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#include "encode_utf16.h"
namespace simdutf {
namespace tests {
namespace reference {
namespace utf16 {
// returns whether the value can be represented in the UTF-16
bool valid_value(uint32_t value) {
/*
RFC-2781 (2. UTF-16 definition):
Characters with values greater than 0x10FFFF cannot be encoded in UTF-16.
*/
if (value > 0x10FFFF)
return false;
/*
RFC-2781 (2. UTF-16 definition):
Note: Values between 0xD800 and 0xDFFF are specifically reserved for
use with UTF-16, and don't have any characters assigned to them.
*/
if ((value >= 0xD800) && (value <= 0xDFFF))
return false;
return true;
}
// Encodes the value using either one or two code units (returns 1 or 2
// respectively) Returns 0 if the value cannot be encoded
int encode(uint32_t value, char16_t &W1, char16_t &W2) {
if (!valid_value(value))
return 0;
if (value <= 0xffff) {
W1 = char16_t(value);
return 1;
} else {
value -= 0x10000;
W1 = char16_t(0xd800 | ((value >> 10) & 0x03ff));
W2 = char16_t(0xdc00 | (value & 0x03ff));
return 2;
}
}
} // namespace utf16
} // namespace reference
} // namespace tests
} // namespace simdutf
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