xref: /aosp_15_r20/external/cronet/third_party/libxml/src/include/libxml/encoding.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 /*
2  * Summary: interface for the encoding conversion functions
3  * Description: interface for the encoding conversion functions needed for
4  *              XML basic encoding and iconv() support.
5  *
6  * Related specs are
7  * rfc2044        (UTF-8 and UTF-16) F. Yergeau Alis Technologies
8  * [ISO-10646]    UTF-8 and UTF-16 in Annexes
9  * [ISO-8859-1]   ISO Latin-1 characters codes.
10  * [UNICODE]      The Unicode Consortium, "The Unicode Standard --
11  *                Worldwide Character Encoding -- Version 1.0", Addison-
12  *                Wesley, Volume 1, 1991, Volume 2, 1992.  UTF-8 is
13  *                described in Unicode Technical Report #4.
14  * [US-ASCII]     Coded Character Set--7-bit American Standard Code for
15  *                Information Interchange, ANSI X3.4-1986.
16  *
17  * Copy: See Copyright for the status of this software.
18  *
19  * Author: Daniel Veillard
20  */
21 
22 #ifndef __XML_CHAR_ENCODING_H__
23 #define __XML_CHAR_ENCODING_H__
24 
25 #include <libxml/xmlversion.h>
26 
27 #ifdef LIBXML_ICONV_ENABLED
28 #include <iconv.h>
29 #endif
30 
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34 
35 typedef enum {
36     XML_ENC_ERR_SUCCESS     =  0,
37     XML_ENC_ERR_SPACE       = -1,
38     XML_ENC_ERR_INPUT       = -2,
39     XML_ENC_ERR_PARTIAL     = -3,
40     XML_ENC_ERR_INTERNAL    = -4,
41     XML_ENC_ERR_MEMORY      = -5
42 } xmlCharEncError;
43 
44 /*
45  * xmlCharEncoding:
46  *
47  * Predefined values for some standard encodings.
48  * Libxml does not do beforehand translation on UTF8 and ISOLatinX.
49  * It also supports ASCII, ISO-8859-1, and UTF16 (LE and BE) by default.
50  *
51  * Anything else would have to be translated to UTF8 before being
52  * given to the parser itself. The BOM for UTF16 and the encoding
53  * declaration are looked at and a converter is looked for at that
54  * point. If not found the parser stops here as asked by the XML REC. A
55  * converter can be registered by the user using xmlRegisterCharEncodingHandler
56  * but the current form doesn't allow stateful transcoding (a serious
57  * problem agreed !). If iconv has been found it will be used
58  * automatically and allow stateful transcoding, the simplest is then
59  * to be sure to enable iconv and to provide iconv libs for the encoding
60  * support needed.
61  *
62  * Note that the generic "UTF-16" is not a predefined value.  Instead, only
63  * the specific UTF-16LE and UTF-16BE are present.
