burritos/src/kernel/exception.rs

289 lines
9.3 KiB
Rust

use std::rc::Rc;
use crate::simulator::{machine::{ExceptionType, Machine}, error::{MachineOk, MachineError}};
use super::system::System;
/// The halt system call. Stops Burritos.
pub const SC_SHUTDOWN: u8 = 0;
/// The exit system call
///
/// Ends the calling thread
pub const SC_EXIT: u8 = 1;
/// The exec system call
///
/// Creates a new process (thread+address space)
pub const SC_EXEC: u8 = 2;
/// The join system call
///
/// Wait for the thread idThread to finish
pub const SC_JOIN: u8 = 3;
/// The create system call
///
/// Create a new file in nachos file system
pub const SC_CREATE: u8 = 4;
/// The open system call
///
/// Opens a file and returns an openfile identifier
pub const SC_OPEN: u8 = 5;
/// The read system call
///
/// Read in a file or the console
pub const SC_READ: u8 = 6;
/// The write system call
///
/// Write in a file or at the console
pub const SC_WRITE: u8 = 7;
/// Seek to a given position in an opened file
pub const SC_SEEK: u8 = 8;
/// The close system call
///
/// Close a file
pub const SC_CLOSE: u8 = 9;
/// The newThread system call
///
/// Create a new thread in the same address space
pub const SC_NEW_THREAD: u8 = 10;
/// The Yield System call
///
/// Relinquish the CPU if any other thread is runnable
pub const SC_YIELD: u8 = 11;
/// the PError system call
///
/// print the last error message
pub const SC_PERROR: u8 = 12;
/// carry out P() on the semaphore
pub const SC_P: u8 = 13;
/// carry out V() on the semaphore
pub const SC_V: u8 = 14;
/// create a semaphore and add it in g_objects_addrs
pub const SC_SEM_CREATE: u8 = 15;
/// destroy the semaphore corresponding to the id
pub const SC_SEM_DESTROY: u8 = 16;
/// create a lock and add it to g_object_addrs
pub const SC_LOCK_CREATE: u8 = 17;
/// destroy the lock corresponding to the id
pub const SC_LOCK_DESTROY: u8 = 18;
/// carry out acquire() on the lock
pub const SC_LOCK_ACQUIRE: u8 = 19;
/// carry out release() on the lock
pub const SC_LOCK_RELEASE: u8 = 20;
/// create a condition variable and add it to g_object_addrs
pub const SC_COND_CREATE: u8 = 21;
/// destroy the condition variable corresponding to the id
pub const SC_COND_DESTROY: u8 = 22;
/// carry out wait() on the condition
pub const SC_COND_WAIT: u8 = 23;
/// carry out signal() on the condition
pub const SC_COND_SIGNAL: u8 = 24;
/// carry out broadcast() on the condition
pub const SC_COND_BROADCAST: u8 = 25;
/// the TtySend system call
///
/// Sends some char by the serial line emulated
pub const SC_TTY_SEND: u8 = 26;
/// the TtyReceive system call
///
/// read some char on the serial line
pub const SC_TTY_RECEIVE: u8 = 27;
/// the Mkdir system call
///
/// make a new directory in the file system
pub const SC_MKDIR: u8 = 28;
/// the Rmdir system call
///
/// remove a directory from the file system
pub const SC_RMDIR: u8 = 29;
/// The Remove system call
///
/// Remove a file from the file system
pub const SC_REMOVE: u8 = 30;
/// The FSList system call
///
/// Lists all the file and directories in the filesystem
pub const SC_FSLIST: u8 = 31;
// The systime system call. Gets the system time
pub const SC_SYS_TIME: u8 = 32;
/// Map a file in memory
pub const SC_MMAP: u8 = 33;
/// Behaviour undefined and currently unused
pub const SC_DEBUG: u8 = 34;
pub const CONSOLE_OUTPUT: u8 = 1;
// todo : returns new types, not just machine errors and machine ok
pub fn call(exception: &ExceptionType, machine: &mut Machine, system: &mut System) -> Result<MachineOk, MachineError> {
match exception {
ExceptionType::NoException => Err("No Exception no yet implemented")?,
ExceptionType::SyscallException => syscall(machine, system),
ExceptionType::PagefaultException => Err("Page Fault Exception not yet implemented")?,
ExceptionType::ReadOnlyException => Err("Read Only Exception not yet implemented")?,
ExceptionType::BusErrorException => Err("Bus Error Exception not yet implemented")?,
ExceptionType::AddressErrorException => Err("AddressErrorException not yet implemented")?,
ExceptionType::OverflowException => Err("OverflowException not yet implemented")?,
ExceptionType::IllegalInstrException => Err("IllegalInstrException not yet implemented")?,
ExceptionType::NumExceptionTypes => Err("NumExceptionTypes not yet implemented")?,
}
}
fn syscall(machine: &mut Machine, system: &mut System) -> Result<MachineOk, MachineError> {
let call_type = machine.read_int_register(17) as u8;
match call_type {
SC_SHUTDOWN => Ok(MachineOk::Shutdown),
SC_EXIT => {
let th = match &system.get_thread_manager().g_current_thread {
Some(th) => th.clone(),
None => Err("Current thread is None")?
