Add flag to just run the CPU

Cargo.lock

@@ -108,13 +108,28 @@ checksum = "71655c45cb9845d3270c9d6df84ebe72b4dad3c2ba3f7023ad47c144e4e473a5"
 dependencies = [
  "atty",
  "bitflags",
+ "clap_derive",
  "clap_lex",
  "indexmap",
+ "once_cell",
  "strsim",
  "termcolor",
  "textwrap",
 ]
 
+[[package]]
+name = "clap_derive"
+version = "3.2.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ea0c8bce528c4be4da13ea6fead8965e95b6073585a2f05204bd8f4119f82a65"
+dependencies = [
+ "heck",
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "clap_lex"
 version = "0.2.4"
@@ -438,6 +453,7 @@ dependencies = [
  "anyhow",
  "bitflags",
  "bitvec",
+ "clap",
  "derive-try-from-primitive",
  "elf",
  "human-repr",
@@ -555,6 +571,30 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "proc-macro-error"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da25490ff9892aab3fcf7c36f08cfb902dd3e71ca0f9f9517bea02a73a5ce38c"
+dependencies = [
+ "proc-macro-error-attr",
+ "proc-macro2",
+ "quote",
+ "syn",
+ "version_check",
+]
+
+[[package]]
+name = "proc-macro-error-attr"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a1be40180e52ecc98ad80b184934baf3d0d29f979574e439af5a55274b35f869"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "version_check",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.47"
@@ -856,6 +896,12 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "936e4b492acfd135421d8dca4b1aa80a7bfc26e702ef3af710e0752684df5372"
 
+[[package]]
+name = "version_check"
+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
+
 [[package]]
 name = "vte"
 version = "0.10.1"

Cargo.toml

@@ -9,6 +9,7 @@ edition = "2021"
 anyhow = "1.0.66"
 bitflags = "1.3.2"
 bitvec = "1.0.0"
+clap = { version = "3.2.23", features = ["clap_derive", "derive"] }
 derive-try-from-primitive = "1.0.0"
 elf = "0.7.0"
 human-repr = { version = "1.0.1", features = ["iec", "space"] }

src/main.rs

@@ -20,6 +20,7 @@ use crate::{
     m68k::{BusError, M68K},
 };
 use anyhow::anyhow;
+use clap::Parser;
 use disas::DisassemblyError;
 use indexmap::IndexSet;
 use itertools::Itertools;
@@ -46,7 +47,18 @@ struct EmuState {
     address_breakpoints: IndexSet<u32>,
 }
 
+/// 68K Backplane Computer Emulator
+#[derive(Parser, Debug)]
+#[clap(name = "68KEmu", author, version, about, long_about = None)]
+struct Args {
+    /// Just run the CPU instad of starting a REPL
+    #[clap(short, long)]
+    run: bool,
+}
+
 fn main() -> Result<(), anyhow::Error> {
+    let args = Args::parse();
+
     let config_str = fs::read_to_string("config.toml")
         .map_err(|e| anyhow!("Could not read config file ({})", e))?;
     let config: EmuConfig =
@@ -58,11 +70,24 @@ fn main() -> Result<(), anyhow::Error> {
             symbol_tables.load_table(path, true)?;
         }
     }
-    Repl::<_, anyhow::Error>::new(EmuState {
+    let mut state = EmuState {
         cpu: M68K::new(backplane),
         symbol_tables,
         address_breakpoints: IndexSet::new(),
-    })
+    };
+    if args.run {
+        let mut out = String::new();
+        while !state.cpu.stopped {
+            state.cpu.step();
+        }
+        out += &format!("{}\n", state.cpu);
+        let pc = state.cpu.pc();
+        out += &disas_fmt(&mut state.cpu, pc, &state.symbol_tables).0;
+        out.pop(); // Remove trailing newline
+        println!("{}", out);
+        return Ok(());
+    }
+    Repl::<_, anyhow::Error>::new(state)
     .with_name("68KEmu")
     .with_version("0.1.0")
     .with_banner("68K Backplane Computer Emulator")