xref: /aosp_15_r20/external/pcre/src/pcre2_ord2utf.c (revision 22dc650d8ae982c6770746019a6f94af92b0f024)

/*************************************************
*      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

-----------------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      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
      documentation and/or other materials provided with the distribution.

    * Neither the name of the University of Cambridge 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 COPYRIGHT OWNER OR CONTRIBUTORS 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.
-----------------------------------------------------------------------------
*/


/* 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. */


#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#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
int i, j;
for (i = 0; i < PRIV(utf8_table1_size); i++)
  if ((int)cvalue <= PRIV(utf8_table1)[i]) break;
buffer += i;
for (j = i; j > 0; j--)
 {
 *buffer-- = 0x80 | (cvalue & 0x3f);
 cvalue >>= 6;
 }
*buffer = PRIV(utf8_table2)[i] | 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 pcre_ord2utf.c */