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core: Use appropriately sized integers for codepoints and bytes
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@Florob @alexcrichton
Florob authored and alexcrichton committed May 14, 2014
1 parent 74ad023 commit 2f71b72
Showing 1 changed file with 45 additions and 50 deletions.
95 changes: 45 additions & 50 deletions src/libcore/char.rs
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Expand Up @@ -33,13 +33,14 @@ use unicode::{derived_property, property, general_category, decompose, conversio
#[cfg(not(test))] use default::Default;

// UTF-8 ranges and tags for encoding characters
static TAG_CONT: uint = 128u;
static MAX_ONE_B: uint = 128u;
static TAG_TWO_B: uint = 192u;
static MAX_TWO_B: uint = 2048u;
static TAG_THREE_B: uint = 224u;
static MAX_THREE_B: uint = 65536u;
static TAG_FOUR_B: uint = 240u;
static TAG_CONT: u8 = 0b1000_0000u8;
static TAG_TWO_B: u8 = 0b1100_0000u8;
static TAG_THREE_B: u8 = 0b1110_0000u8;
static TAG_FOUR_B: u8 = 0b1111_0000u8;
static MAX_ONE_B: u32 = 0x80u32;
static MAX_TWO_B: u32 = 0x800u32;
static MAX_THREE_B: u32 = 0x10000u32;
static MAX_FOUR_B: u32 = 0x200000u32;

/*
Lu Uppercase_Letter an uppercase letter
Expand Down Expand Up @@ -285,37 +286,37 @@ pub fn from_digit(num: uint, radix: uint) -> Option<char> {
}

// Constants from Unicode 6.2.0 Section 3.12 Conjoining Jamo Behavior
static S_BASE: uint = 0xAC00;
static L_BASE: uint = 0x1100;
static V_BASE: uint = 0x1161;
static T_BASE: uint = 0x11A7;
static L_COUNT: uint = 19;
static V_COUNT: uint = 21;
static T_COUNT: uint = 28;
static N_COUNT: uint = (V_COUNT * T_COUNT);
static S_COUNT: uint = (L_COUNT * N_COUNT);
static S_BASE: u32 = 0xAC00;
static L_BASE: u32 = 0x1100;
static V_BASE: u32 = 0x1161;
static T_BASE: u32 = 0x11A7;
static L_COUNT: u32 = 19;
static V_COUNT: u32 = 21;
static T_COUNT: u32 = 28;
static N_COUNT: u32 = (V_COUNT * T_COUNT);
static S_COUNT: u32 = (L_COUNT * N_COUNT);

// Decompose a precomposed Hangul syllable
fn decompose_hangul(s: char, f: |char|) {
let si = s as uint - S_BASE;
let si = s as u32 - S_BASE;

let li = si / N_COUNT;
unsafe {
f(transmute((L_BASE + li) as u32));
f(transmute(L_BASE + li));

let vi = (si % N_COUNT) / T_COUNT;
f(transmute((V_BASE + vi) as u32));
f(transmute(V_BASE + vi));

let ti = si % T_COUNT;
if ti > 0 {
f(transmute((T_BASE + ti) as u32));
f(transmute(T_BASE + ti));
}
}
}

/// Returns the canonical decomposition of a character
pub fn decompose_canonical(c: char, f: |char|) {
if (c as uint) < S_BASE || (c as uint) >= (S_BASE + S_COUNT) {
if (c as u32) < S_BASE || (c as u32) >= (S_BASE + S_COUNT) {
decompose::canonical(c, f);
} else {
decompose_hangul(c, f);
Expand All @@ -324,7 +325,7 @@ pub fn decompose_canonical(c: char, f: |char|) {

/// Returns the compatibility decomposition of a character
pub fn decompose_compatible(c: char, f: |char|) {
if (c as uint) < S_BASE || (c as uint) >= (S_BASE + S_COUNT) {
if (c as u32) < S_BASE || (c as u32) >= (S_BASE + S_COUNT) {
decompose::compatibility(c, f);
} else {
decompose_hangul(c, f);
Expand Down Expand Up @@ -386,12 +387,7 @@ pub fn escape_default(c: char, f: |char|) {

