From cf94bdc0742c13e2a0cac864c478b8626b266e1b Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:11:38 +0200 Subject: Merging upstream version 1.66.0+dfsg1. Signed-off-by: Daniel Baumann --- vendor/tracing-subscriber/src/reload.rs | 360 -------------------------------- 1 file changed, 360 deletions(-) delete mode 100644 vendor/tracing-subscriber/src/reload.rs (limited to 'vendor/tracing-subscriber/src/reload.rs') diff --git a/vendor/tracing-subscriber/src/reload.rs b/vendor/tracing-subscriber/src/reload.rs deleted file mode 100644 index 0c6c1c45c..000000000 --- a/vendor/tracing-subscriber/src/reload.rs +++ /dev/null @@ -1,360 +0,0 @@ -//! Wrapper for a `Layer` to allow it to be dynamically reloaded. -//! -//! This module provides a [`Layer` type] implementing the [`Layer` trait] or [`Filter` trait] -//! which wraps another type implementing the corresponding trait. This -//! allows the wrapped type to be replaced with another -//! instance of that type at runtime. -//! -//! This can be used in cases where a subset of `Layer` or `Filter` functionality -//! should be dynamically reconfigured, such as when filtering directives may -//! change at runtime. Note that this layer introduces a (relatively small) -//! amount of overhead, and should thus only be used as needed. -//! -//! # Examples -//! -//! Reloading a [global filtering](crate::layer#global-filtering) layer: -//! -//! ```rust -//! # use tracing::info; -//! use tracing_subscriber::{filter, fmt, reload, prelude::*}; -//! let filter = filter::LevelFilter::WARN; -//! let (filter, reload_handle) = reload::Layer::new(filter); -//! tracing_subscriber::registry() -//! .with(filter) -//! .with(fmt::Layer::default()) -//! .init(); -//! # -//! # // specifying the Registry type is required -//! # let _: &reload::Handle = &reload_handle; -//! # -//! info!("This will be ignored"); -//! reload_handle.modify(|filter| *filter = filter::LevelFilter::INFO); -//! info!("This will be logged"); -//! ``` -//! -//! Reloading a [`Filtered`](crate::filter::Filtered) layer: -//! -//! ```rust -//! # use tracing::info; -//! use tracing_subscriber::{filter, fmt, reload, prelude::*}; -//! let filtered_layer = fmt::Layer::default().with_filter(filter::LevelFilter::WARN); -//! let (filtered_layer, reload_handle) = reload::Layer::new(filtered_layer); -//! # -//! # // specifying the Registry type is required -//! # let _: &reload::Handle, -//! # filter::LevelFilter, tracing_subscriber::Registry>,tracing_subscriber::Registry> -//! # = &reload_handle; -//! # -//! tracing_subscriber::registry() -//! .with(filtered_layer) -//! .init(); -//! info!("This will be ignored"); -//! reload_handle.modify(|layer| *layer.filter_mut() = filter::LevelFilter::INFO); -//! info!("This will be logged"); -//! ``` -//! -//! ## Note -//! -//! The [`Layer`] implementation is unable to implement downcasting functionality, -//! so certain [`Layer`] will fail to downcast if wrapped in a `reload::Layer`. -//! -//! If you only want to be able to dynamically change the -//! `Filter` on a layer, prefer wrapping that `Filter` in the `reload::Layer`. -//! -//! [`Filter` trait]: crate::layer::Filter -//! [`Layer` type]: Layer -//! [`Layer` trait]: super::layer::Layer -use crate::layer; -use crate::sync::RwLock; - -use std::{ - error, fmt, - marker::PhantomData, - sync::{Arc, Weak}, -}; -use tracing_core::{ - callsite, span, - subscriber::{Interest, Subscriber}, - Event, LevelFilter, Metadata, -}; - -/// Wraps a `Layer` or `Filter`, allowing it to be reloaded dynamically at runtime. -#[derive(Debug)] -pub struct Layer { - // TODO(eliza): this once used a `crossbeam_util::ShardedRwLock`. We may - // eventually wish to replace it with a sharded lock