Format + some clipy

src/chip.rs

@@ -1,47 +1,34 @@
 use cpu::CPU;
-use devices;
+use devices::{oscillator::Oscillator, ram::Ram, usart::Usart, Device, DeviceTree};
 
 use slog;
 
-
 pub struct Chip {
     log: slog::Logger,
     pub cpu: CPU,
     pub rom: Box<[u8]>,
-    pub device_tree: devices::DeviceTree,
-
+    pub device_tree: DeviceTree,
     // TODO: List of devices
 }
 
 impl Chip {
     pub fn new(log: slog::Logger, rom: Box<[u8]>) -> Chip {
         // Internal registers
-        let internal_regs = devices::ram::RAM::new(log.clone());
-        let ram_device = devices::ram::RAM::new(log.clone());
-        let usart_device = devices::usart::USART::new(log.clone());
-        let mut dev_tree = devices::DeviceTree::new(log.clone());
+        let internal_regs = Ram::new(log.clone());
+        let ram_device = Ram::new(log.clone());
+        let usart_device = Usart::new(log.clone());
+        let mut dev_tree = DeviceTree::new(log.clone());
 
         // Add RAM and USART
-        dev_tree.add_device(
-            devices::Device::new(Box::new(ram_device), 0x2000, 0x2000)
-        );
-        dev_tree.add_device(
-            devices::Device::new(Box::new(internal_regs), 0, 0x40)
-        );
-        dev_tree.add_device(
-            devices::Device::new(Box::new(usart_device), 0x8A0, 0x8A7 - 0x8A0 + 1)
-        );
-        dev_tree.add_device(
-            devices::Device::new(
-                Box::new(devices::oscillator::Oscillator::new(log.clone())),
-                0x50, 0x07
-            )
-        );
+        dev_tree.add_device(Device::new(ram_device, 0x2000, 0x2000));
+        dev_tree.add_device(Device::new(internal_regs, 0, 0x40));
+        dev_tree.add_device(Device::new(usart_device, 0x8A0, 0x8A7 - 0x8A0 + 1));
+        dev_tree.add_device(Device::new(Oscillator::new(log.clone()), 0x50, 0x07));
 
         Self {
             log: log.clone(),
             cpu: CPU::new(log),
-            rom: rom,
+            rom,
             device_tree: dev_tree,
         }
     }

src/cpu.rs

@@ -1,12 +1,10 @@
 #![allow(dead_code)]
 #![allow(unused_variables)]
 
-use decoder;
-use decoder::{IncrementMode, Instruction};
-use regs::{GeneralPurposeRegister, GeneralPurposeRegisterPair, StatusFlag};
-use chip_definitions;
-
+use chip_definitions::IOAdress;
+use decoder::{self, IncrementMode, Instruction};
 use devices::DeviceTree;
+use regs::{GeneralPurposeRegister, GeneralPurposeRegisterPair, StatusFlag};
 
 use std::fmt;
 
@@ -54,14 +52,14 @@ impl fmt::Display for CPU {
                 write!(f, "-")?;
             }
         }
-        write!(f, "\n")?;
+        writeln!(f)?;
         for i in 0..32 {
             write!(f, " R{:-2}={:02X} ", i, self.registers[i])?;
             if (i + 1) % 10 == 0 {
-                write!(f, "\n")?;
+                writeln!(f)?;
             }
         }
-        write!(f, "\n")
+        writeln!(f)
     }
 }
 
@@ -71,19 +69,19 @@ impl CPU {
             registers: [0u8; 32],
             pc: 0,   // Reset vector
             sreg: 0, // Uninitialized as well
-            logger: logger,
+            logger,
         }
     }
 
     pub fn get_sp(&self, mem: &mut DeviceTree) -> u16 {
-        let spl: u16 = mem.read(chip_definitions::IOAdress::SPL as u32) as u16;
-        let sph: u16 = mem.read(chip_definitions::IOAdress::SPH as u32) as u16;
+        let spl: u16 = mem.read(IOAdress::SPL as u32) as u16;
+        let sph: u16 = mem.read(IOAdress::SPH as u32) as u16;
         sph << 8 | spl
     }
 
     fn set_sp(&self, mem: &mut DeviceTree, val: u16) {
-        mem.write(chip_definitions::IOAdress::SPL as u32, val as u8);
-        mem.write(chip_definitions::IOAdress::SPH as u32, (val >> 8) as u8);
+        mem.write(IOAdress::SPL as u32, val as u8);
+        mem.write(IOAdress::SPH as u32, (val >> 8) as u8);
     }
 
     fn test_flag(&self, flag: StatusFlag) -> bool {
@@ -232,7 +230,11 @@ impl CPU {
     }
 
