arch_program 0.6.4

A Rust library for building programs that run inside the Arch Virtual Machine. Provides core functionality for creating instructions, managing accounts, handling program errors, and interacting with the Arch runtime environment. Includes utilities for logging, transaction handling, and Bitcoin UTXO management.
Documentation 
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/// Rent Calculation
// pub const DEFAULT_LAMPORTS_PER_BYTE_YEAR: u64 = 1_000_000_000 / 100 * 365 / (1024 * 1024);
// TODO: Temp value as the rent is becoming greater than MIN_LAMPORTS_REQUIRED,
// fix that to a good value then comback to this
pub const DEFAULT_LAMPORTS_PER_BYTE_YEAR: u64 = 2;

/// Default amount of time (in years) the balance has to include rent for the
/// account to be rent exempt.
pub const DEFAULT_EXEMPTION_THRESHOLD: f64 = 2.0;

/// Account storage overhead for calculation of base rent.
///
/// This is the number of bytes required to store an account with no data. It is
/// added to an accounts data length when calculating [`Rent::minimum_balance`].
pub const ACCOUNT_STORAGE_OVERHEAD: u64 = 128;

/// Minimum balance due for rent-exemption of a given account data size.
pub fn minimum_rent(data_len: usize) -> u64 {
    let bytes = data_len as u64;
    (ACCOUNT_STORAGE_OVERHEAD + bytes) * DEFAULT_LAMPORTS_PER_BYTE_YEAR
}

/// Checks if the account is exempt from rent.
pub fn is_exempt(lamports: u64, data_len: usize) -> bool {
    let rent = minimum_rent(data_len);
    lamports >= rent
}