mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-15 04:31:49 +08:00
72 lines
2.0 KiB
C
72 lines
2.0 KiB
C
/* Finish access to a mmap'd malloc managed region.
|
|
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 <fcntl.h>
|
|
#include "mmalloc.h"
|
|
|
|
/* Terminate access to a mmalloc managed region by unmapping all memory pages
|
|
associated with the region, and closing the file descriptor if it is one
|
|
that we opened.
|
|
|
|
Returns NULL on success.
|
|
|
|
Returns the malloc descriptor on failure, which can subsequently be used
|
|
for further action, such as obtaining more information about the nature of
|
|
the failure by examining the preserved errno value.
|
|
|
|
Note that the malloc descriptor that we are using is currently located in
|
|
region we are about to unmap, so we first make a local copy of it on the
|
|
stack and use the copy. */
|
|
|
|
PTR
|
|
mmalloc_detach (md)
|
|
void *md;
|
|
{
|
|
struct mdesc mtemp;
|
|
|
|
if (md != NULL)
|
|
{
|
|
|
|
mtemp = *(struct mdesc *) md;
|
|
|
|
/* Now unmap all the pages associated with this region by asking for a
|
|
negative increment equal to the current size of the region. */
|
|
|
|
if ((mtemp.morecore (&mtemp, mtemp.base - mtemp.top)) == NULL)
|
|
{
|
|
/* Update the original malloc descriptor with any changes */
|
|
*(struct mdesc *) md = mtemp;
|
|
}
|
|
else
|
|
{
|
|
if (mtemp.flags & MMALLOC_DEVZERO)
|
|
{
|
|
(void) close (mtemp.fd);
|
|
}
|
|
md = NULL;
|
|
}
|
|
}
|
|
|
|
return (md);
|
|
}
|
|
|
|
|
|
|