     // Returns # of ticks the executed instruction took
-    pub fn step(&mut self, rom: &mut [u8], device_tree: &mut DeviceTree) -> Result<usize, CPUError> {
+    pub fn step(
+        &mut self,
+        rom: &mut [u8],
+        device_tree: &mut DeviceTree,
+    ) -> Result<usize, CPUError> {
         // Instruction fetch
         if (self.pc as usize) * 2 >= rom.len() {
             return Err(CPUError::OutOfBoundsException);
@@ -316,16 +318,16 @@ impl CPU {
                     IncrementMode::ConstantOffset(o) => base.wrapping_add(u16::from(o)),
                 };
                 self.ram_write(device_tree, addr, self.get_register(src_reg))?;
-            },
+            }
             Instruction::LD(ref dst_reg, ref ptr, ref inc_mode) => {
                 let base = self.get_register_pair(ptr);
                 /*
                 // TODO: RAMPX/Y/Z
-                if ptr.low() == 26 && ram[chip_definitions::IOAdress::RAMPX as usize] > 0 {
+                if ptr.low() == 26 && ram[IOAdress::RAMPX as usize] > 0 {
                     panic!("Unexpected");
-                } else if ptr.low() == 28 && ram[chip_definitions::IOAdress::RAMPY as usize] > 0 {
+                } else if ptr.low() == 28 && ram[IOAdress::RAMPY as usize] > 0 {
                     panic!("Unexpected");
-                } else if ptr.low() == 30 && ram[chip_definitions::IOAdress::RAMPZ as usize] > 0 {
+                } else if ptr.low() == 30 && ram[IOAdress::RAMPZ as usize] > 0 {
                     panic!("Unexpected");
                 }
                 */
@@ -347,17 +349,16 @@ impl CPU {
             Instruction::ELPM(ref dst_reg, ref inc_mode) => {
                 let Zb = self.get_register_pair(&30u8.into());
                 // TODO: Only use required bits, other read as zero (according to datasheet)
-                let Z =
-                    Zb as usize |
-                    (device_tree.read(chip_definitions::IOAdress::RAMPZ as u32) as usize) << 16;
+                let Z = Zb as usize | (device_tree.read(IOAdress::RAMPZ as u32) as usize) << 16;
 
