From d0fe654c82b548d65f49213ad50fc2edc5b3d71e Mon Sep 17 00:00:00 2001
From: Ulf Lilleengen <ulf.lilleengen@gmail.com>
Date: Tue, 20 Sep 2022 09:42:40 +0200
Subject: [PATCH] Remove BootFlash borrow

Compiler will infer a different lifetime for BootFlash than for the
borrowed flash, which makes it require more type annotations than if it
was just owning the type. Since it doesn't really matter if it owns or
borrows in practical use, change it to own so that it simplifies usage.
---
 embassy-boot/boot/src/lib.rs               | 24 +++++++++++-----------
 examples/boot/bootloader/nrf/src/main.rs   |  2 +-
 examples/boot/bootloader/stm32/src/main.rs |  7 +++----
 3 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/embassy-boot/boot/src/lib.rs b/embassy-boot/boot/src/lib.rs
index 4a2b112a..015dd58d 100644
--- a/embassy-boot/boot/src/lib.rs
+++ b/embassy-boot/boot/src/lib.rs
@@ -447,24 +447,24 @@ where
 }
 
 /// A flash wrapper implementing the Flash and embedded_storage traits.
-pub struct BootFlash<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8 = 0xFF>
+pub struct BootFlash<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8 = 0xFF>
 where
     F: NorFlash + ReadNorFlash,
 {
-    flash: &'a mut F,
+    flash: F,
 }
 
-impl<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> BootFlash<'a, F, BLOCK_SIZE, ERASE_VALUE>
+impl<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> BootFlash<F, BLOCK_SIZE, ERASE_VALUE>
 where
     F: NorFlash + ReadNorFlash,
 {
     /// Create a new instance of a bootable flash
-    pub fn new(flash: &'a mut F) -> Self {
+    pub fn new(flash: F) -> Self {
         Self { flash }
     }
 }
 
-impl<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> Flash for BootFlash<'a, F, BLOCK_SIZE, ERASE_VALUE>
+impl<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> Flash for BootFlash<F, BLOCK_SIZE, ERASE_VALUE>
 where
     F: NorFlash + ReadNorFlash,
 {
@@ -472,14 +472,14 @@ where
     const ERASE_VALUE: u8 = ERASE_VALUE;
 }
 
-impl<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> ErrorType for BootFlash<'a, F, BLOCK_SIZE, ERASE_VALUE>
+impl<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> ErrorType for BootFlash<F, BLOCK_SIZE, ERASE_VALUE>
 where
     F: ReadNorFlash + NorFlash,
 {
     type Error = F::Error;
 }
 
-impl<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> NorFlash for BootFlash<'a, F, BLOCK_SIZE, ERASE_VALUE>
+impl<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> NorFlash for BootFlash<F, BLOCK_SIZE, ERASE_VALUE>
 where
     F: ReadNorFlash + NorFlash,
 {
@@ -487,26 +487,26 @@ where
     const ERASE_SIZE: usize = F::ERASE_SIZE;
 
     fn erase(&mut self, from: u32, to: u32) -> Result<(), Self::Error> {
-        F::erase(self.flash, from, to)
+        F::erase(&mut self.flash, from, to)
     }
 
     fn write(&mut self, offset: u32, bytes: &[u8]) -> Result<(), Self::Error> {
-        F::write(self.flash, offset, bytes)
+        F::write(&mut self.flash, offset, bytes)
     }
 }
 
-impl<'a, F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> ReadNorFlash for BootFlash<'a, F, BLOCK_SIZE, ERASE_VALUE>
+impl<F, const BLOCK_SIZE: usize, const ERASE_VALUE: u8> ReadNorFlash for BootFlash<F, BLOCK_SIZE, ERASE_VALUE>
 where
     F: ReadNorFlash + NorFlash,
 {
     const READ_SIZE: usize = F::READ_SIZE;
 
     fn read(&mut self, offset: u32, bytes: &mut [u8]) -> Result<(), Self::Error> {
-        F::read(self.flash, offset, bytes)
+        F::read(&mut self.flash, offset, bytes)
     }
 
     fn capacity(&self) -> usize {
-        F::capacity(self.flash)
+        F::capacity(&self.flash)
     }
 }
 
diff --git a/examples/boot/bootloader/nrf/src/main.rs b/examples/boot/bootloader/nrf/src/main.rs
index 9031997c..8266206b 100644
--- a/examples/boot/bootloader/nrf/src/main.rs
+++ b/examples/boot/bootloader/nrf/src/main.rs
@@ -21,7 +21,7 @@ fn main() -> ! {
 
     let mut bl = BootLoader::default();
     let start = bl.prepare(&mut SingleFlashConfig::new(&mut BootFlash::<_, 4096>::new(
-        &mut WatchdogFlash::start(Nvmc::new(p.NVMC), p.WDT, 5),
+        WatchdogFlash::start(Nvmc::new(p.NVMC), p.WDT, 5),
     )));
     unsafe { bl.load(start) }
 }
diff --git a/examples/boot/bootloader/stm32/src/main.rs b/examples/boot/bootloader/stm32/src/main.rs
index bb5d3e53..294464d1 100644
--- a/examples/boot/bootloader/stm32/src/main.rs
+++ b/examples/boot/bootloader/stm32/src/main.rs
@@ -20,10 +20,9 @@ fn main() -> ! {
     */
 
     let mut bl: BootLoader<ERASE_SIZE, WRITE_SIZE> = BootLoader::default();
-    let mut flash = Flash::unlock(p.FLASH);
-    let start = bl.prepare(&mut SingleFlashConfig::new(
-        &mut BootFlash::<_, ERASE_SIZE, ERASE_VALUE>::new(&mut flash),
-    ));
+    let flash = Flash::unlock(p.FLASH);
+    let mut flash = BootFlash::<_, ERASE_SIZE, ERASE_VALUE>::new(flash);
+    let start = bl.prepare(&mut SingleFlashConfig::new(&mut flash));
     core::mem::drop(flash);
     unsafe { bl.load(start) }
 }