commit d20b34f9533684edeab295b0a76f3e12620d4e09
Author: Mark Poliakov <mark@alnyan.me>
Date:   Mon Mar 4 17:55:39 2024 +0200

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..1eba605
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "qemu"
+version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..8399fe3
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "qemu"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/src/aarch64.rs b/src/aarch64.rs
new file mode 100644
index 0000000..51e9bc8
--- /dev/null
+++ b/src/aarch64.rs
@@ -0,0 +1,153 @@
+use std::{path::PathBuf, process::Command};
+
+use crate::{Architecture, IntoArgs};
+
+#[derive(Debug)]
+pub enum Machine {
+    Virt { virtualize: bool },
+}
+
+#[derive(Debug)]
+pub enum Cpu {
+    CortexA57,
+}
+
+#[derive(Debug)]
+pub enum Image {
+    Kernel {
+        kernel: PathBuf,
+        initrd: Option<PathBuf>,
+    },
+}
+
+#[derive(Debug)]
+pub struct QemuAArch64;
+
+impl IntoArgs for Machine {
+    fn add_args(&self, command: &mut Command) {
+        command.arg("-M");
+        match self {
+            &Self::Virt { virtualize } => {
+                let mut arg = "virt".to_owned();
+                if virtualize {
+                    arg.push_str(",virtualization=on");
+                }
+                command.arg(arg);
+            }
+        }
+    }
+}
+
+impl IntoArgs for Cpu {
+    fn add_args(&self, command: &mut Command) {
+        command.arg("-cpu");
+        match self {
+            Self::CortexA57 => {
+                command.arg("cortex-a57");
+            }
+        }
+    }
+}
+
+impl IntoArgs for Image {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            Self::Kernel { kernel, initrd } => {
+                command.arg("-kernel").arg(kernel);
+                if let Some(initrd) = initrd {
+                    command.arg("-initrd").arg(initrd);
+                }
+            }
+        }
+    }
+}
+
+impl IntoArgs for QemuAArch64 {
+    fn add_args(&self, _command: &mut Command) {}
+}
+
+impl Architecture for QemuAArch64 {
+    type MachineType = Machine;
+    type CpuType = Cpu;
+    type ImageType = Image;
+
+    const DEFAULT_COMMAND: &'static str = "qemu-system-aarch64";
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{aarch64::Machine, device::QemuSerialTarget, Qemu};
+
+    use super::{Cpu, Image};
+
+    #[test]
+    fn boot_options() {
+        let mut qemu = Qemu::new_aarch64();
+        qemu.with_boot_image(Image::Kernel {
+            kernel: "my-kernel.bin".into(),
+            initrd: Some("my-initrd.img".into()),
+        });
+        let command = qemu.into_command();
+
+        assert_eq!(
+            command.get_args().collect::<Vec<_>>(),
+            vec!["-kernel", "my-kernel.bin", "-initrd", "my-initrd.img"]
+        );
+
+        let mut qemu = Qemu::new_aarch64();
+        qemu.with_boot_image(Image::Kernel {
+            kernel: "my-kernel.bin".into(),
+            initrd: None,
+        });
+        let command = qemu.into_command();
+
+        assert_eq!(
+            command.get_args().collect::<Vec<_>>(),
+            vec!["-kernel", "my-kernel.bin"]
+        );
+    }
+
+    #[test]
+    fn machine_options() {
+        let mut qemu = Qemu::new_aarch64();
+        qemu.with_machine(Machine::Virt { virtualize: true });
+
+        let command = qemu.into_command();
+
+        assert_eq!(
+            command.get_args().collect::<Vec<_>>(),
+            vec!["-M", "virt,virtualization=on"]
+        );
+    }
+
+    #[test]
+    fn full_commands() {
+        let mut qemu = Qemu::new_aarch64();
+        qemu.override_qemu("my-qemu");
+        qemu.with_boot_image(Image::Kernel {
+            kernel: "my-kernel.bin".into(),
+            initrd: Some("my-initrd.img".into()),
+        });
+        qemu.with_machine(Machine::Virt { virtualize: false });
+        qemu.with_cpu(Cpu::CortexA57);
+        qemu.with_serial(QemuSerialTarget::MonStdio);
+
+        let command = qemu.into_command();
+
+        assert_eq!(
+            command.get_args().collect::<Vec<_>>(),
+            vec![
+                "-serial",
+                "mon:stdio",
+                "-M",
+                "virt",
+                "-cpu",
+                "cortex-a57",
+                "-kernel",
+                "my-kernel.bin",
+                "-initrd",
+                "my-initrd.img"
+            ]
+        );
+    }
+}
diff --git a/src/device.rs b/src/device.rs
new file mode 100644
index 0000000..099d3cd
--- /dev/null
+++ b/src/device.rs
@@ -0,0 +1,80 @@
+use std::process::Command;
+