                 match *inc_mode {
                     IncrementMode::PostIncrement => {
                         self.set_register_pair(&30u8.into(), Zb.wrapping_add(1));
-                        device_tree.write(chip_definitions::IOAdress::RAMPZ as u32, (Z.wrapping_add(1) >> 16) as u8);
-                    },
+                        device_tree.write(IOAdress::RAMPZ as u32, (Z.wrapping_add(1) >> 16) as u8);
+                    }
                     _ => {
                         // This instruction does only support None + PostIncrement
+                        panic!("Invalid increment mode for ELPM: {:?}", inc_mode);
                     }
                 }
                 if Z >= rom.len() {
@@ -384,13 +385,14 @@ impl CPU {
                     }
                     _ => {
                         // This instruction does only support None + PostIncrement
+                        panic!("Invalid increment mode for LPM: {:?}", inc_mode);
                     }
                 }
             }
             Instruction::OUT(ref addr, ref val) => {
                 let val = self.get_register(val);
                 self.ram_write(device_tree, *addr, val)?;
-            },
+            }
             Instruction::IN(ref reg, ref addr) => {
                 let v = self.ram_read(device_tree, *addr)?;
                 self.set_register(reg, v);
@@ -408,7 +410,7 @@ impl CPU {
                 self.push(device_tree, ((ret_to >> 8) & 0xFF) as u8)?;
                 self.push(device_tree, (ret_to & 0xFF) as u8)?;
                 self.pc = (self.pc as i32 + *addr as i32) as u32;
-            },
+            }
             Instruction::RET => {
                 let mut ret_to = self.pop(device_tree)? as u32;
                 ret_to += (self.pop(device_tree)? as u32) << 8;
@@ -422,7 +424,7 @@ impl CPU {
             Instruction::PUSH(ref reg) => {
                 let v = self.registers[reg.as_usize()];
                 self.push(device_tree, v)?;
-            },
+            }
             Instruction::SUBI(ref d, ref v) => {
                 let dv = self.get_register(d);
                 let vres = dv.wrapping_sub(*v);
@@ -545,16 +547,20 @@ impl CPU {
                 self.update_flags_zns_8(res);
             }
             Instruction::STS16(ref addr, ref r) => {
-                let rampd = device_tree.read(chip_definitions::IOAdress::RAMPD as u32);
-                if rampd != 0 { panic!("This is unexpected (for now)"); }
+                let rampd = device_tree.read(IOAdress::RAMPD as u32);
+                if rampd != 0 {
+                    panic!("This is unexpected (for now)");
+                }
                 self.ram_write(device_tree, *addr, self.get_register(r))?;
-            },
+            }
             Instruction::STS8(ref addr, ref r) => {
                 self.ram_write(device_tree, *addr as u16, self.get_register(r))?;
-            },
+            }
             Instruction::LDS16(ref r, ref addr) => {
-                let rampd = device_tree.read(chip_definitions::IOAdress::RAMPD as u32);
-                if rampd != 0 { panic!("This is unexpected (for now)"); }
+                let rampd = device_tree.read(IOAdress::RAMPD as u32);
+                if rampd != 0 {
+                    panic!("This is unexpected (for now)");
+                }
                 let v = self.ram_read(device_tree, *addr)?;
                 self.set_register(r, v);
             }
@@ -655,7 +661,7 @@ impl CPU {
                 if self.test_flag(StatusFlag::BitCopyStorage) {
                     rv |= 1 << *v;
                 }
-                let r = self.set_register(r, rv);
+                self.set_register(r, rv);
             }
             Instruction::SWAP(ref r) => {
                 let rv = self.get_register(r);

src/decoder.rs

@@ -282,7 +282,7 @@ pub fn decode(data: &[u8]) -> Result<Instruction, DecodingError> {
     if v & 0b1111_1111_0000_0000 == 0b0000_0011_0000_0000 {
         // FMUL/FMULS/FMULSU/MULSU
         let d = ((v & 0b0111_0000) >> 4) as u8;
-        let r = ((v & 0b0111)) as u8;
+        let r = (v & 0b0111) as u8;
         let mode = v & 0b1000_1000;
         match mode {
             0b0000_0000 => return Ok(Instruction::MULSU((d + 16).into(), (r + 16).into())),
@@ -308,7 +308,7 @@ pub fn decode(data: &[u8]) -> Result<Instruction, DecodingError> {
         let K = (((v & 0b1100_0000) >> 2) | (v & 0b1111)) as u8;
         let d = ((v & 0b1111_0000) >> 4) as u8;
         let r = (v & 0b1111) as u8;
-        let A = u16::from((v & 0b1111_1000) >> 3);
+        let A = (v & 0b1111_1000) >> 3;
         let b = (v & 0b0111) as u8;
         match v & 0b1111_1111_0000_0000 {
             0b1001_0110_0000_0000 => {
@@ -318,16 +318,20 @@ pub fn decode(data: &[u8]) -> Result<Instruction, DecodingError> {
                 ))
             }
             0b0000_0001_0000_0000 => return Ok(Instruction::MOVW((d * 2).into(), (r * 2).into())),
-            0b0000_0010_0000_0000 => return Ok(Instruction::MULS((d + 16).into(), (r + 16).into())),
+            0b0000_0010_0000_0000 => {
+                return Ok(Instruction::MULS((d + 16).into(), (r + 16).into()))
+            }
             0b1001_0111_0000_0000 => {
                 return Ok(Instruction::SBIW(
                     ((d & 0b11) * 2 + 24).into(),
                     u16::from(K),
                 ))
             }
-            0b1110_1111_0000_0000 => if r == 0b1111 {
-                return Ok(Instruction::SER((d + 16).into()));
-            },
+            0b1110_1111_0000_0000 => {
+                if r == 0b1111 {
+                    return Ok(Instruction::SER((d + 16).into()));
+                }
+            }
             0b1001_1010_0000_0000 => return Ok(Instruction::SBI(A, b)),
             0b1001_1011_0000_0000 => return Ok(Instruction::SBIS(A, b)),
             0b1001_1001_0000_0000 => return Ok(Instruction::SBIC(A, b)),

