mes/lib/linux/riscv64-mes-gcc/_write.c

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/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2016,2017,2019,2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
* Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
*
* This file is part of GNU Mes.
*
* GNU Mes 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 3 of the License, or (at
* your option) any later version.
*
* GNU Mes 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 GNU Mes. If not, see <http://www.gnu.org/licenses/>.
*/
#include "mes/lib-mini.h"
#define SYS_write 64
// *INDENT-OFF*
ssize_t
_write (int filedes, void const *buffer, size_t size)
{
register long __a7 asm ("a7") = (long) SYS_write;
register long __a0 asm ("a0") = (long) filedes;
register long __a1 asm ("a1") = (long) buffer;
register long __a2 asm ("a2") = (long) size;
asm volatile (
"ecall\n\t"
: "+r" (__a0)
: "r" (__a7), "r" (__a1), "r" (__a2)
);
return (ssize_t)__a0;
}