From a6a92037b56f4fad9c75409f2b9ee89555c8c54c Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sun, 9 Mar 2014 21:25:51 -0700
Subject: [PATCH] tests: make a perf.-related test less system-sensitive

Andreas Schwab reported in http://debbugs.gnu.org/16941
that this test would timeout on m68k-suse-linux.
Rather than testing absolute duration with a limit tuned
to today's hardware, compare performance of grep with LC_ALL=C
against that same command using LC_ALL=ja_JP.eucJP.
* tests/init.cfg (require_hi_res_time_): New function.
* tests/mb-non-UTF8-performance: Rewrite to use it:
record absolute duration D of the first (normally much faster)
command, and set a timeout of 8*D for the command running in
an affected locale.
---
 tests/init.cfg                | 15 +++++++++++++++
 tests/mb-non-UTF8-performance | 17 ++++++++++++++---
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/tests/init.cfg b/tests/init.cfg
index 5555e2d..3e9ab03 100644
--- a/tests/init.cfg
+++ b/tests/init.cfg
@@ -103,6 +103,21 @@ require_unibyte_locale()
   skip_ 'no unibyte locale found'
 }

+# Define hi_res_time_ to a function that prints the current time
+# as a floating point number with greater than 1-second resolution.
+# Otherwise, skip the requiring test.
+require_hi_res_time_()
+{
+  local cmd
+  for cmd in 'date +%s.%N' \
+          'perl -le "use Time::HiRes qw(time); print scalar time()"'; do
+      case $($cmd) in
+          *.[0-9]*) eval 'hi_res_time_() { '"$cmd"'; }'; break;;
+      esac
+  done
+  type hi_res_time_ || skip_ no high-resolution timer support
+}
+
 require_JP_EUC_locale_()
 {
   local locale=ja_JP.eucJP
diff --git a/tests/mb-non-UTF8-performance b/tests/mb-non-UTF8-performance
index 282f0c4..640d5db 100755
--- a/tests/mb-non-UTF8-performance
+++ b/tests/mb-non-UTF8-performance
@@ -18,15 +18,26 @@

 . "${srcdir=.}/init.sh"; path_prepend_ ../src
 require_timeout_
+require_hi_res_time_

 fail=0

-require_JP_EUC_locale_
-
 yes $(printf '%078d' 0) | head -50000 > in || framework_failure_

+start=$(hi_res_time_)
+LC_ALL=C grep -i foobar in; st=$?
+stop=$(hi_res_time_)
+
+# Use a multiple of the LC_ALL=C duration as the timeout for the JP/EUC test.
+# Typically, a multiple of 3 seems to be enough.
+timeout=$($AWK 'BEGIN { print 8 * ('$stop' - '$start')}' < /dev/null)
+
+test $st = 1 || fail=1
+
+require_JP_EUC_locale_
+
 # Expect no match, i.e., exit status of 1.  Anything else is an error.
-timeout 4 grep -i foobar in; st=$?
+timeout $timeout grep -i foobar in; st=$?
 test $st = 1 || fail=1

 Exit $fail
-- 
1.9.0.152.g6ab4ae2