src/devices/mod.rs

@@ -2,9 +2,9 @@
 
 use slog::Logger;
 
+pub mod oscillator;
 pub mod ram;
 pub mod usart;
-pub mod oscillator;
 
 pub trait DeviceImpl {
     /// addr relative to the start of the device memory map.
@@ -16,15 +16,15 @@ pub trait DeviceImpl {
 pub struct Device {
     start_addr: u32,
     addr_len: u32,
-    device: Box<DeviceImpl>,
+    device: Box<dyn DeviceImpl>,
 }
 
 impl Device {
-    pub fn new(device: Box<DeviceImpl>, start_addr: u32, addr_len: u32) -> Self {
+    pub fn new<T: DeviceImpl + 'static>(device: T, start_addr: u32, addr_len: u32) -> Self {
         Self {
-            start_addr: start_addr,
-            addr_len: addr_len,
-            device: device,
+            start_addr,
+            addr_len,
+            device: Box::new(device),
         }
     }
 
@@ -49,7 +49,7 @@ pub struct DeviceTree {
 impl DeviceTree {
     pub fn new(log: Logger) -> Self {
         Self {
-            log: log,
+            log,
             devices: Vec::new(),
         }
     }
@@ -59,7 +59,7 @@ impl DeviceTree {
     }
 
     fn get_device_for_addr(&mut self, addr: u32) -> Option<&mut Device> {
-        self.devices.iter_mut().filter(|d| d.handles_addr(addr)).nth(0)
+        self.devices.iter_mut().find(|d| d.handles_addr(addr))
     }
 
     pub fn read(&mut self, addr: u32) -> u8 {
@@ -74,6 +74,9 @@ impl DeviceTree {
         if let Some(ref mut d) = self.get_device_for_addr(addr) {
             return d.write(addr, val);
         }
-        warn!(self.log, "Trying to write unmapped I/O: {:08X} <- {:02X}", addr, val);
+        warn!(
+            self.log,
+            "Trying to write unmapped I/O: {:08X} <- {:02X}", addr, val
+        );
     }
 }

src/devices/oscillator.rs

@@ -6,15 +6,19 @@ const OSC_CTRL: u32 = 0;
 const OSC_STATUS: u32 = 1;
 const OSC_XOSCCTRL: u32 = 2;
 const OSC_XOSCFAIL: u32 = 3;
+/*
 const OSC_RC32KCAL: u32 = 4;
 const OSC_PLLCTRL: u32 = 5;
 const OSC_DFLLCTRL: u32 = 6;
+*/
 
+/*
 enum PllSrc {
     RC2M,
     RC32M,
     XOSC,
 }
+*/
 
 pub struct Oscillator {
     log: Logger,
@@ -24,27 +28,31 @@ pub struct Oscillator {
     ctrl: u8,
     status: u8,
     xoscctrl: u8,
+    /*
     xoscfail: u8,
     rs32kcal: u8,
     pllsrc: PllSrc,
     pllfac: u8,
     dfllctrl: u8,
+    */
 }
 
 impl Oscillator {
     pub fn new(log: Logger) -> Self {
         Self {
-            log: log,
+            log,
             reg_values: [0u8; 7],
 
             ctrl: 0,
             status: 0,
             xoscctrl: 0,
+            /*
             xoscfail: 0,
             rs32kcal: 0,
             pllsrc: PllSrc::RC2M,
             pllfac: 0,
             dfllctrl: 0,
+            */
         }
     }
 }
@@ -74,47 +82,45 @@ impl DeviceImpl for Oscillator {
             OSC_XOSCCTRL => {
                 self.xoscctrl = value & 0xEF;
             }
-            OSC_XOSCFAIL => {
-
-            },
+            OSC_XOSCFAIL => {}
 
