linux: Implement mremap in C

Variadic function calls in syscalls.list does not work for all ABIs
(for instance where the argument are passed on the stack instead of
registers) and might have underlying issues depending of the variadic
type (for instance if a 64-bit argument is used).

Checked on x86_64-linux-gnu.
This commit is contained in:
Adhemerval Zanella 2020-06-17 09:29:07 -03:00
parent 83008fa495
commit 5b3e31e312
3 changed files with 42 additions and 1 deletions

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@ -68,6 +68,7 @@ sysdep_routines += adjtimex clone umount umount2 readahead sysctl \
closefrom_fallback \
clone3 clone-internal \
fanotify_mark \
mremap \
CFLAGS-gethostid.c = -fexceptions
CFLAGS-tee.c = -fexceptions -fasynchronous-unwind-tables

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@ -0,0 +1,41 @@
/* Remap a virtual memory address. Linux specific syscall.
Copyright (C) 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 <sys/mman.h>
#include <sysdep.h>
#include <stdarg.h>
#include <stddef.h>
void *
__mremap (void *addr, size_t old_len, size_t new_len, int flags, ...)
{
va_list va;
void *new_addr = NULL;
if (flags & MREMAP_FIXED)
{
va_start (va, flags);
new_addr = va_arg (va, void *);
va_end (va);
}
return (void *) INLINE_SYSCALL_CALL (mremap, addr, old_len, new_len, flags,
new_addr);
}
libc_hidden_def (__mremap)
weak_alias (__mremap, mremap)

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@ -35,7 +35,6 @@ mincore - mincore i:aUV mincore
mlock - mlock i:bU mlock
mlockall - mlockall i:i mlockall
mount EXTRA mount i:sssUp __mount mount
mremap EXTRA mremap b:aUUip __mremap mremap
munlock - munlock i:aU munlock
munlockall - munlockall i: munlockall
nfsservctl EXTRA nfsservctl i:ipp __compat_nfsservctl nfsservctl@GLIBC_2.0:GLIBC_2.28