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use fidl::encoding::unpersist;
use fidl_cf_sc_internal_pkgcacheconfig::Config as FidlConfig;
use fuchsia_inspect::Node;
use fuchsia_runtime::{take_startup_handle, HandleInfo, HandleType};
use fuchsia_zircon as zx;
#[derive(Debug)]
pub struct Config {
pub use_system_image: bool,
}
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 mut config_bytes = Vec::new();
config_bytes.resize(config_size as usize, 0);
config_vmo.read(&mut config_bytes, 0).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![
0xc2, 0xbd, 0xaa, 0x44, 0x24, 0x65, 0x4f, 0x2e, 0x24, 0xce, 0x99, 0x82, 0x3f, 0xa9,
0x2b, 0x48, 0x09, 0x72, 0xae, 0x14, 0xad, 0x43, 0xc7, 0x8b, 0x0b, 0xbd, 0x9c, 0xf3,
0xa8, 0x0b, 0x95, 0x1c,
];
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 { use_system_image: fidl_config.use_system_image }
}
pub fn record_inspect(&self, inspector_node: &Node) {
inspector_node.record_bool("use_system_image", self.use_system_image);
}
}