             _ => {}
         }
         self.reg_values[addr as usize] = value;
     }
 
-/*
-  } else if(addr == 0x03) { // XOSCFAIL
-    XOSCFAIL vreg;
-    vreg.data = v & 0x03;
-    // XOSCFDEN
-    if(!xoscfail_.xoscfden && vreg.xoscfden) {
-      if(device_->ccpState() & Device::CCP_IOREG) {
-        xoscfail_.xoscfden = 1;
+    /*
+      } else if(addr == 0x03) { // XOSCFAIL
+        XOSCFAIL vreg;
+        vreg.data = v & 0x03;
+        // XOSCFDEN
+        if(!xoscfail_.xoscfden && vreg.xoscfden) {
+          if(device_->ccpState() & Device::CCP_IOREG) {
+            xoscfail_.xoscfden = 1;
+          } else {
+            LOGF(ERROR, "cannot set XOSCFAIL.XOSCFDEN: protected by CCP");
+          }
+        } else if(xoscfail_.xoscfden && !vreg.xoscfden) {
+          LOGF(ERROR, "XOSCFAIL.XOSCFDEN cannot be cleared");
+        }
+        // XOSCFDIF
+        if(vreg.xoscfdif) {
+          xoscfail_.xoscfdif = 0;
+        }
+      } else if(addr == 0x04) { // RC32KCAL
+        rc32kcal_ = v;
+      } else if(addr == 0x05) { // PLLCTRL
+        if((v >> 6) == 1) {
+          LOGF(ERROR, "invalid PLLSRC value");
+        } else {
+          pllsrc_ = static_cast<PLLSRC>(v >> 6);
+        }
+        pllfac_ = v & 0x1F;
+      } else if(addr == 0x06) { // DFLLCTRL
+        //TODO no check nor handling is made here
+        dfllctrl_.data = v & 0x03;
       } else {
-        LOGF(ERROR, "cannot set XOSCFAIL.XOSCFDEN: protected by CCP");
-      }
-    } else if(xoscfail_.xoscfden && !vreg.xoscfden) {
-      LOGF(ERROR, "XOSCFAIL.XOSCFDEN cannot be cleared");
+        LOGF(ERROR, "I/O write %s + 0x%02X: not writable") % name() % addr;
     }
-    // XOSCFDIF
-    if(vreg.xoscfdif) {
-      xoscfail_.xoscfdif = 0;
-    }
-  } else if(addr == 0x04) { // RC32KCAL
-    rc32kcal_ = v;
-  } else if(addr == 0x05) { // PLLCTRL
-    if((v >> 6) == 1) {
-      LOGF(ERROR, "invalid PLLSRC value");
-    } else {
-      pllsrc_ = static_cast<PLLSRC>(v >> 6);
-    }
-    pllfac_ = v & 0x1F;
-  } else if(addr == 0x06) { // DFLLCTRL
-    //TODO no check nor handling is made here
-    dfllctrl_.data = v & 0x03;
-  } else {
-    LOGF(ERROR, "I/O write %s + 0x%02X: not writable") % name() % addr;
-}
-*/
+    */
 }

src/devices/ram.rs

@@ -2,21 +2,21 @@
 use devices::DeviceImpl;
 use slog::Logger;
 
-pub struct RAM {
+pub struct Ram {
     log: Logger,
     data: Box<[u8]>,
 }
 
-impl RAM {
+impl Ram {
     pub fn new(log: Logger) -> Self {
         Self {
-            log: log,
+            log,
             data: Box::new([0u8; 0x4000]),
         }
     }
 }
 
-impl DeviceImpl for RAM {
+impl DeviceImpl for Ram {
     fn read(&mut self, addr: u32) -> u8 {
         self.data[addr as usize]
     }

src/devices/usart.rs

@@ -1,7 +1,7 @@
 use devices::DeviceImpl;
 