64  */
65 typedef enum {
66     XML_CHAR_ENCODING_ERROR=   -1, /* No char encoding detected */
67     XML_CHAR_ENCODING_NONE=	0, /* No char encoding detected */
68     XML_CHAR_ENCODING_UTF8=	1, /* UTF-8 */
69     XML_CHAR_ENCODING_UTF16LE=	2, /* UTF-16 little endian */
70     XML_CHAR_ENCODING_UTF16BE=	3, /* UTF-16 big endian */
71     XML_CHAR_ENCODING_UCS4LE=	4, /* UCS-4 little endian */
72     XML_CHAR_ENCODING_UCS4BE=	5, /* UCS-4 big endian */
73     XML_CHAR_ENCODING_EBCDIC=	6, /* EBCDIC uh! */
74     XML_CHAR_ENCODING_UCS4_2143=7, /* UCS-4 unusual ordering */
75     XML_CHAR_ENCODING_UCS4_3412=8, /* UCS-4 unusual ordering */
76     XML_CHAR_ENCODING_UCS2=	9, /* UCS-2 */
77     XML_CHAR_ENCODING_8859_1=	10,/* ISO-8859-1 ISO Latin 1 */
78     XML_CHAR_ENCODING_8859_2=	11,/* ISO-8859-2 ISO Latin 2 */
79     XML_CHAR_ENCODING_8859_3=	12,/* ISO-8859-3 */
80     XML_CHAR_ENCODING_8859_4=	13,/* ISO-8859-4 */
81     XML_CHAR_ENCODING_8859_5=	14,/* ISO-8859-5 */
82     XML_CHAR_ENCODING_8859_6=	15,/* ISO-8859-6 */
83     XML_CHAR_ENCODING_8859_7=	16,/* ISO-8859-7 */
84     XML_CHAR_ENCODING_8859_8=	17,/* ISO-8859-8 */
85     XML_CHAR_ENCODING_8859_9=	18,/* ISO-8859-9 */
86     XML_CHAR_ENCODING_2022_JP=  19,/* ISO-2022-JP */
87     XML_CHAR_ENCODING_SHIFT_JIS=20,/* Shift_JIS */
88     XML_CHAR_ENCODING_EUC_JP=   21,/* EUC-JP */
89     XML_CHAR_ENCODING_ASCII=    22 /* pure ASCII */
90 } xmlCharEncoding;
91 
92 /**
93  * xmlCharEncodingInputFunc:
94  * @out:  a pointer to an array of bytes to store the UTF-8 result
95  * @outlen:  the length of @out
96  * @in:  a pointer to an array of chars in the original encoding
97  * @inlen:  the length of @in
98  *
99  * Take a block of chars in the original encoding and try to convert
100  * it to an UTF-8 block of chars out.
101  *
102  * Returns the number of bytes written, -1 if lack of space, or -2
103  *     if the transcoding failed.
104  * The value of @inlen after return is the number of octets consumed
105  *     if the return value is positive, else unpredictiable.
106  * The value of @outlen after return is the number of octets consumed.
107  */
108 typedef int (* xmlCharEncodingInputFunc)(unsigned char *out, int *outlen,
109                                          const unsigned char *in, int *inlen);
110 
111 
112 /**
113  * xmlCharEncodingOutputFunc:
114  * @out:  a pointer to an array of bytes to store the result
115  * @outlen:  the length of @out
116  * @in:  a pointer to an array of UTF-8 chars
117  * @inlen:  the length of @in
118  *
119  * Take a block of UTF-8 chars in and try to convert it to another
120  * encoding.
121  * Note: a first call designed to produce heading info is called with
122  * in = NULL. If stateful this should also initialize the encoder state.
123  *
124  * Returns the number of bytes written, -1 if lack of space, or -2
125  *     if the transcoding failed.
126  * The value of @inlen after return is the number of octets consumed
127  *     if the return value is positive, else unpredictiable.
128  * The value of @outlen after return is the number of octets produced.
129  */
130 typedef int (* xmlCharEncodingOutputFunc)(unsigned char *out, int *outlen,
131                                           const unsigned char *in, int *inlen);
132 
133 
134 /*
135  * Block defining the handlers for non UTF-8 encodings.
136  * If iconv is supported, there are two extra fields.
137  */
138 typedef struct _xmlCharEncodingHandler xmlCharEncodingHandler;
139 typedef xmlCharEncodingHandler *xmlCharEncodingHandlerPtr;
140 struct _xmlCharEncodingHandler {
141     char                       *name;
142     xmlCharEncodingInputFunc   input;
143     xmlCharEncodingOutputFunc  output;
144 #ifdef LIBXML_ICONV_ENABLED
145     iconv_t                    iconv_in;
146     iconv_t                    iconv_out;
147 #endif /* LIBXML_ICONV_ENABLED */
148 #ifdef LIBXML_ICU_ENABLED
149     struct _uconv_t            *uconv_in;
150     struct _uconv_t            *uconv_out;
151 #endif /* LIBXML_ICU_ENABLED */
152 };
153 
154 /*
155  * Interfaces for encoding handlers.
