## Motivation
Currently, compiling `tracing-core` with `default-features = false`
(i.e. for `no_std` targets) emits a few warnings. This is due to the
spinlock implementation's use of the deprecated `atomic::spin_loop_hint`
function (renamed to `hint::spin_loop`), and the use of deprecated
`compare_and_swap` instead of `compare_exchange` methods. Now that our
MSRV is 1.49 (the version in which `hint::spin_loop` was stabilized), we
can fix these warnings.
## Solution
This branch replaces the deprecated APIs.
Also, I noticed that one of the tests emits unused-imports warnings with
`--no-default-features`. This is because the actual tests are feature
flagged to require `std`, but the module itself doesn't, so the imports
are just hanging out and not getting used for anything. I went ahead and
fixed that as well.
Signed-off-by: Eliza Weisman <eliza@buoyant.io>
## Motivation
As discussed in #383 , adds the new `set_default` method.
## Solution
* Add `tracing::subscriber::set_default` which sets the default
subscriber and returns a drop guard. This drop guard will reset the
dispatch on drop.
* Add `tracing_core::dispatcher::set_default` method which sets the
default dispatch and returns a drop guard.
* Update `tracing_core::dispatcher::with_default` method to use the new
`tracing_core::dispatcher::set_default` method.
* Add test to confirm expected behavior
Fixes: #383
* core: support `no-std` + `alloc`
Motivation
Users have expressed interest in using `tracing` on no_std platforms
with `liballoc`.
Solution
This branch adds `no_std` support to `tracing-core` by adding a `std`
feature flag (on by default) which can be disabled to use `libcore` +
`liballoc` instead of `libstd`.
When the `std` feature is disabled, `tracing-core` will use
`spin::Mutex` rather than `std::sync::Mutex`, and the thread-local
scoped dispatcher will be disabled (since it necessitates a defined OS
threading model, which may not exist on `no_std` platforms).
Refs: #213
Signed-off-by: Eliza Weisman <eliza@buoyant.io>
See #95
This branch renames everything from `tokio-trace` to `tracing`.
Unlike PR #98, the nursery crates still depend on the crates.io
versions of `tokio-trace` and `tokio-trace-core`, but renamed
to `tracing`/`tracing-core` in `Cargo.toml`. We can update the
nursery crates to depend on local path dependencies in a
subsequent PR, as that will require making code changes to the
nursery crates.
This branch _also_ updates the minimum Rust version to 1.34.0,
to the shock and horror of the millions of `tracing` users still
on Rust 1.26.0. This was necessary in order to allow renaming
crates in `Cargo.toml`, and to resolve that not using the `dyn`
keyword is now a warning on nightly.
Closes#98Closes#95
Signed-off-by: Eliza Weisman <eliza@buoyant.io>