-use std;
 use slog::Logger;
+use std;
 
 const USART_DATA: u32 = 0;
 const USART_STATUS: u32 = 1;
@@ -11,7 +11,7 @@ const USART_CTRLC: u32 = 5;
 const USART_BAUDCTRLA: u32 = 6;
 const USART_BAUDCTRLB: u32 = 7;
 
-pub struct USART {
+pub struct Usart {
     /*
     0x8A0: 'USARTC0_DATA',
     0x8A1: 'USARTC0_STATUS',
@@ -31,10 +31,10 @@ pub struct USART {
     baudctrlb: u8,
 }
 
-impl USART {
+impl Usart {
     pub fn new(log: Logger) -> Self {
         Self {
-            log: log,
+            log,
             status: 0,
             ctrla: 0,
             ctrlb: 0,
@@ -45,13 +45,13 @@ impl USART {
     }
 }
 
-impl DeviceImpl for USART {
+impl DeviceImpl for Usart {
     fn read(&mut self, addr: u32) -> u8 {
         match addr {
             USART_DATA => {
                 info!(self.log, "USART::Read(), not implemented");
                 0
-            },
+            }
             USART_STATUS => {
                 // USART_DREIF_bm 0x20
                 /*
@@ -78,23 +78,28 @@ impl DeviceImpl for USART {
                 6547 #define USART_RXB8_bp  0   // Receive Bit 8 bit position.
                 6548
                  */
-                info!(self.log, "Checking USART status");
-                self.status | 0x20u8  // Data register empty flag.
+                info!(self.log, "Checking Usart status");
+                self.status | 0x20u8 // Data register empty flag.
             }
             USART_CTRLA => self.ctrla,
             USART_CTRLB => self.ctrlb,
             USART_CTRLC => self.ctrlc,
             USART_BAUDCTRLA => self.baudctrla,
             USART_BAUDCTRLB => self.baudctrlb,
-            _ => unreachable!()
+            _ => unreachable!(),
         }
     }
 
     fn write(&mut self, addr: u32, value: u8) {
         match addr {
             USART_DATA => {
-                info!(self.log, "USART::Write({} / {:?})", value, std::char::from_u32(u32::from(value)));
-            },
+                info!(
+                    self.log,
+                    "USART::Write({} / {:?})",
+                    value,
+                    std::char::from_u32(u32::from(value))
+                );
+            }
             USART_STATUS => self.status = value,
             USART_CTRLA => self.ctrla = value,
             USART_CTRLB => self.ctrlb = value,
@@ -104,4 +109,4 @@ impl DeviceImpl for USART {
             _ => panic!("Write to usart offset {} <- {:02X}", addr, value),
         }
     }
-}
+}

src/gdbstub.rs

@@ -1,8 +1,8 @@
+use std;
 use std::borrow::Cow;
 use std::collections::HashSet;
-use std;
-use std::net::{TcpListener, TcpStream};
 use std::io::{Read, Write};
+use std::net::{TcpListener, TcpStream};
 
 use slog;
 
@@ -59,7 +59,8 @@ impl GDBPacket {
         let checksum = u8::from_str_radix(
             std::str::from_utf8(&checksum).map_err(|_| (GDBPacketError::InvalidFormat))?,
             16,
-        ).map_err(|_| (GDBPacketError::InvalidFormat))?;
+        )
+        .map_err(|_| (GDBPacketError::InvalidFormat))?;
         let p = GDBPacket {
             raw_data: decoded_data.clone(),
         };
@@ -90,8 +91,7 @@ impl GDBPacket {
     }
 
