comp.lang.ada
 help / color / mirror / Atom feed
From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Subject: Re: is there a version of unix written in Ada
Date: Thu, 1 Oct 2020 14:38:27 +0300	[thread overview]
Message-ID: <htltdlFel31U1@mid.individual.net> (raw)
In-Reply-To: <rl4ajp$1d9d$1@gioia.aioe.org>

On 2020-10-01 13:21, Dmitry A. Kazakov wrote:
> On 01/10/2020 11:59, J-P. Rosen wrote:
>> Le 01/10/2020 à 11:28, Dmitry A. Kazakov a écrit :
>>> BTW, I still do not know to design an Ada-conform tracing/logging
>>> facility such that you could trace/log from anywhere, protected action
>>> included, and without knowing statically which protected object is
>>> involved.
>>>
>> Did you have a look at package Debug?
>> (https://www.adalog.fr/en/components#Debug)
> 
> Thanks
> 
>> It features, among others, a trace routine which is guaranteed to not be
>> potentially blocking.
> 
> It calls a protected operation on a different protected object, yes, 
> this is non-blocking, and I considered same, but is this legal?


Yes.

If the program is using ceiling-priority-based protection, the priority 
of the calling object must be less or equal to the priority of the 
called object.


> Or is that limited to protected entries only?


An entry call is potentially blocking and therefore not allowed in a 
protected operation.


> Another issue is having two different calls: Trace and protected Trace. 
> If one used instead of another, you have a ticking bomb in the 
> production code.


I assume that is a "feature" of the referenced Debug package, not of the 
basic method it uses to implement a logging facility.

I haven't looked at the Debug package, but I would have suggested a 
logging facility that consists of:

1. A LIFO queue of log entries implemented in a protected object of 
highest priority. The object has a procedure "Write_Log_Entry".

2. A task that empties the LIFO queue into a log file. The task calls an 
entry of the LIFO protected object to get a log entry from the queue, 
but executes the file-writing operations in task context, not in a 
protected operation.

  reply	other threads:[~2020-10-01 11:38 UTC|newest]

