Files
bind9/contrib/idn/mdnkit/lib/utf6.c
2001-06-09 00:30:55 +00:00

552 lines
13 KiB
C

#ifndef lint
static char *rcsid = "$Id: utf6.c,v 1.1 2001/06/09 00:30:30 tale Exp $";
#endif
/*
* Copyright (c) 2000 Japan Network Information Center. All rights reserved.
*
* By using this file, you agree to the terms and conditions set forth bellow.
*
* LICENSE TERMS AND CONDITIONS
*
* The following License Terms and Conditions apply, unless a different
* license is obtained from Japan Network Information Center ("JPNIC"),
* a Japanese association, Fuundo Bldg., 1-2 Kanda Ogawamachi, Chiyoda-ku,
* Tokyo, Japan.
*
* 1. Use, Modification and Redistribution (including distribution of any
* modified or derived work) in source and/or binary forms is permitted
* under this License Terms and Conditions.
*
* 2. Redistribution of source code must retain the copyright notices as they
* appear in each source code file, this License Terms and Conditions.
*
* 3. Redistribution in binary form must reproduce the Copyright Notice,
* this License Terms and Conditions, in the documentation and/or other
* materials provided with the distribution. For the purposes of binary
* distribution the "Copyright Notice" refers to the following language:
* "Copyright (c) Japan Network Information Center. All rights reserved."
*
* 4. Neither the name of JPNIC may be used to endorse or promote products
* derived from this Software without specific prior written approval of
* JPNIC.
*
* 5. Disclaimer/Limitation of Liability: THIS SOFTWARE IS PROVIDED BY JPNIC
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JPNIC BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* 6. Indemnification by Licensee
* Any person or entities using and/or redistributing this Software under
* this License Terms and Conditions shall defend indemnify and hold
* harmless JPNIC from and against any and all judgements damages,
* expenses, settlement liabilities, cost and other liabilities of any
* kind as a result of use and redistribution of this Software or any
* claim, suite, action, litigation or proceeding by any third party
* arising out of or relates to this License Terms and Conditions.
*
* 7. Governing Law, Jurisdiction and Venue
* This License Terms and Conditions shall be governed by and and
* construed in accordance with the law of Japan. Any person or entities
* using and/or redistributing this Software under this License Terms and
* Conditions hereby agrees and consent to the personal and exclusive
* jurisdiction and venue of Tokyo District Court of Japan.
*/
#include <config.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <mdn/result.h>
#include <mdn/assert.h>
#include <mdn/logmacro.h>
#include <mdn/converter.h>
#include <mdn/utf8.h>
#include <mdn/debug.h>
#include <mdn/utf6.h>
#include <mdn/ace.h>
#include <mdn/util.h>
#ifndef MDN_UTF6_PREFIX
#define MDN_UTF6_PREFIX "wq--"
#endif
#define UTF6_SAME_BYTE_MASK 0x00ff
#define UTF6_SAME_NIBBLE_MASK 0x0fff
#define UTF6_PLAIN_MASK 0xffff
#define UTF6_BUF_SIZE 128 /* more than enough */
/*
* Compression type.
*/
enum {
same_byte_mode, /* the most significant byte of all non
'-' characters is the same value */
same_nibble_mode, /* the most significant nibble of all non
'-' characters is the same value */
plain_mode /* not compressed */
};
static mdn_result_t utf6_decode(const char *from, size_t fromlen,
char *to, size_t tolen);
static mdn_result_t utf6_decode_utf16(const char *from, size_t fromlen,
unsigned short *buf, size_t *lenp);
static mdn_result_t utf6_decode_vlhex(const char *from, size_t len,
size_t *reslen,
unsigned short *value);
static mdn_result_t utf6_encode(const char *from, size_t fromlen,
char *to, size_t tolen);
static mdn_result_t utf6_encode_utf16(const unsigned short *p,
size_t len, char *to, size_t tolen,
int compress);
static mdn_result_t utf6_encode_vlhex(unsigned short value, char *to,
size_t tolen, size_t *reslen);
static int get_compress_mode(const unsigned short *p, size_t len);
static mdn__ace_t utf6_ctx = {
mdn__ace_prefix,
MDN_UTF6_PREFIX,
utf6_encode,
utf6_decode,
};
/* ARGSUSED */
mdn_result_t
mdn__utf6_open(mdn_converter_t ctx, mdn_converter_dir_t dir, void **privdata) {
return (mdn_success);
}
/* ARGSUSED */
mdn_result_t
mdn__utf6_close(mdn_converter_t ctx, void *privdata, mdn_converter_dir_t dir) {
return (mdn_success);
}
mdn_result_t
mdn__utf6_convert(mdn_converter_t ctx, void *privdata, mdn_converter_dir_t dir,
const char *from, char *to, size_t tolen)
{
mdn_result_t r;
assert(ctx != NULL &&
(dir == mdn_converter_l2u || dir == mdn_converter_u2l));
TRACE(("mdn__utf6_convert(dir=%s,from=\"%s\")\n",
dir == mdn_converter_l2u ? "l2u" : "u2l",
mdn_debug_xstring(from, 20)));
r = mdn__ace_convert(&utf6_ctx, dir, from, to, tolen);
if (r != mdn_success)
return (r);
DUMP(("mdn__utf6_convert: \"%s\"\n", mdn_debug_xstring(to, 70)));
return (r);
}
static mdn_result_t
utf6_decode(const char *from, size_t fromlen, char *to, size_t tolen) {
unsigned short *buf;
unsigned short local_buf[UTF6_BUF_SIZE];
size_t len, reslen;
mdn_result_t r;
/*
* Allocate sufficient buffer.
