enabled piping a program from stdin

src/bin/cli/mod.rs

@@ -86,7 +86,11 @@ fn help(command: Option<String>) {
         println!("  rom, -r, --rom <path>: load a rom/binary from path");
         println!("  screen, -s, --screen <type>: use the \"terminal\" or \"window\" display type");
         println!("\nconfiguration:");
-        println!("  george-emu searches for a `george.toml` in the current directory.\n  in `george.toml` you can specify a path for the character rom using the key `char_rom` and the main rom/binary with the key `rom`");
+        println!("  george-emu searches for a `george.toml` in the current directory.\n  in `george.toml` you can specify a path for the character rom\n  using the key `char_rom` and the main rom/binary with the key `rom`");
+        println!("\ndebugging:");
+        println!("  you can pipe in a rom for george to evaluate.");
+        println!("  she'll read it until she reaches a breakpoint (`0x02`) or `stp` instruction,");
+        println!("  then will dump her memory to stdout <3");
         exit(0);
     }
 }

src/bin/main.rs

@@ -1,17 +1,36 @@
+use std::io::{self, stdin, IsTerminal};
+
 #[cfg(not(target_arch = "wasm32"))]
 mod cli;
 
 #[cfg(not(target_arch = "wasm32"))]
 use cli::get_input;
+use georgeemu::memory::{Mem, MemHandle};
 #[cfg(not(target_arch = "wasm32"))]
 use georgeemu::GeorgeEmu;
 #[cfg(not(target_arch = "wasm32"))]
 use minifb::{Scale, ScaleMode, Window, WindowOptions};
 
-#[cfg(not(target_arch = "wasm32"))]
-fn main() {
-    use std::{fs::File, io::Read};
+use std::{fs::File, io::Read};
 
+#[cfg(not(target_arch = "wasm32"))]
+fn main() -> io::Result<()> {
+    use std::io::{stdout, Write};
+
+    use georgeemu::cpu::Cpu;
+
+    let mut input = stdin();
+
+    if !input.is_terminal() {
+        let mut bytes = [0u8; 0x8000];
+        input.read_exact(&mut bytes).unwrap();
+        let memory = make_memory(&bytes);
+        let mut cpu = Cpu::new(memory);
+        let final_output = cpu.run_to_end();
+
+        let _ = stdout().write_all(&final_output);
+        Ok(())
+    } else {
         let window = Window::new(
             "ʕ·ᴥ·ʔ-☆",
             512,
@@ -35,14 +54,22 @@ fn main() {
                 let mut file = File::open(path).unwrap();
                 let mut bin = vec![0; 0x8000];
                 file.read_exact(&mut bin).unwrap();
-            // println!("reading char rom");
                 bin.try_into().unwrap()
             }
-        None => *include_bytes!("../roms/george.rom"),
+            None => *include_bytes!(concat!(env!("CARGO_MANIFEST_DIR"), "/roms/george.rom")),
         };
         let mut emu = GeorgeEmu::builder().rom(rom).window(window).build();
 
         emu.run();
+        Ok(())
+    }
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn make_memory(bytes: &[u8]) -> MemHandle {
+    let mut memory = Mem::new();
+    memory.load_bytes(bytes);
+    MemHandle::new(memory)
 }
 
 #[cfg(target_arch = "wasm32")]

src/cpu.rs

@@ -97,11 +97,18 @@ impl MemoryWriter for Cpu {
 
 impl Cpu {
     pub fn new(memory: MemHandle) -> Self {
+        // reset the cpu on initialization so we don't
+        // scream and cry for two days trying to figure
+        // out why george isn't working <3
+        let low_byte = memory.read(0xFFFC);
+        let high_byte = memory.read(0xFFFD);
+        let pc = (high_byte as u16) << 8 | (low_byte as u16);
+
         Cpu {
             a: 0x00,
             x: 0x00,
             y: 0x00,
-            pc: 0x0000,
+            pc,
             s: 0xFF,
             p: 0b0010_0100,
             irq: false,
@@ -111,8 +118,7 @@ impl Cpu {
             debug: false,
             stopped: false,
             pending_cycles: 0,
-            cycle: false, // cycle_count: 0,
-                          // state_tx,
+            cycle: false,
         }
     }
     pub fn with_receiver(mut self, receiver: CpuReceiver) -> Self {
@@ -265,4 +271,26 @@ impl Cpu {
             self.stop();
         }
     }
+
+    fn quick_cycle(&mut self) {
+        if !self.get_flag(StatusFlag::IrqDisable) && self.irq {
+            self.interrupt();
+        }
+        let opcode = self.read(self.pc);
+        let instruction = get_instruction(opcode);
+        instruction.call(self);
+    }
+
+    pub fn run_to_end(&mut self) -> [u8; 0x10000] {
+        self.quick_cycle();
+        while self.pending_cycles != 0 {
+            let opcode = self.read(self.pc);
+            let instruction = get_instruction(opcode);
+            match instruction.name {
+                "stp" | "breakpoint" => return self.memory.dump(),
+                _ => self.quick_cycle(),
+            }
+        }
+        unreachable!()
+    }
 }

src/instructions.rs

@@ -1028,14 +1028,14 @@ pub const OPCODES: [Instruction; 256] = [
         instr_fn: Some(breakpoint),
         address_fn: None,
         cycles: 0,
-        name: "none",
+        name: "breakpoint",
         addr_mode: "implied",
     },
     Instruction {
         instr_fn: None,
         address_fn: None,
         cycles: 0,
-        name: "none",
+        name: "end",
         addr_mode: "implied",
     },
     Instruction {