Function compile_grep_patterns

grep.c:770–815

}

void compile_grep_patterns(struct grep_opt *opt)
{
	struct grep_pat *p;
	struct grep_expr *header_expr = prep_header_patterns(opt);
	int extended = 0;

	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:
			extended = 1;
			break;
		}
	}

	if (opt->all_match || opt->no_body_match || header_expr)
		extended = 1;
	else if (!extended)
		return;

	p = opt->pattern_list;
	if (p)
		opt->pattern_expression = compile_pattern_expr(&p);
	if (p)
		die("incomplete pattern expression group: %s", p->pattern);

	if (opt->no_body_match && opt->pattern_expression)
		opt->pattern_expression = grep_not_expr(opt->pattern_expression);

	if (!header_expr)
		return;

	if (!opt->pattern_expression)
		opt->pattern_expression = header_expr;
	else if (opt->all_match)
		opt->pattern_expression = grep_splice_or(header_expr,
							 opt->pattern_expression);
	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)
{