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* TODO: New file.

Browse source 
* attach.c, mcalloc.c, mfree.c, mmalloc.c, mmalloc.h, mmap-sup.c,
	mmcheck.c, mtrace.c, mrealloc.c, mvalloc.c, sbrk-sup.c:  Lint.
This commit is contained in:
Fred Fish 1992-04-17 03:01:54 +00:00
parent 2d6d969c61
commit 13b33d2b0a
2 changed files with 84 additions and 0 deletions
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15
mmalloc/TODO Normal file
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(1) Make implementation changes necessary to allow multiple processes
to use the mmalloc managed region simultaneously. This requires,
at the minimum, some sort of cooperative locking that ensures that
only one process at a time is changing any of the mmalloc managed
data structures (its ok for the mmalloc managed data regions to be
changed at any time since we don't care about their contents).
(2) In order to support multiple processes using the mmalloc managed
region, the malloc descriptor needs to be broken into two parts,
one part which is specific to the given process and is maintained
separately on a per process basis, and another part which is common
to all processes. As an example, the file descriptor is specific
to a given process, as are the morecore and abortfunc pointers.
However magic[], the version number, the flags field, etc are
common to all processes.

69
mmalloc/sbrk-sup.c Normal file
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/* Support for sbrk() regions.
Copyright 1992 Free Software Foundation, Inc.
Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <string.h> /* Prototypes for memcpy, memmove, memset, etc */
#include "mmalloc.h"
extern PTR sbrk ();
/* The mmalloc() package can use a single implicit malloc descriptor
for mmalloc/mrealloc/mfree operations which do not supply an explicit
descriptor. For these operations, sbrk() is used to obtain more core
from the system, or return core. This allows mmalloc() to provide
backwards compatibility with the non-mmap'd version. */
struct mdesc *__mmalloc_default_mdp;
/* Use sbrk() to get more core. */
static PTR
sbrk_morecore (mdp, size)
struct mdesc *mdp;
int size;
{
PTR result;
if ((result = sbrk (size)) != NULL)
{
mdp -> breakval += size;
mdp -> top += size;
}
return (result);
}
/* Initialize the default malloc descriptor if this is the first time
a request has been made to use the default sbrk'd region. */
struct mdesc *
__mmalloc_sbrk_init ()
{
PTR base;
base = sbrk (0);
__mmalloc_default_mdp = (struct mdesc *) sbrk (sizeof (struct mdesc));
(void) memset ((char *) __mmalloc_default_mdp, 0, sizeof (struct mdesc));
__mmalloc_default_mdp -> morecore = sbrk_morecore;
__mmalloc_default_mdp -> base = base;
__mmalloc_default_mdp -> breakval = __mmalloc_default_mdp -> top = sbrk (0);
__mmalloc_default_mdp -> fd = -1;
return (__mmalloc_default_mdp);
}