/* syscalls.c --- implement system calls for the M32C simulator.
Copyright (C) 2005-2020 Free Software Foundation, Inc.
Contributed by Red Hat, Inc.
This file is part of the GNU simulators.
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 3 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, see <http://www.gnu.org/licenses/>. */
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#include "gdb/callback.h"
#include "cpu.h"
#include "mem.h"
#include "syscalls.h"
#include "syscall.h"
/* The current syscall callbacks we're using. */
static struct host_callback_struct *callbacks;
void
set_callbacks (struct host_callback_struct *cb)
{
callbacks = cb;
}
/* A16 ABI: arg1 in r1l (QI) or r1 (HI) or stack
arg2 in r2 (HI) or stack
arg3..N on stack
padding: none
A24 ABI: arg1 in r0l (QI) or r0 (HI) or stack
arg2..N on stack
padding: qi->hi
return value in r0l (QI) r0 (HI) r2r0 (SI)
structs: pointer pushed on stack last
*/
int argp, stackp;
static int
arg (int bytes)
{
int rv = 0;
argp++;
if (A16)
{
switch (argp)
{
case 1:
if (bytes == 1)
return get_reg (r1l);
if (bytes == 2)
return get_reg (r1);
break;
case 2:
if (bytes == 2)
return get_reg (r2);
break;
}
}
else
{
switch (argp)
{
case 1:
if (bytes == 1)
return get_reg (r0l);
if (bytes == 2)
return get_reg (r0);
break;
}
}
if (bytes == 0)
bytes = 2;
switch (bytes)
{
case 1:
rv = mem_get_qi (get_reg (sp) + stackp);
if (A24)
stackp++;
break;
case 2:
rv = mem_get_hi (get_reg (sp) + stackp);
break;
case 3:
rv = mem_get_psi (get_reg (sp) + stackp);
if (A24)
stackp++;
break;
case 4:
rv = mem_get_si (get_reg (sp) + stackp);
break;
}
stackp += bytes;
return rv;
}
static void
read_target (char *buffer, int address, int count, int asciiz)
{
char byte;
while (count > 0)
{
byte = mem_get_qi (address++);
*buffer++ = byte;
if (asciiz && (byte == 0))
return;
count--;
}
}
static void
write_target (char *buffer, int address, int count, int asciiz)
{
char byte;
while (count > 0)
{
byte = *buffer++;
mem_put_qi (address++, byte);
if (asciiz && (byte == 0))
return;
count--;
}
}
#define PTRSZ (A16 ? 2 : 3)
static char *callnames[] = {
"SYS_zero",
"SYS_exit",
"SYS_open",
"SYS_close",
"SYS_read",
"SYS_write",
"SYS_lseek",
"SYS_unlink",
"SYS_getpid",
"SYS_kill",
"SYS_fstat",
"SYS_sbrk",
"SYS_argvlen",
"SYS_argv",
"SYS_chdir",
"SYS_stat",
"SYS_chmod",
"SYS_utime",
"SYS_time",
"SYS_gettimeofday",
"SYS_times",
"SYS_link"
};
void
m32c_syscall (int id)
{
static char buf[256];
int rv;
argp = 0;
stackp = A16 ? 3 : 4;
if (trace)
printf ("\033[31m/* SYSCALL(%d) = %s */\033[0m\n", id, callnames[id]);
switch (id)
{
case SYS_exit:
{
int ec = arg (2);
if (verbose)
printf ("[exit %d]\n", ec);
step_result = M32C_MAKE_EXITED (ec);
}
break;
case SYS_open:
{
int path = arg (PTRSZ);
int oflags = arg (2);
int cflags = arg (2);
read_target (buf, path, 256, 1);
if (trace)
printf ("open(\"%s\",0x%x,%#o) = ", buf, oflags, cflags);
if (callbacks)
/* The callback vector ignores CFLAGS. */
rv = callbacks->open (callbacks, buf, oflags);
else
{
int h_oflags = 0;
if (oflags & 0x0001)
h_oflags |= O_WRONLY;
if (oflags & 0x0002)
h_oflags |= O_RDWR;
if (oflags & 0x0200)
h_oflags |= O_CREAT;
if (oflags & 0x0008)
h_oflags |= O_APPEND;
if (oflags & 0x0400)
h_oflags |= O_TRUNC;
rv = open (buf, h_oflags, cflags);
}
if (trace)
printf ("%d\n", rv);
put_reg (r0, rv);
}
break;
case SYS_close:
{
int fd = arg (2);
if (callbacks)
rv = callbacks->close (callbacks, fd);
else if (fd > 2)
rv = close (fd);
else
rv = 0;
if (trace)
printf ("close(%d) = %d\n", fd, rv);
put_reg (r0, rv);
}
break;
case SYS_read:
{
int fd = arg (2);
int addr = arg (PTRSZ);
int count = arg (2);
if (count > sizeof (buf))
count = sizeof (buf);
if (callbacks)
rv = callbacks->read (callbacks, fd, buf, count);
else
rv = read (fd, buf, count);
if (trace)
printf ("read(%d,%d) = %d\n", fd, count, rv);
if (rv > 0)
write_target (buf, addr, rv, 0);
put_reg (r0, rv);
}
break;
case SYS_write:
{
int fd = arg (2);
int addr = arg (PTRSZ);
int count = arg (2);
if (count > sizeof (buf))
count = sizeof (buf);
if (trace)
printf ("write(%d,0x%x,%d)\n", fd, addr, count);
read_target (buf, addr, count, 0);
if (trace)
fflush (stdout);
if (callbacks)
rv = callbacks->write (callbacks, fd, buf, count);
else
rv = write (fd, buf, count);
if (trace)
printf ("write(%d,%d) = %d\n", fd, count, rv);
put_reg (r0, rv);
}
break;
case SYS_getpid:
put_reg (r0, 42);
break;
case SYS_gettimeofday:
{
int tvaddr = arg (PTRSZ);
struct timeval tv;
rv = gettimeofday (&tv, 0);
if (trace)
printf ("gettimeofday: %ld sec %ld usec to 0x%x\n", tv.tv_sec,
tv.tv_usec, tvaddr);
mem_put_si (tvaddr, tv.tv_sec);
mem_put_si (tvaddr + 4, tv.tv_usec);
put_reg (r0, rv);
}
break;
case SYS_kill:
{
int pid = arg (2);
int sig = arg (2);
if (pid == 42)
{
if (verbose)
printf ("[signal %d]\n", sig);
step_result = M32C_MAKE_STOPPED (sig);
}
}
break;
case 11:
{
int heaptop_arg = arg (PTRSZ);
if (trace)
printf ("sbrk: heap top set to %x\n", heaptop_arg);
heaptop = heaptop_arg;
if (heapbottom == 0)
heapbottom = heaptop_arg;
}
break;
}
}