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

*      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

           Copyright (c) 1997-2012 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 module contains a function for converting any UTF-16 character

strings to host byte order. */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

/* Generate code with 16 bit character support. */

#define COMPILE_PCRE16

#include "pcre_internal.h"

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

*  Convert any UTF-16 string to host byte order  *

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

/* This function takes an UTF-16 string and converts

it to host byte order. The length can be explicitly set,

or automatically detected for zero terminated strings.

BOMs can be kept or discarded during the conversion.

Conversion can be done in place (output == input).

Arguments:

  output     the output buffer, its size must be greater

             or equal than the input string

  input      any UTF-16 string

  length     the number of 16-bit units in the input string

             can be less than zero for zero terminated strings

  host_byte_order

             A non-zero value means the input is in host byte

             order, which can be dynamically changed by BOMs later.

             Initially it contains the starting byte order and returns

             with the last byte order so it can be used for stream

             processing. It can be NULL, which set the host byte

             order mode by default.

  keep_boms  for a non-zero value, the BOM (0xfeff) characters

             are copied as well

Returns:     the number of 16-bit units placed into the output buffer,

             including the zero-terminator

*/

int

pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *output, PCRE_SPTR16 input,

  int length, int *host_byte_order, int keep_boms)

{

#ifdef SUPPORT_UTF

/* This function converts any UTF-16 string to host byte order and optionally

removes any Byte Order Marks (BOMS). Returns with the remainig length. */

int host_bo = host_byte_order != NULL ? *host_byte_order : 1;

pcre_uchar *optr = (pcre_uchar *)output;

const pcre_uchar *iptr = (const pcre_uchar *)input;

const pcre_uchar *end;

/* The c variable must be unsigned. */

register pcre_uchar c;

if (length < 0)

  length = STRLEN_UC(iptr) + 1;

end = iptr + length;

while (iptr < end)

  {

  c = *iptr++;

  if (c == 0xfeff || c == 0xfffe)

    {

    /* Detecting the byte order of the machine is unnecessary, it is

    enough to know that the UTF-16 string has the same byte order or not. */

    host_bo = c == 0xfeff;

    if (keep_boms != 0)

      *optr++ = 0xfeff;

    else

      length--;

    }

  else

    *optr++ = host_bo ? c : ((c >> 8) | (c << 8)); /* Flip bytes if needed. */

  }

if (host_byte_order != NULL)

  *host_byte_order = host_bo;

#else /* Not SUPPORT_UTF */

(void)(output);  /* Keep picky compilers happy */

(void)(input);

(void)(keep_boms);

(void)(host_byte_order);

#endif /* SUPPORT_UTF */

return length;

}

/* End of pcre16_utf16_utils.c */