     pub fn to_packet_format(&self) -> Vec<u8> {
-        let mut r = Vec::new();
-        r.push(b'$');
+        let mut r = vec![b'$'];
         r.extend(self.escaped_data());
         r.push(b'#');
         r.extend(format!("{:02X}", self.gen_checksum()).as_bytes());
@@ -103,7 +103,7 @@ fn split_definitions(pkg: &str) -> Vec<(String, String)> {
     let mut res = Vec::new();
     for definition in pkg.split(';') {
         let mut v = definition.split(':');
-        let first = v.nth(0).unwrap().to_string();
+        let first = v.next().unwrap().to_string();
         res.push((first, v.collect::<String>()));
     }
     res
@@ -123,9 +123,12 @@ impl<'a> GDBStub<'a> {
         format!(
             "T0520:{:02X};21:{:04X};22:{:08X};",
             self.chip.cpu.sreg,
-            self.chip.cpu.get_sp(&mut self.chip.device_tree).swap_bytes(),
+            self.chip
+                .cpu
+                .get_sp(&mut self.chip.device_tree)
+                .swap_bytes(),
             (2 * self.chip.cpu.pc).swap_bytes()
-        ).to_string()
+        )
     }
 
     fn receive_pkg(&self, stream: &mut TcpStream) -> Result<(String, String), ()> {
@@ -167,16 +170,13 @@ impl<'a> GDBStub<'a> {
             .to_string();
 
         // Split it into command and values.
-        if response.chars().nth(0).ok_or(())? == 'v' {
+        if response.chars().next().ok_or(())? == 'v' {
             // Multibyte word, up to the first ; (or others?).
             let word_payload = response.split(';').collect::<Vec<_>>();
-            Ok((
-                word_payload[0].to_string(),
-                word_payload[1..].join(";").to_string(),
-            ))
+            Ok((word_payload[0].to_string(), word_payload[1..].join(";")))
         } else {
             Ok((
-                response.chars().nth(0).ok_or(())?.to_string(),
+                response.chars().next().ok_or(())?.to_string(),
                 response.chars().skip(1).collect::<String>(),
             ))
         }
@@ -184,8 +184,8 @@ impl<'a> GDBStub<'a> {
 
     pub fn new(log: slog::Logger, chip: &'a mut chip::Chip) -> Self {
         Self {
-            log: log,
-            chip: chip,
+            log,
+            chip,
             breakpoints: HashSet::new(),
             watchpoints_read: HashSet::new(),
             watchpoints_write: HashSet::new(),
@@ -194,7 +194,7 @@ impl<'a> GDBStub<'a> {
 
     pub fn run(&mut self, port: u16) {
         let listener = TcpListener::bind(format!("0.0.0.0:{}", port)).unwrap();
-        let mut conn = listener.incoming().nth(0).unwrap().unwrap();
+        let mut conn = listener.incoming().next().unwrap().unwrap();
         info!(self.log, "Debugger attached.");
         // Main debugging loop.
         loop {
@@ -223,8 +223,10 @@ impl<'a> GDBStub<'a> {
                                 </memory></memory-map>",
                                 /*self.chip.ram.len()*/ 0x4000,
                                 self.chip.rom.len()
-                            ).to_string().into();
-                        },
+                            )
+                            .to_string()
+                            .into();
+                        }
                         "C" => response = "01".into(),
                         query => {
                             warn!(self.log, "Unknown query: '{}'", query);
@@ -246,7 +248,10 @@ impl<'a> GDBStub<'a> {
                     // SP
                     reg_vals.push(format!(
                         "{:04X}",
-                        self.chip.cpu.get_sp(&mut self.chip.device_tree).swap_bytes()
+                        self.chip
+                            .cpu
+                            .get_sp(&mut self.chip.device_tree)
+                            .swap_bytes()
                     ));
                     // PC
                     reg_vals.push(format!("{:08X}", (2 * self.chip.cpu.pc).swap_bytes()));
@@ -257,7 +262,7 @@ impl<'a> GDBStub<'a> {
                 "s" | "c" => {
                     // Step / Continue
                     // Parse resume from.
-                    let resume_from = u32::from_str_radix(&*payload, 16);
+                    let resume_from = u32::from_str_radix(&payload, 16);
                     if let Ok(pc) = resume_from {
                         self.chip.cpu.pc = pc;
                     }
@@ -334,7 +339,10 @@ impl<'a> GDBStub<'a> {
                                 err = true;
                                 break;
                             }
-                            self.chip.device_tree.write(addr_i as u32, u8::from_str_radix(&value[2 * i..2 * (i + 1)], 16).unwrap_or(0));
+                            self.chip.device_tree.write(
+                                addr_i as u32,
+                                u8::from_str_radix(&value[2 * i..2 * (i + 1)], 16).unwrap_or(0),
+                            );
                         } else {
                             // ROM
                             if addr >= self.chip.rom.len() {

src/main.rs

@@ -1,8 +1,8 @@
 #![allow(non_snake_case)]
-use std::path::Path;
+use std::fs;
 use std::io;
 use std::io::{Read, Write};
-use std::fs;
+use std::path::Path;
 
