#include SYSCALLNOS
/* Description of (most) MIPS system calls so SPIM can pass the correct
   arguments to the system when a user program executes a syscall in
   binary mode. */
typedef struct {
    int syscall_num;
    int syscall_type;
    int args[5];
    char *syscall_name;
} syscall_desc;

enum {BAD_SYSCALL, UNIX_SYSCALL, SPC_SYSCALL};
enum {NO_ARG, INT_ARG, ADDR_ARG, STR_ARG, FD_ARG};  /* Type of argument */

syscall_desc syscall_table[] =
{
#include SYSCALLHEADER
};
#define MAX_SYSCALL	asize(syscall_table)

#define SYSCALL_ARG(REGOFF, ARG, REG)        			             \
( (syscall_table[R[REGOFF]].args[ARG] == ADDR_ARG) ? mem_address_nullok(R[REG],C_WRITE) : \
  (syscall_table[R[REGOFF]].args[ARG] == STR_ARG)  ? mem_address_nullok(R[REG],C_WRITE)  : \
 ((syscall_table[R[REGOFF]].args[ARG] == FD_ARG) && (R[REG] < MAXFDS)) ? prog_fds[R[REG]] : R[REG])