};
system.get_thread_manager().thread_finish(machine, th);
Ok(MachineOk::Ok)
},
SC_EXEC => todo!(),
SC_JOIN => todo!(),
SC_CREATE => todo!(),
SC_OPEN => todo!(),
SC_READ => todo!(),
SC_WRITE => {
let address = machine.read_int_register(10);
let size = machine.read_int_register(11);
// openfileid or 1 (console)
let f = machine.read_int_register(12);
// load buffer
let mut buffer = "".to_string();
for i in 0..size {
buffer.push((machine.read_memory(1, (address + i) as usize)) as u8 as char);
}
if f as u8 == CONSOLE_OUTPUT {
println!("{}", buffer); // todo replace with console driver in the future
Ok(MachineOk::Ok)
} else {
Err("SC_WRITE to file is not yet implemented")?
}
},
SC_SEEK => todo!(),
SC_CLOSE => todo!(),
SC_NEW_THREAD => todo!(),
SC_YIELD => todo!(),
SC_PERROR => todo!(),
SC_P => todo!(),
SC_V => todo!(),
SC_SEM_CREATE => {
let addr_name = machine.read_int_register(10);
let initial_count = machine.read_int_register((11));
let size = get_length_param(addr_name as usize, machine);
let name = get_string_param(addr_name, size, machine);
if initial_count <0{
}
Ok(MachineOk::Ok)
},
SC_SEM_DESTROY => todo!(),
SC_LOCK_CREATE => todo!(),
SC_LOCK_DESTROY => todo!(),
SC_LOCK_ACQUIRE => todo!(),
SC_LOCK_RELEASE => todo!(),
SC_COND_CREATE => todo!(),
SC_COND_DESTROY => todo!(),
SC_COND_WAIT => todo!(),
SC_COND_SIGNAL => todo!(),
SC_COND_BROADCAST => todo!(),
SC_TTY_SEND => todo!(),
SC_TTY_RECEIVE => todo!(),
SC_MKDIR => todo!(),
SC_RMDIR => todo!(),
SC_REMOVE => todo!(),
SC_FSLIST => todo!(),
SC_SYS_TIME => todo!(),
SC_MMAP => todo!(),
SC_DEBUG => todo!(),
_ => todo!()
}
}
fn get_length_param(addr: usize, machine: & Machine) -> usize{
let mut i = 0;
let mut c = 1;
while c!= 0 {
c = machine.read_memory(1, addr + i);
i+=1;
}
i + 1
}
fn get_string_param(addr: i64, maxlen: usize, machine: &Machine) -> Vec<char>{
let mut dest = Vec::with_capacity(maxlen);
let mut i: usize = 0;
let mut c = 1;
while c != 0 && i < maxlen {
c = machine.read_memory(1, addr as usize + i) as u8;
//dest.push(c as char);
dest[i] = c as char;
i += 1;
}
dest[maxlen - 1] = '\0';
dest
}
#[cfg(test)]
mod test {
use crate::kernel::exception::{SC_SHUTDOWN, SC_WRITE};
use crate::kernel::system::System;
use crate::simulator::instruction::Instruction;
use crate::simulator::machine::Machine;
#[test]
fn test_sc_shutdown() {
let mut machine = Machine::init_machine();
machine.write_int_register(17, SC_SHUTDOWN as i64); // Set type to shutdown
let ecall = Instruction::new(0b000000000000_00000_000_00000_1110011);
machine.write_memory(4, 0, 0b000000000000_00000_000_00000_1110011); // ecall
machine.write_memory(4, 4, 0b000000001010_00000_000_00001_0010011); // r1 <- 10
let mut system = System::default();
machine.run(&mut system);
// If the machine was stopped with no error, the shutdown worked
assert_ne!(machine.read_int_register(1), 10); // Check if the next instruction was executed
}
// This test print HELLO in the console
#[test]
#[ignore]
fn test_sc_print() {
let mut machine = Machine::init_machine();
let address = machine.read_int_register(10);
// Write string 'HELLO' in memory
machine.write_memory(1, 4000, 72);
machine.write_memory(1, 4001, 69);
machine.write_memory(1, 4002, 76);
machine.write_memory(1, 4003, 76);
machine.write_memory(1, 4004, 79);
machine.write_int_register(10, 4000); // String address
machine.write_int_register(11, 5); // String size
machine.write_int_register(12, 1); // Console output
machine.write_memory(4, 0, 0b000000000000_00000_000_00000_1110011); // ecall
machine.write_int_register(17, SC_WRITE as i64); // Set type to write
machine.write_memory(4, 4, 0b000000000000_00000_000_10001_0010011); // r17 <- SC_SHUTDOWN
machine.write_memory(4, 8, 0b000000000000_00000_000_00000_1110011); // ecall
let mut system = System::default();
machine.run(&mut system);
}
}