Merge #176

176:  implement RFCs 147 and 155, fix #141, etc. r=japaric a=japaric

This PR:

- Implements RFC 147: "all functions must be safe"

- Implements RFC 155: "explicit Context parameter"

- Implements the pending breaking change #141: reject assign syntax in `init`
  (which was used to initialize late resources)

- Refactors code generation to make it more readable -- there are no more random
  identifiers in the output -- and align it with the book description of RTFM
  internals (see PR #175).

- Makes the framework hard depend on `core::mem::MaybeUninit` and thus will
  require nightly until that API is stabilized.

- Fixes a ceiling analysis bug where the priority of the system timer was not
  considered in the analysis (TODO backport this into the v0.4.x branch).

- Shrinks the size of all the internal queues by turning `AtomicUsize` indices
  into `AtomicU8`s.

- Removes the integration with `owned_singleton`.

closes #141
closes #147
closes #155

Additionally:

- This changes CI to push v0.5.x docs to
  https://japaric.github.io/rtfm5/book/en/ -- we need to do this because our
  official docs are hosted on https://japaric.github.io/cortex-m-rtfm and we
  need to keep them on v0.4.x until we release v0.5.0

- I propose that we use the master branch to develop the upcoming v0.5.0.

- I have created a branch v0.4.x for backports; new v0.4.x releases will come
  from that branch.

r? @korken89 @texitoi, sorry for doing all the impl work in a single commit --
I know that makes things harder to review for you.

Suggestions for compile-pass and compile-fail tests are welcome


Co-authored-by: Jorge Aparicio <jorge@japaric.io>

1 files changed, 5 insertions, 6 deletions

diff --git a/book/en/src/by-example/app.md b/book/en/src/by-example/app.md
index 996b8c1..d595570 100644
--- a/book/en/src/by-example/app.md
+++ b/book/en/src/by-example/app.md
@@ -28,15 +28,14 @@ not required to use the [`cortex_m_rt::entry`] attribute.
 
 Within the pseudo-module the `app` attribute expects to find an initialization
 function marked with the `init` attribute. This function must have signature
-`[unsafe] fn()`.
+`fn(init::Context) [-> init::LateResources]`.
 
 This initialization function will be the first part of the application to run.
 The `init` function will run *with interrupts disabled* and has exclusive access
 to Cortex-M and device specific peripherals through the `core` and `device`
-variables, which are injected in the scope of `init` by the `app` attribute. Not
-all Cortex-M peripherals are available in `core` because the RTFM runtime takes
-ownership of some of them -- for more details see the [`rtfm::Peripherals`]
-struct.
+variables fields of `init::Context`. Not all Cortex-M peripherals are available
+in `core` because the RTFM runtime takes ownership of some of them -- for more
+details see the [`rtfm::Peripherals`] struct.
 
 `static mut` variables declared at the beginning of `init` will be transformed
 into `&'static mut` references that are safe to access.
@@ -61,7 +60,7 @@ $ cargo run --example init
 
 A function marked with the `idle` attribute can optionally appear in the
 pseudo-module. This function is used as the special *idle task* and must have
-signature `[unsafe] fn() - > !`.
+signature `fn(idle::Context) - > !`.
 
 When present, the runtime will execute the `idle` task after `init`. Unlike
 `init`, `idle` will run *with interrupts enabled* and it's not allowed to return