src/pcre2_ord2utf.c

/*************************************************
*      Perl-Compatible Regular Expressions       *
*************************************************/

/* PCRE is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language.

                       Written by Philip Hazel
     Original API code Copyright (c) 1997-2012 University of Cambridge
         New API code Copyright (c) 2016 University of Cambridge

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      this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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*/


/* This file contains a function that converts a Unicode character code point
into a UTF string. The behaviour is different for each code unit width. */


#include "pcre2_internal.h"



/* If SUPPORT_UNICODE is not defined, this function will never be called.
Supply a dummy function because some compilers do not like empty source
modules. */

#ifndef SUPPORT_UNICODE
unsigned int
PRIV(ord2utf)(uint32_t cvalue, PCRE2_UCHAR *buffer)
{
(void)(cvalue);
(void)(buffer);
return 0;
}
#else  /* SUPPORT_UNICODE */


/*************************************************
*          Convert code point to UTF             *
*************************************************/

/*
Arguments:
  cvalue     the character value
  buffer     pointer to buffer for result

Returns:     number of code units placed in the buffer
*/

unsigned int
PRIV(ord2utf)(uint32_t cvalue, PCRE2_UCHAR *buffer)
{
/* Convert to UTF-8 */

#if PCRE2_CODE_UNIT_WIDTH == 8
unsigned int i;

for (i = 0; i < PRIV(utf8_table1_size); i++)
  if ((int)cvalue <= PRIV(utf8_table1)[i]) break;
buffer += i;
for (unsigned int j = i; j != 0; j--)
 {
 *buffer-- = 0x80 | (cvalue & 0x3f);
 cvalue >>= 6;
 }
*buffer = (PCRE2_UCHAR)(PRIV(utf8_table2)[i] | (int)cvalue);
return i + 1;

/* Convert to UTF-16 */

#elif PCRE2_CODE_UNIT_WIDTH == 16
if (cvalue <= 0xffff)
  {
  *buffer = (PCRE2_UCHAR)cvalue;
  return 1;
  }
cvalue -= 0x10000;
*buffer++ = 0xd800 | (cvalue >> 10);
*buffer = 0xdc00 | (cvalue & 0x3ff);
return 2;

/* Convert to UTF-32 */

#else
*buffer = (PCRE2_UCHAR)cvalue;
return 1;
#endif
}
#endif  /* SUPPORT_UNICODE */

/* End of pcre2_ord2utf.c */