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| From | Uncle Steve <stevet810@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Malloc Query |
| Date | 2011-05-21 11:13 -0400 |
| Organization | Friends of the Galactic Collective |
| Message-ID | <b5cf4d9e084fa3f-1edbb@gmail.com> (permalink) |
| References | (5 earlier) <0.3ac369f64d11bcd06d18.20110519002615BST.87ei3vtwtk.fsf@bsb.me.uk> <98a074c87051012-452fb@gmail.com> <0.bf5e9ff46dfbfc1e78d6.20110519032218BST.87tycrsa3p.fsf@bsb.me.uk> <fb81382c91724d0-17e8d@gmail.com> <93omefF1bbU15@mid.individual.net> |
On Sat, May 21, 2011 at 02:30:39PM +1200, Ian Collins wrote:
> On 05/20/11 10:34 AM, Uncle Steve wrote:
>
> A couple of comments on the code:
>
> <snip>
>
> >arena_head * arena_creat(size_t s, int n)
> >{
> > arena_head * h;
> > int i;
> >
> > h = malloc(sizeof(arena_head));
> > if(h == NULL) {
> > perror("malloc()");
> > exit(1);
> > }
> >
> > h->obj_size = s;
> > h->arena_size = n;
> > h->free = n;
> >
> > h->arena = malloc(s * n);
> > if(h->arena == NULL) {
> > perror("malloc()");
> > exit(1);
> > }
> >
> > h->free_list = 0;
> >
> > for(i = 0; i< n; i++)
> > *((int *) arena_obj_addr(h, i)) = i + 1;
> >
> > *((int *) arena_obj_addr(h, i)) = -1;
>
> This writes past the end of the allocated block.
Ha, you're right. The original code this is based on doesn't have
that problem. The for(;;) comparison should be i < (n - 1). Since I
wrote it in less than an hour, there ought to be several good bugs in
there.
> > return(h);
> >}
> >
> >
> >typedef unsigned long long int T64;
> >
> >#define processcputime(p)
> >\
>
> Why go the the trouble of declaring this as a messy macro?
I'm not all that interested in nanosecond resolution for timing
things, so I scaled the resolution down to microseconds and turned it
into a 64-bit quantity so arithmetic calculations would be more
convenient. I suppose it could be a function call, but inline it
probably generates ten or so instructions. Insulating the actual
system function call also makes porting a little easier.
Regards,
Uncle Steve
--
Should a professional politician be charged with molestation if he
kisses babies while attending political rallies?
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Malloc Query Pushpa <pushpa@nospam.invalid> - 2011-05-17 19:39 +0000
Re: Malloc Query blp@cs.stanford.edu (Ben Pfaff) - 2011-05-17 12:55 -0700
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 12:05 +0100
Re: Malloc Query Pushpa <pushpa@nospam.invalid> - 2011-05-18 17:11 +0000
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:42 +0100
Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-18 21:10 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-18 19:34 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-18 17:10 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 00:26 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-18 21:25 -0400
Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-18 21:38 -0400
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 14:11 -0400
Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-19 22:55 -0400
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 12:14 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 03:22 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 14:20 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 23:51 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 20:01 -0400
Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-22 02:49 -0700
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 10:46 -0400
Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-22 12:37 -0500
Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-22 13:02 -0500
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 14:12 -0400
Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-23 03:06 -0500
Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-23 00:42 -0700
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 11:10 -0400
Re: Malloc Query Keith Thompson <kst-u@mib.org> - 2011-05-23 09:06 -0700
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-22 23:18 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 19:18 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-23 11:22 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 01:57 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-23 19:24 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 14:20 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 07:41 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 16:24 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 09:20 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 18:05 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 10:37 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 19:34 -0400
Re: Malloc Query "robertwessel2@yahoo.com" <robertwessel2@yahoo.com> - 2011-05-23 17:48 -0700
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 12:56 +1200
Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-24 07:19 -0400
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-24 11:32 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-23 01:04 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 02:36 -0400
Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-23 00:39 -0700
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-23 14:44 +0100
Re: Malloc Query Seebs <usenet-nospam@seebs.net> - 2011-05-23 15:16 +0000
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 11:41 -0400
Re: Malloc Query David Thompson <dave.thompson2@verizon.net> - 2011-06-01 16:33 -0400
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 18:34 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-20 02:36 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 12:26 -0400
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-20 23:32 +0100
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 21:17 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-21 14:30 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-21 11:13 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-22 08:50 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-21 20:03 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-22 13:23 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 10:01 -0400
Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-26 08:12 +0200
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-26 19:16 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 15:03 -0400
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-27 09:16 +1200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 17:55 -0400
Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-27 05:47 +0200
Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 15:02 -0400
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:31 +0100
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-18 23:37 +0100
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 01:50 +0100
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 02:50 +0100
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 12:14 +0100
Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 15:10 +0100
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 15:48 +0100
Re: Malloc Query cri@tiac.net (Richard Harter) - 2011-05-18 19:31 +0000
Re: Malloc Query Ike Naar <ike@iceland.freeshell.org> - 2011-05-18 21:43 +0000
Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:58 +0100
Re: Malloc Query Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-05-17 14:01 -0600
Re: Malloc Query Columbus sailed the ocean China Blue <chine.bleu@yahoo.com> - 2011-05-17 13:21 -0700
Re: Malloc Query BGB <cr88192@hotmail.com> - 2011-05-17 14:08 -0700
Re: Malloc Query Michael Press <rubrum@pacbell.net> - 2011-05-17 19:49 -0700
Re: Malloc Query Lauri Alanko <la@iki.fi> - 2011-05-18 00:50 +0000
Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-17 21:21 -0400
Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-18 19:31 +0200
Re: Malloc Query Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-18 21:36 +0000
Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-18 21:26 -0400
Re: Malloc Query Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-19 02:07 -0700
Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-19 21:13 +1200
Re: Malloc Query Nobody <nobody@nowhere.com> - 2011-05-18 07:08 +0100
Re: Malloc Query David Resnick <lndresnick@gmail.com> - 2011-05-19 07:51 -0700
Re: Malloc Query Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-05-19 09:12 -0600
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