##// END OF EJS Templates
typing: add basic type hints to vfs.py...
typing: add basic type hints to vfs.py Again, there's a lot more that could be done, but this sticks to the obviously correct stuff that is related to primitives or `vfs` objects. Hopefully this helps smoke out more path related bytes vs str issues in TortoiseHg. PyCharm seems smart enough to apply hints from annotated superclass functions, but pytype isn't (according to the *.pyi file generated), so those are annotated too. There was some discussion about changing the default path arg from `None` to `b''` in order to avoid the more verbose `Optional` declarations. This would be more in line with `os.path.join()` (which rejects `None`, but ignores empty strings), and still not change the behavior for callers still passing `None` (because the check is `if path` instead of an explicit check for `None`). But I didn't want to hold this up while discussing that, so this documents what _is_.

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path_encode.rs
646 lines | 20.7 KiB | application/rls-services+xml | RustLexer
use sha1::{Digest, Sha1};
#[derive(PartialEq, Debug)]
#[allow(non_camel_case_types)]
enum path_state {
START, /* first byte of a path component */
A, /* "AUX" */
AU,
THIRD, /* third of a 3-byte sequence, e.g. "AUX", "NUL" */
C, /* "CON" or "COMn" */
CO,
COMLPT, /* "COM" or "LPT" */
COMLPTn,
L,
LP,
N,
NU,
P, /* "PRN" */
PR,
LDOT, /* leading '.' */
DOT, /* '.' in a non-leading position */
H, /* ".h" */
HGDI, /* ".hg", ".d", or ".i" */
SPACE,
DEFAULT, /* byte of a path component after the first */
}
/* state machine for dir-encoding */
#[allow(non_camel_case_types)]
enum dir_state {
DDOT,
DH,
DHGDI,
DDEFAULT,
}
fn inset(bitset: &[u32; 8], c: u8) -> bool {
bitset[(c as usize) >> 5] & (1 << (c & 31)) != 0
}
fn charcopy(dest: Option<&mut [u8]>, destlen: &mut usize, c: u8) {
if let Some(slice) = dest {
slice[*destlen] = c
}
*destlen += 1
}
fn memcopy(dest: Option<&mut [u8]>, destlen: &mut usize, src: &[u8]) {
if let Some(slice) = dest {
slice[*destlen..*destlen + src.len()].copy_from_slice(src)
}
*destlen += src.len();
}
fn rewrap_option<'a, 'b: 'a>(
x: &'a mut Option<&'b mut [u8]>,
) -> Option<&'a mut [u8]> {
match x {
None => None,
Some(y) => Some(y),
}
}
fn hexencode<'a>(mut dest: Option<&'a mut [u8]>, destlen: &mut usize, c: u8) {
let hexdigit = b"0123456789abcdef";
charcopy(
rewrap_option(&mut dest),
destlen,
hexdigit[(c as usize) >> 4],
);
charcopy(dest, destlen, hexdigit[(c as usize) & 15]);
}
/* 3-byte escape: tilde followed by two hex digits */
fn escape3(mut dest: Option<&mut [u8]>, destlen: &mut usize, c: u8) {
charcopy(rewrap_option(&mut dest), destlen, b'~');
hexencode(dest, destlen, c);
}
fn encode_dir(mut dest: Option<&mut [u8]>, src: &[u8]) -> usize {
let mut state = dir_state::DDEFAULT;
let mut i = 0;
let mut destlen = 0;
while i < src.len() {
match state {
dir_state::DDOT => match src[i] {
b'd' | b'i' => {
state = dir_state::DHGDI;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'h' => {
state = dir_state::DH;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
_ => {
state = dir_state::DDEFAULT;
}
},
dir_state::DH => {
if src[i] == b'g' {
state = dir_state::DHGDI;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = dir_state::DDEFAULT;
}
}
dir_state::DHGDI => {
if src[i] == b'/' {
memcopy(rewrap_option(&mut dest), &mut destlen, b".hg");
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
state = dir_state::DDEFAULT;
}
dir_state::DDEFAULT => {
if src[i] == b'.' {
state = dir_state::DDOT
}
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
}
}
