Merge #447

447: Add implementation for critical-section 1.0 r=adamgreig a=Dirbaio

Picking up #433 since it seems stalled. Changes from #433 are:
- Update to `critical-section 1.0.0-alpha.2`
- Use `bool` restore token
- Name Cargo feature `critical-section-single-core`.

TODO before merging:

- [x] Wait for `critical-section 1.0` release https://github.com/rust-embedded/critical-section/pull/19

Co-Authored-By: Markus Reiter `@reitermarkus` 

Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>

2 files changed, 5 insertions, 6 deletions

diff --git a/cortex-m-semihosting/Cargo.toml b/cortex-m-semihosting/Cargo.toml
index 5afe0ac..ac0afa5 100644
--- a/cortex-m-semihosting/Cargo.toml
+++ b/cortex-m-semihosting/Cargo.toml
@@ -21,3 +21,4 @@ no-semihosting = []
 
 [dependencies]
 cortex-m = { path = "..", version = ">= 0.5.8, < 0.8" }
+critical-section = "1.0.0"
diff --git a/cortex-m-semihosting/src/export.rs b/cortex-m-semihosting/src/export.rs
index 0bbd09f..46e70e7 100644
--- a/cortex-m-semihosting/src/export.rs
+++ b/cortex-m-semihosting/src/export.rs
@@ -2,14 +2,12 @@
 
 use core::fmt::{self, Write};
 
-use cortex_m::interrupt;
-
 use crate::hio::{self, HostStream};
 
 static mut HSTDOUT: Option<HostStream> = None;
 
 pub fn hstdout_str(s: &str) {
-    let _result = interrupt::free(|_| unsafe {
+    let _result = critical_section::with(|_| unsafe {
         if HSTDOUT.is_none() {
             HSTDOUT = Some(hio::hstdout()?);
         }
@@ -19,7 +17,7 @@ pub fn hstdout_str(s: &str) {
 }
 
 pub fn hstdout_fmt(args: fmt::Arguments) {
-    let _result = interrupt::free(|_| unsafe {
+    let _result = critical_section::with(|_| unsafe {
         if HSTDOUT.is_none() {
             HSTDOUT = Some(hio::hstdout()?);
         }
@@ -31,7 +29,7 @@ pub fn hstdout_fmt(args: fmt::Arguments) {
 static mut HSTDERR: Option<HostStream> = None;
 
 pub fn hstderr_str(s: &str) {
-    let _result = interrupt::free(|_| unsafe {
+    let _result = critical_section::with(|_| unsafe {
         if HSTDERR.is_none() {
             HSTDERR = Some(hio::hstderr()?);
         }
@@ -41,7 +39,7 @@ pub fn hstderr_str(s: &str) {
 }
 
 pub fn hstderr_fmt(args: fmt::Arguments) {
-    let _result = interrupt::free(|_| unsafe {
+    let _result = critical_section::with(|_| unsafe {
         if HSTDERR.is_none() {
             HSTDERR = Some(hio::hstderr()?);
         }