starnix_kernel_structured_config/
starnix_kernel_structured_config_rust_config_lib_source.rs

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use fidl::unpersist;
use fidl_cf_sc_internal_starnixkernelstructuredconfig::Config as FidlConfig;
use fuchsia_inspect::Node;
use fuchsia_runtime::{take_startup_handle, HandleInfo, HandleType};
#[derive(Debug)]
pub struct Config {
    pub ui_visual_debugging_level: u8,
}
impl Config {
    pub fn take_from_startup_handle() -> Self {
        let config_vmo: zx::Vmo =
            take_startup_handle(HandleInfo::new(HandleType::ComponentConfigVmo, 0))
                .expect("Config VMO handle must be provided and cannot already have been taken.")
                .into();
        let config_size =
            config_vmo.get_content_size().expect("must be able to read config vmo content size");
        assert_ne!(config_size, 0, "config vmo must be non-empty");
        let config_bytes =
            config_vmo.read_to_vec(0, config_size).expect("must be able to read config vmo");
        let checksum_length = u16::from_le_bytes([config_bytes[0], config_bytes[1]]) as usize;
        let fidl_start = 2 + checksum_length;
        let observed_checksum = &config_bytes[2..fidl_start];
        let expected_checksum = vec![
            0x16, 0x92, 0xc0, 0xf9, 0x5f, 0xa8, 0xae, 0xce, 0xb7, 0xa9, 0xf6, 0x06, 0x14, 0x9b,
            0x7a, 0x2f, 0xa4, 0xf7, 0x90, 0xb7, 0x48, 0xfa, 0x26, 0xf4, 0xa6, 0x0c, 0x1f, 0x7d,
            0xc3, 0xd0, 0xd4, 0x53,
        ];
        assert_eq!(
            observed_checksum, expected_checksum,
            "checksum from config VMO does not match expected checksum"
        );
        let fidl_config: FidlConfig = unpersist(&config_bytes[fidl_start..])
            .expect("must be able to parse bytes as config FIDL");
        Self { ui_visual_debugging_level: fidl_config.ui_visual_debugging_level }
    }
    pub fn record_inspect(&self, inspector_node: &Node) {
        inspector_node
            .record_uint("ui_visual_debugging_level", self.ui_visual_debugging_level as u64);
    }
}