xref: /aosp_15_r20/external/flashrom/util/flashrom_tester/src/rand_util.rs (revision 0d6140be3aa665ecc836e8907834fcd3e3b018fc)
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35 
36 use std::fs::File;
37 use std::io::prelude::*;
38 use std::io::BufWriter;
39 use std::path::Path;
40 
41 use rand::prelude::*;
42 
gen_rand_testdata(path: &Path, size: usize) -> std::io::Result<()>43 pub fn gen_rand_testdata(path: &Path, size: usize) -> std::io::Result<()> {
44     let mut buf = BufWriter::new(File::create(path)?);
45 
46     let mut a: Vec<u8> = vec![0; size];
47     thread_rng().fill(a.as_mut_slice());
48 
49     buf.write_all(a.as_slice())?;
50 
51     Ok(())
52 }
53 
54 #[cfg(test)]
55 mod tests {
56     use super::*;
57 
58     #[test]
gen_rand_testdata()59     fn gen_rand_testdata() {
60         use super::gen_rand_testdata;
61 
62         let path0 = Path::new("/tmp/idk_test00");
63         let path1 = Path::new("/tmp/idk_test01");
64         let sz = 1024;
65 
66         gen_rand_testdata(path0, sz).unwrap();
67         gen_rand_testdata(path1, sz).unwrap();
68 
69         let mut buf0 = Vec::new();
70         let mut buf1 = Vec::new();
71 
72         let mut f = File::open(path0).unwrap();
73         let mut g = File::open(path1).unwrap();
74 
75         f.read_to_end(&mut buf0).unwrap();
76         g.read_to_end(&mut buf1).unwrap();
77 
78         assert_ne!(buf0, buf1);
79     }
80 }
81