diff options
Diffstat (limited to 'grep.c')
| -rw-r--r-- | grep.c | 1188 |
1 files changed, 1188 insertions, 0 deletions
diff --git a/grep.c b/grep.c new file mode 100644 index 0000000000..b29d09c7f6 --- /dev/null +++ b/grep.c @@ -0,0 +1,1188 @@ +#include "cache.h" +#include "grep.h" +#include "userdiff.h" +#include "xdiff-interface.h" + +void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field field, const char *pat) +{ + struct grep_pat *p = xcalloc(1, sizeof(*p)); + p->pattern = pat; + p->patternlen = strlen(pat); + p->origin = "header"; + p->no = 0; + p->token = GREP_PATTERN_HEAD; + p->field = field; + *opt->header_tail = p; + opt->header_tail = &p->next; + p->next = NULL; +} + +void append_grep_pattern(struct grep_opt *opt, const char *pat, + const char *origin, int no, enum grep_pat_token t) +{ + append_grep_pat(opt, pat, strlen(pat), origin, no, t); +} + +void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, + const char *origin, int no, enum grep_pat_token t) +{ + struct grep_pat *p = xcalloc(1, sizeof(*p)); + p->pattern = pat; + p->patternlen = patlen; + p->origin = origin; + p->no = no; + p->token = t; + *opt->pattern_tail = p; + opt->pattern_tail = &p->next; + p->next = NULL; +} + +struct grep_opt *grep_opt_dup(const struct grep_opt *opt) +{ + struct grep_pat *pat; + struct grep_opt *ret = xmalloc(sizeof(struct grep_opt)); + *ret = *opt; + + ret->pattern_list = NULL; + ret->pattern_tail = &ret->pattern_list; + + for(pat = opt->pattern_list; pat != NULL; pat = pat->next) + { + if(pat->token == GREP_PATTERN_HEAD) + append_header_grep_pattern(ret, pat->field, + pat->pattern); + else + append_grep_pat(ret, pat->pattern, pat->patternlen, + pat->origin, pat->no, pat->token); + } + + return ret; +} + +static NORETURN void compile_regexp_failed(const struct grep_pat *p, + const char *error) +{ + char where[1024]; + + if (p->no) + sprintf(where, "In '%s' at %d, ", p->origin, p->no); + else if (p->origin) + sprintf(where, "%s, ", p->origin); + else + where[0] = 0; + + die("%s'%s': %s", where, p->pattern, error); +} + +#ifdef USE_LIBPCRE +static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt) +{ + const char *error; + int erroffset; + int options = 0; + + if (opt->ignore_case) + options |= PCRE_CASELESS; + + p->pcre_regexp = pcre_compile(p->pattern, options, &error, &erroffset, + NULL); + if (!p->pcre_regexp) + compile_regexp_failed(p, error); + + p->pcre_extra_info = pcre_study(p->pcre_regexp, 0, &error); + if (!p->pcre_extra_info && error) + die("%s", error); +} + +static int pcrematch(struct grep_pat *p, const char *line, const char *eol, + regmatch_t *match, int eflags) +{ + int ovector[30], ret, flags = 0; + + if (eflags & REG_NOTBOL) + flags |= PCRE_NOTBOL; + + ret = pcre_exec(p->pcre_regexp, p->pcre_extra_info, line, eol - line, + 0, flags, ovector, ARRAY_SIZE(ovector)); + if (ret < 0 && ret != PCRE_ERROR_NOMATCH) + die("pcre_exec failed with error code %d", ret); + if (ret > 0) { + ret = 0; + match->rm_so = ovector[0]; + match->rm_eo = ovector[1]; + } + + return ret; +} + +static void free_pcre_regexp(struct grep_pat *p) +{ + pcre_free(p->pcre_regexp); + pcre_free(p->pcre_extra_info); +} +#else /* !USE_LIBPCRE */ +static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt) +{ + die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE"); +} + +static int pcrematch(struct grep_pat *p, const char *line, const char *eol, + regmatch_t *match, int eflags) +{ + return 1; +} + +static void free_pcre_regexp(struct grep_pat *p) +{ +} +#endif /* !USE_LIBPCRE */ + +static int is_fixed(const char *s, size_t len) +{ + size_t i; + + /* regcomp cannot accept patterns with NULs so we + * consider any pattern containing a NUL fixed. + */ + if (memchr(s, 0, len)) + return 1; + + for (i = 0; i < len; i++) { + if (is_regex_special(s[i])) + return 0; + } + + return 1; +} + +static void compile_regexp(struct grep_pat *p, struct grep_opt *opt) +{ + int err; + + p->word_regexp = opt->word_regexp; + p->ignore_case = opt->ignore_case; + + if (opt->fixed || is_fixed(p->pattern, p->patternlen)) + p->fixed = 1; + else + p->fixed = 0; + + if (p->fixed) { + if (opt->regflags & REG_ICASE || p->ignore_case) { + static char trans[256]; + int i; + for (i = 0; i < 256; i++) + trans[i] = tolower(i); + p->kws = kwsalloc(trans); + } else { + p->kws = kwsalloc(NULL); + } + kwsincr(p->kws, p->pattern, p->patternlen); + kwsprep(p->kws); + return; + } + + if (opt->pcre) { + compile_pcre_regexp(p, opt); + return; + } + + err = regcomp(&p->regexp, p->pattern, opt->regflags); + if (err) { + char errbuf[1024]; + regerror(err, &p->regexp, errbuf, 1024); + regfree(&p->regexp); + compile_regexp_failed(p, errbuf); + } +} + +static struct grep_expr *compile_pattern_or(struct grep_pat **); +static struct grep_expr *compile_pattern_atom(struct grep_pat **list) +{ + struct grep_pat *p; + struct grep_expr *x; + + p = *list; + if (!p) + return NULL; + switch (p->token) { + case GREP_PATTERN: /* atom */ + case GREP_PATTERN_HEAD: + case GREP_PATTERN_BODY: + x = xcalloc(1, sizeof (struct grep_expr)); + x->node = GREP_NODE_ATOM; + x->u.atom = p; + *list = p->next; + return x; + case GREP_OPEN_PAREN: + *list = p->next; + x = compile_pattern_or(list); + if (!*list || (*list)->token != GREP_CLOSE_PAREN) + die("unmatched parenthesis"); + *list = (*list)->next; + return x; + default: + return NULL; + } +} + +static struct grep_expr *compile_pattern_not(struct grep_pat **list) +{ + struct grep_pat *p; + struct grep_expr *x; + + p = *list; + if (!p) + return NULL; + switch (p->token) { + case GREP_NOT: + if (!p->next) + die("--not not followed by pattern expression"); + *list = p->next; + x = xcalloc(1, sizeof (struct grep_expr)); + x->node = GREP_NODE_NOT; + x->u.unary = compile_pattern_not(list); + if (!x->u.unary) + die("--not followed by non pattern expression"); + return x; + default: + return compile_pattern_atom(list); + } +} + +static struct grep_expr *compile_pattern_and(struct grep_pat **list) +{ + struct grep_pat *p; + struct grep_expr *x, *y, *z; + + x = compile_pattern_not(list); + p = *list; + if (p && p->token == GREP_AND) { + if (!p->next) + die("--and not followed by pattern expression"); + *list = p->next; + y = compile_pattern_and(list); + if (!y) + die("--and not followed by pattern expression"); + z = xcalloc(1, sizeof (struct grep_expr)); + z->node = GREP_NODE_AND; + z->u.binary.left = x; + z->u.binary.right = y; + return z; + } + return x; +} + +static struct grep_expr *compile_pattern_or(struct grep_pat **list) +{ + struct grep_pat *p; + struct grep_expr *x, *y, *z; + + x = compile_pattern_and(list); + p = *list; + if (x && p && p->token != GREP_CLOSE_PAREN) { + y = compile_pattern_or(list); + if (!y) + die("not a pattern expression %s", p->pattern); + z = xcalloc(1, sizeof (struct grep_expr)); + z->node = GREP_NODE_OR; + z->u.binary.left = x; + z->u.binary.right = y; + return z; + } + return x; +} + +static struct grep_expr *compile_pattern_expr(struct grep_pat **list) +{ + return compile_pattern_or(list); +} + +static struct