1 | /* This is JavaScriptCore's variant of the PCRE library. While this library |
2 | started out as a copy of PCRE, many of the features of PCRE have been |
3 | removed. This library now supports only the regular expression features |
4 | required by the JavaScript language specification, and has only the functions |
5 | needed by JavaScriptCore and the rest of WebKit. |
6 | |
7 | Originally written by Philip Hazel |
8 | Copyright (c) 1997-2006 University of Cambridge |
9 | Copyright (C) 2002, 2004, 2006, 2007 Apple Inc. All rights reserved. |
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 | * Unicode Property Table handler * |
42 | *************************************************/ |
43 | |
44 | /* Internal header file defining the layout of the bits in each pair of 32-bit |
45 | words that form a data item in the table. */ |
46 | |
47 | typedef struct cnode { |
48 | unsigned f0; |
49 | unsigned f1; |
50 | } cnode; |
51 | |
52 | /* Things for the f0 field */ |
53 | |
54 | #define f0_scriptmask 0xff000000 /* Mask for script field */ |
55 | #define f0_scriptshift 24 /* Shift for script value */ |
56 | #define f0_rangeflag 0x00f00000 /* Flag for a range item */ |
57 | #define f0_charmask 0x001fffff /* Mask for code point value */ |
58 | |
59 | /* Things for the f1 field */ |
60 | |
61 | #define f1_typemask 0xfc000000 /* Mask for char type field */ |
62 | #define f1_typeshift 26 /* Shift for the type field */ |
63 | #define f1_rangemask 0x0000ffff /* Mask for a range offset */ |
64 | #define f1_casemask 0x0000ffff /* Mask for a case offset */ |
65 | #define f1_caseneg 0xffff8000 /* Bits for negation */ |
66 | |
67 | /* The data consists of a vector of structures of type cnode. The two unsigned |
68 | 32-bit integers are used as follows: |
69 | |
70 | (f0) (1) The most significant byte holds the script number. The numbers are |
71 | defined by the enum in ucp.h. |
72 | |
73 | (2) The 0x00800000 bit is set if this entry defines a range of characters. |
74 | It is not set if this entry defines a single character |
75 | |
76 | (3) The 0x00600000 bits are spare. |
77 | |
78 | (4) The 0x001fffff bits contain the code point. No Unicode code point will |
79 | ever be greater than 0x0010ffff, so this should be OK for ever. |
80 | |
81 | (f1) (1) The 0xfc000000 bits contain the character type number. The numbers are |
82 | defined by an enum in ucp.h. |
83 | |
84 | (2) The 0x03ff0000 bits are spare. |
85 | |
86 | (3) The 0x0000ffff bits contain EITHER the unsigned offset to the top of |
87 | range if this entry defines a range, OR the *signed* offset to the |
88 | character's "other case" partner if this entry defines a single |
89 | character. There is no partner if the value is zero. |
90 | |
91 | ------------------------------------------------------------------------------- |
92 | | script (8) |.|.|.| codepoint (21) || type (6) |.|.| spare (8) | offset (16) | |
93 | ------------------------------------------------------------------------------- |
94 | | | | | | |
95 | | | |-> spare | |-> spare |
96 | | | | |
97 | | |-> spare |-> spare |
98 | | |
99 | |-> range flag |
100 | |
101 | The upper/lower casing information is set only for characters that come in |
102 | pairs. The non-one-to-one mappings in the Unicode data are ignored. |
103 | |
104 | When searching the data, proceed as follows: |
105 | |
106 | (1) Set up for a binary chop search. |
107 | |
108 | (2) If the top is not greater than the bottom, the character is not in the |
109 | table. Its type must therefore be "Cn" ("Undefined"). |
110 | |
111 | (3) Find the middle vector element. |
112 | |
113 | (4) Extract the code point and compare. If equal, we are done. |
114 | |
115 | (5) If the test character is smaller, set the top to the current point, and |
116 | goto (2). |
117 | |
118 | (6) If the current entry defines a range, compute the last character by adding |
119 | the offset, and see if the test character is within the range. If it is, |
120 | we are done. |
121 | |
122 | (7) Otherwise, set the bottom to one element past the current point and goto |
123 | (2). |
124 | */ |
125 | |
126 | /* End of ucpinternal.h */ |
127 | |