Struct ServerEnv 

pub struct ServerEnv { /* private fields */ }

Environment variable overrides for a server process.

Holds at most one key per variable as the host compares names (exactly on Unix, case-insensitively as Windows compares names): the table is indexed by the host’s comparison of the name, so a lookup or a write cannot meet two spellings of one variable and mcpls resolves the same value the child process sees. The host is fixed at construction, so a table built for one host cannot be read or extended as another. Keys come in through Self::from_entries, which rejects collisions, or Self::insert, which replaces them. Neither lets the table outgrow what the host can pass to a process: HostOs::max_env_entry_bytes for one entry and MAX_ENV_TOTAL_BYTES for all.

The host is not serialized: a deserialized table is always for HostOs::CURRENT, and converting into a map drops it. Other hosts exist so tests can model them (Windows name folding on any build).

Examples

use mcpls_core::config::{EnvKey, EnvValue, HostOs, ServerEnv};

let mut env = ServerEnv::new(HostOs::Windows);
env.insert(EnvKey::new("Path").unwrap(), EnvValue::new("/a").unwrap())?;
assert_eq!(env.get("PATH"), Some("/a"));

env.insert(EnvKey::new("PATH").unwrap(), EnvValue::new("/b").unwrap())?;
assert_eq!(env.len(), 1);

let mut other = ServerEnv::new(HostOs::Other);
other.insert(EnvKey::new("Path").unwrap(), EnvValue::new("/a").unwrap())?;
assert_eq!(other.get("PATH"), None);

Implementations

impl ServerEnv

pub const fn new(host: HostOs) -> Self

An empty table whose names compare as host compares them.

pub fn from_entries( entries: impl IntoIterator<Item = (EnvKey, EnvValue)>, host: HostOs, ) -> Result<Self, InvalidServerEnv>

Builds the table from entries, as host compares names.

Errors

InvalidServerEnv::Duplicate when two keys name one variable on host, InvalidServerEnv::TooLarge when an entry or the table is too large to pass to a process there.

pub const fn host(&self) -> HostOs

The host whose name comparison this table follows.

pub fn get(&self, key: &str) -> Option<&str>

The value of key, looked up as the table’s host compares names.

pub fn contains_key(&self, key: &str) -> bool

Whether key is set, as the table’s host compares names.

pub fn insert( &mut self, key: EnvKey, value: EnvValue, ) -> Result<(), EnvTooLarge>

Sets key, replacing the spelling of it that the table’s host treats as the same variable.

Errors

EnvTooLarge when the entry is over HostOs::max_env_entry_bytes or the table would be over MAX_ENV_TOTAL_BYTES, the sizes past which a spawn fails with E2BIG; the table is left as it was.

pub fn iter(&self) -> impl Iterator<Item = (&EnvKey, &EnvValue)>

The entries, ordered by the host’s comparison of the name.

pub fn len(&self) -> usize

The number of variables set.

pub fn is_empty(&self) -> bool

Whether no variable is set.

Trait Implementations

impl Clone for ServerEnv

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ServerEnv

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ServerEnv

An empty table for HostOs::CURRENT.

fn default() -> Self

Returns the “default value” for a type.

impl Eq for ServerEnv

impl From<ServerEnv> for BTreeMap<EnvKey, String>

The entries without the table’s host, which is not serialized.

fn from(env: ServerEnv) -> Self

Converts to this type from the input type.

impl PartialEq for ServerEnv

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ServerEnv