+use crate::IntoArgs;
+
+#[derive(Debug)]
+pub enum QemuNic {
+    VirtioPci { mac: Option<String> },
+}
+
+#[derive(Debug)]
+pub enum QemuDevice {
+    NetworkTap {
+        nic: QemuNic,
+        script: Option<String>,
+        ifname: Option<String>,
+    },
+}
+
+#[derive(Debug)]
+pub enum QemuSerialTarget {
+    MonStdio,
+    Stdio,
+}
+
+impl IntoArgs for QemuNic {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            Self::VirtioPci { mac } => {
+                command.arg("-device");
+                let mut val = "virtio-net-pci,netdev=net0".to_owned();
+                if let Some(mac) = mac {
+                    val.push_str(",mac=");
+                    val.push_str(mac);
+                }
+                command.arg(val);
+            }
+        }
+    }
+}
+
+// TODO separate handling for devices
+impl IntoArgs for QemuDevice {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            Self::NetworkTap {
+                nic,
+                script,
+                ifname,
+            } => {
+                command.arg("-netdev");
+                let mut val = "tap,id=net0".to_owned();
+                if let Some(script) = script {
+                    val.push_str(",script=");
+                    val.push_str(script);
+                }
+                if let Some(ifname) = ifname {
+                    val.push_str(",ifname=");
+                    val.push_str(ifname);
+                }
+                command.arg(val);
+
+                nic.add_args(command);
+            }
+        }
+    }
+}
+
+impl IntoArgs for QemuSerialTarget {
+    fn add_args(&self, command: &mut Command) {
+        command.arg("-serial");
+        match self {
+            Self::MonStdio => {
+                command.arg("mon:stdio");
+            }
+            Self::Stdio => {
+                command.arg("stdio");
+            }
+        }
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..166d09f
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,206 @@
+use std::{fmt::Debug, path::PathBuf, process::Command};
+
+use device::{QemuDevice, QemuSerialTarget};
+
+pub mod aarch64;
+pub mod x86_64;
+
+pub mod device;
+
+pub trait Architecture: IntoArgs {
+    type MachineType: IntoArgs;
+    type CpuType: IntoArgs;
+    type ImageType: IntoArgs;
+
+    const DEFAULT_COMMAND: &'static str;
+}
+
+pub trait IntoArgs {
+    fn add_args(&self, command: &mut Command);
+}
+
+impl<T: IntoArgs> IntoArgs for Option<T> {
+    fn add_args(&self, command: &mut Command) {
+        if let Some(val) = self {
+            val.add_args(command);
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+struct QemuCommon {
+    devices: Vec<QemuDevice>,
+    serial: Option<QemuSerialTarget>,
+}
+
+#[derive(Debug, Default)]
+pub struct Qemu<A: Architecture> {
+    binary_override: Option<PathBuf>,
+    common: QemuCommon,
+    cpu: Option<A::CpuType>,
+    machine: Option<A::MachineType>,
+    boot_image: Option<A::ImageType>,
+    no_display: bool,
+    memory_megabytes: Option<usize>,
+    smp: Option<usize>,
+    arch: A,
+}
+
+impl Qemu<aarch64::QemuAArch64> {
+    pub fn new_aarch64() -> Self {
+        Qemu::new(aarch64::QemuAArch64)
+    }
+}
+
+impl Qemu<x86_64::QemuX86_64> {
+    pub fn new_x86_64() -> Self {
+        Qemu::new(x86_64::QemuX86_64::default())
+    }
+
+    pub fn with_bios_image(&mut self, image: PathBuf) -> &mut Self {
+        self.arch.bios_image = Some(image);
+        self
+    }
+
+    pub fn with_boot_slot(&mut self, slot: char) -> &mut Self {
+        self.arch.boot_slot = Some(slot);
+        self
+    }
+}
+
+impl<A: Architecture> Qemu<A> {
+    pub fn new(arch: A) -> Self {
+        Self {
+            binary_override: None,
+            common: QemuCommon::default(),
+
+            memory_megabytes: None,
+            no_display: false,
+            cpu: None,
+            machine: None,
+            boot_image: None,
+            smp: None,
+            arch,
+        }
+    }
+
+    pub fn with_device(&mut self, device: QemuDevice) -> &mut Self {
+        self.common.devices.push(device);
+        self
+    }
+
+    pub fn with_memory_megabytes(&mut self, value: usize) -> &mut Self {
+        self.memory_megabytes = Some(value);
+        self
+    }
+
+    pub fn with_serial(&mut self, serial: QemuSerialTarget) -> &mut Self {
+        self.common.serial = Some(serial);
+        self
+    }
+
+    pub fn with_boot_image(&mut self, image: A::ImageType) -> &mut Self {
+        self.boot_image = Some(image);
+        self
+    }
+
