Make noop a real noop (#12196)

* Make noop a real noop

* nudge

programs/bpf/rust/sanity/src/lib.rs

@@ -0,0 +1,77 @@
+//! @brief Example Rust-based BPF sanity program that prints out the parameters passed to it
+
+#![allow(unreachable_code)]
+
+extern crate solana_sdk;
+use solana_sdk::{
+    account_info::AccountInfo, bpf_loader, entrypoint, entrypoint::ProgramResult, info, log::*,
+    pubkey::Pubkey,
+};
+
+#[derive(Debug, PartialEq)]
+struct SStruct {
+    x: u64,
+    y: u64,
+    z: u64,
+}
+
+#[inline(never)]
+fn return_sstruct() -> SStruct {
+    SStruct { x: 1, y: 2, z: 3 }
+}
+
+entrypoint!(process_instruction);
+fn process_instruction(
+    program_id: &Pubkey,
+    accounts: &[AccountInfo],
+    instruction_data: &[u8],
+) -> ProgramResult {
+    info!("Program identifier:");
+    program_id.log();
+
+    assert!(!bpf_loader::check_id(program_id));
+
+    // Log the provided account keys and instruction input data.  In the case of
+    // the no-op program, no account keys or input data are expected but real
+    // programs will have specific requirements so they can do their work.
+    info!("Account keys and instruction input data:");
+    sol_log_params(accounts, instruction_data);
+
+    {
+        // Test - use std methods, unwrap
+
+        // valid bytes, in a stack-allocated array
+        let sparkle_heart = [240, 159, 146, 150];
+        let result_str = std::str::from_utf8(&sparkle_heart).unwrap();
+        assert_eq!(4, result_str.len());
+        assert_eq!("💖", result_str);
+        info!(result_str);
+    }
+
+    {
+        // Test - struct return
+
+        let s = return_sstruct();
+        assert_eq!(s.x + s.y + s.z, 6);
+    }
+
+    {
+        // Test - arch config
+        #[cfg(not(target_arch = "bpf"))]
+        panic!();
+    }
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    // Pull in syscall stubs when building for non-BPF targets
+    solana_sdk::program_stubs!();
+
+    #[test]
+    fn test_return_sstruct() {
+        assert_eq!(SStruct { x: 1, y: 2, z: 3 }, return_sstruct());
+    }
+}