Linux: Introduce __brk_call for invoking the brk system call

Alpha and sparc can now use the generic implementation.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit b57ab258c1)
This commit is contained in:
Florian Weimer 2022-05-16 18:41:43 +02:00
parent e7ca2a475c
commit 43d77ef9b8
4 changed files with 71 additions and 20 deletions

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@ -0,0 +1,28 @@
/* Invoke the brk system call. Alpha version.
Copyright (C) 2022 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/>. */
static inline void *
__brk_call (void *addr)
{
unsigned long int result = INTERNAL_SYSCALL_CALL (brk, addr);
if (result == -ENOMEM)
/* Mimic the default error reporting behavior. */
return addr;
else
return (void *) result;
}

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@ -19,6 +19,7 @@
#include <errno.h>
#include <unistd.h>
#include <sysdep.h>
#include <brk_call.h>
/* This must be initialized data because commons can't have aliases. */
void *__curbrk = 0;
@ -33,7 +34,7 @@ weak_alias (__curbrk, ___brk_addr)
int
__brk (void *addr)
{
__curbrk = (void *) INTERNAL_SYSCALL_CALL (brk, addr);
__curbrk = __brk_call (addr);
if (__curbrk < addr)
{
__set_errno (ENOMEM);

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@ -0,0 +1,25 @@
/* Invoke the brk system call. Generic Linux version.
Copyright (C) 2022 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/>. */
static inline void *
__brk_call (void *addr)
{
/* The default implementation reports errors through an unchanged
break. */
return (void *) INTERNAL_SYSCALL_CALL (brk, addr);
}

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@ -1,5 +1,5 @@
/* Change data segment size. Linux/Alpha.
Copyright (C) 2020-2021 Free Software Foundation, Inc.
/* Invoke the brk system call. Sparc version.
Copyright (C) 2022 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
@ -16,23 +16,20 @@
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <unistd.h>
#include <sysdep.h>
#ifdef __arch64__
# define SYSCALL_NUM "0x6d"
#else
# define SYSCALL_NUM "0x10"
#endif
void *__curbrk = 0;
int
__brk (void *addr)
static inline void *
__brk_call (void *addr)
{
/* Alpha brk returns -ENOMEM in case of failure. */
__curbrk = (void *) INTERNAL_SYSCALL_CALL (brk, addr);
if ((unsigned long) __curbrk == -ENOMEM)
{
__set_errno (ENOMEM);
return -1;
}
return 0;
register long int g1 asm ("g1") = __NR_brk;
register long int o0 asm ("o0") = (long int) addr;
asm volatile ("ta " SYSCALL_NUM
: "=r"(o0)
: "r"(g1), "0"(o0)
: "cc");
return (void *) o0;
}
weak_alias (__brk, brk)