idea.conf

// system.conf — example Atlas system configuration (ACL2)
// - explicit types
// - arrays (type[])
// - named/repeated blocks (interface "eth0" { ... })
// - expressions, casts, and references ($ = global, $. = local, ^ = parent)
// - semicolons required

System {
    // identity
    string name        = "Atlas";
    string version     = "0.1.0";
    int    build       = 42;

    // runtime behaviour
    bool   debug       = true;
    int    boot_delay  = 200;             // milliseconds
    int    max_procs   = (int)(1.5 * 256); // explicit cast example

    // composite string via expression
    string motd        = "Welcome to " + name + " v" + version + "!";

    // where the real init binary lives inside the image
    string init_path   = "/sbin/init";
}

Kernel {
    string image      = "/boot/vmlinuz";
    string cmdline    = "console=tty0";
    // these flags should match kernel config (prefer builtin for boot-time reliability)
    bool   ext4_builtin = true;
    bool   loop_builtin = true;
}

Init {
    // how many getty ttys the init should spawn
    int spawn_getty_ttys = 3;

    // console device for interactive login
    string console = "/dev/tty1";

    // derive a debug flag from global System.debug
    bool debug_mode = $System.debug;
}

Logging {
    bool   enabled     = true;
    string level       = "INFO";       // "DEBUG" | "INFO" | "WARN" | "ERROR"
    string path        = "/var/log/init.log";
    int    max_size_kb = 10240;        // 10 MiB
}

// Network configuration: multiple interface blocks (repeatable)
Network {
    // named interface block (label is "eth0")
    interface "eth0" {
        string name    = "eth0";
        bool   dhcp    = true;
        string gateway = "192.168.1.1";
        string mtu     = "1500";
    }

    interface "wlan0" {
        string name    = "wlan0";
        bool   dhcp    = false;
        string ip      = "192.168.1.100";
        string netmask = "255.255.255.0";

        // reference the eth0 gateway (global reference)
        string gateway = $Network.interface["eth0"].gateway;
    }

    // static route example, referencing global values
    route "default" {
        string dest = "0.0.0.0/0";
        string via  = $Network.interface["eth0"].gateway;
    }
}

// Modules to preload at early boot
Modules {
    string[] load = { "virtio", "virtio_net", "e1000", "snd_hda_intel" };
}

// Filesystems to mount after pivot/chroot
Filesystems {
    mount "/" {
        string device = "/dev/loop0";
        string fstype = "ext4";
        string opts   = "rw";
    }

    mount "/boot" {
        string device = "/dev/sda1";
        string fstype = "vfat";
        string opts   = "ro";
    }

    // tmpfs example
    tmpfs "/run" {
        int size_kb = 16384;  // 16 MiB
        string opts = "mode=0755";
    }
}

// Services to be supervised by init (simple restart policy)
Services {
    service "netd" {
        string exec   = "/sbin/netd";
        bool   enable = true;
        int    restart_delay_ms = 2000;
        // can refer to modules array length for a derived value
        int    start_order = (int)(1 + 0);  // trivial example expression
    }

    service "getty" {
        string exec   = "/sbin/getty";
        bool   enable = true;
        int    ttys    = $Init.spawn_getty_ttys; // global ref to Init block
    }

    service "sshd" {
        string exec   = "/usr/sbin/sshd";
        bool   enable = true;
        int    restart_delay_ms = 5000;
        // demonstrate local reference usage ($.field refers to same service block)
        string log_path = $Logging.path;
    }
}

// Users: repeated user blocks keyed by login name
Users {
    user "root" {
        string name       = "root";
        int    uid        = 0;
        int    gid        = 0;
        string home       = "/root";
        string shell      = "/bin/sh";
        string passwd_hash = "<hashed-password-placeholder>";
        bool   locked     = false;
    }

    user "alice" {
        string name       = "alice";
        int    uid        = 1000;
        int    gid        = 1000;
        string home       = "/home/alice";
        string shell      = "/bin/sh";
        // demonstrate expression and local reference:
        string welcome_msg = "Hello, " + $.name + " — welcome to " + $System.name + "!";
        bool   locked      = false;
    }
}

// Build/system settings (for self-hosting / in-OS build control)
Build {
    bool   self_host      = true;
    string build_cmd      = "/usr/bin/make -j4";
    string repo_path      = "/usr/src";
    string image_path     = "/atlas.img";

    // a derived rebuild threshold (just to demonstrate expression + cast)
    int    rebuild_threshold_kb = (int)(1024 * 2);  // 2 MiB
    int    rebuild_timeout_ms   = $System.boot_delay * 5;
}

// Simple package manager config (minimal)
PkgManager {
    string db_path    = "/var/lib/atlas/pkgdb";
    string cache_dir  = "/var/cache/atlas";
    bool   auto_upgrade = false;
    string default_repo = "https://packages.atlas.local";  // informational only
}