Correctly reset the goto table for a state.

We cannot use set_gototab() to reset all the entries for a state,
it will leave existing entries as-is.  Add a new reset_gototab()
function that zeroes the table entries for the specified state.
There is no need to reset the goto table immediately after
resize_state(), it is already initialized via calloc().
Fixes https://github.com/onetrueawk/awk/issues/199

diff --git a/usr.bin/awk/b.c b/usr.bin/awk/b.c
index 2370c66..6706137 100644 (file)
--- a/usr.bin/awk/b.c
+++ b/usr.bin/awk/b.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: b.c,v 1.43 2023/10/06 22:29:24 millert Exp $  */
+/*     $OpenBSD: b.c,v 1.44 2023/10/06 22:31:21 millert Exp $  */
 /****************************************************************
 Copyright (C) Lucent Technologies 1997
 All Rights Reserved
@@ -116,6 +116,7 @@ extern int u8_nextlen(const char *s);
 
 static int get_gototab(fa*, int, int);
 static int set_gototab(fa*, int, int, int);
+static void reset_gototab(fa*, int);
 extern int u8_rune(int *, const uschar *);
 
 static int *
@@ -276,8 +277,7 @@ int makeinit(fa *f, bool anchor)
        }
        if ((f->posns[2])[1] == f->accept)
                f->out[2] = 1;
-       for (i = 0; i < NCHARS; i++)
-               set_gototab(f, 2, 0, 0); /* f->gototab[2][i] = 0; */
+       reset_gototab(f, 2);
        f->curstat = cgoto(f, 2, HAT);
        if (anchor) {
                *f->posns[2] = k-1;     /* leave out position 0 */
@@ -613,6 +613,11 @@ static int get_gototab(fa *f, int state, int ch) /* hide gototab inplementation
        return 0;
 }
 
+static void reset_gototab(fa *f, int state) /* hide gototab inplementation */
+{
+       memset(f->gototab[state], 0, f->gototab_len * sizeof(**f->gototab));
+}
+
 static int set_gototab(fa *f, int state, int ch, int val) /* hide gototab inplementation */
 {
        int i;
@@ -1492,8 +1497,6 @@ int cgoto(fa *f, int s, int c)
        /* add tmpset to current set of states */
        ++(f->curstat);
        resize_state(f, f->curstat);
-       for (i = 0; i < NCHARS; i++)
-               set_gototab(f, f->curstat, 0, 0);
        xfree(f->posns[f->curstat]);
        p = intalloc(setcnt + 1, __func__);