Thread overview: 105+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <e3c51e65-b71e-4623-bd58-c94cdbcc3ba6o@googlegroups.com>
2020-07-25  7:37 ` is there a version of unix written in Ada mockturtle
2020-07-26 19:45   ` Stéphane Rivière
2020-07-26 22:15     ` Jeffrey R. Carter
2020-07-27  7:40       ` Stéphane Rivière
2020-07-28 13:08       ` DrPi
2020-07-28 16:48         ` Simon Wright
2020-07-28 17:00           ` Fabien Chouteau
2020-07-29  9:21             ` DrPi
2020-07-29  9:28               ` Fabien Chouteau
2020-07-29 15:02                 ` DrPi
2020-07-29 15:11                   ` Fabien Chouteau
2020-07-29 20:41                     ` DrPi
2020-07-29  9:20           ` DrPi
2020-07-29 16:53             ` Simon Wright
2020-07-29 20:42               ` DrPi
2020-07-25  8:47 ` Niklas Holsti
2020-07-25  9:36   ` Stéphane Rivière
2020-07-25 10:41 ` Luke A. Guest
2020-07-25 14:43 ` Jesper Quorning
2020-07-25 19:20 ` Andreas ZEURCHER
2020-07-27  7:40   ` Stéphane Rivière
2020-07-27 15:00     ` nobody in particular
2020-07-27 14:58   ` nobody in particular
2020-07-27 20:28 ` Shark8
2020-07-30  0:57 ` gdotone
2020-07-31 14:01   ` Shark8
2020-09-23 17:39   ` Olivier Henley
2020-09-25 15:06     ` DrPi
2020-09-25 17:31       ` Andreas ZEURCHER
2020-09-26  8:50         ` DrPi
2020-09-27 18:55           ` Luke A. Guest
2020-09-27 19:07             ` Luke A. Guest
2020-09-27 18:53         ` Luke A. Guest
2020-09-27 14:25     ` Shark8
2020-09-27 15:01       ` Dmitry A. Kazakov
2020-09-27 20:59         ` DrPi
2020-09-28  7:41           ` Dmitry A. Kazakov
2020-09-28 13:48             ` Olivier Henley
2020-09-28 14:48               ` Dmitry A. Kazakov
2020-09-28 16:28                 ` Olivier Henley
2020-09-28 20:30                   ` Dmitry A. Kazakov
2020-09-28 21:06                     ` Shark8
2020-09-28 17:47                 ` Paul Rubin
2020-09-28 20:27                   ` Dmitry A. Kazakov
2020-09-29 23:54                     ` Paul Rubin
2020-09-30  8:18                       ` Dmitry A. Kazakov
2020-09-30 17:27                         ` Paul Rubin
2020-09-30 19:42                           ` Dmitry A. Kazakov
2020-09-30 20:33                             ` Paul Rubin
2020-09-30 21:03                               ` Dmitry A. Kazakov
2020-09-30 22:42                                 ` Randy Brukardt
2020-10-01  9:28                                   ` Dmitry A. Kazakov
2020-10-01  9:59                                     ` J-P. Rosen
2020-10-01 10:21                                       ` Dmitry A. Kazakov
2020-10-01 11:38                                         ` Niklas Holsti [this message]
2020-10-01 11:52                                           ` Niklas Holsti
2020-10-01 12:51                                           ` Dmitry A. Kazakov
2020-10-01 14:18                                             ` J-P. Rosen
2020-10-01 15:44                                               ` Dmitry A. Kazakov
2020-10-01 22:10                                                 ` Randy Brukardt
2020-10-02  5:36                                                 ` J-P. Rosen
2020-10-02  6:56                                                   ` Dmitry A. Kazakov
2020-10-02  7:42                                                     ` J-P. Rosen
2020-10-03  3:14                                                       ` Randy Brukardt
2020-10-01 15:38                                             ` Niklas Holsti
2020-10-01 16:06                                               ` Dmitry A. Kazakov
2020-10-01 17:01                                                 ` Niklas Holsti
2020-10-01 17:37                                                   ` Dmitry A. Kazakov
2020-10-01 22:13                                                 ` Randy Brukardt
2020-10-01 11:48                                         ` J-P. Rosen
2020-10-01 12:54                                           ` Dmitry A. Kazakov
2020-10-01  7:57                                 ` Paul Rubin
2020-10-01  9:26                                   ` Dmitry A. Kazakov
2020-10-01  9:46                                     ` Paul Rubin
2020-10-01 10:35                                       ` Dmitry A. Kazakov
2020-10-01 19:02                                       ` DrPi
2020-10-01 23:12                                         ` Paul Rubin
2020-10-01 21:54                                       ` Randy Brukardt
2020-10-01 23:14                                         ` Paul Rubin
2020-10-01 21:36                             ` Brian Drummond
2020-10-02  6:56                               ` Dmitry A. Kazakov
2020-10-02 18:34                                 ` Brian Drummond
2020-10-02 21:24                                   ` Paul Rubin
2020-10-06 23:54                                     ` Brian Drummond
2020-10-03  6:54                                   ` Dmitry A. Kazakov
2020-10-05 14:03                               ` Shark8
2020-10-07 11:56                               ` Olivier Henley
2020-10-09 12:35                               ` Olivier Henley
2020-10-09 14:41                                 ` Brian Drummond
2020-09-28 18:40                 ` Vincent Marciante
2020-09-28 20:28                   ` Dmitry A. Kazakov
2020-09-28 17:04               ` DrPi
2020-09-28 17:30                 ` Olivier Henley
2020-09-28 18:05                   ` Olivier Henley
2020-09-28 19:36               ` Shark8
2020-09-03 10:32 ` c+
2020-09-12  4:30 ` sumde121
2020-09-19 14:09 ` erchetan33
2020-10-01 22:21 Randy Brukardt
2020-10-02  6:55 ` Dmitry A. Kazakov
2020-10-03  3:09   ` Randy Brukardt
2020-10-03  6:42     ` Dmitry A. Kazakov
2020-10-03  7:44       ` Niklas Holsti
2020-10-03  8:16         ` Dmitry A. Kazakov
2020-10-03 10:44           ` Niklas Holsti
replies disabled

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox