xref: /PHP-8.4/ext/pcre/pcre2lib/pcre2_ord2utf.c (revision a5bc5aed)
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      Original API code Copyright (c) 1997-2012 University of Cambridge
10          New API code Copyright (c) 2016 University of Cambridge
11 
12 -----------------------------------------------------------------------------
13 Redistribution and use in source and binary forms, with or without
14 modification, are permitted provided that the following conditions are met:
15 
16     * Redistributions of source code must retain the above copyright notice,
17       this list of conditions and the following disclaimer.
18 
19     * Redistributions in binary form must reproduce the above copyright
20       notice, this list of conditions and the following disclaimer in the
21       documentation and/or other materials provided with the distribution.
22 
23     * Neither the name of the University of Cambridge nor the names of its
24       contributors may be used to endorse or promote products derived from
25       this software without specific prior written permission.
26 
27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
28 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
31 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 POSSIBILITY OF SUCH DAMAGE.
38 -----------------------------------------------------------------------------
39 */
40 
41 
42 /* This file contains a function that converts a Unicode character code point
43 into a UTF string. The behaviour is different for each code unit width. */
44 
45 
46 #ifdef HAVE_CONFIG_H
47 #include "config.h"
48 #endif
49 
50 #include "pcre2_internal.h"
51 
52 
53 /* If SUPPORT_UNICODE is not defined, this function will never be called.
54 Supply a dummy function because some compilers do not like empty source
55 modules. */
56 
57 #ifndef SUPPORT_UNICODE
58 unsigned int
PRIV(ord2utf)59 PRIV(ord2utf)(uint32_t cvalue, PCRE2_UCHAR *buffer)
60 {
61 (void)(cvalue);
62 (void)(buffer);
63 return 0;
64 }
65 #else  /* SUPPORT_UNICODE */
66 
67 
68 /*************************************************
69 *          Convert code point to UTF             *
70 *************************************************/
71 
72 /*
73 Arguments:
74   cvalue     the character value
75   buffer     pointer to buffer for result
76 
77 Returns:     number of code units placed in the buffer
78 */
79 
80 unsigned int
PRIV(ord2utf)81 PRIV(ord2utf)(uint32_t cvalue, PCRE2_UCHAR *buffer)
82 {
83 /* Convert to UTF-8 */
84 
85 #if PCRE2_CODE_UNIT_WIDTH == 8
86 int i, j;
87 for (i = 0; i < PRIV(utf8_table1_size); i++)
88   if ((int)cvalue <= PRIV(utf8_table1)[i]) break;
89 buffer += i;
90 for (j = i; j > 0; j--)
91  {
92  *buffer-- = 0x80 | (cvalue & 0x3f);
93  cvalue >>= 6;
94  }
95 *buffer = PRIV(utf8_table2)[i] | cvalue;
96 return i + 1;
97 
98 /* Convert to UTF-16 */
99 
100 #elif PCRE2_CODE_UNIT_WIDTH == 16
101 if (cvalue <= 0xffff)
102   {
103   *buffer = (PCRE2_UCHAR)cvalue;
104   return 1;
105   }
106 cvalue -= 0x10000;
107 *buffer++ = 0xd800 | (cvalue >> 10);
108 *buffer = 0xdc00 | (cvalue & 0x3ff);
109 return 2;
110 
111 /* Convert to UTF-32 */
112 
113 #else
114 *buffer = (PCRE2_UCHAR)cvalue;
115 return 1;
116 #endif
117 }
118 #endif  /* SUPPORT_UNICODE */
119 
120 /* End of pcre_ord2utf.c */
121