[glibc.git] / libidn / punycode.h

/* punycode.h	Declarations for punycode functions.
 * Copyright (C) 2002, 2003  Simon Josefsson
 *
 * This file is part of GNU Libidn.
 *
 * GNU Libidn is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * GNU Libidn is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with GNU Libidn; if not, see <http://www.gnu.org/licenses/>.
 */

/*
 * This file is derived from RFC 3492bis written by Adam M. Costello.
 *
 * Disclaimer and license: Regarding this entire document or any
 * portion of it (including the pseudocode and C code), the author
 * makes no guarantees and is not responsible for any damage resulting
 * from its use.  The author grants irrevocable permission to anyone
 * to use, modify, and distribute it in any way that does not diminish
 * the rights of anyone else to use, modify, and distribute it,
 * provided that redistributed derivative works do not contain
 * misleading author or version information.  Derivative works need
 * not be licensed under similar terms.
 *
 * Copyright (C) The Internet Society (2003).  All Rights Reserved.
 *
 * This document and translations of it may be copied and furnished to
 * others, and derivative works that comment on or otherwise explain it
 * or assist in its implementation may be prepared, copied, published
 * and distributed, in whole or in part, without restriction of any
 * kind, provided that the above copyright notice and this paragraph are
 * included on all such copies and derivative works.  However, this
 * document itself may not be modified in any way, such as by removing
 * the copyright notice or references to the Internet Society or other
 * Internet organizations, except as needed for the purpose of
 * developing Internet standards in which case the procedures for
 * copyrights defined in the Internet Standards process must be
 * followed, or as required to translate it into languages other than
 * English.
 *
 * The limited permissions granted above are perpetual and will not be
 * revoked by the Internet Society or its successors or assigns.
 *
 * This document and the information contained herein is provided on an
 * "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
 * TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
 * HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef _PUNYCODE_H
#define _PUNYCODE_H

#ifdef __cplusplus
extern "C"
{
#endif

#include <stddef.h>		/* size_t */
#include <stdint.h>		/* uint32_t */

  enum punycode_status
  {
    punycode_success = 0,
    punycode_bad_input = 1,	/* Input is invalid.                       */
    punycode_big_output = 2,	/* Output would exceed the space provided. */
    punycode_overflow = 3	/* Wider integers needed to process input. */
  };

  typedef enum
  {
    PUNYCODE_SUCCESS = punycode_success,
    PUNYCODE_BAD_INPUT = punycode_bad_input,
    PUNYCODE_BIG_OUTPUT = punycode_big_output,
    PUNYCODE_OVERFLOW = punycode_overflow
  } Punycode_status;

/* punycode_uint needs to be unsigned and needs to be */
/* at least 26 bits wide.                             */

  typedef uint32_t punycode_uint;

  extern int punycode_encode (size_t input_length,
			      const punycode_uint input[],
			      const unsigned char case_flags[],
			      size_t * output_length, char output[]);

/*
    punycode_encode() converts a sequence of code points (presumed to be
    Unicode code points) to Punycode.

    Input arguments (to be supplied by the caller):

        input_length
            The number of code points in the input array and the number
            of flags in the case_flags array.

        input
            An array of code points.  They are presumed to be Unicode
            code points, but that is not strictly REQUIRED.  The
            array contains code points, not code units.  UTF-16 uses
            code units D800 through DFFF to refer to code points
            10000..10FFFF.  The code points D800..DFFF do not occur in
            any valid Unicode string.  The code points that can occur in
            Unicode strings (0..D7FF and E000..10FFFF) are also called
            Unicode scalar values.

        case_flags
            A null pointer or an array of boolean values parallel to
            the input array.  Nonzero (true, flagged) suggests that the
            corresponding Unicode character be forced to uppercase after
            being decoded (if possible), and zero (false, unflagged)
            suggests that it be forced to lowercase (if possible).
            ASCII code points (0..7F) are encoded literally, except that
            ASCII letters are forced to uppercase or lowercase according
            to the corresponding case flags.  If case_flags is a null
            pointer then ASCII letters are left as they are, and other
            code points are treated as unflagged.

    Output arguments (to be filled in by the function):

        output
            An array of ASCII code points.  It is *not* null-terminated;
            it will contain zeros if and only if the input contains
            zeros.  (Of course the caller can leave room for a
            terminator and add one if needed.)

    Input/output arguments (to be supplied by the caller and overwritten
    by the function):

        output_length
            The caller passes in the maximum number of ASCII code points
            that it can receive.  On successful return it will contain
            the number of ASCII code points actually output.

