run_emitter_test_suite/cstr/
mod.rs

1use std::{
2    fmt::{self, Display, Write as _},
3    slice, str,
4};
5
6#[allow(non_camel_case_types)]
7type c_char = i8;
8
9pub struct CStr {
10    ptr: *const u8,
11}
12
13impl CStr {
14    pub unsafe fn from_ptr(ptr: *const c_char) -> Self {
15        CStr {
16            ptr: ptr.cast(),
17        }
18    }
19}
20
21impl Display for CStr {
22    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
23        let len = unsafe { strlen(self.ptr) };
24        let mut bytes = unsafe { slice::from_raw_parts(self.ptr, len) };
25        loop {
26            match str::from_utf8(bytes) {
27                Ok(valid) => return formatter.write_str(valid),
28                Err(utf8_error) => {
29                    let valid_up_to = utf8_error.valid_up_to();
30                    let valid = unsafe { str::from_utf8_unchecked(&bytes[..valid_up_to]) };
31                    formatter.write_str(valid)?;
32                    formatter.write_char(char::REPLACEMENT_CHARACTER)?;
33                    if let Some(error_len) = utf8_error.error_len() {
34                        bytes = &bytes[valid_up_to + error_len..];
35                    } else {
36                        return Ok(());
37                    }
38                }
39            }
40        }
41    }
42}
43
44unsafe fn strlen(s: *const u8) -> usize {
45    let mut end = s;
46    while *end != 0 {
47        end = end.add(1);
48    }
49    end.offset_from(s) as usize
50}
run_emitter_test_suite/cstr/mod.rs

run_emitter_test_suite/cstr/
mod.rs