implementation on top - // of our internal `RwLock` wrapper type. If possible, we should profile - // this first to determine if it's necessary. - inner: Arc>, - _s: PhantomData, -} - -/// Allows reloading the state of an associated [`Layer`](crate::layer::Layer). -#[derive(Debug)] -pub struct Handle { - inner: Weak>, - _s: PhantomData, -} - -/// Indicates that an error occurred when reloading a layer. -#[derive(Debug)] -pub struct Error { - kind: ErrorKind, -} - -#[derive(Debug)] -enum ErrorKind { - SubscriberGone, - Poisoned, -} - -// ===== impl Layer ===== - -impl crate::Layer for Layer -where - L: crate::Layer + 'static, - S: Subscriber, -{ - fn on_layer(&mut self, subscriber: &mut S) { - try_lock!(self.inner.write(), else return).on_layer(subscriber); - } - - #[inline] - fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest { - try_lock!(self.inner.read(), else return Interest::sometimes()).register_callsite(metadata) - } - - #[inline] - fn enabled(&self, metadata: &Metadata<'_>, ctx: layer::Context<'_, S>) -> bool { - try_lock!(self.inner.read(), else return false).enabled(metadata, ctx) - } - - #[inline] - fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_new_span(attrs, id, ctx) - } - - #[inline] - fn on_record(&self, span: &span::Id, values: &span::Record<'_>, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_record(span, values, ctx) - } - - #[inline] - fn on_follows_from(&self, span: &span::Id, follows: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_follows_from(span, follows, ctx) - } - - #[inline] - fn event_enabled(&self, event: &Event<'_>, ctx: layer::Context<'_, S>) -> bool { - try_lock!(self.inner.read(), else return false).event_enabled(event, ctx) - } - - #[inline] - fn on_event(&self, event: &Event<'_>, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_event(event, ctx) - } - - #[inline] - fn on_enter(&self, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_enter(id, ctx) - } - - #[inline] - fn on_exit(&self, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_exit(id, ctx) - } - - #[inline] - fn on_close(&self, id: span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_close(id, ctx) - } - - #[inline] - fn on_id_change(&self, old: &span::Id, new: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_id_change(old, new, ctx) - } - - #[inline] - fn max_level_hint(&self) -> Option { - try_lock!(self.inner.read(), else return None).max_level_hint() - } -} - -// ===== impl Filter ===== - -#[cfg(all(feature = "registry", feature = "std"))] -#[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))] -impl crate::layer::Filter for Layer -where - L: crate::layer::Filter + 'static, - S: Subscriber, -{ - #[inline] - fn callsite_enabled(&self, metadata: &'static Metadata<'static>) -> Interest { - try_lock!(self.inner.read(), else return Interest::sometimes()).callsite_enabled(metadata) - } - - #[inline] - fn enabled(&self, metadata: &Metadata<'_>, ctx: &layer::Context<'_, S>) -> bool { - try_lock!(self.inner.read(), else return false).enabled(metadata, ctx) - } - - #[inline] - fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_new_span(attrs, id, ctx) - } - - #[inline] - fn on_record(&self, span: &span::Id, values: &span::Record<'_>, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_record(span, values, ctx) - } - - #[inline] - fn on_enter(&self, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_enter(id, ctx) - } - - #[inline] - fn on_exit(&self, id: &span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_exit(id, ctx) - } - - #[inline] - fn on_close(&self, id: span::Id, ctx: layer::Context<'_, S>) { - try_lock!(self.inner.read()).on_close(id, ctx) - } - - #[inline] - fn max_level_hint(&self) -> Option { - try_lock!