    Return value:

        Can be any of the punycode_status values defined above except
        punycode_bad_input.  If not punycode_success, then output_size
        and output might contain garbage.
*/

  extern int punycode_decode (size_t input_length,
			      const char input[],
			      size_t * output_length,
			      punycode_uint output[],
			      unsigned char case_flags[]);

/*
    punycode_decode() converts Punycode to a sequence of code points
    (presumed to be Unicode code points).

    Input arguments (to be supplied by the caller):

        input_length
            The number of ASCII code points in the input array.

        input
            An array of ASCII code points (0..7F).

    Output arguments (to be filled in by the function):

        output
            An array of code points like the input argument of
            punycode_encode() (see above).

        case_flags
            A null pointer (if the flags are not needed by the caller)
            or an array of boolean values parallel to the output array.
            Nonzero (true, flagged) suggests that the corresponding
            Unicode character be forced to uppercase by the caller (if
            possible), and zero (false, unflagged) suggests that it
            be forced to lowercase (if possible).  ASCII code points
            (0..7F) are output already in the proper case, but their
            flags will be set appropriately so that applying the flags
            would be harmless.

    Input/output arguments (to be supplied by the caller and overwritten
    by the function):

        output_length
            The caller passes in the maximum number of code points
            that it can receive into the output array (which is also
            the maximum number of flags that it can receive into the
            case_flags array, if case_flags is not a null pointer).  On
            successful return it will contain the number of code points
            actually output (which is also the number of flags actually
            output, if case_flags is not a null pointer).  The decoder
            will never need to output more code points than the number
            of ASCII code points in the input, because of the way the
            encoding is defined.  The number of code points output
            cannot exceed the maximum possible value of a punycode_uint,
            even if the supplied output_length is greater than that.

    Return value:

        Can be any of the punycode_status values defined above.  If not
        punycode_success, then output_length, output, and case_flags
        might contain garbage.
*/

