solana_sysvar_id/
lib.rs

1//! Access to special accounts with dynamically-updated data.
2//!
3//! Sysvars are special accounts that contain dynamically-updated data about the
4//! network cluster, the blockchain history, and the executing transaction. Each
5//! sysvar is defined in its own crate. The [`clock`], [`epoch_schedule`],
6//! [`instructions`], and [`rent`] sysvars are most useful to on-chain programs.
7//!
8//! [`clock`]: https://docs.rs/solana-clock/latest
9//! [`epoch_schedule`]: https://docs.rs/solana-epoch-schedule/latest
10//! [`instructions`]: https://docs.rs/solana-program/latest/solana_program/sysvar/instructions
11//! [`rent`]: https://docs.rs/solana-rent/latest
12//!
13//! All sysvar accounts are owned by the account identified by [`solana_sysvar::ID`].
14//!
15//! [`solana_sysvar::ID`]: crate::ID
16//!
17//! For more details see the Solana [documentation on sysvars][sysvardoc].
18//!
19//! [sysvardoc]: https://docs.solanalabs.com/runtime/sysvars
20
21/// Re-export types required for macros
22pub use solana_pubkey::{declare_deprecated_id, declare_id, Pubkey};
23
24/// A type that holds sysvar data and has an associated sysvar `Pubkey`.
25pub trait SysvarId {
26    /// The `Pubkey` of the sysvar.
27    fn id() -> Pubkey;
28
29    /// Returns `true` if the given pubkey is the program ID.
30    fn check_id(pubkey: &Pubkey) -> bool;
31}
32
33/// Declares an ID that implements [`SysvarId`].
34#[macro_export]
35macro_rules! declare_sysvar_id(
36    ($name:expr, $type:ty) => (
37        $crate::declare_id!($name);
38
39        impl $crate::SysvarId for $type {
40            fn id() -> $crate::Pubkey {
41                id()
42            }
43
44            fn check_id(pubkey: &$crate::Pubkey) -> bool {
45                check_id(pubkey)
46            }
47        }
48    )
49);
50
51/// Same as [`declare_sysvar_id`] except that it reports that this ID has been deprecated.
52#[macro_export]
53macro_rules! declare_deprecated_sysvar_id(
54    ($name:expr, $type:ty) => (
55        $crate::declare_deprecated_id!($name);
56
57        impl $crate::SysvarId for $type {
58            fn id() -> $crate::Pubkey {
59                #[allow(deprecated)]
60                id()
61            }
62
63            fn check_id(pubkey: &$crate::Pubkey) -> bool {
64                #[allow(deprecated)]
65                check_id(pubkey)
66            }
67        }
68    )
69);
70
71// Owner pubkey for sysvar accounts
72solana_pubkey::declare_id!("Sysvar1111111111111111111111111111111111111");
solana_sysvar_id/lib.rs

solana_sysvar_id/
lib.rs
