glibc/sysdeps/unix/sysv/linux/mmap64.c
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

69 lines
2.3 KiB
C

/* mmap - map files or devices into memory. Linux version.
Copyright (C) 1999-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sysdep.h>
#include <mmap_internal.h>
#ifdef __NR_mmap2
/* To avoid silent truncation of offset when using mmap2, do not accept
offset larger than 1 << (page_shift + off_t bits). For archictures with
32 bits off_t and page size of 4096 it would be 1^44. */
# define MMAP_OFF_HIGH_MASK \
((-(MMAP2_PAGE_UNIT << 1) << (8 * sizeof (off_t) - 1)))
#else
/* Some ABIs might use __NR_mmap while having sizeof (off_t) smaller than
sizeof (off64_t) (currently only MIPS64n32). For this case just set
zero the higher bits so mmap with large offset does not fail. */
# define MMAP_OFF_HIGH_MASK 0x0
#endif
#define MMAP_OFF_MASK (MMAP_OFF_HIGH_MASK | MMAP_OFF_LOW_MASK)
/* An architecture may override this. */
#ifndef MMAP_PREPARE
# define MMAP_PREPARE(addr, len, prot, flags, fd, offset)
#endif
void *
__mmap64 (void *addr, size_t len, int prot, int flags, int fd, off64_t offset)
{
MMAP_CHECK_PAGE_UNIT ();
if (offset & MMAP_OFF_MASK)
return (void *) INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
MMAP_PREPARE (addr, len, prot, flags, fd, offset);
#ifdef __NR_mmap2
return (void *) MMAP_CALL (mmap2, addr, len, prot, flags, fd,
(off_t) (offset / MMAP2_PAGE_UNIT));
#else
return (void *) MMAP_CALL (mmap, addr, len, prot, flags, fd, offset);
#endif
}
weak_alias (__mmap64, mmap64)
libc_hidden_def (__mmap64)
#ifdef __OFF_T_MATCHES_OFF64_T
weak_alias (__mmap64, mmap)
weak_alias (__mmap64, __mmap)
libc_hidden_def (__mmap)
#endif