Struct ForwardPolicy 

pub struct ForwardPolicy { /* private fields */ }

Which emitting modules a forwarded process may send DETLOG records from.

WHY THIS IS NEEDED. In-process, detlog! asks tracing whether INFO is enabled at its own callsite, whose target is the emitting module’s path, so a target-scoped filter such as RUST_LOG=warn,detcore::random=info keeps the detcore::random records and drops the rest. A tool running in another process (SaBRe’s guest plugin) has no subscriber to ask, so the coordinator must hand it the same per-target answer. A single yes/no for the whole detcore target either drops the scoped records or emits records the coordinator’s filter suppresses; both make the backends’ logs disagree.

The policy holds the coordinator’s answer at a default target that no directive names and at every target a directive names. Its answer for a record is the entry for the longest named target that is a string prefix of the record’s target, else the default. That is tracing-subscriber’s rule for target directives: the most specific matching directive decides, and any target a directive could match through is itself an entry here.

Limit: directives that select by span ([syscall.intercept]=info, or a field filter with a value, which matches span fields) decide per record from the spans the emitting thread has entered. Those spans exist only in the process where the coordinator’s subscriber runs (under ptrace, reverie-ptrace enters syscall.intercept around each Detcore callback); a forwarded process has none, so this per-target answer, taken once at launch, cannot reproduce them. Target directives and field-presence filters are reproduced exactly.

Implementations

impl ForwardPolicy

pub fn all() -> Self

Forward every record. This is the policy the historical encoding 1 denoted, and the one a coordinator logging all of Detcore at INFO sends.

pub fn from_current_subscriber(directives: &str) -> Self

Ask the current tracing subscriber which targets it takes INFO records from.

directives is the filter text the subscriber was built from (for the CLI, RUST_LOG). Only the target names are read from it; whether each is enabled is asked of the subscriber, so level overrides added after the text (--log) are honoured. Unparseable or extra names are harmless: probing a target no directive names returns that target’s true answer.

pub fn from_probe(directives: &str, info_enabled: impl Fn(&str) -> bool) -> Self

Build a policy from directives’ target names and an INFO probe.

pub fn forwards_any(&self) -> bool

Whether any record could be forwarded under this policy.

pub fn forwards(&self, target: &str) -> bool

Whether a record emitted by module target is forwarded.

pub fn encode(&self) -> String

Encode for an environment variable: the default (1 or 0) followed by ,target=1 or ,target=0 per named target. Directive targets cannot contain , or =. 1 alone is the historical forward-everything value.

pub fn decode(encoded: &str) -> Result<Self, String>

Decode ForwardPolicy::encode’s output, refusing anything else.

Trait Implementations

impl Clone for ForwardPolicy

fn clone(&self) -> ForwardPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ForwardPolicy

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

Formats the value using the given formatter.

impl Eq for ForwardPolicy

impl PartialEq for ForwardPolicy

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ForwardPolicy