/* Copyright (C) 2008  Emmanuel Varoquaux

   This file is part of XOS.

   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/>. */

#ifndef USR_H
#define USR_H

#define SC_EXIT        1
#define SC_FORK        2
#define SC_EXEC        3
#define SC_GETPID      4
#define SC_GETPGID     5
#define SC_SETPGID     6
#define SC_CHDIR       7
#define SC_SBRK        8
#define SC_SLEEP       9
#define SC_WAIT       10
#define SC_KILL       11
#define SC_UNAME      12
#define SC_OPEN       13
#define SC_CLOSE      14
#define SC_DUP        15
#define SC_DUP2       16
#define SC_PIPE       17
#define SC_FCNTL      18
#define SC_READ       19
#define SC_WRITE      20
#define SC_SEEK       21
#define SC_STAT       22
#define SC_IOCTL      23
#define SC_CREATE     24
#define SC_REMOVE     25
#define SC_MKDIR      26
#define SC_RMDIR      27
#define SC_RENAME     28
#define SC_MOUNT      29
#define SC_UMOUNT     30
#define SC_REBOOT     31
#define SC_GETTIME    32
#define SC_MMAP       33
#define SC_MUNMAP     34
#define SC_MPROTECT   35

extern int errno;

static inline int _syscall0(unsigned int nr)
{
  register int retval;

  asm volatile ("int $0x80"
                : "=a" (retval)
                : "0" (nr)
                : "memory");
  if (retval < 0) {
    errno = -retval;
    return -1;
  }
  return retval;
}
#define syscall0(nr) _syscall0(nr)

static inline int _syscall1(unsigned int nr, unsigned long a)
{
  register int retval;

  asm volatile ("int $0x80"
                : "=a" (retval)
                : "0" (nr), "b" (a)
                : "memory");
  if (retval < 0) {
    errno = -retval;
    return -1;
  }
  return retval;
}
#define syscall1(nr, a) _syscall1(nr, (unsigned long)a)

static inline int _syscall2(unsigned int nr, unsigned long a, unsigned long b)
{
  register int retval;

  asm volatile ("int $0x80"
                : "=a" (retval)
                : "0" (nr), "b" (a), "c" (b)
                : "memory");
  if (retval < 0) {
    errno = -retval;
    return -1;
  }
  return retval;
}
#define syscall2(nr, a, b) _syscall2(nr, (unsigned long)a, (unsigned long)b)

static inline int _syscall3(unsigned int nr, unsigned long a, unsigned long b, unsigned long c)
{
  register int retval;

  asm volatile ("int $0x80"
                : "=a" (retval)
                : "0" (nr), "b" (a), "c" (b), "d" (c)
                : "memory");
  if (retval < 0) {
    errno = -retval;
    return -1;
  }
  return retval;
}
#define syscall3(nr, a, b, c) _syscall3(nr, (unsigned long)a, (unsigned long)b, (unsigned long)c)

static inline void exit(int status)
{
  syscall1(SC_EXIT, status);
}

static inline int fork()
{
  return syscall0(SC_FORK);
}

static inline int exec(const char *filename, char *const argv[], char *const envp[])
{
  return syscall3(SC_EXEC, filename, argv, envp);
}

static inline int getpgid()
{
  return syscall0(SC_GETPGID);
}

static inline int setpgid(int pid, int pgid)
{
  return syscall2(SC_SETPGID, pid, pgid);
}

static inline int chdir(const char *path)
{
  return syscall1(SC_CHDIR, path);
}

static inline unsigned int sleep(unsigned int seconds)
{
  return syscall1(SC_SLEEP, seconds);
}

static inline int wait(int pid, int *status, int options)
{
  return syscall3(SC_WAIT, pid, status, options);
}

static inline int kill(int pid, int sig)
{
  return syscall2(SC_KILL, pid, sig);
}

static inline int open(const char *filename, int flags)
{
  return syscall2(SC_OPEN, filename, flags);
}

static inline int close(int fd)
{
  return syscall1(SC_CLOSE, fd);
}

static inline int write(int fd, const char *buf, unsigned int count)
{
  return syscall3(SC_WRITE, fd, buf, count);
}

static inline int ioctl(int fd, int request, void *arg)
{
  return syscall3(SC_IOCTL, fd, request, arg);
}

static inline int mount(const char *device, const char *dir, const char *type)
{
  return syscall3(SC_MOUNT, device, dir, type);
}

static inline int umount(const char *dir)
{
  return syscall1(SC_UMOUNT, dir);
}

static inline int reboot(int cmd)
{
  return syscall1(SC_REBOOT, cmd);
}

#define EXIT_FAILURE 1

int printf(const char *format, ...) __attribute__ ((format (printf, 1, 2)));
void perror(const char *s);

#endif