feat: middleware entrypoint

sdk/pinocchio/src/entrypoint/middleware.rs

@@ -0,0 +1,35 @@
+//! Defines the middleware entrypoint, enabling a hot path to bypass
+//! entrypoint deserialization, ejecting to the cold path on failure.
+#[macro_export]
+macro_rules! middleware_entrypoint {
+    ($hot:expr, $cold:expr) => {
+        $crate::middleware_entrypoint!($hot, $cold, { $crate::MAX_TX_ACCOUNTS });
+    };
+    ($hot:expr, $cold:expr, $maximum:expr ) => {
+
+        #[no_mangle]
+        pub unsafe extern "C" fn entrypoint(input: *mut u8) -> u64 {
+            if $hot(input) == 0 {
+                return $crate::SUCCESS
+            }
+
+            const UNINIT: core::mem::MaybeUninit<$crate::account_info::AccountInfo> = core::mem::MaybeUninit::<$crate::account_info::AccountInfo>::uninit();
+            // Create an array of uninitialized account infos.
+            let mut accounts = [UNINIT; $maximum];
+
+            let (program_id, count, instruction_data) = unsafe {
+                $crate::entrypoint::deserialize::<$maximum>(input, &mut accounts) }; 
+
+            // Call the program's entrypoint passing `count` account infos; we know that
+            // they are initialized so we cast the pointer to a slice of `[AccountInfo]`.
+            match $cold(
+                &program_id,
+                unsafe { core::slice::from_raw_parts(accounts.as_ptr() as _, count) },
+                &instruction_data,
+            ) {
+                Ok(()) => $crate::SUCCESS,
+                Err(error) => error.into(),
+            }
+        }
+    };
+}

sdk/pinocchio/src/entrypoint/mod.rs

@@ -5,6 +5,8 @@ pub mod lazy;
 
 pub use lazy::{InstructionContext, MaybeAccount};
 
+pub mod middleware;
+
 #[cfg(not(feature = "std"))]
 use core::alloc::{GlobalAlloc, Layout};