 #[macro_use]
 extern crate slog;
@@ -11,13 +11,13 @@ extern crate slog_term;
 
 use slog::Drain;
 
-mod cpu;
-mod regs;
-mod decoder;
-mod devices;
 mod chip;
 mod chip_definitions;
+mod cpu;
+mod decoder;
+mod devices;
 mod gdbstub;
+mod regs;
 
 fn main() {
     let decorator = slog_term::PlainDecorator::new(std::io::stdout());
@@ -34,11 +34,12 @@ fn main() {
         std::env::args()
             .nth(1)
             .unwrap_or_else(|| "rom.bin".to_string()),
-    ).unwrap();
+    )
+    .unwrap();
 
     let mut chip = chip::Chip::new(log.clone(), rom);
 
-    if std::env::args().nth(2).unwrap_or("0".to_string()) == "gdb" {
+    if std::env::args().nth(2).unwrap_or_else(|| "0".to_string()) == "gdb" {
         // Use GDBStub
         info!(log, "Enabling GDB backend");
         gdbstub::run(log.clone(), &mut chip);
@@ -52,14 +53,14 @@ fn main() {
 }
 
 pub fn read_file<P: AsRef<Path>>(rom_path: P) -> Result<Box<[u8]>, io::Error> {
-    let mut file = try!(fs::File::open(rom_path));
+    let mut file = fs::File::open(rom_path)?;
     let mut buf = Vec::new();
-    try!(file.read_to_end(&mut buf));
+    file.read_to_end(&mut buf)?;
     Ok(buf.into_boxed_slice())
 }
 
 pub fn write_file<P: AsRef<Path>>(path: P, data: &[u8]) -> Result<(), io::Error> {
-    let mut file = try!(fs::File::create(path));
-    try!(file.write_all(data));
+    let mut file = fs::File::create(path)?;
+    file.write_all(data)?;
     Ok(())
 }

src/regs.rs

@@ -41,9 +41,9 @@ impl fmt::Display for StatusFlag {
     }
 }
 
-impl Into<u8> for StatusFlag {
-    fn into(self) -> u8 {
-        1 << match self {
+impl From<StatusFlag> for u8 {
+    fn from(sf: StatusFlag) -> u8 {
+        1 << match sf {
             StatusFlag::GlobalInterruptEnable => 7,
             StatusFlag::BitCopyStorage => 6,
             StatusFlag::HalfCarry => 5,
@@ -98,19 +98,18 @@ impl From<u8> for GeneralPurposeRegister {
         if v > 31 {
             unreachable!();
         }
-        Self { 0: v }
+        Self(v)
     }
 }
 
-impl Into<u8> for GeneralPurposeRegister {
-    fn into(self) -> u8 {
-        self.0
+impl From<GeneralPurposeRegister> for u8 {
+    fn from(r: GeneralPurposeRegister) -> u8 {
+        r.0
     }
 }
-
-impl Into<usize> for GeneralPurposeRegister {
-    fn into(self) -> usize {
-        self.0 as usize
+impl From<GeneralPurposeRegister> for usize {
+    fn from(r: GeneralPurposeRegister) -> usize {
+        r.0.into()
     }
 }
 
@@ -142,13 +141,13 @@ impl From<u8> for GeneralPurposeRegisterPair {
             println!("v={}", v);
             unreachable!();
         }
-        Self { 0: v }
+        Self(v)
     }
 }
 
-impl Into<u8> for GeneralPurposeRegisterPair {
-    fn into(self) -> u8 {
-        self.0
+impl From<GeneralPurposeRegisterPair> for u8 {
+    fn from(v: GeneralPurposeRegisterPair) -> u8 {
+        v.0
     }
 }