rcore-tutorial/user/src/bin/huge_write.rs

33 lines
793 B
Rust

#![no_std]
#![no_main]
#[macro_use]
extern crate user_lib;
use user_lib::{close, get_time, open, write, OpenFlags};
#[no_mangle]
pub fn main() -> i32 {
let mut buffer = [0u8; 1024]; // 1KiB
for (i, ch) in buffer.iter_mut().enumerate() {
*ch = i as u8;
}
let f = open("testf\0", OpenFlags::CREATE | OpenFlags::WRONLY);
if f < 0 {
panic!("Open test file failed!");
}
let f = f as usize;
let start = get_time();
let size_mb = 1usize;
for _ in 0..1024 * size_mb {
write(f, &buffer);
}
close(f);
let time_ms = (get_time() - start) as usize;
let speed_kbs = (size_mb << 20) / time_ms;
println!(
"{}MiB written, time cost = {}ms, write speed = {}KiB/s",
size_mb, time_ms, speed_kbs
);
0
}