solana/programs/sbf/rust/instruction_introspection/src/lib.rs

62 lines
1.9 KiB
Rust

//! Example Rust-based SBF program that exercises instruction introspection
extern crate solana_program;
use solana_program::{
account_info::AccountInfo,
entrypoint::ProgramResult,
instruction::{AccountMeta, Instruction},
msg,
program::invoke,
program_error::ProgramError,
pubkey::Pubkey,
sysvar::instructions,
};
solana_program::entrypoint!(process_instruction);
fn process_instruction(
program_id: &Pubkey,
accounts: &[AccountInfo],
instruction_data: &[u8],
) -> ProgramResult {
if instruction_data.is_empty() {
return Err(ProgramError::InvalidAccountData);
}
let secp_instruction_index = instruction_data[0];
let instructions_account = accounts.last().ok_or(ProgramError::NotEnoughAccountKeys)?;
assert_eq!(*instructions_account.key, instructions::id());
let data_len = instructions_account.try_borrow_data()?.len();
if data_len < 2 {
return Err(ProgramError::InvalidAccountData);
}
let instruction = instructions::load_instruction_at_checked(
secp_instruction_index as usize,
instructions_account,
)?;
let current_instruction = instructions::load_current_index_checked(instructions_account)?;
let my_index = instruction_data[1] as u16;
assert_eq!(current_instruction, my_index);
msg!(&format!("id: {}", instruction.program_id));
msg!(&format!("data[0]: {}", instruction.data[0]));
msg!(&format!("index: {current_instruction}"));
if instruction_data.len() == 2 {
// CPI ourself with the same arguments to confirm the instructions sysvar reports the same
// results from within a CPI
invoke(
&Instruction::new_with_bytes(
*program_id,
&[instruction_data[0], instruction_data[1], 1],
vec![AccountMeta::new_readonly(instructions::id(), false)],
),
&[instructions_account.clone()],
)?;
}
Ok(())
}