From: Christian Ehrhardt Date: Wed, 10 Jan 2018 15:11:37 +0000 (+0100) Subject: tests: make sure rand_dev suffix has 6 chars X-Git-Tag: v4.15.0~24 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9bed02a5d576f2d3cb3c8b250d8938f4978343f3;p=thirdparty%2Fiproute2.git tests: make sure rand_dev suffix has 6 chars The change to limit the read size from /dev/urandom is a tradeoff. Reading too much can trigger an issue, but so it could if the suggested 250 random chars would not contain enough [:alpha:] chars. If they contain: a) >=6 all is ok b) [1-5] the devname would be shorter than expected (non fatal). c) 0 things would break In loops of hundreds of thousands it always was (a) for my, but since if occuring in a test it might be hard to track what happened avoid this issue by retrying on the length condition. Signed-off-by: Christian Ehrhardt Signed-off-by: Stephen Hemminger --- diff --git a/testsuite/lib/generic.sh b/testsuite/lib/generic.sh index 3645ff52d..8cef20fa1 100644 --- a/testsuite/lib/generic.sh +++ b/testsuite/lib/generic.sh @@ -87,7 +87,11 @@ ts_qdisc_available() rand_dev() { - echo "dev-$(head -c 250 /dev/urandom | tr -dc '[:alpha:]' | head -c 6)" + rnd="" + while [ ${#rnd} -ne 6 ]; do + rnd="$(head -c 250 /dev/urandom | tr -dc '[:alpha:]' | head -c 6)" + done + echo "dev-$rnd" } pr_failed()