[CRIU] [PATCH 1/2] test: replace cat in Makefiles with awk

[Dmitry Safonov]

2017-01-12 11:20 GMT+03:00 Dmitry Safonov <0x7f454c46 at gmail.com>:
> 2017-01-12 9:27 GMT+03:00 Vitaly Ostrosablin <vostrosablin at virtuozzo.com>:
>> cat *.pid works when we have only one running process at any moment.
>> That's because pidfiles contain no newlines and cat will just
>> concatenate content of all files present in directory. So, e.g., if we
>> have pidfiles:
>>
>> 31338
>> 31359
>> 31880
>> 31884
>> 31889
>>
>> cat will build following string from those pidfiles:
>>
>> 3133831359318803188431889
>
> I don't mind the patch, but your explanation looks obiviously wrong:
> [test]$ echo 123 > 1.txt
> [test]$ echo 456 > 2.txt
> [test]$ cat *.txt
> 123
> 456
> [test]$ cat Makefile
> all:
>     cat *.txt
> [test]$ make
> cat *.txt
> 123
> 456

[test]$ cat Makefile
all:
    echo `cat *.txt`
[test]$ make
echo `cat *.txt`
123 456
[test]$

>
> Is it something that depends on environment, like ${IFS} in bash?
> Check, please.
>
>>
>> Obviously, kill would fail to send signals to processes, because it's
>> now a single big number, which cannot be unambigously split back in
>> general case.
>>
>> That's where awk comes in. We don't need to modify C part of tests to
>> print newlines at end of file. We just order awk to print content of
>> each file, which adds a newline at end - problem solved, kill can once
>> again parse, which PIDs it get and send proper signals to them. Also,
>> should be completely safe for zdtm.py, because it doesn't use Makefiles
>> and sends signals on it's own.
>> ---
>>  test/zdtm/static/Makefile     | 4 ++--
>>  test/zdtm/transition/Makefile | 4 ++--
>>  2 files changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/test/zdtm/static/Makefile b/test/zdtm/static/Makefile
>> index af1254f5..8fe9d953 100644
>> --- a/test/zdtm/static/Makefile
>> +++ b/test/zdtm/static/Makefile
>> @@ -338,7 +338,7 @@ start:      $(PID) $(STATE)
>>  check_start:   $(PID:%.pid=%.is_running)
>>
>>  stop:  $(STATE_OUT)
>> -       -kill -TERM `cat *.pid`
>> +       -kill -TERM `awk '{print}' *.pid`
>>
>>  WAIT_TIME=240
>>  %.stop:        %.pid %
>> @@ -356,7 +356,7 @@ WAIT_TIME=240
>>  wait_stop:
>>                 i=0; \
>>                 while [ $$i -lt $(WAIT_TIME) ] ; do \
>> -               kill -0 `cat *.pid 2>/dev/null` 2>/dev/null || break; \
>> +               kill -0 `awk '{print}' *.pid 2>/dev/null` 2>/dev/null || break; \
>>                 sleep 1; \
>>                 i=`expr $$i + 1`; \
>>         done
>> diff --git a/test/zdtm/transition/Makefile b/test/zdtm/transition/Makefile
>> index 7ddb2384..dfc10ef5 100644
>> --- a/test/zdtm/transition/Makefile
>> +++ b/test/zdtm/transition/Makefile
>> @@ -65,12 +65,12 @@ start:      $(PID)
>>  check_start:   $(PID:%.pid=%.is_running)
>>
>>  stop:
>> -       -kill -TERM `cat *.pid`
>> +       -kill -TERM `awk '{print}' *.pid`
>>
>>  WAIT_TIME=10
>>  wait_stop:
>>         -for i in `seq 1 $(WAIT_TIME)`; do \
>> -               kill -0 `cat *.pid 2>/dev/null` 2>/dev/null || break; \
>> +               kill -0 `awk '{print}' *.pid 2>/dev/null` 2>/dev/null || break; \
>>                 sleep 1; \
>>         done
>>
>> --
>> 2.11.0
>>
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>> CRIU at openvz.org
>> https://lists.openvz.org/mailman/listinfo/criu
>
>
>
> --
>              Dmitry



-- 
             Dmitry