Files
adler32
aho_corasick
alga
approx
ascii
atty
backtrace
backtrace_sys
base64
bitflags
blas_src
block_buffer
block_padding
brotli2
brotli_sys
buf_redux
byte_tools
byteorder
cauchy
cblas_sys
cfg_if
chrono
chunked_transfer
colored
crc32fast
crossbeam
crossbeam_channel
crossbeam_deque
crossbeam_epoch
crossbeam_queue
crossbeam_utils
ctrlc
deflate
digest
dirs
error_chain
filetime
futures
generic_array
getrandom
gzip_header
hex
httparse
hyper
idna
itoa
language_tags
lapack_src
lapacke
lapacke_sys
lazy_static
libc
libm
linked_hash_map
log
matches
matrixmultiply
maybe_uninit
md5
memchr
memoffset
mime
mime_guess
multipart
nalgebra
base
geometry
linalg
ndarray
ndarray_linalg
net2
netlib_src
nix
num_complex
num_cpus
num_integer
num_rational
num_traits
opaque_debug
percent_encoding
phf
phf_shared
ppv_lite86
proc_macro2
quick_error
quote
rand
rand_chacha
rand_core
rand_distr
rawpointer
regex
regex_syntax
remove_dir_all
rosrust
rosrust_codegen
rosrust_msg
rouille
rustc_demangle
rustros_tf
ryu
safemem
scopeguard
serde
serde_bytes
serde_derive
serde_json
serde_xml_rs
sha1
siphasher
smallvec
syn
tempdir
term
thread_local
threadpool
time
tiny_http
traitobject
twoway
typeable
typenum
ucd_util
unicase
unicode_bidi
unicode_normalization
unicode_xid
url
utf8_ranges
void
xml
xml_rpc
yaml_rust
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
use lib::*;

const TAG_CONT: u8 = 0b1000_0000;
const TAG_TWO_B: u8 = 0b1100_0000;
const TAG_THREE_B: u8 = 0b1110_0000;
const TAG_FOUR_B: u8 = 0b1111_0000;
const MAX_ONE_B: u32 = 0x80;
const MAX_TWO_B: u32 = 0x800;
const MAX_THREE_B: u32 = 0x10000;

#[inline]
pub fn encode(c: char) -> Encode {
    let code = c as u32;
    let mut buf = [0; 4];
    let pos = if code < MAX_ONE_B {
        buf[3] = code as u8;
        3
    } else if code < MAX_TWO_B {
        buf[2] = (code >> 6 & 0x1F) as u8 | TAG_TWO_B;
        buf[3] = (code & 0x3F) as u8 | TAG_CONT;
        2
    } else if code < MAX_THREE_B {
        buf[1] = (code >> 12 & 0x0F) as u8 | TAG_THREE_B;
        buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT;
        buf[3] = (code & 0x3F) as u8 | TAG_CONT;
        1
    } else {
        buf[0] = (code >> 18 & 0x07) as u8 | TAG_FOUR_B;
        buf[1] = (code >> 12 & 0x3F) as u8 | TAG_CONT;
        buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT;
        buf[3] = (code & 0x3F) as u8 | TAG_CONT;
        0
    };
    Encode { buf: buf, pos: pos }
}

pub struct Encode {
    buf: [u8; 4],
    pos: usize,
}

impl Encode {
    pub fn as_str(&self) -> &str {
        str::from_utf8(&self.buf[self.pos..]).unwrap()
    }
}