grep_expr *grep_true_expr(void) +{ + struct grep_expr *z = xcalloc(1, sizeof(*z)); + z->node = GREP_NODE_TRUE; + return z; +} + +static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right) +{ + struct grep_expr *z = xcalloc(1, sizeof(*z)); + z->node = GREP_NODE_OR; + z->u.binary.left = left; + z->u.binary.right = right; + return z; +} + +static struct grep_expr *prep_header_patterns(struct grep_opt *opt) +{ + struct grep_pat *p; + struct grep_expr *header_expr; + struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]); + enum grep_header_field fld; + + if (!opt->header_list) + return NULL; + p = opt->header_list; + for (p = opt->header_list; p; p = p->next) { + if (p->token != GREP_PATTERN_HEAD) + die("bug: a non-header pattern in grep header list."); + if (p->field < 0 || GREP_HEADER_FIELD_MAX <= p->field) + die("bug: unknown header field %d", p->field); + compile_regexp(p, opt); + } + + for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) + header_group[fld] = NULL; + + for (p = opt->header_list; p; p = p->next) { + struct grep_expr *h; + struct grep_pat *pp = p; + + h = compile_pattern_atom(&pp); + if (!h || pp != p->next) + die("bug: malformed header expr"); + if (!header_group[p->field]) { + header_group[p->field] = h; + continue; + } + header_group[p->field] = grep_or_expr(h, header_group[p->field]); + } + + header_expr = NULL; + + for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) { + if (!header_group[fld]) + continue; + if (!header_expr) + header_expr = grep_true_expr(); + header_expr = grep_or_expr(header_group[fld], header_expr); + } + return header_expr; +} + +void compile_grep_patterns(struct grep_opt *opt) +{ + struct grep_pat *p; + struct grep_expr *header_expr = prep_header_patterns(opt); + + for (p = opt->pattern_list; p; p = p->next) { + switch (p->token) { + case GREP_PATTERN: /* atom */ + case GREP_PATTERN_HEAD: + case GREP_PATTERN_BODY: + compile_regexp(p, opt); + break; + default: + opt->extended = 1; + break; + } + } + + if (opt->all_match || header_expr) + opt->extended = 1; + else if (!opt->extended) + return; + + p = opt->pattern_list; + if (p) + opt->pattern_expression = compile_pattern_expr(&p); + if (p) + die("incomplete pattern expression: %s", p->pattern); + + if (!header_expr) + return; + + if (!opt->pattern_expression) + opt->pattern_expression = header_expr; + else + opt->pattern_expression = grep_or_expr(opt->pattern_expression, + header_expr); + opt->all_match = 1; +} + +static void free_pattern_expr(struct grep_expr *x) +{ + switch (x->node) { + case GREP_NODE_TRUE: + case GREP_NODE_ATOM: + break; + case GREP_NODE_NOT: + free_pattern_expr(x->u.unary); + break; + case GREP_NODE_AND: + case GREP_NODE_OR: + free_pattern_expr(x->u.binary.left); + free_pattern_expr(x->u.binary.right); + break; + } + free(x); +} + +void free_grep_patterns(struct grep_opt *opt) +{ + struct grep_pat *p, *n; + + for (p = opt->pattern_list; p; p = n) { + n = p->next; + switch (p->token) { + case GREP_PATTERN: /* atom */ + case GREP_PATTERN_HEAD: + case GREP_PATTERN_BODY: + if (p->kws) + kwsfree(p->kws); + else if (p->pcre_regexp) + free_pcre_regexp(p); + else + regfree(&p->regexp); + break; + default: + break; + } + free(p); + } + + if (!opt->extended) + return; + free_pattern_expr(opt->pattern_expression); +} + +static char *end_of_line(char *cp, unsigned long *left) +{ + unsigned long l = *left; + while (l && *cp != '\n') { + l--; + cp++; + } + *left = l; + return cp; +} + +static int word_char(char ch) +{ + return isalnum(ch) || ch == '_'; +} + +static void output_color(struct grep_opt *opt, const void *data, size_t size, + const char *color) +{ + if (want_color(opt->color) && color && color[0]) { + opt->output(opt, color, strlen(color)); + opt->output(opt, data, size); + opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET)); + } else + opt->output(opt, data, size); +} + +static void output_sep(struct grep_opt *opt, char sign) +{ + if (opt->null_following_name) + opt->output(opt, "\0", 1); + else + output_color(opt, &sign, 1, opt->color_sep); +} + +static void show_name(struct grep_opt *opt, const char *name) +{ + output_color(opt, name, strlen(name), opt->color_filename); + opt->output(opt, opt->null_following_name ? "\0" : "\n", 1); +} + +static int fixmatch(struct grep_pat *p, char *line, char *eol, + regmatch_t *match) +{ + struct kwsmatch kwsm; + size_t offset = kwsexec(p->kws, line, eol - line, &kwsm); + if (offset == -1) { + match->rm_so = match->rm_eo = -1; + return REG_NOMATCH; + } else { + match->rm_so = offset; + match->rm_eo = match->rm_so + kwsm.size[0]; + return 0; + } +} + +static int regmatch(const regex_t *preg, char *line, char *eol, + regmatch_t *match, int eflags) +{ +#ifdef REG_STARTEND + match->rm_so = 0; + match->rm_eo = eol - line; + eflags |= REG_STARTEND; +#endif + return regexec(preg, line, 1, match, eflags); +} + +static int patmatch(struct grep_pat *p, char *line, char *eol, + regmatch_t *match, int eflags) +{ + int hit; + + if (p->fixed) + hit = !fixmatch(p, line, eol, match); + else if (p->pcre_regexp) + hit = !pcrematch(p, line, eol, match, eflags); + else + hit = !regmatch(&p->regexp, line, eol, match, eflags); + + return hit; +} + +static int strip_timestamp(char *bol, char **eol_p) +{ + char *eol = *eol_p; + int ch; + + while (bol < --eol) { + if (*eol != '>') + continue; + *eol_p = ++eol; + ch = *eol; + *eol = '\0'; + return ch; + } + return 0; +} + +static struct { + const char *field; + size_t len; +} header_field[] = { + { "author ", 7 }, + { "committer ", 10 }, +}; + +static int match_one_pattern(struct grep_pat *p, char *bol, char *eol, + enum grep_context ctx, + regmatch_t *pmatch, int eflags) +{ + int hit = 0; + int saved_ch = 0; + const char *start = bol; + + if ((p->token != GREP_PATTERN) && + ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD))) + return 0; + + if (p->token == GREP_PATTERN_HEAD) { + const char *field; + size_t len; + assert(p->field < ARRAY_SIZE(header_field)); + field = header_field[p->field].field; + len = header_field[p->field].len; + if (strncmp(bol, field, len)) + return 0; + bol += len; + saved_ch = strip_timestamp(bol, &eol); + } + + again: + hit = patmatch(p, bol, eol, pmatch, eflags); + + if (hit && p->word_regexp) { + if ((pmatch[0].rm_so < 0) || + (eol - bol) < pmatch[0].rm_so || + (pmatch[0].rm_eo < 0) || + (eol - bol) < pmatch[0].rm_eo) + die("regexp returned nonsense"); + + /* Match beginning must be either beginning of the + * line, or at word boundary (i.e. the last char must + * not be a word char). Similarly, match end must be + * either end of the line, or at word boundary + * (i.e. the next char must not be a word char). + */ + if ( ((pmatch[0].rm_so == 0) || + !word_char(bol[pmatch[0].rm_so-1])) && + ((pmatch[0].rm_eo == (eol-bol)) || + !word_char(bol[pmatch[0].rm_eo])) ) + ; + else + hit = 0; + + /* Words consist of at least one character. */ + if (pmatch->rm_so == pmatch->rm_eo) + hit = 0; + + if (!hit && pmatch[0].rm_so + bol + 1 < eol) { + /* There could be more than one match on the + * line, and the first match might not be + * strict word match. But later ones could be! + * Forward to the next possible start, i.e. the + * next position following a non-word char. + */ + bol = pmatch[0].rm_so + bol + 1; + while (word_char(bol[-1]) && bol < eol) + bol++; + eflags |= REG_NOTBOL; + if (bol < eol) + goto again; + } + } + if (p->token == GREP_PATTERN_HEAD && saved_ch) + *eol = saved_ch; + if (hit) { + pmatch[0].rm_so += bol - start; + pmatch[0].rm_eo += bol - start; + } + return hit; +} + +static int match_expr_eval(struct grep_expr *x, char *bol, char *eol, + enum grep_context ctx, int collect_hits) +{ + int h = 0; + regmatch_t match; + + if (!x) + die("Not a valid grep expression"); + switch (x->node) { + case GREP_NODE_TRUE: + h = 1; + break; + case GREP_NODE_ATOM: + h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0); + break; + case GREP_NODE_NOT: + h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0); + break; + case GREP_NODE_AND: + if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0)) + return 0; + h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0); + break; + case GREP_NODE_OR: + if (!collect_hits) + return (match_expr_eval(x->u.binary.left, + bol, eol, ctx, 0) || + match_expr_eval(x->u.binary.right, + bol, eol, ctx, 0)); + h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0); + x->u.binary.left->hit |= h; + h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1); + break; + default: + die("Unexpected node type (internal error) %d", x->node); + } + if (collect_hits) + x->hit |= h; + return h; +} + +static int match_expr(struct grep_opt *opt, char *bol, char *eol, + enum grep_context ctx, int collect_hits) +{ + struct grep_expr *x = opt->pattern_expression; + return match_expr_eval(x, bol, eol, ctx, collect_hits); +} + +static int match_line(struct grep_opt *opt, char *bol, char *eol, + enum grep_context ctx, int collect_hits) +{ + struct grep_pat *p; + regmatch_t match; + + if (opt->extended) + return match_expr(opt, bol, eol, ctx, collect_hits); + + /* we do not call with collect_hits without being extended */ + for (p = opt->pattern_list; p; p = p->next) { + if (match_one_pattern(p, bol, eol, ctx, &match, 0)) + return 1; + } + return 0; +} + +static int match_next_pattern(struct grep_pat *p, char *bol, char *eol, + enum grep_context ctx, + regmatch_t *pmatch, int eflags) +{ + regmatch_t match; + + if (!match_one_pattern(p, bol, eol, ctx, &match, eflags)) + return 0; + if (match.rm_so < 0 || match.rm_eo < 0) + return 0; + if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) { + if (match.rm_so > pmatch->rm_so) + return 1; + if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo) + return 1; + } + pmatch->rm_so = match.rm_so; + pmatch->rm_eo = match.rm_eo; + return 1; +} + +static int next_match(struct grep_opt *opt, char *bol, char *eol, + enum grep_context ctx, regmatch_t *pmatch, int eflags) +{ + struct grep_pat *p; + int hit = 0; + + pmatch->rm_so = pmatch->rm_eo = -1; + if (bol < eol) { + for (p = opt->pattern_list; p; p = p->next) { + switch (p->token) { + case GREP_PATTERN: /* atom */ + case GREP_PATTERN_HEAD: + case GREP_PATTERN_BODY: + hit |= match_next_pattern(p, bol, eol, ctx, + pmatch, eflags); + break; + default: + break; + } + } + } + return hit; +} + +static void show_line(struct grep_opt *opt, char *bol, char *eol, + const char *name, unsigned lno, char sign) +{ + int rest = eol - bol; + char *line_color = NULL; + + if (opt->file_break && opt->last_shown == 0) { + if (opt->show_hunk_mark) + opt->output(opt, "\n", 