gs->driver->binary != -1)
2044                return gs->driver->binary;
2045
2046        if (!grep_source_load(gs))
2047                return buffer_is_binary(gs->buf, gs->size);
2048
2049        return 0;
2050}