solana_define_syscall/
lib.rs

1pub mod definitions;
2
3#[cfg(target_feature = "static-syscalls")]
4#[macro_export]
5macro_rules! define_syscall {
6    (fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
7        #[inline]
8        pub unsafe fn $name($($arg: $typ),*) -> $ret {
9            // this enum is used to force the hash to be computed in a const context
10            #[repr(usize)]
11            enum Syscall {
12                Code = $crate::sys_hash(stringify!($name)),
13            }
14
15            let syscall: extern "C" fn($($arg: $typ),*) -> $ret = core::mem::transmute(Syscall::Code);
16            syscall($($arg),*)
17        }
18
19    };
20    (fn $name:ident($($arg:ident: $typ:ty),*)) => {
21        define_syscall!(fn $name($($arg: $typ),*) -> ());
22    }
23}
24
25#[cfg(not(target_feature = "static-syscalls"))]
26#[macro_export]
27macro_rules! define_syscall {
28    (fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
29        extern "C" {
30            pub fn $name($($arg: $typ),*) -> $ret;
31        }
32    };
33    (fn $name:ident($($arg:ident: $typ:ty),*)) => {
34        define_syscall!(fn $name($($arg: $typ),*) -> ());
35    }
36}
37
38#[cfg(target_feature = "static-syscalls")]
39pub const fn sys_hash(name: &str) -> usize {
40    murmur3_32(name.as_bytes(), 0) as usize
41}
42
43#[cfg(target_feature = "static-syscalls")]
44const fn murmur3_32(buf: &[u8], seed: u32) -> u32 {
45    const fn pre_mix(buf: [u8; 4]) -> u32 {
46        u32::from_le_bytes(buf)
47            .wrapping_mul(0xcc9e2d51)
48            .rotate_left(15)
49            .wrapping_mul(0x1b873593)
50    }
51
52    let mut hash = seed;
53
54    let mut i = 0;
55    while i < buf.len() / 4 {
56        let buf = [buf[i * 4], buf[i * 4 + 1], buf[i * 4 + 2], buf[i * 4 + 3]];
57        hash ^= pre_mix(buf);
58        hash = hash.rotate_left(13);
59        hash = hash.wrapping_mul(5).wrapping_add(0xe6546b64);
60
61        i += 1;
62    }
63
64    match buf.len() % 4 {
65        0 => {}
66        1 => {
67            hash = hash ^ pre_mix([buf[i * 4], 0, 0, 0]);
68        }
69        2 => {
70            hash = hash ^ pre_mix([buf[i * 4], buf[i * 4 + 1], 0, 0]);
71        }
72        3 => {
73            hash = hash ^ pre_mix([buf[i * 4], buf[i * 4 + 1], buf[i * 4 + 2], 0]);
74        }
75        _ => { /* unreachable!() */ }
76    }
77
78    hash = hash ^ buf.len() as u32;
79    hash = hash ^ (hash.wrapping_shr(16));
80    hash = hash.wrapping_mul(0x85ebca6b);
81    hash = hash ^ (hash.wrapping_shr(13));
82    hash = hash.wrapping_mul(0xc2b2ae35);
83    hash = hash ^ (hash.wrapping_shr(16));
84
85    hash
86}
solana_define_syscall/lib.rs

solana_define_syscall/
lib.rs
