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    1: /*************************************************
    2: *      Perl-Compatible Regular Expressions       *
    3: *************************************************/
    4: 
    5: /* PCRE is a library of functions to support regular expressions whose syntax
    6: and semantics are as close as possible to those of the Perl 5 language.
    7: 
    8:                        Written by Philip Hazel
    9:            Copyright (c) 1997-2012 University of Cambridge
   10: 
   11: -----------------------------------------------------------------------------
   12: Redistribution and use in source and binary forms, with or without
   13: modification, are permitted provided that the following conditions are met:
   14: 
   15:     * Redistributions of source code must retain the above copyright notice,
   16:       this list of conditions and the following disclaimer.
   17: 
   18:     * Redistributions in binary form must reproduce the above copyright
   19:       notice, this list of conditions and the following disclaimer in the
   20:       documentation and/or other materials provided with the distribution.
   21: 
   22:     * Neither the name of the University of Cambridge nor the names of its
   23:       contributors may be used to endorse or promote products derived from
   24:       this software without specific prior written permission.
   25: 
   26: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   27: AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   28: IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   29: ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   30: LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   31: CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   32: SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   33: INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   34: CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   35: ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   36: POSSIBILITY OF SUCH DAMAGE.
   37: -----------------------------------------------------------------------------
   38: */
   39: 
   40: 
   41: /* This module contains a function for converting any UTF-32 character
   42: strings to host byte order. */
   43: 
   44: 
   45: #ifdef HAVE_CONFIG_H
   46: #include "config.h"
   47: #endif
   48: 
   49: /* Generate code with 32 bit character support. */
   50: #define COMPILE_PCRE32
   51: 
   52: #include "pcre_internal.h"
   53: 
   54: #ifdef SUPPORT_UTF
   55: static pcre_uint32
   56: swap_uint32(pcre_uint32 value)
   57: {
   58: return ((value & 0x000000ff) << 24) |
   59:        ((value & 0x0000ff00) <<  8) |
   60:        ((value & 0x00ff0000) >>  8) |
   61:        (value >> 24);
   62: }
   63: #endif
   64: 
   65: 
   66: /*************************************************
   67: *  Convert any UTF-32 string to host byte order  *
   68: *************************************************/
   69: 
   70: /* This function takes an UTF-32 string and converts
   71: it to host byte order. The length can be explicitly set,
   72: or automatically detected for zero terminated strings.
   73: BOMs can be kept or discarded during the conversion.
   74: Conversion can be done in place (output == input).
   75: 
   76: Arguments:
   77:   output     the output buffer, its size must be greater
   78:              or equal than the input string
   79:   input      any UTF-32 string
   80:   length     the number of 32-bit units in the input string
   81:              can be less than zero for zero terminated strings
   82:   host_byte_order
   83:              A non-zero value means the input is in host byte
   84:              order, which can be dynamically changed by BOMs later.
   85:              Initially it contains the starting byte order and returns
   86:              with the last byte order so it can be used for stream
   87:              processing. It can be NULL, which set the host byte
   88:              order mode by default.
   89:   keep_boms  for a non-zero value, the BOM (0xfeff) characters
   90:              are copied as well
   91: 
   92: Returns:     the number of 32-bit units placed into the output buffer,
   93:              including the zero-terminator
   94: */
   95: 
   96: int
   97: pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *output, PCRE_SPTR32 input,
   98:   int length, int *host_byte_order, int keep_boms)
   99: {
  100: #ifdef SUPPORT_UTF
  101: /* This function converts any UTF-32 string to host byte order and optionally
  102: removes any Byte Order Marks (BOMS). Returns with the remainig length. */
  103: int host_bo = host_byte_order != NULL ? *host_byte_order : 1;
  104: pcre_uchar *optr = (pcre_uchar *)output;
  105: const pcre_uchar *iptr = (const pcre_uchar *)input;
  106: const pcre_uchar *end;
  107: /* The c variable must be unsigned. */
  108: register pcre_uchar c;
  109: 
  110: if (length < 0)
  111:   end = iptr + STRLEN_UC(iptr) + 1;
  112: else
  113:   end = iptr + length;
  114: 
  115: while (iptr < end)
  116:   {
  117:   c = *iptr++;
  118:   if (c == 0x0000feffu || c == 0xfffe0000u)
  119:     {
  120:     /* Detecting the byte order of the machine is unnecessary, it is
  121:     enough to know that the UTF-32 string has the same byte order or not. */
  122:     host_bo = c == 0x0000feffu;
  123:     if (keep_boms != 0)
  124:       *optr++ = 0x0000feffu;
  125:     }
  126:   else
  127:     *optr++ = host_bo ? c : swap_uint32(c);
  128:   }
  129: if (host_byte_order != NULL)
  130:   *host_byte_order = host_bo;
  131: 
  132: #else /* SUPPORT_UTF */
  133: (void)(output);  /* Keep picky compilers happy */
  134: (void)(input);
  135: (void)(keep_boms);
  136: (void)(host_byte_order);
  137: #endif /* SUPPORT_UTF */
  138: return length;
  139: }
  140: 
  141: /* End of pcre32_utf32_utils.c */