destlen
}
fn _encode(
twobytes: &[u32; 8],
onebyte: &[u32; 8],
mut dest: Option<&mut [u8]>,
src: &[u8],
encodedir: bool,
) -> usize {
let mut state = path_state::START;
let mut i = 0;
let mut destlen = 0;
let len = src.len();
while i < len {
match state {
path_state::START => match src[i] {
b'/' => {
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'.' => {
state = path_state::LDOT;
escape3(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b' ' => {
state = path_state::DEFAULT;
escape3(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'a' => {
state = path_state::A;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'c' => {
state = path_state::C;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'l' => {
state = path_state::L;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'n' => {
state = path_state::N;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'p' => {
state = path_state::P;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
_ => {
state = path_state::DEFAULT;
}
},
path_state::A => {
if src[i] == b'u' {
state = path_state::AU;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::AU => {
if src[i] == b'x' {
state = path_state::THIRD;
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::THIRD => {
state = path_state::DEFAULT;
match src[i] {
b'.' | b'/' | b'\0' => escape3(
rewrap_option(&mut dest),
&mut destlen,
src[i - 1],
),
_ => i -= 1,
}
}
path_state::C => {
if src[i] == b'o' {
state = path_state::CO;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::CO => {
if src[i] == b'm' {
state = path_state::COMLPT;
i += 1;
} else if src[i] == b'n' {
state = path_state::THIRD;
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::COMLPT => {
if src[i] >= b'1' && src[i] <= b'9' {
state = path_state::COMLPTn;
i += 1;
} else {
state = path_state::DEFAULT;
charcopy(
rewrap_option(&mut dest),
&mut destlen,
src[i - 1],
);
}
}
path_state::COMLPTn => {
state = path_state::DEFAULT;
match src[i] {
b'.' | b'/' | b'\0' => {
escape3(
rewrap_option(&mut dest),
&mut destlen,
src[i - 2],
);
charcopy(
rewrap_option(&mut dest),
&mut destlen,
src[i - 1],
);
}
_ => {
memcopy(
rewrap_option(&mut dest),
&mut destlen,
&src[i - 2..i],
);
}
}
}
path_state::L => {
if src[i] == b'p' {
state = path_state::LP;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::LP => {
if src[i] == b't' {
state = path_state::COMLPT;
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::N => {
if src[i] == b'u' {
state = path_state::NU;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::NU => {
if src[i] == b'l' {
state = path_state::THIRD;
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::P => {
if src[i] == b'r' {
state = path_state::PR;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::PR => {
if src[i] == b'n' {
state = path_state::THIRD;
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::LDOT => match src[i] {
b'd' | b'i' => {
state = path_state::HGDI;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'h' => {
state = path_state::H;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
_ => {
state = path_state::DEFAULT;
}
},
path_state::DOT => match src[i] {
b'/' | b'\0' => {
state = path_state::START;
memcopy(rewrap_option(&mut dest), &mut destlen, b"~2e");
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'd' | b'i' => {
state = path_state::HGDI;
charcopy(rewrap_option(&mut dest), &mut destlen, b'.');
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
b'h' => {
state = path_state::H;
memcopy(rewrap_option(&mut dest), &mut destlen, b".h");
i += 1;
}
_ => {
state = path_state::DEFAULT;
charcopy(rewrap_option(&mut dest), &mut destlen, b'.');
