brightness_manager_config/
brightness_manager_config_rust_config_lib_source.rs
1use fidl::unpersist;
2use fidl_cf_sc_internal_brightnessmanagerconfig::Config as FidlConfig;
3use fuchsia_inspect::Node;
4use fuchsia_runtime::{take_startup_handle, HandleInfo, HandleType};
5use std::convert::TryInto;
6const EXPECTED_CHECKSUM: &[u8] = &[
7 0xe0, 0xaa, 0x2e, 0x12, 0xcb, 0x94, 0x4e, 0xb0, 0x38, 0x64, 0x81, 0xdb, 0x40, 0x90, 0xf0, 0xe3,
8 0x0f, 0xa3, 0xf5, 0x1c, 0xcb, 0x9b, 0x0d, 0x21, 0x5c, 0x29, 0xd8, 0xb7, 0xc5, 0xeb, 0x11, 0xf9,
9];
10#[derive(Debug)]
11pub struct Config {
12 pub manage_display_power: bool,
13 pub power_off_delay_millis: u16,
14 pub power_on_delay_millis: u16,
15}
16impl Config {
17 #[doc = r" Take the config startup handle and parse its contents."]
18 #[doc = r""]
19 #[doc = r" # Panics"]
20 #[doc = r""]
21 #[doc = r" If the config startup handle was already taken or if it is not valid."]
22 pub fn take_from_startup_handle() -> Self {
23 let handle_info = HandleInfo::new(HandleType::ComponentConfigVmo, 0);
24 let config_vmo: zx::Vmo =
25 take_startup_handle(handle_info).expect("Config VMO handle must be present.").into();
26 Self::from_vmo(&config_vmo).expect("Config VMO handle must be valid.")
27 }
28 #[doc = r" Parse `Self` from `vmo`."]
29 pub fn from_vmo(vmo: &zx::Vmo) -> Result<Self, Error> {
30 let config_size = vmo.get_content_size().map_err(Error::GettingContentSize)?;
31 let config_bytes = vmo.read_to_vec(0, config_size).map_err(Error::ReadingConfigBytes)?;
32 Self::from_bytes(&config_bytes)
33 }
34 #[doc = r" Parse `Self` from `bytes`."]
35 pub fn from_bytes(bytes: &[u8]) -> Result<Self, Error> {
36 let (checksum_len_bytes, bytes) = bytes.split_at_checked(2).ok_or(Error::TooFewBytes)?;
37 let checksum_len_bytes: [u8; 2] =
38 checksum_len_bytes.try_into().expect("previous call guaranteed 2 element slice");
39 let checksum_length = u16::from_le_bytes(checksum_len_bytes) as usize;
40 let (observed_checksum, bytes) =
41 bytes.split_at_checked(checksum_length).ok_or(Error::TooFewBytes)?;
42 if observed_checksum != EXPECTED_CHECKSUM {
43 return Err(Error::ChecksumMismatch { observed_checksum: observed_checksum.to_vec() });
44 }
45 let fidl_config: FidlConfig = unpersist(bytes).map_err(Error::Unpersist)?;
46 Ok(Self {
47 manage_display_power: fidl_config.manage_display_power,
48 power_off_delay_millis: fidl_config.power_off_delay_millis,
49 power_on_delay_millis: fidl_config.power_on_delay_millis,
50 })
51 }
52 pub fn record_inspect(&self, inspector_node: &Node) {
53 inspector_node.record_bool("manage_display_power", self.manage_display_power);
54 inspector_node.record_uint("power_off_delay_millis", self.power_off_delay_millis as u64);
55 inspector_node.record_uint("power_on_delay_millis", self.power_on_delay_millis as u64);
56 }
57}
58#[derive(Debug)]
59pub enum Error {
60 #[doc = r" Failed to read the content size of the VMO."]
61 GettingContentSize(zx::Status),
62 #[doc = r" Failed to read the content of the VMO."]
63 ReadingConfigBytes(zx::Status),
64 #[doc = r" The VMO was too small for this config library."]
65 TooFewBytes,
66 #[doc = r" The VMO's config ABI checksum did not match this library's."]
67 ChecksumMismatch { observed_checksum: Vec<u8> },
68 #[doc = r" Failed to parse the non-checksum bytes of the VMO as this library's FIDL type."]
69 Unpersist(fidl::Error),
70}
71impl std::fmt::Display for Error {
72 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
73 match self {
74 Self::GettingContentSize(status) => {
75 write!(f, "Failed to get content size: {status}")
76 }
77 Self::ReadingConfigBytes(status) => {
78 write!(f, "Failed to read VMO content: {status}")
79 }
80 Self::TooFewBytes => {
81 write!(f, "VMO content is not large enough for this config library.")
82 }
83 Self::ChecksumMismatch { observed_checksum } => {
84 write!(
85 f,
86 "ABI checksum mismatch, expected {:?}, got {:?}",
87 EXPECTED_CHECKSUM, observed_checksum,
88 )
89 }
90 Self::Unpersist(fidl_error) => {
91 write!(f, "Failed to parse contents of config VMO: {fidl_error}")
92 }
93 }
94 }
95}
96impl std::error::Error for Error {
97 #[allow(unused_parens, reason = "rustfmt errors without parens here")]
98 fn source(&self) -> Option<(&'_ (dyn std::error::Error + 'static))> {
99 match self {
100 Self::GettingContentSize(ref status) | Self::ReadingConfigBytes(ref status) => {
101 Some(status)
102 }
103 Self::TooFewBytes => None,
104 Self::ChecksumMismatch { .. } => None,
105 Self::Unpersist(ref fidl_error) => Some(fidl_error),
106 }
107 }
108 fn description(&self) -> &str {
109 match self {
110 Self::GettingContentSize(_) => "getting content size",
111 Self::ReadingConfigBytes(_) => "reading VMO contents",
112 Self::TooFewBytes => "VMO contents too small",
113 Self::ChecksumMismatch { .. } => "ABI checksum mismatch",
114 Self::Unpersist(_) => "FIDL parsing error",
115 }
116 }
117}