(self.inner.read(), else return None).max_level_hint() - } -} - -impl Layer { - /// Wraps the given [`Layer`] or [`Filter`], returning a `reload::Layer` - /// and a `Handle` that allows the inner value to be modified at runtime. - /// - /// [`Layer`]: crate::layer::Layer - /// [`Filter`]: crate::layer::Filter - pub fn new(inner: L) -> (Self, Handle) { - let this = Self { - inner: Arc::new(RwLock::new(inner)), - _s: PhantomData, - }; - let handle = this.handle(); - (this, handle) - } - - /// Returns a `Handle` that can be used to reload the wrapped [`Layer`] or [`Filter`]. - /// - /// [`Layer`]: crate::layer::Layer - /// [`Filter`]: crate::filter::Filter - pub fn handle(&self) -> Handle { - Handle { - inner: Arc::downgrade(&self.inner), - _s: PhantomData, - } - } -} - -// ===== impl Handle ===== - -impl Handle { - /// Replace the current [`Layer`] or [`Filter`] with the provided `new_value`. - /// - /// [`Handle::reload`] cannot be used with the [`Filtered`] layer; use - /// [`Handle::modify`] instead (see [this issue] for additional details). - /// - /// However, if the _only_ the [`Filter`] needs to be modified, use - /// `reload::Layer` to wrap the `Filter` directly. - /// - /// [`Layer`]: crate::layer::Layer - /// [`Filter`]: crate::layer::Filter - /// [`Filtered`]: crate::filter::Filtered - /// - /// [this issue]: https://github.com/tokio-rs/tracing/issues/1629 - pub fn reload(&self, new_value: impl Into) -> Result<(), Error> { - self.modify(|layer| { - *layer = new_value.into(); - }) - } - - /// Invokes a closure with a mutable reference to the current layer or filter, - /// allowing it to be modified in place. - pub fn modify(&self, f: impl FnOnce(&mut L)) -> Result<(), Error> { - let inner = self.inner.upgrade().ok_or(Error { - kind: ErrorKind::SubscriberGone, - })?; - - let mut lock = try_lock!(inner.write(), else return Err(Error::poisoned())); - f(&mut *lock); - // Release the lock before rebuilding the interest cache, as that - // function will lock the new layer. - drop(lock); - - callsite::rebuild_interest_cache(); - Ok(()) - } - - /// Returns a clone of the layer or filter's current value if it still exists. - /// Otherwise, if the subscriber has been dropped, returns `None`. - pub fn clone_current(&self) -> Option - where - L: Clone, - { - self.with_current(L::clone).ok() - } - - /// Invokes a closure with a borrowed reference to the current layer or filter, - /// returning the result (or an error if the subscriber no longer exists). - pub fn with_current(&self, f: impl FnOnce(&L) -> T) -> Result { - let inner = self.inner.upgrade().ok_or(Error { - kind: ErrorKind::SubscriberGone, - })?; - let inner = try_lock!(inner.read(), else return Err(Error::poisoned())); - Ok(f(&*inner)) - } -} - -impl Clone for Handle { - fn clone(&self) -> Self { - Handle { - inner: self.inner.clone(), - _s: PhantomData, - } - } -} - -// ===== impl Error ===== - -impl Error { - fn poisoned() -> Self { - Self { - kind: ErrorKind::Poisoned, - } - } - - /// Returns `true` if this error occurred because the layer was poisoned by - /// a panic on another thread. - pub fn is_poisoned(&self) -> bool { - matches!(self.kind, ErrorKind::Poisoned) - } - - /// Returns `true` if this error occurred because the `Subscriber` - /// containing the reloadable layer was dropped. - pub fn is_dropped(&self) -> bool { - matches!(self.kind, ErrorKind::SubscriberGone) - } -} - -impl fmt::Display for Error { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - let msg = match self.kind { - ErrorKind::SubscriberGone => "subscriber no longer exists", - ErrorKind::Poisoned => "lock poisoned", - }; - f.pad(msg) - } -} - -impl error::Error for Error {} -- cgit v1.2.3