Fix readrec's definition of a record

It is not sufficient to check for the EOF flag on a stream.
From https://github.com/onetrueawk/awk/pull/117

diff --git a/usr.bin/awk/lib.c b/usr.bin/awk/lib.c
index 6ae55da..cd84399 100644 (file)
--- a/usr.bin/awk/lib.c
+++ b/usr.bin/awk/lib.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: lib.c,v 1.45 2021/04/19 14:08:55 millert Exp $        */
+/*     $OpenBSD: lib.c,v 1.46 2021/06/10 21:01:43 millert Exp $        */
 /****************************************************************
 Copyright (C) Lucent Technologies 1997
 All Rights Reserved
@@ -240,6 +240,7 @@ int readrec(char **pbuf, int *pbufsize, FILE *inf, bool newflag)    /* read one rec
                }
                if (found)
                        setptr(patbeg, '\0');
+               isrec = (found == 0 && *buf == '\0') ? 0 : 1;
        } else {
                if ((sep = *rs) == 0) {
                        sep = '\n';
@@ -269,10 +270,10 @@ int readrec(char **pbuf, int *pbufsize, FILE *inf, bool newflag)  /* read one rec
                if (!adjbuf(&buf, &bufsize, 1+rr-buf, recsize, &rr, "readrec 3"))
                        FATAL("input record `%.30s...' too long", buf);
                *rr = 0;
+               isrec = (c == EOF && rr == buf) ? 0 : 1;
        }
        *pbuf = buf;
        *pbufsize = bufsize;
-       isrec = *buf || !feof(inf);
        DPRINTF("readrec saw <%s>, returns %d\n", buf, isrec);
        return isrec;
 }