Add CPI support for upgradeable loader (#14193)

programs/bpf/rust/invoke_and_return/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "solana-bpf-rust-invoke-and-return"
+version = "1.6.0"
+description = "Solana BPF test program written in Rust"
+authors = ["Solana Maintainers <maintainers@solana.foundation>"]
+repository = "https://github.com/solana-labs/solana"
+license = "Apache-2.0"
+homepage = "https://solana.com/"
+edition = "2018"
+
+[dependencies]
+solana-program = { path = "../../../../sdk/program", version = "1.6.0" }
+
+[lib]
+crate-type = ["cdylib"]
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]

programs/bpf/rust/invoke_and_return/Xargo.toml

@@ -0,0 +1,2 @@
+[target.bpfel-unknown-unknown.dependencies.std]
+features = []

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

@@ -0,0 +1,36 @@
+//! @brief Invokes an instruction and returns an error, the instruction invoked
+//! uses the instruction data provided and all the accounts
+
+use solana_program::{
+    account_info::AccountInfo, bpf_loader_upgradeable, entrypoint, entrypoint::ProgramResult,
+    instruction::AccountMeta, instruction::Instruction, program::invoke, pubkey::Pubkey,
+};
+
+entrypoint!(process_instruction);
+#[allow(clippy::unnecessary_wraps)]
+fn process_instruction(
+    _program_id: &Pubkey,
+    accounts: &[AccountInfo],
+    instruction_data: &[u8],
+) -> ProgramResult {
+    let to_call = accounts[0].key;
+    let infos = accounts;
+    let last = if bpf_loader_upgradeable::check_id(accounts[0].owner) {
+        accounts.len() - 1
+    } else {
+        accounts.len()
+    };
+    let instruction = Instruction {
+        accounts: accounts[1..last]
+            .iter()
+            .map(|acc| AccountMeta {
+                pubkey: *acc.key,
+                is_signer: acc.is_signer,
+                is_writable: acc.is_writable,
+            })
+            .collect(),
+        data: instruction_data.to_owned(),
+        program_id: *to_call,
+    };
+    invoke(&instruction, &infos)
+}