Bug 12816

Summary:	grep does not match GNU grep for -xf EMPTY_FILE
Product:	Busybox	Reporter:	wolf+busybox
Component:	Other	Assignee:	unassigned
Status:	RESOLVED FIXED
Severity:	normal	CC:	busybox-cvs
Priority:	P5
Version:	1.32.x
Target Milestone:	---
Hardware:	All
OS:	Linux
Host:		Target:
Build:

Description wolf+busybox 2020-04-27 12:22:32 UTC

Hello,

while implementing whitelist mechanism in my shell scripting, I've
noticed an inconsistency between busybox's grep and GNU grep. They
handle -xf EMPTY_FILE flags differently when EMPTY_FILE is well...
empty.

GNU grep in that case handles it as if /.*/ pattern was provided, while
busybox uses //.

Attached patch fixes this issue. I've both added a test case into grep's
testsuite and I've also used following shell script to verify that the
behavior does match now:

http://lists.busybox.net/pipermail/busybox/2020-April/087915.html

Comment 1 Denys Vlasenko 2020-04-29 22:22:00 UTC

Fixed in git