feat(vm): Single-step mode

1 files changed, 31 insertions, 0 deletions

diff --git a/vm/src/vmm/command.rs b/vm/src/vmm/command.rs
index 628a30f..6791663 100644
--- a/vm/src/vmm/command.rs
+++ b/vm/src/vmm/command.rs
@@ -71,6 +71,7 @@ pub(super) fn parse_and_exec(input: String, vm: &mut VirtualMachine) -> Result<(
     }
 
     match args[0] {
+        /* Run mode */
         "r" | "run" => {
             expects_n_args(&args, 1)?;
             if ! vm.is_halted() {
@@ -78,6 +79,36 @@ pub(super) fn parse_and_exec(input: String, vm: &mut VirtualMachine) -> Result<(
             }
             vm.set_start(args[1].parse().unwrap());
         },
+
+        /* Single step mode */
+        "s" | "single" => {
+            expects_n_args(&args, 1)?;
+            if ! vm.is_halted() {
+                return Err(format!("Machine already running!"));
+            }
+            if vm.is_single_step() {
+                return Err(format!("Machine already in single-step mode!"));
+            }
+            vm.set_single_step(true);
+            vm.set_start(args[1].parse().unwrap());
+        },
+        "c" | "continue" => {
+            expects_n_args(&args, 0)?;
+            if ! vm.is_single_step() {
+                return Err(format!("Machine not in single-step mode!"));
+            }
+            vm.set_single_step(false);
+            vm.set_halt(false);
+        },
+        "n" | "next" => {
+            expects_n_args(&args, 0)?;
+            if ! vm.is_single_step() {
+                return Err(format!("Machine not in single-step mode!"));
+            }
+            vm.step();
+        },
+
+        /* Other */
         "q" | "quit" | "e" | "exit" => return Err(String::new()),
         _ => {
             for arg in args {