[PATCH] t5562: do not depend on /dev/zero

[Max Kirillov <max@max630.net>]

It was reported [1] that NonStop platform does not have /dev/zero.

The test uses /dev/zero as a dummy input. Passing case (http-backed
failed because of too big input size) should not be reading anything
from it. If http-backend would erroneously try to read any data
returning EOF probably would be even safer than providing some
meaningless data.

Replace /dev/zero with /dev/null to avoid issues with platforms which do
not have /dev/zero.

[1] https://public-inbox.org/git/20190209185930.5256-4-randall.s.becker@rogers.com/

Reported-by: Randall S. Becker <rsbecker@nexbridge.com>
Signed-off-by: Max Kirillov <max@max630.net>
---
By the way, I don't think this requires such sofisticated
fix. In the success case the input would not be read at all.
You could replace it with /dev/null, the in failure (not 
immediate fail) git would fail due to truncated input or
something.

Also, as you experience hang issue [2] in earlier tests, this 
one should not have contributed to it.

[2] https://public-inbox.org/git/001901d4c22b$194bfe60$4be3fb20$@nexbridge.com/
 t/t5562-http-backend-content-length.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t5562-http-backend-content-length.sh b/t/t5562-http-backend-content-length.sh
index 90d890d02f..436c261c86 100755
--- a/t/t5562-http-backend-content-length.sh
+++ b/t/t5562-http-backend-content-length.sh
@@ -150,7 +150,7 @@ test_expect_success 'CONTENT_LENGTH overflow ssite_t' '
 		GIT_HTTP_EXPORT_ALL=TRUE \
 		REQUEST_METHOD=POST \
 		CONTENT_LENGTH="$NOT_FIT_IN_SSIZE" \
-		git http-backend </dev/zero >/dev/null 2>err &&
+		git http-backend </dev/null >/dev/null 2>err &&
 	grep "fatal:.*CONTENT_LENGTH" err
 '
 
-- 
2.19.0.1202.g68e1e8f04e