1); + } else if (opt->pre_context || opt->post_context || opt->funcbody) { + if (opt->last_shown == 0) { + if (opt->show_hunk_mark) { + output_color(opt, "--", 2, opt->color_sep); + opt->output(opt, "\n", 1); + } + } else if (lno > opt->last_shown + 1) { + output_color(opt, "--", 2, opt->color_sep); + opt->output(opt, "\n", 1); + } + } + if (opt->heading && opt->last_shown == 0) { + output_color(opt, name, strlen(name), opt->color_filename); + opt->output(opt, "\n", 1); + } + opt->last_shown = lno; + + if (!opt->heading && opt->pathname) { + output_color(opt, name, strlen(name), opt->color_filename); + output_sep(opt, sign); + } + if (opt->linenum) { + char buf[32]; + snprintf(buf, sizeof(buf), "%d", lno); + output_color(opt, buf, strlen(buf), opt->color_lineno); + output_sep(opt, sign); + } + if (opt->color) { + regmatch_t match; + enum grep_context ctx = GREP_CONTEXT_BODY; + int ch = *eol; + int eflags = 0; + + if (sign == ':') + line_color = opt->color_selected; + else if (sign == '-') + line_color = opt->color_context; + else if (sign == '=') + line_color = opt->color_function; + *eol = '\0'; + while (next_match(opt, bol, eol, ctx, &match, eflags)) { + if (match.rm_so == match.rm_eo) + break; + + output_color(opt, bol, match.rm_so, line_color); + output_color(opt, bol + match.rm_so, + match.rm_eo - match.rm_so, + opt->color_match); + bol += match.rm_eo; + rest -= match.rm_eo; + eflags = REG_NOTBOL; + } + *eol = ch; + } + output_color(opt, bol, rest, line_color); + opt->output(opt, "\n", 1); +} + +static int match_funcname(struct grep_opt *opt, char *bol, char *eol) +{ + xdemitconf_t *xecfg = opt->priv; + if (xecfg && xecfg->find_func) { + char buf[1]; + return xecfg->find_func(bol, eol - bol, buf, 1, + xecfg->find_func_priv) >= 0; + } + + if (bol == eol) + return 0; + if (isalpha(*bol) || *bol == '_' || *bol == '$') + return 1; + return 0; +} + +static void show_funcname_line(struct grep_opt *opt, const char *name, + char *buf, char *bol, unsigned lno) +{ + while (bol > buf) { + char *eol = --bol; + + while (bol > buf && bol[-1] != '\n') + bol--; + lno--; + + if (lno <= opt->last_shown) + break; + + if (match_funcname(opt, bol, eol)) { + show_line(opt, bol, eol, name, lno, '='); + break; + } + } +} + +static void show_pre_context(struct grep_opt *opt, const char *name, char *buf, + char *bol, char *end, unsigned lno) +{ + unsigned cur = lno, from = 1, funcname_lno = 0; + int funcname_needed = !!opt->funcname; + + if (opt->funcbody && !match_funcname(opt, bol, end)) + funcname_needed = 2; + + if (opt->pre_context < lno) + from = lno - opt->pre_context; + if (from <= opt->last_shown) + from = opt->last_shown + 1; + + /* Rewind. */ + while (bol > buf && + cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) { + char *eol = --bol; + + while (bol > buf && bol[-1] != '\n') + bol--; + cur--; + if (funcname_needed && match_funcname(opt, bol, eol)) { + funcname_lno = cur; + funcname_needed = 0; + } + } + + /* We need to look even further back to find a function signature. */ + if (opt->funcname && funcname_needed) + show_funcname_line(opt, name, buf, bol, cur); + + /* Back forward. */ + while (cur < lno) { + char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-'; + + while (*eol != '\n') + eol++; + show_line(opt, bol, eol, name, cur, sign); + bol = eol + 1; + cur++; + } +} + +static int should_lookahead(struct grep_opt *opt) +{ + struct grep_pat *p; + + if (opt->extended) + return 0; /* punt for too complex stuff */ + if (opt->invert) + return 