156  */
157 XML_DEPRECATED
158 XMLPUBFUN void
159 	xmlInitCharEncodingHandlers	(void);
160 XML_DEPRECATED
161 XMLPUBFUN void
162 	xmlCleanupCharEncodingHandlers	(void);
163 XMLPUBFUN void
164 	xmlRegisterCharEncodingHandler	(xmlCharEncodingHandlerPtr handler);
165 XMLPUBFUN int
166 	xmlLookupCharEncodingHandler	(xmlCharEncoding enc,
167 					 xmlCharEncodingHandlerPtr *out);
168 XMLPUBFUN int
169 	xmlOpenCharEncodingHandler	(const char *name,
170 					 int output,
171 					 xmlCharEncodingHandlerPtr *out);
172 XMLPUBFUN xmlCharEncodingHandlerPtr
173 	xmlGetCharEncodingHandler	(xmlCharEncoding enc);
174 XMLPUBFUN xmlCharEncodingHandlerPtr
175 	xmlFindCharEncodingHandler	(const char *name);
176 XMLPUBFUN xmlCharEncodingHandlerPtr
177 	xmlNewCharEncodingHandler	(const char *name,
178 					 xmlCharEncodingInputFunc input,
179 					 xmlCharEncodingOutputFunc output);
180 
181 /*
182  * Interfaces for encoding names and aliases.
183  */
184 XMLPUBFUN int
185 	xmlAddEncodingAlias		(const char *name,
186 					 const char *alias);
187 XMLPUBFUN int
188 	xmlDelEncodingAlias		(const char *alias);
189 XMLPUBFUN const char *
190 	xmlGetEncodingAlias		(const char *alias);
191 XMLPUBFUN void
192 	xmlCleanupEncodingAliases	(void);
193 XMLPUBFUN xmlCharEncoding
194 	xmlParseCharEncoding		(const char *name);
195 XMLPUBFUN const char *
196 	xmlGetCharEncodingName		(xmlCharEncoding enc);
197 
198 /*
199  * Interfaces directly used by the parsers.
200  */
201 XMLPUBFUN xmlCharEncoding
202 	xmlDetectCharEncoding		(const unsigned char *in,
203 					 int len);
204 
205 struct _xmlBuffer;
206 XMLPUBFUN int
207 	xmlCharEncOutFunc		(xmlCharEncodingHandler *handler,
208 					 struct _xmlBuffer *out,
209 					 struct _xmlBuffer *in);
210 
211 XMLPUBFUN int
212 	xmlCharEncInFunc		(xmlCharEncodingHandler *handler,
213 					 struct _xmlBuffer *out,
214 					 struct _xmlBuffer *in);
215 XML_DEPRECATED
216 XMLPUBFUN int
217 	xmlCharEncFirstLine		(xmlCharEncodingHandler *handler,
218 					 struct _xmlBuffer *out,
219 					 struct _xmlBuffer *in);
220 XMLPUBFUN int
221 	xmlCharEncCloseFunc		(xmlCharEncodingHandler *handler);
222 
223 /*
224  * Export a few useful functions
225  */
226 #ifdef LIBXML_OUTPUT_ENABLED
227 XMLPUBFUN int
228 	UTF8Toisolat1			(unsigned char *out,
229 					 int *outlen,
230 					 const unsigned char *in,
231 					 int *inlen);
232 #endif /* LIBXML_OUTPUT_ENABLED */
233 XMLPUBFUN int
234 	isolat1ToUTF8			(unsigned char *out,
235 					 int *outlen,
236 					 const unsigned char *in,
237 					 int *inlen);
238 #ifdef __cplusplus
239 }
240 #endif
241 
242 #endif /* __XML_CHAR_ENCODING_H__ */
243