tor-android/external/badvpn_dns/misc/Utf16Encoder.h

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2015-01-25 11:08:34 +00:00
/**
* @file Utf16Encoder.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef BADVPN_UTF16ENCODER_H
#define BADVPN_UTF16ENCODER_H
#include <stdint.h>
/**
* Encodes a Unicode character into a sequence of 16-bit values according to UTF-16.
*
* @param ch Unicode character to encode
* @param out will receive the encoded 16-bit values. Must have space for 2 values.
* @return number of 16-bit values written, 0-2, with 0 meaning the character cannot
* be encoded
*/
static int Utf16Encoder_EncodeCharacter (uint32_t ch, uint16_t *out);
int Utf16Encoder_EncodeCharacter (uint32_t ch, uint16_t *out)
{
if (ch <= UINT32_C(0xFFFF)) {
// surrogates
if (ch >= UINT32_C(0xD800) && ch <= UINT32_C(0xDFFF)) {
return 0;
}
out[0] = ch;
return 1;
}
if (ch <= UINT32_C(0x10FFFF)) {
uint32_t x = ch - UINT32_C(0x10000);
out[0] = UINT32_C(0xD800) + (x >> 10);
out[1] = UINT32_C(0xDC00) + (x & UINT32_C(0x3FF));
return 2;
}
return 0;
}
#endif