From 5000c28b970bfa8bde974146d4aac5a48e2f4647 Mon Sep 17 00:00:00 2001
From: Quentin Legot <legotquentin@gmail.com>
Date: Sun, 7 May 2023 14:50:41 +0200
Subject: [PATCH] Fix endianness issues particulary with strings

---
 src/kernel/exception.rs  | 8 ++++++--
 src/simulator/loader.rs  | 7 ++++++-
 src/simulator/machine.rs | 2 +-
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/kernel/exception.rs b/src/kernel/exception.rs
index 45fb0c1..c982264 100644
--- a/src/kernel/exception.rs
+++ b/src/kernel/exception.rs
@@ -154,13 +154,17 @@ fn syscall(machine: &mut Machine, system: &mut System) -> Result<MachineOk, Mach
             let f = machine.read_int_register(12);
 
             // load buffer
-            let mut buffer = "".to_string();
+            let mut buffer = String::new();
+            let mut val: [u8; 4] = [0; 4];
+            for (j, elem) in val.iter_mut().enumerate() {
+                *elem = machine.read_memory(1, address as usize + j) as u8;
+            }
             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
+                print!("{}", buffer); // todo replace with console driver in the future
                 Ok(MachineOk::Ok)
             } else {
                 Err("SC_WRITE to file is not yet implemented")?
diff --git a/src/simulator/loader.rs b/src/simulator/loader.rs
index 18f56fe..db3e610 100644
--- a/src/simulator/loader.rs
+++ b/src/simulator/loader.rs
@@ -463,7 +463,12 @@ impl Loader {
                             buf[k] = self.bytes.get(section.image_offset as usize + j + k).copied().ok_or(LoaderError::ParsingError(format!("index 0x{:x} is out of bound because list have a size of 0x{:x} (image offset 0x{:x}, j 0x{:x}, k 0x{:x})", section.image_offset as usize + j + k, self.bytes.len(), section.image_offset, j, k)))?;
                         }
                     }
-                    machine.write_memory(4, start_index + section.virt_addr as usize + j, u32::from_le_bytes(buf) as u64);
+
+                    machine.write_memory(1, start_index + section.virt_addr as usize + j, buf[0] as u64);
+                    machine.write_memory(1, start_index + section.virt_addr as usize + j + 1, buf[1] as u64);
+                    machine.write_memory(1, start_index + section.virt_addr as usize + j + 2, buf[2] as u64);
+                    machine.write_memory(1, start_index + section.virt_addr as usize + j + 3, buf[3] as u64);
+                    
                 }
             }
         }
diff --git a/src/simulator/machine.rs b/src/simulator/machine.rs
index fae3a68..5c87dea 100644
--- a/src/simulator/machine.rs
+++ b/src/simulator/machine.rs
@@ -284,7 +284,7 @@ impl Machine {
 			*elem = self.main_memory[self.pc as usize + i];
 		}
 		
-		let val = u32::from_be_bytes(val) as u64;
+		let val = u32::from_le_bytes(val) as u64;
 		let inst : Instruction = Instruction::new(val);
 		if self.debug {
 			self.print_status();