34 lines
966 B
Rust
34 lines
966 B
Rust
//! counter-auth is an example of a program *implementing* an external program
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//! interface. Here the `counter::Auth` trait, where we only allow a count
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//! to be incremented if it changes the counter from odd -> even or even -> odd.
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//! Creative, I know. :P.
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use anchor_lang::prelude::*;
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use counter::Auth;
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#[program]
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pub mod counter_auth {
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use super::*;
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#[state]
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pub struct CounterAuth;
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impl<'info> Auth<'info, Empty> for CounterAuth {
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fn is_authorized(_ctx: Context<Empty>, current: u64, new: u64) -> ProgramResult {
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if current % 2 == 0 {
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if new % 2 == 0 {
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return Err(ProgramError::Custom(50)); // Arbitrary error code.
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}
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} else {
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if new % 2 == 1 {
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return Err(ProgramError::Custom(60)); // Arbitrary error code.
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}
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}
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Ok(())
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}
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}
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}
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#[derive(Accounts)]
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pub struct Empty {}
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