0; + for (p = opt->pattern_list; p; p = p->next) { + if (p->token != GREP_PATTERN) + return 0; /* punt for "header only" and stuff */ + } + return 1; +} + +static int look_ahead(struct grep_opt *opt, + unsigned long *left_p, + unsigned *lno_p, + char **bol_p) +{ + unsigned lno = *lno_p; + char *bol = *bol_p; + struct grep_pat *p; + char *sp, *last_bol; + regoff_t earliest = -1; + + for (p = opt->pattern_list; p; p = p->next) { + int hit; + regmatch_t m; + + hit = patmatch(p, bol, bol + *left_p, &m, 0); + if (!hit || m.rm_so < 0 || m.rm_eo < 0) + continue; + if (earliest < 0 || m.rm_so < earliest) + earliest = m.rm_so; + } + + if (earliest < 0) { + *bol_p = bol + *left_p; + *left_p = 0; + return 1; + } + for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--) + ; /* find the beginning of the line */ + last_bol = sp; + + for (sp = bol; sp < last_bol; sp++) { + if (*sp == '\n') + lno++; + } + *left_p -= last_bol - bol; + *bol_p = last_bol; + *lno_p = lno; + return 0; +} + +int grep_threads_ok(const struct grep_opt *opt) +{ + /* If this condition is true, then we may use the attribute + * machinery in grep_buffer_1. The attribute code is not + * thread safe, so we disable the use of threads. + */ + if (opt->funcname && !opt->unmatch_name_only && !opt->status_only && + !opt->name_only) + return 0; + + return 1; +} + +static void std_output(struct grep_opt *opt, const void *buf, size_t size) +{ + fwrite(buf, size, 1, stdout); +} + +static int grep_buffer_1(struct grep_opt *opt, const char *name, + char *buf, unsigned long size, int collect_hits) +{ + char *bol = buf; + unsigned long left = size; + unsigned lno = 1; + unsigned last_hit = 0; + int binary_match_only = 0; + unsigned count = 0; + int try_lookahead = 0; + int show_function = 0; + enum grep_context ctx = GREP_CONTEXT_HEAD; + xdemitconf_t xecfg; + + if (!opt->output) + opt->output = std_output; + + if (opt->pre_context || opt->post_context || opt->file_break || + opt->funcbody) { + /* Show hunk marks, except for the first file. */ + if (opt->last_shown) + opt->show_hunk_mark = 1; + /* + * If we're using threads then we can't easily identify + * the first file. Always put hunk marks in that case + * and skip the very first one later in work_done(). + */ + if (opt->output != std_output) + opt->show_hunk_mark = 1; + } + opt->last_shown = 0; + + switch (opt->binary) { + case GREP_BINARY_DEFAULT: + if (buffer_is_binary(buf, size)) + binary_match_only = 1; + break; + case GREP_BINARY_NOMATCH: + if (buffer_is_binary(buf, size)) + return 0; /* Assume unmatch */ + break; + case GREP_BINARY_TEXT: + break; + default: + die("bug: unknown binary handling mode"); + } + + memset(&xecfg, 0, sizeof(xecfg)); + if (opt->funcname && !opt->unmatch_name_only && !opt->status_only && + !opt->name_only && !binary_match_only && !collect_hits) { + struct userdiff_driver *drv = userdiff_find_by_path(name); + if (drv && drv->funcname.pattern) { + const struct userdiff_funcname *pe = &drv->funcname; + xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags); + opt->priv = &xecfg; + } + } + try_lookahead = should_lookahead(opt); + + while (left) { + char *eol, ch; + int hit; + + /* + * look_ahead() skips quickly to the line that possibly + * has the next hit; don't call it if we need to do + * something more than just skipping the current line + * in response to an unmatch for the current line. E.g. + * inside a post-context window, we will show the current + * line as a context around the previous hit when it + * doesn't hit. + */ + if (try_lookahead + && !