+    pub fn with_cpu(&mut self, cpu: A::CpuType) -> &mut Self {
+        self.cpu = Some(cpu);
+        self
+    }
+
+    pub fn with_machine(&mut self, machine: A::MachineType) -> &mut Self {
+        self.machine = Some(machine);
+        self
+    }
+
+    pub fn disable_display(&mut self) -> &mut Self {
+        self.no_display = true;
+        self
+    }
+
+    pub fn override_qemu<S: Into<PathBuf>>(&mut self, qemu: S) -> &mut Self {
+        self.binary_override = Some(qemu.into());
+        self
+    }
+
+    pub fn into_command(self) -> Command {
+        let qemu = self
+            .binary_override
+            .clone()
+            .unwrap_or_else(|| A::DEFAULT_COMMAND.into());
+
+        let mut command = Command::new(qemu);
+
+        self.add_args(&mut command);
+
+        command
+    }
+}
+
+impl IntoArgs for QemuCommon {
+    fn add_args(&self, command: &mut Command) {
+        self.serial.add_args(command);
+    }
+}
+
+impl<A: Architecture> IntoArgs for Qemu<A> {
+    fn add_args(&self, command: &mut Command) {
+        self.common.add_args(command);
+
+        for device in &self.common.devices {
+            device.add_args(command);
+        }
+
+        if let Some(mem) = self.memory_megabytes {
+            command.args(["-m", &format!("{}m", mem)]);
+        }
+
+        self.machine.add_args(command);
+        self.cpu.add_args(command);
+        self.boot_image.add_args(command);
+
+        if self.no_display {
+            command.args(["-display", "none"]);
+        }
+
+        if let Some(smp) = self.smp {
+            command.args(["-smp", &format!("{}", smp)]);
+        }
+
+        self.arch.add_args(command);
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{device::QemuSerialTarget, Qemu};
+
+    #[test]
+    fn empty() {
+        let builder = Qemu::new_aarch64();
+        let command = builder.into_command();
+        assert_eq!(command.get_program(), "qemu-system-aarch64");
+        assert_eq!(command.get_args().len(), 0);
+    }
+
+    #[test]
+    fn qemu_override() {
+        let mut qemu = Qemu::new_aarch64();
+        qemu.override_qemu("test-qemu");
+        let command = qemu.into_command();
+        assert_eq!(command.get_program(), "test-qemu");
+    }
+
+    #[test]
+    fn common_options() {
+        let mut qemu = Qemu::new_aarch64();
+        qemu.with_serial(QemuSerialTarget::MonStdio);
+        let command = qemu.into_command();
+
+        assert_eq!(
+            command.get_args().collect::<Vec<_>>(),
+            vec!["-serial", "mon:stdio"]
+        );
+    }
+}
diff --git a/src/x86_64.rs b/src/x86_64.rs
new file mode 100644
index 0000000..2121b5e
--- /dev/null
+++ b/src/x86_64.rs
@@ -0,0 +1,84 @@
+use std::{path::PathBuf, process::Command};
+
+use crate::{Architecture, IntoArgs};
+
+#[derive(Debug)]
+pub enum Machine {
+    Q35,
+}
+
+#[derive(Debug)]
+pub enum Cpu {
+    Host { enable_kvm: bool },
+}
+
+#[derive(Debug)]
+pub enum Image {
+    Drive(PathBuf),
+}
+
+#[derive(Debug, Default)]
+pub struct QemuX86_64 {
+    pub bios_image: Option<PathBuf>,
+    pub boot_slot: Option<char>,
+}
+
+impl IntoArgs for Machine {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            Self::Q35 => {
+                command.args(["-M", "q35"]);
+            }
+        }
+    }
+}
+
+impl IntoArgs for Cpu {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            &Self::Host { enable_kvm } => {
+                command.args(["-cpu", "host"]);
+                if enable_kvm {
+                    command.arg("-enable-kvm");
+                }
+            }
+        }
+    }
+}
+
+impl IntoArgs for Image {
+    fn add_args(&self, command: &mut Command) {
+        match self {
+            Self::Drive(path) => {
+                command.args(["-drive", &format!("format=raw,file={}", path.display())]);
+            }
+        }
+    }
+}
+
+impl IntoArgs for QemuX86_64 {
+    fn add_args(&self, command: &mut Command) {
+        if let Some(slot) = self.boot_slot {
+            command.arg("-boot");
+            command.arg(format!("{}", slot));
+        }
+
+        if let Some(bios_image) = self.bios_image.as_ref() {
+            command.args([
+                "-drive",
+                &format!(
+                    "format=raw,if=pflash,readonly=on,file={}",
+                    bios_image.display()
+                ),
+            ]);
+        }
+    }
+}
+
+impl Architecture for QemuX86_64 {
+    type MachineType = Machine;
+    type CpuType = Cpu;
+    type ImageType = Image;
+
+    const DEFAULT_COMMAND: &'static str = "qemu-system-x86_64";
+}