*/
if (fromlen > UTF6_BUF_SIZE) {
if ((buf = malloc(sizeof(*buf) * fromlen)) == NULL)
return (mdn_nomemory);
} else {
/* Use local buffer. */
buf = local_buf;
}
/*
* Decode base32 and decompress.
*/
r = utf6_decode_utf16(from, fromlen, buf, &len);
if (r != mdn_success)
goto ret;
/*
* Now 'buf' holds the decompressed string, which must contain
* UTF-16 characters. Convert them into UTF-8.
*/
r = mdn_util_utf16toutf8(buf, len, to, tolen, &reslen);
if (r != mdn_success)
goto ret;
/*
* Terminate with NUL.
*/
if (tolen <= reslen) {
r = mdn_buffer_overflow;
goto ret;
}
to += reslen;
*to = '\0';
tolen -= reslen;
r = mdn_success;
ret:
if (buf != local_buf)
free(buf);
return (r);
}
static mdn_result_t
utf6_decode_utf16(const char *from, size_t fromlen,
unsigned short *buf, size_t *lenp)
{
mdn_result_t r;
unsigned short value;
unsigned short cpart;
unsigned short vmax;
size_t len;
size_t reslen;
/*
* Decode Base32 and put the result bytes to 'buf'.
* Since decoded string will be shorter in length, and
* the caller allocated 'buf' so that its length is not
* less than 'fromlen', we don't have to worry about overflow.
*/
if (fromlen <= 0)
return mdn_success;
switch (*from) {
case 'y':
case 'Y':
/*
* same_byte_mode.
*/
fromlen--;
from++;
r = utf6_decode_vlhex(from, fromlen, &reslen, &value);
if (r != mdn_success)
return (mdn_invalid_encoding);
from += reslen;
fromlen -= reslen;
cpart = value * 0x0100;
vmax = 0x00ff;
break;
case 'z':
case 'Z':
/*
* same_nibble_mode.
*/
fromlen--;
from++;
r = utf6_decode_vlhex(from, fromlen, &reslen, &value);
if (r != mdn_success)
return (mdn_invalid_encoding);
from += reslen;
fromlen -= reslen;
cpart = value * 0x1000;
vmax = 0x0fff;
break;
default:
/*
* plain_mode.
*/
cpart = 0x0000;
vmax = 0xffff;
break;
}
for (len = 0; fromlen > 0; len++) {
if (*from == '-') {
*buf++ = '-';
from++;
fromlen--;
} else {
r = utf6_decode_vlhex(from, fromlen, &reslen, &value);
if (r != mdn_success)
return (mdn_invalid_encoding);
if (value > vmax)
return (mdn_invalid_encoding);
*buf++ = cpart + value;
from += reslen;
fromlen -= reslen;
}
}
*buf = '\0';
*lenp = len;
return (mdn_success);
}
static mdn_result_t
utf6_decode_vlhex(const char *from, size_t len, size_t *reslen,
unsigned short *value) {
unsigned short v;
int i;
/*
* Decode the first character of a variable length HEX string.
* The character must be in set of [ghijklmnopqrstuv].
*/
if (len <= 0)
return (mdn_invalid_encoding);
if ('G' <= *from && *from <= 'V')
v = *from - 'G';
else if ('g' <= *from && *from <= 'v')
v = *from - 'g';
else
return (mdn_invalid_encoding);
from++;
len--;
i = 1;
/*
* Decode the rest characters of a variable length HEX string.
* The every character must be in set of [0123456789abcdef].
*/
for (;;) {
if (len <= 0)
break;
if ('0' <= *from && *from <= '9')
v = (v << 4) + (*from - '0');
else if ('A' <= *from && *from <= 'F')
v = (v << 4) + 0x0a + (*from - 'A');
else if ('a' <= *from && *from <= 'f')
v = (v << 4) + 0x0a + (*from - 'a');
else
break;
from++;
len--;
i++;
}
*value = v;
*reslen = i;
return (mdn_success);
}
static mdn_result_t
utf6_encode(const char *from, size_t fromlen, char *to, size_t tolen) {
unsigned short *buf;
unsigned short local_buf[UTF6_BUF_SIZE]; /* UTF-16 */
mdn_result_t r;
size_t buflen, len;
/*
* Convert to UTF-16.
