counter_config/
config_lib_rust_config_lib_source.rs

1use fidl::unpersist;
2use fidl_cf_sc_internal_counterconfig::Config as FidlConfig;
3use fuchsia_inspect::Node;
4use fuchsia_runtime::{take_startup_handle, HandleInfo, HandleType};
5#[derive(Debug)]
6pub struct Config {
7    pub routed_config: bool,
8    pub starting_value: u32,
9}
10impl Config {
11    pub fn take_from_startup_handle() -> Self {
12        let config_vmo: zx::Vmo =
13            take_startup_handle(HandleInfo::new(HandleType::ComponentConfigVmo, 0))
14                .expect("Config VMO handle must be provided and cannot already have been taken.")
15                .into();
16        let config_size =
17            config_vmo.get_content_size().expect("must be able to read config vmo content size");
18        assert_ne!(config_size, 0, "config vmo must be non-empty");
19        let config_bytes =
20            config_vmo.read_to_vec(0, config_size).expect("must be able to read config vmo");
21        let checksum_length = u16::from_le_bytes([config_bytes[0], config_bytes[1]]) as usize;
22        let fidl_start = 2 + checksum_length;
23        let observed_checksum = &config_bytes[2..fidl_start];
24        let expected_checksum = vec![
25            0x8c, 0x34, 0x33, 0xab, 0x56, 0x0b, 0xac, 0xac, 0x14, 0x25, 0x4f, 0x40, 0xdf, 0x8e,
26            0x3d, 0x6a, 0x6d, 0x4d, 0xbb, 0x21, 0x16, 0xdf, 0x2b, 0x49, 0x49, 0xc0, 0x6a, 0x44,
27            0x08, 0x94, 0x27, 0xae,
28        ];
29        assert_eq!(
30            observed_checksum, expected_checksum,
31            "checksum from config VMO does not match expected checksum"
32        );
33        let fidl_config: FidlConfig = unpersist(&config_bytes[fidl_start..])
34            .expect("must be able to parse bytes as config FIDL");
35        Self {
36            routed_config: fidl_config.routed_config,
37            starting_value: fidl_config.starting_value,
38        }
39    }
40    pub fn record_inspect(&self, inspector_node: &Node) {
41        inspector_node.record_bool("routed_config", self.routed_config);
42        inspector_node.record_uint("starting_value", self.starting_value as u64);
43    }
44}
counter_config/config_lib_rust_config_lib_source.rs

counter_config/
config_lib_rust_config_lib_source.rs
