solana/sdk/src/entrypoint.rs
Justin Starry 81c36699c4
Add support for BPF program custom errors (#5743)
* Add support for BPF program custom errors

* Rename SOL_SUCCESS -> SUCCESS
2019-09-06 16:05:01 -07:00

118 lines
3.4 KiB
Rust

//! @brief Solana Rust-based BPF program entrypoint and its parameter types
extern crate alloc;
use crate::pubkey::Pubkey;
use alloc::vec::Vec;
use core::mem::size_of;
use core::slice::{from_raw_parts, from_raw_parts_mut};
/// Keyed Account
pub struct SolKeyedAccount<'a> {
/// Public key of the account
pub key: &'a Pubkey,
/// Public key of the account
pub is_signer: bool,
/// Number of lamports owned by this account
pub lamports: &'a mut u64,
/// On-chain data within this account
pub data: &'a mut [u8],
/// Program that owns this account
pub owner: &'a Pubkey,
}
/// User implemented program entrypoint
///
/// program_id: Program ID of the currently executing program
/// accounts: Accounts passed as part of the instruction
/// data: Instruction data
pub type ProcessInstruction =
fn(program_id: &Pubkey, accounts: &mut [SolKeyedAccount], data: &[u8]) -> bool;
/// Programs indicate success with a return value of 0
pub const SUCCESS: u32 = 0;
/// Declare entrypoint of the program.
///
/// Deserialize the program input parameters and call
/// the user defined `ProcessInstruction`. Users must call
/// this function otherwise an entrypoint for
/// their program will not be created.
#[macro_export]
macro_rules! entrypoint {
($process_instruction:ident) => {
#[no_mangle]
pub unsafe extern "C" fn entrypoint(input: *mut u8) -> u32 {
unsafe {
let (program_id, mut kas, data) = $crate::entrypoint::deserialize(input);
$process_instruction(&program_id, &mut kas, &data)
}
}
};
}
/// Deserialize the input parameters
#[allow(clippy::type_complexity)]
pub unsafe fn deserialize<'a>(
input: *mut u8,
) -> (&'a Pubkey, Vec<SolKeyedAccount<'a>>, &'a [u8]) {
let mut offset: usize = 0;
// Number of KeyedAccounts present
#[allow(clippy::cast_ptr_alignment)]
let num_ka = *(input.add(offset) as *const u64) as usize;
offset += size_of::<u64>();
// KeyedAccounts
let mut kas = Vec::with_capacity(num_ka);
for _ in 0..num_ka {
let is_signer = {
#[allow(clippy::cast_ptr_alignment)]
let is_signer_val = *(input.add(offset) as *const u64);
(is_signer_val != 0)
};
offset += size_of::<u64>();
let key: &Pubkey = &*(input.add(offset) as *const Pubkey);
offset += size_of::<Pubkey>();
#[allow(clippy::cast_ptr_alignment)]
let lamports = &mut *(input.add(offset) as *mut u64);
offset += size_of::<u64>();
#[allow(clippy::cast_ptr_alignment)]
let data_length = *(input.add(offset) as *const u64) as usize;
offset += size_of::<u64>();
let data = { from_raw_parts_mut(input.add(offset), data_length) };
offset += data_length;
let owner: &Pubkey = &*(input.add(offset) as *const Pubkey);
offset += size_of::<Pubkey>();
kas.push(SolKeyedAccount {
key,
is_signer,
lamports,
data,
owner,
});
}
// Instruction data
#[allow(clippy::cast_ptr_alignment)]
let data_length = *(input.add(offset) as *const u64) as usize;
offset += size_of::<u64>();
let data = { from_raw_parts(input.add(offset), data_length) };
offset += data_length;
// Program Id
let program_id: &Pubkey = &*(input.add(offset) as *const Pubkey);
(program_id, kas, data)
}