*/
buf = local_buf;
buflen = UTF6_BUF_SIZE;
for (;;) {
r = mdn_util_utf8toutf16(from, fromlen,
buf, buflen, &len);
if (r == mdn_buffer_overflow) {
buflen *= 2;
if (buf == local_buf)
buf = malloc(sizeof(*buf) * buflen);
else
buf = realloc(buf, sizeof(*buf) * buflen);
if (buf == NULL)
return (mdn_nomemory);
} else if (r == mdn_success) {
break;
} else {
goto ret;
}
}
/*
* Compress, encode in base-32 and output.
*/
r = utf6_encode_utf16(buf, len, to, tolen,
get_compress_mode(buf, len));
ret:
if (buf != local_buf)
free(buf);
return (r);
}
static mdn_result_t
utf6_encode_utf16(const unsigned short *p, size_t len,
char *to, size_t tolen, int compress_mode)
{
mdn_result_t r;
unsigned short mask;
size_t reslen;
int i;
if (len <= 0)
return mdn_success;
switch (compress_mode) {
case same_byte_mode:
mask = UTF6_SAME_BYTE_MASK;
if (tolen < 1)
return (mdn_buffer_overflow);
*to++ = 'y';
tolen--;
r = utf6_encode_vlhex((p[0] >> 8) & 0x00ff, to, tolen,
&reslen);
if (r != mdn_success)
return (r);
to += reslen;
tolen -= reslen;
break;
case same_nibble_mode:
mask = UTF6_SAME_NIBBLE_MASK;
if (tolen < 1)
return (mdn_buffer_overflow);
*to++ = 'z';
tolen--;
r = utf6_encode_vlhex((p[0] >> 4) & 0x0fff, to, tolen,
&reslen);
if (r != mdn_success)
return (r);
to += reslen;
tolen -= reslen;
break;
default:
mask = UTF6_PLAIN_MASK;
break;
}
for (i = 0; i < len; i++) {
if (p[i] == '-') {
if (tolen < 1)
return (mdn_buffer_overflow);
*to++ = '-';
tolen--;
} else {
r = utf6_encode_vlhex(p[i] & mask, to, tolen, &reslen);
if (r != mdn_success)
return (r);
to += reslen;
tolen -= reslen;
}
}
if (tolen <= 0)
return (mdn_buffer_overflow);
*to = '\0';
return (mdn_success);
}
static mdn_result_t
utf6_encode_vlhex(unsigned short value, char *to, size_t tolen,
size_t *reslen) {
static const char *vlhex_string1 = "ghijklmnopqrstuv";
static const char *vlhex_string2 = "0123456789abcdef";
/*
* Encode an integer in the range of 0x000 - 0xffff as variable
* length HEX string.
*/
if (value <= 0x000f) {
if (tolen < 1)
return (mdn_buffer_overflow);
*to++ = vlhex_string1[ value & 0x0f];
*reslen = 1;
} else if (value <= 0x00ff) {
if (tolen < 2)
return (mdn_buffer_overflow);
*to++ = vlhex_string1[(value >> 4) & 0x0f];
*to++ = vlhex_string2[ value & 0x0f];
*reslen = 2;
} else if (value <= 0x0fff) {
if (tolen < 3)
return (mdn_buffer_overflow);
*to++ = vlhex_string1[(value >> 8) & 0x0f];
*to++ = vlhex_string2[(value >> 4) & 0x0f];
*to++ = vlhex_string2[ value & 0x0f];
*reslen = 3;
} else {
if (tolen < 4)
return (mdn_buffer_overflow);
*to++ = vlhex_string1[(value >> 12) & 0x0f];
*to++ = vlhex_string2[(value >> 8) & 0x0f];
*to++ = vlhex_string2[(value >> 4) & 0x0f];
*to++ = vlhex_string2[ value & 0x0f];
*reslen = 4;
}
return (mdn_success);
}
static int
get_compress_mode(const unsigned short *p, size_t len) {
int non_hyphens = 0;
unsigned short same_bytes = 0;
unsigned short same_nibbles = 0;
int i;
if (len <= 0)
return plain_mode;
for (i = 0; i < len; i++) {
if (p[i] != '-') {
non_hyphens++;
if ((p[0] & 0xff00) == (p[i] & 0xff00))
same_bytes++;
else if ((p[0] & 0xf000) == (p[i] & 0xf000))
same_nibbles++;
}
}
if (non_hyphens < 2) {
/*
* The number of non '-' characters is less than 2.
*/
return plain_mode;
} else if (same_bytes == non_hyphens) {
/*
* The same most significant byte of the every non '-'
* character is the same value.
*/
return same_byte_mode;
} else if (same_nibbles == non_hyphens) {
/*
* The same most significant nibble of the every non '-'
* character is the same value.
*/
return same_nibble_mode;
} else {
/*
* Not matched above.
*/
return plain_mode;
}
/* Not reached */
}