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From: Sam <sah@softcardsystems.com>
To: <9fans@cse.psu.edu>
Subject: Re: [9fans] how to avoid a memset() optimization
Date: Mon,  6 Jan 2003 10:42:07 -0500	[thread overview]
Message-ID: <Pine.LNX.4.30.0301061034040.19189-100000@athena> (raw)
In-Reply-To: <3afa.3e16dd11.67d1a@blake.inputplus.co.uk>

or:

{
	int m=0;

	if(++m && (res1 = lock(A)))
	if(++m && (res2 = lock(B)))
	if(++m && (res3 = lock(C))) {
		foo();
		return success;
	}
	switch(m) {
	case 3:	 release(B);
	case 2:  release(A);
	default: return failure;
	}
}

you just need a marker to see how far you got. (I'm not even sure
what the context of this message is, but every time i see the goto
solution to this I have to say something). ;)

Cheers,

Sam

>
>         failed = 1;
>
>         if ((res1 = lock(A) == 0) {
>             goto releaseA;
>         }
>         if ((res2 = lock(B) == 0) {
>             goto releaseB;
>         }
>         if ((res3 = lock(C) == 0) {
>             goto releaseC;
>         }
>
>         foo(res1, res2, res3);
>         failed = 0;
>
>     releaseC:
>         release(C);
>     releaseB:
>         release(B);
>     releaseA:
>         release(A);
>
>         return failed;
>
> Cheers,
>
>





  reply	other threads:[~2003-01-06 15:42 UTC|newest]

Thread overview: 92+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-11-14 16:47 presotto
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-15 16:51   ` William Josephson
2002-11-18 10:38     ` Douglas A. Gwyn
2002-11-18 12:34       ` Ronald G. Minnich
2002-11-19  7:38 ` Roman V. Shaposhnick
2002-11-20  9:47   ` Douglas A. Gwyn
2002-11-21 20:55     ` Roman V. Shaposhnick
2002-11-22  9:59       ` Douglas A. Gwyn
2003-01-06 10:18   ` Ralph Corderoy
2003-01-06 15:42     ` Sam [this message]
2003-01-06 15:49       ` Russ Cox
2003-01-06 15:58         ` David Presotto
2003-01-06 16:02         ` Sam
2003-01-06 15:58     ` [9fans] Fs Kernel Conor Williams
  -- strict thread matches above, loose matches on Subject: below --
2003-01-06 10:47 [9fans] how to avoid a memset() optimization nigel
2003-01-06 11:15 ` Geoff Collyer
2002-11-19 14:32 presotto
2002-11-20  7:24 ` Tomas
2002-11-20 16:38   ` Douglas A. Gwyn
2002-11-19  8:21 Fco.J.Ballesteros
2002-11-18 21:36 Joel Salomon
2002-11-18 20:42 Andrew Simmons
2002-11-18 14:19 C H Forsyth
2002-11-15  1:56 Dennis Ritchie
2002-11-15 10:51 ` Douglas A. Gwyn
2002-11-15 12:03 ` Boyd Roberts
2002-11-14 18:55 jmk
2002-11-14 22:23 ` Steve Kilbane
2002-11-14 18:17 presotto
2002-11-14 18:11 Joel Salomon
2002-11-14 18:26 ` William Josephson
2002-11-14 17:44 rog
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-14 17:28 Russ Cox
     [not found] <nemo@plan9.escet.urjc.es>
2002-11-14 15:38 ` Fco.J.Ballesteros
2002-11-14 16:24   ` Scott Schwartz
2002-11-14  6:53 Russ Cox
2002-11-14 10:22 ` Douglas A. Gwyn
2002-11-14 13:20   ` Sam
2002-11-14 15:20     ` Scott Schwartz
2002-11-14 15:26       ` Boyd Roberts
2002-11-14 15:34         ` plan9
2002-11-14 15:59           ` Sam
2002-11-14 18:57         ` Steve Kilbane
2002-11-15 10:51           ` Douglas A. Gwyn
2002-11-14 15:50       ` Dan Cross
2002-11-14 17:21         ` Douglas A. Gwyn
2002-11-14 18:51           ` Dan Cross
2002-11-14 15:50     ` Douglas A. Gwyn
2002-11-19  7:20 ` Roman V. Shaposhnick
2002-11-14  2:48 Dennis Ritchie
2002-11-14  4:23 ` Ronald G. Minnich
2002-11-13 18:58 Rob `Commander' Pike
2002-11-13 14:40 C H Forsyth
2002-11-13 15:54 ` rob pike
2002-11-13 16:05   ` andrey mirtchovski
2002-11-13 16:32   ` Ronald G. Minnich
2002-11-14 10:21     ` Douglas A. Gwyn
2002-11-14 17:07       ` Ronald G. Minnich
2002-11-22  9:59     ` Clint Olsen
2002-11-13 16:56   ` William K. Josephson
2002-11-14 10:21     ` Douglas A. Gwyn
2002-11-14 16:48       ` William Josephson
2002-11-14 10:21   ` Douglas A. Gwyn
2002-11-14 14:46     ` Dan Cross
2002-11-14 16:59       ` Douglas A. Gwyn
2002-11-14 18:31         ` Tad Hunt
2002-11-15 10:50           ` Douglas A. Gwyn
2002-11-18 14:27         ` Aharon Robbins
2002-11-13 14:14 Skip Tavakkolian
2002-11-13 13:55 rog
2002-11-13 13:38 Skip Tavakkolian
2002-11-13 16:25 ` Boyd Roberts
2002-11-13 10:43 C H Forsyth
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-13  6:52 Geoff Collyer
2002-11-13 10:13 ` Boyd Roberts
2002-11-13  6:34 Andrew Simmons
2002-11-13  6:43 ` Doc Shipley
2002-11-13  1:47 Russ Cox
2002-11-13 10:16 ` Douglas A. Gwyn
2002-11-14  1:46 ` Roman V. Shaposhnick
2002-11-14  1:52   ` William Josephson
2002-11-14  6:42     ` Roman V. Shaposhnick
2002-11-13  0:31 Russ Cox
2002-11-13  1:26 ` Roman V. Shaposhnick
2002-11-13 10:15   ` Douglas A. Gwyn
2002-11-14  1:42     ` Roman V. Shaposhnick
2002-11-13 10:15 ` Douglas A. Gwyn
2002-11-13  0:20 presotto
2002-11-12 22:42 Roman V. Shaposhnick

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