/// Returns the amount of bytes this `char` would need if encoded in UTF-8
pub fn len_utf8_bytes(c: char) -> uint {
static MAX_ONE_B: uint = 128u;
static MAX_TWO_B: uint = 2048u;
static MAX_THREE_B: uint = 65536u;
static MAX_FOUR_B: uint = 2097152u;

let code = c as uint;
let code = c as u32;
match () {
_ if code < MAX_ONE_B => 1u,
_ if code < MAX_TWO_B => 2u,
Expand Down Expand Up @@ -606,41 +602,40 @@ impl Char for char {

fn len_utf8_bytes(&self) -> uint { len_utf8_bytes(*self) }

fn encode_utf8(&self, dst: &mut [u8]) -> uint {
let code = *self as uint;
fn encode_utf8<'a>(&self, dst: &'a mut [u8]) -> uint {
let code = *self as u32;
if code < MAX_ONE_B {
dst[0] = code as u8;
return 1;
1
} else if code < MAX_TWO_B {
dst[0] = (code >> 6u & 31u | TAG_TWO_B) as u8;
dst[1] = (code & 63u | TAG_CONT) as u8;
return 2;
dst[0] = (code >> 6u & 0x1F_u32) as u8 | TAG_TWO_B;
dst[1] = (code & 0x3F_u32) as u8 | TAG_CONT;
2
} else if code < MAX_THREE_B {
dst[0] = (code >> 12u & 15u | TAG_THREE_B) as u8;
dst[1] = (code >> 6u & 63u | TAG_CONT) as u8;
dst[2] = (code & 63u | TAG_CONT) as u8;
return 3;
dst[0] = (code >> 12u & 0x0F_u32) as u8 | TAG_THREE_B;
dst[1] = (code >> 6u & 0x3F_u32) as u8 | TAG_CONT;
dst[2] = (code & 0x3F_u32) as u8 | TAG_CONT;
3
} else {
dst[0] = (code >> 18u & 7u | TAG_FOUR_B) as u8;
dst[1] = (code >> 12u & 63u | TAG_CONT) as u8;
dst[2] = (code >> 6u & 63u | TAG_CONT) as u8;
dst[3] = (code & 63u | TAG_CONT) as u8;
return 4;
dst[0] = (code >> 18u & 0x07_u32) as u8 | TAG_FOUR_B;
dst[1] = (code >> 12u & 0x3F_u32) as u8 | TAG_CONT;
dst[2] = (code >> 6u & 0x3F_u32) as u8 | TAG_CONT;
dst[3] = (code & 0x3F_u32) as u8 | TAG_CONT;
4
}
}

fn encode_utf16(&self, dst: &mut [u16]) -> uint {
let mut ch = *self as uint;
if (ch & 0xFFFF_u) == ch {
// The BMP falls through (assuming non-surrogate, as it
// should)
assert!(ch <= 0xD7FF_u || ch >= 0xE000_u);
let mut ch = *self as u32;
if (ch & 0xFFFF_u32) == ch {
// The BMP falls through (assuming non-surrogate, as it should)
assert!(ch <= 0xD7FF_u32 || ch >= 0xE000_u32);
dst[0] = ch as u16;
1
} else {
// Supplementary planes break into surrogates.
assert!(ch >= 0x1_0000_u && ch <= 0x10_FFFF_u);
ch -= 0x1_0000_u;
assert!(ch >= 0x1_0000_u32 && ch <= 0x10_FFFF_u32);
ch -= 0x1_0000_u32;
dst[0] = 0xD800_u16 | ((ch >> 10) as u16);
dst[1] = 0xDC00_u16 | ((ch as u16) & 0x3FF_u16);
2
Expand Down

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