From 5579176f4a885bb83119bb49598c357ce8db2343 Mon Sep 17 00:00:00 2001
From: Ori Bernstein <ori@eigenstate.org>
Date: Sat, 25 Jun 2022 18:58:55 +0000
Subject: [PATCH] awk: initialize records fully in recinit()

when using records in BEGIN, we would read
from the field table before we read into it;
this ensures that the fields are an empty
string before we start touching their contents.
---
 sys/src/cmd/awk/lib.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/sys/src/cmd/awk/lib.c b/sys/src/cmd/awk/lib.c
index 2c5a60465..5044d3123 100644
--- a/sys/src/cmd/awk/lib.c
+++ b/sys/src/cmd/awk/lib.c
@@ -54,11 +54,13 @@ static Cell dollar1 = { OCELL, CFLD, nil, "", 0.0, FLD|STR|DONTFREE };
 
 void recinit(unsigned int n)
 {
+	assert(n > 0);
 	record = (char *) malloc(n);
 	fields = (char *) malloc(n);
 	fldtab = (Cell **) malloc((nfields+1) * sizeof(Cell *));
 	if (record == nil || fields == nil || fldtab == nil)
 		FATAL("out of space for $0 and fields");
+	record[0] = '\0';
 	fldtab[0] = (Cell *) malloc(sizeof (Cell));
 	*fldtab[0] = dollar0;
 	fldtab[0]->sval = record;
@@ -108,7 +110,7 @@ int getrec(char **pbuf, int *pbufsize, int isrecord)	/* get next input record */
 		firsttime = 0;
 		initgetrec();
 	}
-	   dprint( ("RS=<%s>, FS=<%s>, AARGC=%g, FILENAME=%s\n",
+ 	dprint( ("RS=<%s>, FS=<%s>, AARGC=%g, FILENAME=%s\n",
 		*RS, *FS, *AARGC, *FILENAME) );
 	if (isrecord) {
 		donefld = 0;