1 files changed, 144 insertions, 0 deletions
diff --git a/re.c b/re.c
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index 00000000..3b05e6bf
--- /dev/null
+++ b/re.c
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+/*
+ * re.c - compile regular expressions.
+ */
+
+/* 
+ * Copyright (C) 1991 the Free Software Foundation, Inc.
+ * 
+ * This file is part of GAWK, the GNU implementation of the
+ * AWK Progamming Language.
+ * 
+ * GAWK is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 1, or (at your option)
+ * any later version.
+ * 
+ * GAWK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GAWK; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "awk.h"
+
+/* Generate compiled regular expressions */
+Regexp *
+make_regexp(s, ignorecase, dfa)
+NODE *s;
+int ignorecase;
+int dfa;
+{
+	Regexp *rp;
+	char *err;
+
+	emalloc(rp, Regexp *, sizeof(*rp), "make_regexp");
+	memset((char *) rp, 0, sizeof(*rp));
+	emalloc(rp->pat.buffer, char *, 16, "make_regexp");
+	rp->pat.allocated = 16;
+	emalloc(rp->pat.fastmap, char *, 256, "make_regexp");
+
+	if (ignorecase)
+		rp->pat.translate = casetable;
+	else
+		rp->pat.translate = NULL;
+	if ((err = re_compile_pattern(s->stptr, (size_t) s->stlen, &(rp->pat))) != NULL)
+		fatal("%s: /%s/", err, s->stptr);
+	if (dfa && !ignorecase) {
+		regcompile(s->stptr, s->stlen, &(rp->dfareg), 1);
+		rp->dfa = 1;
+	} else
+		rp->dfa = 0;
+	free_temp(s);
+	return rp;
+}
+
+int
+research(rp, str, len, need_start)
+Regexp *rp;
+register char *str;
+register int len;
+int need_start;
+{
+	int count;
+	int try_backref;
+	char save1;
+	char save2;
+	char *ret = &save2;
+
+	if (rp->dfa) {
+		save1 = str[len];
+		str[len] = '\n';
+		save2 = str[len+1];
+		ret = regexecute(&(rp->dfareg), str, str+len+1, 0, &count,
+					&try_backref);
+		str[len] = save1;
+		str[len+1] = save2;
+	}
+	if (ret) {
+		if (need_start || rp->dfa == 0)
+			return re_search(&(rp->pat), str, len, 0, len, &(rp->regs));
+		else
+			return 1;
+	 } else
+		return -1;
+}
+
+void
+refree(rp)
+Regexp *rp;
+{
+	free(rp->pat.buffer);
+	free(rp->pat.fastmap);
+	if (rp->dfa)
+		regfree(&(rp->dfareg));
+	free(rp);
+}
+
+void
+regerror(s)
+const char *s;
+{
+	fatal(s);
+}
+
+Regexp *
+re_update(t)
+NODE *t;
+{
+	NODE *t1;
+
+#	define	CASE	1
+	if ((t->re_flags & CASE) == IGNORECASE) {
+		if (t->re_flags & CONST)
+			return t->re_reg;
+		t1 = force_string(tree_eval(t->re_exp));
+		if (t->re_text) {
+			if (cmp_nodes(t->re_text, t1) == 0) {
+				free_temp(t1);
+				return t->re_reg;
+			}
+			unref(t->re_text);
+		}
+		t->re_text = dupnode(t1);
+		free_temp(t1);
+	}
+	if (t->re_reg)
+		refree(t->re_reg);
+	if (t->re_cnt)
+		t->re_cnt++;
+	if (t->re_cnt > 10)
+		t->re_cnt = 0;
+	if (!t->re_text) {
+		t1 = force_string(tree_eval(t->re_exp));
+		t->re_text = dupnode(t1);
+		free_temp(t1);
+	}
+	t->re_reg = make_regexp(t->re_text, IGNORECASE, t->re_cnt);
+	t->re_flags &= ~CASE;
+	t->re_flags |= IGNORECASE;
+	return t->re_reg;
+}