909d7e57
 liuqimichale
build
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#include "sass.hpp"
#include <string>
#include <vector>
#include <cstdlib>
#include <cmath>
#include "utf8.h"
namespace Sass {
namespace UTF_8 {
using std::string;
// naming conventions:
// offset: raw byte offset (0 based)
// position: code point offset (0 based)
// index: code point offset (1 based or negative)
// function that will count the number of code points (utf-8 characters) from the given beginning to the given end
size_t code_point_count(const string& str, size_t start, size_t end) {
return utf8::distance(str.begin() + start, str.begin() + end);
}
size_t code_point_count(const string& str) {
return utf8::distance(str.begin(), str.end());
}
// function that will return the byte offset at a code point position
size_t offset_at_position(const string& str, size_t position) {
string::const_iterator it = str.begin();
utf8::advance(it, position, str.end());
return std::distance(str.begin(), it);
}
// function that returns number of bytes in a character at offset
size_t code_point_size_at_offset(const string& str, size_t offset) {
// get iterator from string and forward by offset
string::const_iterator stop = str.begin() + offset;
// check if beyond boundary
if (stop == str.end()) return 0;
// advance by one code point
utf8::advance(stop, 1, str.end());
// calculate offset for code point
return stop - str.begin() - offset;
}
// function that will return a normalized index, given a crazy one
size_t normalize_index(int index, size_t len) {
long signed_len = static_cast<long>(len);
// assuming the index is 1-based
// we are returning a 0-based index
if (index > 0 && index <= signed_len) {
// positive and within string length
return index-1;
}
else if (index > signed_len) {
// positive and past string length
return len;
}
else if (index == 0) {
return 0;
}
else if (std::abs((double)index) <= signed_len) {
// negative and within string length
return index + signed_len;
}
else {
// negative and past string length
return 0;
}
}
#ifdef _WIN32
// utf16 functions
using std::wstring;
// convert from utf16/wide string to utf8 string
string convert_from_utf16(const wstring& utf16)
{
string utf8;
// pre-allocate expected memory
utf8.reserve(sizeof(utf16)/2);
utf8::utf16to8(utf16.begin(), utf16.end(),
back_inserter(utf8));
return utf8;
}
// convert from utf8 string to utf16/wide string
wstring convert_to_utf16(const string& utf8)
{
wstring utf16;
// pre-allocate expected memory
utf16.reserve(code_point_count(utf8)*2);
utf8::utf8to16(utf8.begin(), utf8.end(),
back_inserter(utf16));
return utf16;
}
#endif
}
}
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