#ifdef __cplusplus
}
#endif
#endif				/* _PUNYCODE_H */
Commit	Line	Data
01859b1c UD	1	/* punycode.h Declarations for punycode functions.
	2	* Copyright (C) 2002, 2003 Simon Josefsson
	3	*
	4	* This file is part of GNU Libidn.
	5	*
	6	* GNU Libidn is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; either
	9	* version 2.1 of the License, or (at your option) any later version.
	10	*
	11	* GNU Libidn is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
59ba27a6	17	* License along with GNU Libidn; if not, see <http://www.gnu.org/licenses/>.
01859b1c UD	18	*/
	19
	20	/*
	21	* This file is derived from RFC 3492bis written by Adam M. Costello.
	22	*
	23	* Disclaimer and license: Regarding this entire document or any
	24	* portion of it (including the pseudocode and C code), the author
	25	* makes no guarantees and is not responsible for any damage resulting
	26	* from its use. The author grants irrevocable permission to anyone
	27	* to use, modify, and distribute it in any way that does not diminish
	28	* the rights of anyone else to use, modify, and distribute it,
	29	* provided that redistributed derivative works do not contain
	30	* misleading author or version information. Derivative works need
	31	* not be licensed under similar terms.
	32	*
	33	* Copyright (C) The Internet Society (2003). All Rights Reserved.
	34	*
	35	* This document and translations of it may be copied and furnished to
	36	* others, and derivative works that comment on or otherwise explain it
	37	* or assist in its implementation may be prepared, copied, published
	38	* and distributed, in whole or in part, without restriction of any
	39	* kind, provided that the above copyright notice and this paragraph are
	40	* included on all such copies and derivative works. However, this
	41	* document itself may not be modified in any way, such as by removing
	42	* the copyright notice or references to the Internet Society or other
	43	* Internet organizations, except as needed for the purpose of
	44	* developing Internet standards in which case the procedures for
	45	* copyrights defined in the Internet Standards process must be
	46	* followed, or as required to translate it into languages other than
	47	* English.
	48	*
	49	* The limited permissions granted above are perpetual and will not be
	50	* revoked by the Internet Society or its successors or assigns.
	51	*
	52	* This document and the information contained herein is provided on an
	53	* "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
	54	* TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
	55	* BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
	56	* HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
	57	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	58	*/
	59
	60	#ifndef _PUNYCODE_H
	61	#define _PUNYCODE_H
	62
	63	#ifdef __cplusplus
	64	extern "C"
	65	{
	66	#endif
	67
	68	#include <stddef.h> /* size_t */
	69	#include <stdint.h> /* uint32_t */
	70
	71	enum punycode_status
	72	{
	73	punycode_success = 0,
	74	punycode_bad_input = 1, /* Input is invalid. */
	75	punycode_big_output = 2, /* Output would exceed the space provided. */
	76	punycode_overflow = 3 /* Wider integers needed to process input. */
	77	};
	78
	79	typedef enum
	80	{
	81	PUNYCODE_SUCCESS = punycode_success,
82	PUNYCODE_BAD_INPUT = punycode_bad_input,
83	PUNYCODE_BIG_OUTPUT = punycode_big_output,
84	PUNYCODE_OVERFLOW = punycode_overflow
85	} Punycode_status;
86
87	/* punycode_uint needs to be unsigned and needs to be */
88	/* at least 26 bits wide. */
89
90	typedef uint32_t punycode_uint;
91
92	extern int punycode_encode (size_t input_length,
93	const punycode_uint input[],
94	const unsigned char case_flags[],
95	size_t * output_length, char output[]);
96
97	/*
98	punycode_encode() converts a sequence of code points (presumed to be
99	Unicode code points) to Punycode.
100
101	Input arguments (to be supplied by the caller):
102
103	input_length
104	The number of code points in the input array and the number
105	of flags in the case_flags array.
106
107	input
108	An array of code points. They are presumed to be Unicode
109	code points, but that is not strictly REQUIRED. The
110	array contains code points, not code units. UTF-16 uses
111	code units D800 through DFFF to refer to code points
112	10000..10FFFF. The code points D800..DFFF do not occur in
113	any valid Unicode string. The code points that can occur in
114	Unicode strings (0..D7FF and E000..10FFFF) are also called
115	Unicode scalar values.
116
117	case_flags
118	A null pointer or an array of boolean values parallel to
119	the input array. Nonzero (true, flagged) suggests that the
120	corresponding Unicode character be forced to uppercase after
121	being decoded (if possible), and zero (false, unflagged)
122	suggests that it be forced to lowercase (if possible).
123	ASCII code points (0..7F) are encoded literally, except that
124	ASCII letters are forced to uppercase or lowercase according
125	to the corresponding case flags. If case_flags is a null
126	pointer then ASCII letters are left as they are, and other
127	code points are treated as unflagged.
128
129	Output arguments (to be filled in by the function):
130
131	output
132	An array of ASCII code points. It is not null-terminated;
133	it will contain zeros if and only if the input contains
134	zeros. (Of course the caller can leave room for a
135	terminator and add one if needed.)
136
137	Input/output arguments (to be supplied by the caller and overwritten
138	by the function):
139
140	output_length
141	The caller passes in the maximum number of ASCII code points
142	that it can receive. On successful return it will contain
143	the number of ASCII code points actually output.
144
145	Return value:
146
147	Can be any of the punycode_status values defined above except
148	punycode_bad_input. If not punycode_success, then output_size
149	and output might contain garbage.
150	*/
151
152	extern int punycode_decode (size_t input_length,
153	const char input[],
154	size_t * output_length,
155	punycode_uint output[],
156	unsigned char case_flags[]);
157
158	/*
159	punycode_decode() converts Punycode to a sequence of code points
160	(presumed to be Unicode code points).
161
162	Input arguments (to be supplied by the caller):
163
164	input_length
165	The number of ASCII code points in the input array.
166
167	input
168	An array of ASCII code points (0..7F).
169
170	Output arguments (to be filled in by the function):
171
172	output
173	An array of code points like the input argument of
174	punycode_encode() (see above).
175
176	case_flags
177	A null pointer (if the flags are not needed by the caller)
178	or an array of boolean values parallel to the output array.
179	Nonzero (true, flagged) suggests that the corresponding
180	Unicode character be forced to uppercase by the caller (if
181	possible), and zero (false, unflagged) suggests that it
182	be forced to lowercase (if possible). ASCII code points
183	(0..7F) are output already in the proper case, but their
184	flags will be set appropriately so that applying the flags
185	would be harmless.
186
187	Input/output arguments (to be supplied by the caller and overwritten
188	by the function):
189
190	output_length
191	The caller passes in the maximum number of code points
192	that it can receive into the output array (which is also
193	the maximum number of flags that it can receive into the
194	case_flags array, if case_flags is not a null pointer). On
195	successful return it will contain the number of code points
196	actually output (which is also the number of flags actually
197	output, if case_flags is not a null pointer). The decoder
198	will never need to output more code points than the number
199	of ASCII code points in the input, because of the way the
200	encoding is defined. The number of code points output
201	cannot exceed the maximum possible value of a punycode_uint,
202	even if the supplied output_length is greater than that.
203
204	Return value:
205
206	Can be any of the punycode_status values defined above. If not
207	punycode_success, then output_length, output, and case_flags
208	might contain garbage.
209	*/
210
211	#ifdef __cplusplus
212	}
213	#endif
214	#endif /* _PUNYCODE_H */