Commands `sort` and `shuf` have a "--random-source" argument. That's useful for generating stable, reproducible "random" output. However, we want to do this based on a fixed seed, while the "--random-source" expects a stream of randomness. Add a helper script for that. Also, use the stable randomness for shuf in the test "tests/shell/testcases/sets/automerge_0". See-also: https://www.gnu.org/software/coreutils/manual/html_node/Random-sources.html#Random-sources Signed-off-by: Thomas Haller <thaller@xxxxxxxxxx> --- tests/shell/helpers/random-source.sh | 40 ++++++++++++++++++++++++++ tests/shell/testcases/sets/automerge_0 | 2 +- 2 files changed, 41 insertions(+), 1 deletion(-) create mode 100755 tests/shell/helpers/random-source.sh diff --git a/tests/shell/helpers/random-source.sh b/tests/shell/helpers/random-source.sh new file mode 100755 index 000000000000..91a8248bea1f --- /dev/null +++ b/tests/shell/helpers/random-source.sh @@ -0,0 +1,40 @@ +#!/bin/bash + +# Commands like `sort` and `shuf` have a "--random-source" argument, for +# generating a stable, reproducible output. However, they require an input +# that provides sufficiently many bytes (depending on the input). +# +# This script generates a stream that can be used like +# +# shuf --random-source=<($0 "$seed") + +seed="" +for a; do + seed="$seed${#a}:$a\n" +done + +if command -v openssl &>/dev/null ; then + # We have openssl. Use it. + # https://www.gnu.org/software/coreutils/manual/html_node/Random-sources.html#Random-sources + # + # Note that we don't care that different installations/architectures generate the + # same output. + openssl enc -aes-256-ctr -pass "pass:$seed" -nosalt </dev/zero 2>/dev/null +else + # Hack something. It's much slower. + idx=0 + while : ; do + idx="$((idx++))" + seed="$(sha256sum <<<"$idx.$seed")" + echo ">>>$seed" >> a + seed="${seed%% *}" + LANG=C awk -v s="$seed" 'BEGIN{ + for (i=1; i <= length(s); i+=2) { + xchar = substr(s, i, 2); + decnum = strtonum("0x"xchar); + printf("%c", decnum); + } + }' || break + done +fi +exit 0 diff --git a/tests/shell/testcases/sets/automerge_0 b/tests/shell/testcases/sets/automerge_0 index 170c38651de0..1dbac0b7cdbd 100755 --- a/tests/shell/testcases/sets/automerge_0 +++ b/tests/shell/testcases/sets/automerge_0 @@ -44,7 +44,7 @@ do done tmpfile3=$(mktemp) -shuf $tmpfile2 > $tmpfile3 +shuf "$tmpfile2" --random-source=<("$NFT_TEST_BASEDIR/helpers/random-source.sh" "automerge-shuf-tmpfile2" "$NFT_TEST_RANDOM_SEED") > "$tmpfile3" i=0 cat $tmpfile3 | while read line && [ $i -lt 10 ] do -- 2.41.0
