Fixes from PR

- Some comment fixes.
- Make some functions unsafe.
- Make helpers module private.
- Rebase on master
- Update r-efi to v4.2.0

Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>

Author: Ayush1325

std/Cargo.toml

@@ -49,7 +49,7 @@ hermit-abi = { version = "0.3.2", features = ['rustc-dep-of-std'], public = true
 wasi = { version = "0.11.0", features = ['rustc-dep-of-std'], default-features = false }
 
 [target.'cfg(target_os = "uefi")'.dependencies]
-r-efi = { version = "4.1.0", features = ['rustc-dep-of-std', 'efiapi']}
+r-efi = { version = "4.2.0", features = ['rustc-dep-of-std']}
 r-efi-alloc = { version = "1.0.0", features = ['rustc-dep-of-std']}
 
 [features]

std/src/os/uefi/env.rs

@@ -66,7 +66,7 @@ pub(crate) fn try_system_table() -> Option<NonNull<c_void>> {
 }
 
 /// Get the SystemHandle Pointer.
-/// This function is mostly intended for places where panic is not an option
+/// This function is mostly intended for places where panicking is not an option
 pub(crate) fn try_image_handle() -> Option<NonNull<c_void>> {
     GLOBALS.get().map(|x| x.1)
 }

std/src/sys/uefi/helpers.rs

@@ -295,7 +295,9 @@ pub(crate) fn create_event(
     }
 }
 
-pub(crate) fn close_event(evt: NonNull<crate::ffi::c_void>) -> io::Result<()> {
+/// # SAFETY
+/// - The supplied event must be valid
+pub(crate) unsafe fn close_event(evt: NonNull<crate::ffi::c_void>) -> io::Result<()> {
     let boot_services: NonNull<efi::BootServices> =
         boot_services().ok_or(BOOT_SERVICES_UNAVAILABLE)?.cast();
     let r = unsafe {

std/src/sys/uefi/mod.rs

@@ -47,7 +47,7 @@ pub mod thread_local_key;
 #[path = "../unsupported/time.rs"]
 pub mod time;
 
-pub(crate) mod helpers;
+mod helpers;
 
 #[cfg(test)]
 mod tests;
@@ -96,7 +96,7 @@ pub(crate) unsafe fn init(argc: isize, argv: *const *const u8, _sigpipe: u8) {
 /// - must be called only once during runtime cleanup.
 pub unsafe fn cleanup() {
     if let Some(exit_boot_service_event) = EXIT_BOOT_SERVICE_EVENT.take() {
-        let _ = helpers::close_event(exit_boot_service_event);
+        let _ = unsafe { helpers::close_event(exit_boot_service_event) };
     }
 }
 
@@ -123,7 +123,7 @@ pub fn decode_error_kind(code: i32) -> crate::io::ErrorKind {
 
 pub fn abort_internal() -> ! {
     if let Some(exit_boot_service_event) = EXIT_BOOT_SERVICE_EVENT.take() {
-        let _ = helpers::close_event(exit_boot_service_event);
+        let _ = unsafe { helpers::close_event(exit_boot_service_event) };
     }
 
     if let (Some(boot_services), Some(handle)) =