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
swap_uint32(pcre_uint32 value)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
pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 * output,PCRE_SPTR32 input,int length,int * host_byte_order,int keep_boms)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 */
142