wasmer_wasix/syscalls/wasix/
getcwd.rs

1use super::*;
2use crate::syscalls::*;
3
4/// ### `getcwd()`
5/// Returns the current working directory
6/// If the path exceeds the size of the buffer then this function
7/// will return ERANGE
8#[instrument(level = "trace", skip_all, fields(path = field::Empty, max_path_len = field::Empty), ret)]
9pub fn getcwd<M: MemorySize>(
10    ctx: FunctionEnvMut<'_, WasiEnv>,
11    path: WasmPtr<u8, M>,
12    path_len: WasmPtr<M::Offset, M>,
13) -> Errno {
14    let env = ctx.data();
15    let (memory, mut state, inodes) = unsafe { env.get_memory_and_wasi_state_and_inodes(&ctx, 0) };
16
17    let max_path_len64: u64 = wasi_try_mem!(path_len.read(&memory)).into();
18    Span::current().record("max_path_len", max_path_len64);
19
20    let (_, cur_dir) = wasi_try!(state.fs.get_current_dir(inodes, crate::VIRTUAL_ROOT_FD));
21    Span::current().record("path", cur_dir.as_str());
22
23    let cur_dir_len = cur_dir.len();
24    wasi_try_mem!(path_len.write(&memory, wasi_try!(to_offset::<M>(cur_dir_len))));
25    if cur_dir_len as u64 > max_path_len64 {
26        return Errno::Range;
27    }
28
29    if path.is_null() || max_path_len64 == 0 {
30        return Errno::Inval;
31    }
32
33    let path_slice = wasi_try_mem!(path.slice(&memory, wasi_try!(to_offset::<M>(cur_dir_len))));
34    wasi_try_mem!(path_slice.write_slice(cur_dir.as_bytes()));
35    // null-terminate the path if it's shorter than max_path_len64
36    if (cur_dir_len as u64) < max_path_len64 {
37        let path_nul = wasi_try_mem!(path.add_offset(wasi_try!(to_offset::<M>(cur_dir_len))));
38        // null-terminate the path
39        wasi_try_mem!(path_nul.write(&memory, 0));
40    }
41    Errno::Success
42}
wasmer_wasix/syscalls/wasix/getcwd.rs

wasmer_wasix/syscalls/wasix/
getcwd.rs