}
},
path_state::H => {
if src[i] == b'g' {
state = path_state::HGDI;
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
} else {
state = path_state::DEFAULT;
}
}
path_state::HGDI => {
if src[i] == b'/' {
state = path_state::START;
if encodedir {
memcopy(
rewrap_option(&mut dest),
&mut destlen,
b".hg",
);
}
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1
} else {
state = path_state::DEFAULT;
}
}
path_state::SPACE => match src[i] {
b'/' | b'\0' => {
state = path_state::START;
memcopy(rewrap_option(&mut dest), &mut destlen, b"~20");
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
_ => {
state = path_state::DEFAULT;
charcopy(rewrap_option(&mut dest), &mut destlen, b' ');
}
},
path_state::DEFAULT => {
while i != len && inset(onebyte, src[i]) {
charcopy(rewrap_option(&mut dest), &mut destlen, src[i]);
i += 1;
}
if i == len {
break;
}
match src[i] {
b'.' => {
state = path_state::DOT;
i += 1
}
b' ' => {
state = path_state::SPACE;
i += 1
}
b'/' => {
state = path_state::START;
charcopy(rewrap_option(&mut dest), &mut destlen, b'/');
i += 1;
}
_ => {
if inset(onebyte, src[i]) {
loop {
charcopy(
rewrap_option(&mut dest),
&mut destlen,
src[i],
);
i += 1;
if !(i < len && inset(onebyte, src[i])) {
break;
}
}
} else if inset(twobytes, src[i]) {
let c = src[i];
i += 1;
charcopy(
rewrap_option(&mut dest),
&mut destlen,
b'_',
);
charcopy(
rewrap_option(&mut dest),
&mut destlen,
if c == b'_' { b'_' } else { c + 32 },
);
} else {
escape3(
rewrap_option(&mut dest),
&mut destlen,
src[i],
);
i += 1;
}
}
}
}
}
}
match state {
path_state::START => (),
path_state::A => (),
path_state::AU => (),
path_state::THIRD => {
escape3(rewrap_option(&mut dest), &mut destlen, src[i - 1])
}
path_state::C => (),
path_state::CO => (),
path_state::COMLPT => {
charcopy(rewrap_option(&mut dest), &mut destlen, src[i - 1])
}
path_state::COMLPTn => {
escape3(rewrap_option(&mut dest), &mut destlen, src[i - 2]);
charcopy(rewrap_option(&mut dest), &mut destlen, src[i - 1]);
}
path_state::L => (),
path_state::LP => (),
path_state::N => (),
path_state::NU => (),
path_state::P => (),
path_state::PR => (),
path_state::LDOT => (),
path_state::DOT => {
memcopy(rewrap_option(&mut dest), &mut destlen, b"~2e");
}
path_state::H => (),
path_state::HGDI => (),
path_state::SPACE => {
memcopy(rewrap_option(&mut dest), &mut destlen, b"~20");
}
path_state::DEFAULT => (),
};
destlen
}
fn basic_encode(dest: Option<&mut [u8]>, src: &[u8]) -> usize {
let twobytes: [u32; 8] = [0, 0, 0x87ff_fffe, 0, 0, 0, 0, 0];
let onebyte: [u32; 8] =
[1, 0x2bff_3bfa, 0x6800_0001, 0x2fff_ffff, 0, 0, 0, 0];
_encode(&twobytes, &onebyte, dest, src, true)
}
const MAXSTOREPATHLEN: usize = 120;
fn lower_encode(mut dest: Option<&mut [u8]>, src: &[u8]) -> usize {
let onebyte: [u32; 8] =
[1, 0x2bff_fbfb, 0xe800_0001, 0x2fff_ffff, 0, 0, 0, 0];
let lower: [u32; 8] = [0, 0, 0x07ff_fffe, 0, 0, 0, 0, 0];
let mut destlen = 0;
for c in src {
if inset(&onebyte, *c) {
charcopy(rewrap_option(&mut dest), &mut destlen, *c)
} else if inset(&lower, *c) {
charcopy(rewrap_option(&mut dest), &mut destlen, *c + 32)
} else {
escape3(rewrap_option(&mut dest), &mut destlen, *c)
}
}
destlen
}
fn aux_encode(dest: Option<&mut [u8]>, src: &[u8]) -> usize {
let twobytes = [0; 8];
let onebyte: [u32; 8] = [!0, 0xffff_3ffe, !0, !0, !0, !0, !0, !0];
_encode(&twobytes, &onebyte, dest, src, false)
}
fn hash_mangle(src: &[u8], sha: &[u8]) -> Vec<u8> {
let dirprefixlen = 8;
let maxshortdirslen = 68;
let mut destlen = 0;
let last_slash = src.iter().rposition(|b| *b == b'/');
let last_dot: Option<usize> = {
let s = last_slash.unwrap_or(0);
src[s..]
