Code shared from the Rust Playground

playground.rs

#![allow(dead_code, mutable_transmutes, non_camel_case_types, non_snake_case, non_upper_case_globals, unused_assignments, unused_mut)]
#![register_tool(c2rust)]
#![feature(register_tool)]
extern "C" {
    static mut stdin: *mut _IO_FILE;
    static mut stdout: *mut _IO_FILE;
    fn fflush(__stream: *mut FILE) -> libc::c_int;
    fn fread(
        __ptr: *mut libc::c_void,
        __size: size_t,
        __n: size_t,
        __stream: *mut FILE,
    ) -> size_t;
    fn fwrite(
        __ptr: *const libc::c_void,
        __size: size_t,
        __n: size_t,
        __s: *mut FILE,
    ) -> size_t;
    fn calloc(_: libc::c_ulong, _: libc::c_ulong) -> *mut libc::c_void;
    fn free(__ptr: *mut libc::c_void);
    fn strlen(_: *const libc::c_char) -> libc::c_ulong;
}
pub type uint8_t = libc::c_uchar;
pub type uint32_t = libc::c_uint;
pub type size_t = libc::c_ulong;
pub type __off_t = libc::c_long;
pub type __off64_t = libc::c_long;
#[derive(Copy, Clone)]
#[repr(C)]
pub struct _IO_FILE {
    pub _flags: libc::c_int,
    pub _IO_read_ptr: *mut libc::c_char,
    pub _IO_read_end: *mut libc::c_char,
    pub _IO_read_base: *mut libc::c_char,
    pub _IO_write_base: *mut libc::c_char,
    pub _IO_write_ptr: *mut libc::c_char,
    pub _IO_write_end: *mut libc::c_char,
    pub _IO_buf_base: *mut libc::c_char,
    pub _IO_buf_end: *mut libc::c_char,
    pub _IO_save_base: *mut libc::c_char,
    pub _IO_backup_base: *mut libc::c_char,
    pub _IO_save_end: *mut libc::c_char,
    pub _markers: *mut _IO_marker,
    pub _chain: *mut _IO_FILE,
    pub _fileno: libc::c_int,
    pub _flags2: libc::c_int,
    pub _old_offset: __off_t,
    pub _cur_column: libc::c_ushort,
    pub _vtable_offset: libc::c_schar,
    pub _shortbuf: [libc::c_char; 1],
    pub _lock: *mut libc::c_void,
    pub _offset: __off64_t,
    pub __pad1: *mut libc::c_void,
    pub __pad2: *mut libc::c_void,
    pub __pad3: *mut libc::c_void,
    pub __pad4: *mut libc::c_void,
    pub __pad5: size_t,
    pub _mode: libc::c_int,
    pub _unused2: [libc::c_char; 20],
}
pub type _IO_lock_t = ();
#[derive(Copy, Clone)]
#[repr(C)]
pub struct _IO_marker {
    pub _next: *mut _IO_marker,
    pub _sbuf: *mut _IO_FILE,
    pub _pos: libc::c_int,
}
pub type FILE = _IO_FILE;
#[no_mangle]
pub unsafe extern "C" fn getMessage(mut inputLength: *mut size_t) -> *mut uint8_t {
    let mut messageLength: uint32_t = 0 as libc::c_int as uint32_t;
    let mut result: size_t = fread(
        &mut messageLength as *mut uint32_t as *mut libc::c_void,
        ::std::mem::size_of::<uint32_t>() as libc::c_ulong,
        1 as libc::c_int as size_t,
        stdin,
    );
    let mut message: *mut uint8_t = calloc(
        messageLength.wrapping_add(1 as libc::c_int as libc::c_uint) as libc::c_ulong,
        ::std::mem::size_of::<uint8_t>() as libc::c_ulong,
    ) as *mut uint8_t;
    result = fread(
        message as *mut libc::c_void,
        ::std::mem::size_of::<uint8_t>() as libc::c_ulong,
        messageLength as size_t,
        stdin,
    );
    *inputLength = messageLength as size_t;
    return message;
}
#[no_mangle]
pub unsafe extern "C" fn sendMessage(mut response: *mut uint8_t) {
    let responseLength: uint32_t = strlen(response as *const libc::c_char) as uint32_t;
    fwrite(
        &responseLength as *const uint32_t as *const libc::c_void,
        ::std::mem::size_of::<uint32_t>() as libc::c_ulong,
        1 as libc::c_int as size_t,
        stdout,
    );
    fwrite(
        response as *const libc::c_void,
        responseLength as size_t,
        1 as libc::c_int as size_t,
        stdout,
    );
    fflush(stdout);
}
unsafe fn main_0() -> libc::c_int {
    loop {
        let mut messageLength: size_t = 0 as libc::c_int as size_t;
        let message: *mut uint8_t = getMessage(&mut messageLength);
        sendMessage(message);
        free(message as *mut libc::c_void);
    };
}
pub fn main() {
    unsafe { ::std::process::exit(main_0() as i32) }
}