34 lines
636 B
Rust
34 lines
636 B
Rust
#[no_mangle]
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pub unsafe extern "C" fn memcpy(dest: *mut u8, src: *const u8, n: usize) -> *mut u8 {
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for i in 0..n {
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*dest.add(i) = *src.add(i);
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}
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dest
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}
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#[no_mangle]
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pub unsafe extern "C" fn memset(s: *mut u8, x: i32, n: usize) -> *mut u8 {
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for i in 0..n {
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*s.add(i) = x as u8;
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}
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s
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}
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#[no_mangle]
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pub unsafe extern "C" fn memcmp(s1: *mut u8, s2: *const u8, n: usize) -> i32 {
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for i in 0..n {
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let x = *s1.add(i);
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let y = *s2.add(i);
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if x == y {
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continue;
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}
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let (x, y) = (i32::from(x), i32::from(y));
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return x - y;
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}
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0
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}
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