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31 lines
668 B
Rust
31 lines
668 B
Rust
use core::arch::asm;
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const SYSCALL_WRITE: usize = 64;
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const SYSCALL_EXIT: usize = 93;
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fn syscall(id: usize, args: [usize; 3]) -> isize {
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let mut ret: isize;
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unsafe {
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// a0寄存器同时作为输入参数和输出参数, {in_var} => {out_var}
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asm!(
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"ecall",
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inlateout("x10") args[0] => ret,
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in("x11") args[1],
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in("x12") args[2],
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in("x17") id
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);
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}
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ret
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}
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pub fn sys_write(fd: usize, buffer: &[u8]) -> isize {
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syscall(SYSCALL_WRITE, [fd, buffer.as_ptr() as usize, buffer.len()])
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}
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pub fn sys_exit(exit_code: i32) -> isize {
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syscall(SYSCALL_EXIT, [exit_code as usize, 0, 0])
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}
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