.iter()
.rposition(|b| *b == b'.')
.and_then(|i| Some(i + s))
};
let mut dest = vec![0; MAXSTOREPATHLEN];
memcopy(Some(&mut dest), &mut destlen, b"dh/");
{
let mut first = true;
for slice in src[..last_slash.unwrap_or_else(|| src.len())]
.split(|b| *b == b'/')
{
let slice = &slice[..std::cmp::min(slice.len(), dirprefixlen)];
if destlen + (slice.len() + if first { 0 } else { 1 })
> maxshortdirslen + 3
{
break;
} else {
if !first {
charcopy(Some(&mut dest), &mut destlen, b'/')
};
memcopy(Some(&mut dest), &mut destlen, slice);
if dest[destlen - 1] == b'.' || dest[destlen - 1] == b' ' {
dest[destlen - 1] = b'_'
}
}
first = false;
}
if !first {
charcopy(Some(&mut dest), &mut destlen, b'/');
}
}
let used = destlen + 40 + {
if let Some(l) = last_dot {
src.len() - l
} else {
0
}
};
if MAXSTOREPATHLEN > used {
let slop = MAXSTOREPATHLEN - used;
let basenamelen = match last_slash {
Some(l) => src.len() - l - 1,
None => src.len(),
};
let basenamelen = std::cmp::min(basenamelen, slop);
if basenamelen > 0 {
let start = match last_slash {
Some(l) => l + 1,
None => 0,
};
memcopy(
Some(&mut dest),
&mut destlen,
&src[start..][..basenamelen],
)
}
}
for c in sha {
hexencode(Some(&mut dest), &mut destlen, *c);
}
if let Some(l) = last_dot {
memcopy(Some(&mut dest), &mut destlen, &src[l..]);
}
if destlen == dest.len() {
dest
} else {
// sometimes the path are shorter than MAXSTOREPATHLEN
dest[..destlen].to_vec()
}
}
const MAXENCODE: usize = 4096 * 4;
fn hash_encode(src: &[u8]) -> Vec<u8> {
let dired = &mut [0; MAXENCODE];
let lowered = &mut [0; MAXENCODE];
let auxed = &mut [0; MAXENCODE];
let baselen = (src.len() - 5) * 3;
if baselen >= MAXENCODE {
panic!("path_encode::hash_encore: string too long: {}", baselen)
};
let dirlen = encode_dir(Some(&mut dired[..]), src);
let sha = Sha1::digest(&dired[..dirlen]);
let lowerlen = lower_encode(Some(&mut lowered[..]), &dired[..dirlen][5..]);
let auxlen = aux_encode(Some(&mut auxed[..]), &lowered[..lowerlen]);
hash_mangle(&auxed[..auxlen], &sha)
}
pub fn path_encode(path: &[u8]) -> Vec<u8> {
let newlen = if path.len() <= MAXSTOREPATHLEN {
basic_encode(None, path)
} else {
MAXSTOREPATHLEN + 1
};
if newlen <= MAXSTOREPATHLEN {
if newlen == path.len() {
path.to_vec()
} else {
let mut res = vec![0; newlen];
basic_encode(Some(&mut res), path);
res
}
} else {
hash_encode(&path)
}
}