(last_hit + && (show_function || + lno <= last_hit + opt->post_context)) + && look_ahead(opt, &left, &lno, &bol)) + break; + eol = end_of_line(bol, &left); + ch = *eol; + *eol = 0; + + if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol)) + ctx = GREP_CONTEXT_BODY; + + hit = match_line(opt, bol, eol, ctx, collect_hits); + *eol = ch; + + if (collect_hits) + goto next_line; + + /* "grep -v -e foo -e bla" should list lines + * that do not have either, so inversion should + * be done outside. + */ + if (opt->invert) + hit = !hit; + if (opt->unmatch_name_only) { + if (hit) + return 0; + goto next_line; + } + if (hit) { + count++; + if (opt->status_only) + return 1; + if (opt->name_only) { + show_name(opt, name); + return 1; + } + if (opt->count) + goto next_line; + if (binary_match_only) { + opt->output(opt, "Binary file ", 12); + output_color(opt, name, strlen(name), + opt->color_filename); + opt->output(opt, " matches\n", 9); + return 1; + } + /* Hit at this line. If we haven't shown the + * pre-context lines, we would need to show them. + */ + if (opt->pre_context || opt->funcbody) + show_pre_context(opt, name, buf, bol, eol, lno); + else if (opt->funcname) + show_funcname_line(opt, name, buf, bol, lno); + show_line(opt, bol, eol, name, lno, ':'); + last_hit = lno; + if (opt->funcbody) + show_function = 1; + goto next_line; + } + if (show_function && match_funcname(opt, bol, eol)) + show_function = 0; + if (show_function || + (last_hit && lno <= last_hit + opt->post_context)) { + /* If the last hit is within the post context, + * we need to show this line. + */ + show_line(opt, bol, eol, name, lno, '-'); + } + + next_line: + bol = eol + 1; + if (!left) + break; + left--; + lno++; + } + + if (collect_hits) + return 0; + + if (opt->status_only) + return 0; + if (opt->unmatch_name_only) { + /* We did not see any hit, so we want to show this */ + show_name(opt, name); + return 1; + } + + xdiff_clear_find_func(&xecfg); + opt->priv = NULL; + + /* NEEDSWORK: + * The real "grep -c foo *.c" gives many "bar.c:0" lines, + * which feels mostly useless but sometimes useful. Maybe + * make it another option? For now suppress them. + */ + if (opt->count && count) { + char buf[32]; + output_color(opt, name, strlen(name), opt->color_filename); + output_sep(opt, ':'); + snprintf(buf, sizeof(buf), "%u\n", count); + opt->output(opt, buf, strlen(buf)); + return 1; + } + return !!last_hit; +} + +static void clr_hit_marker(struct grep_expr *x) +{ + /* All-hit markers are meaningful only at the very top level + * OR node. + */ + while (1) { + x->hit = 0; + if (x->node != GREP_NODE_OR) + return; + x->u.binary.left->hit = 0; + x = x->u.binary.right; + } +} + +static int chk_hit_marker(struct grep_expr *x) +{ + /* Top level nodes have hit markers. See if they all are hits */ + while (1) { + if (x->node != GREP_NODE_OR) + return x->hit; + if (!x->u.binary.left->hit) + return 0; + x = x->u.binary.right; + } +} + +int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size) +{ + /* + * we do not have to do the two-pass grep when we do not check + * buffer-wide "all-match". + */ + if (!opt->all_match) + return grep_buffer_1(opt, name, buf, size, 0); + + /* Otherwise the toplevel "or" terms hit a bit differently. + * We first clear hit markers from them. + */ + clr_hit_marker(opt->pattern_expression); + grep_buffer_1(opt, name, buf, size, 1); + + if (!chk_hit_marker(opt->pattern_expression)) + return 0; + + return grep_buffer_1(opt, name, buf, size, 0); +} |