1 /*
2 __ __ _
3 ___\ \/ /_ __ __ _| |_
4 / _ \\ /| '_ \ / _` | __|
5 | __// \| |_) | (_| | |_
6 \___/_/\_\ .__/ \__,_|\__|
7 |_| XML parser
8
9 Copyright (c) 1997-2000 Thai Open Source Software Center Ltd
10 Copyright (c) 2002 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
11 Copyright (c) 2016-2017 Sebastian Pipping <sebastian@pipping.org>
12 Licensed under the MIT license:
13
14 Permission is hereby granted, free of charge, to any person obtaining
15 a copy of this software and associated documentation files (the
16 "Software"), to deal in the Software without restriction, including
17 without limitation the rights to use, copy, modify, merge, publish,
18 distribute, sublicense, and/or sell copies of the Software, and to permit
19 persons to whom the Software is furnished to do so, subject to the
20 following conditions:
21
22 The above copyright notice and this permission notice shall be included
23 in all copies or substantial portions of the Software.
24
25 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
28 NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
29 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
30 OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
31 USE OR OTHER DEALINGS IN THE SOFTWARE.
32 */
33
34 #define CHARSET_MAX 41
35
36 static const char *
getTok(const char ** pp)37 getTok(const char **pp) {
38 enum { inAtom, inString, init, inComment };
39 int state = init;
40 const char *tokStart = 0;
41 for (;;) {
42 switch (**pp) {
43 case '\0':
44 return 0;
45 case ' ':
46 case '\r':
47 case '\t':
48 case '\n':
49 if (state == inAtom)
50 return tokStart;
51 break;
52 case '(':
53 if (state == inAtom)
54 return tokStart;
55 if (state != inString)
56 state++;
57 break;
58 case ')':
59 if (state > init)
60 --state;
61 else if (state != inString)
62 return 0;
63 break;
64 case ';':
65 case '/':
66 case '=':
67 if (state == inAtom)
68 return tokStart;
69 if (state == init)
70 return (*pp)++;
71 break;
72 case '\\':
73 ++*pp;
74 if (**pp == '\0')
75 return 0;
76 break;
77 case '"':
78 switch (state) {
79 case inString:
80 ++*pp;
81 return tokStart;
82 case inAtom:
83 return tokStart;
84 case init:
85 tokStart = *pp;
86 state = inString;
87 break;
88 }
89 break;
90 default:
91 if (state == init) {
92 tokStart = *pp;
93 state = inAtom;
94 }
95 break;
96 }
97 ++*pp;
98 }
99 /* not reached */
100 }
101
102 /* key must be lowercase ASCII */
103
104 static int
matchkey(const char * start,const char * end,const char * key)105 matchkey(const char *start, const char *end, const char *key) {
106 if (! start)
107 return 0;
108 for (; start != end; start++, key++)
109 if (*start != *key && *start != 'A' + (*key - 'a'))
110 return 0;
111 return *key == '\0';
112 }
113
114 void
getXMLCharset(const char * buf,char * charset)115 getXMLCharset(const char *buf, char *charset) {
116 const char *next, *p;
117
118 charset[0] = '\0';
119 next = buf;
120 p = getTok(&next);
121 if (matchkey(p, next, "text"))
122 strcpy(charset, "us-ascii");
123 else if (! matchkey(p, next, "application"))
124 return;
125 p = getTok(&next);
126 if (! p || *p != '/')
127 return;
128 p = getTok(&next);
129 if (matchkey(p, next, "xml"))
130 isXml = 1;
131 p = getTok(&next);
132 while (p) {
133 if (*p == ';') {
134 p = getTok(&next);
135 if (matchkey(p, next, "charset")) {
136 p = getTok(&next);
137 if (p && *p == '=') {
138 p = getTok(&next);
139 if (p) {
140 char *s = charset;
141 if (*p == '"') {
142 while (++p != next - 1) {
143 if (*p == '\\')
144 ++p;
145 if (s == charset + CHARSET_MAX - 1) {
146 charset[0] = '\0';
147 break;
148 }
149 *s++ = *p;
150 }
151 *s++ = '\0';
152 } else {
153 if (next - p > CHARSET_MAX - 1)
154 break;
155 while (p != next)
156 *s++ = *p++;
157 *s = 0;
158 break;
159 }
160 }
161 }
162 }
163 } else
164 p = getTok(&next);
165 }
166 }
167
168 int
main(int argc,char ** argv)169 main(int argc, char **argv) {
170 char buf[CHARSET_MAX];
171 getXMLCharset(argv[1], buf);
172 printf("charset = \"%s\"\n", buf);
173 return 0;
174 }
175