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/* syscalls.c --- implement system calls for the M32C simulator.

Copyright (C) 2005, 2007, 2008 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 <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;

    }

}