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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1995, by Sun Microsystems, Inc.
* All rights reserved.
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <errno.h>
#include "unicode_big5p.h" /* UTF8 to Big-5 Plus mapping table */
#include "common_defs.h"
#define MSB 0x80 /* most significant bit */
#define ONEBYTE 0xff /* right most byte */
#define NON_ID_CHAR '?' /* non-identified character */
typedef struct _icv_state {
char keepc[6]; /* maximum # byte of UTF8 code */
short ustate;
int _errno; /* internal errno */
} _iconv_st;
enum _USTATE { U0, U1, U2, U3, U4, U5, U6, U7 };
static int get_big5p_by_utf(char, char, int *, unsigned long *);
static int utf8_to_big5p(int, unsigned long, char *, size_t);
static int binsearch(unsigned long, utf_big5p[], int);
/*
* Open; called from iconv_open()
*/
void *
_icv_open()
{
_iconv_st *st;
if ((st = (_iconv_st *)malloc(sizeof(_iconv_st))) == NULL) {
errno = ENOMEM;
return ((void *) -1);
}
st->ustate = U0;
st->_errno = 0;
return ((void *) st);
}
/*
* Close; called from iconv_close()
*/
void
_icv_close(_iconv_st *st)
{
if (!st)
errno = EBADF;
else
free(st);
}
/*
* Actual conversion; called from iconv()
*/
/*=========================================================
*
* State Machine for interpreting UTF8 code
*
*=========================================================
*
* 2nd byte 3rd byte 4th byte
* +----->------->------->U5------>U6--------->U7
* | |
* | 3 byte unicode |
* +----->------->-------+ |
* | | |
* ^ v |
* | 2 byte U2 ---> U3 |
* | unicode v |
* +------> U0 -------> U1 +-------->U4---+
* ^ ascii | | ^ |
* | | +-------->--------->--------+ |
* | v v
* +----<---+-----<------------<------------<------------+
*
*=========================================================*/
size_t
_icv_iconv(_iconv_st *st, char **inbuf, size_t *inbytesleft,
char **outbuf, size_t *outbytesleft)
{
char c1 = '\0', c2 = '\0';
int n, unidx;
unsigned long big5pcode;
#ifdef DEBUG
fprintf(stderr, "========== iconv(): UTF2 --> Big-5 Plus ==========\n");
#endif
if (st == NULL) {
errno = EBADF;
return ((size_t) -1);
}
if (inbuf == NULL || *inbuf == NULL) { /* Reset request. */
st->ustate = U0;
st->_errno = 0;
return ((size_t) 0);
}
st->_errno = 0; /* reset internal errno */
errno = 0; /* reset external errno */
/* a state machine for interpreting UTF8 code */
while (*inbytesleft > 0 && *outbytesleft > 0) {
uchar_t first_byte;
switch (st->ustate) {
case U0: /* assuming ASCII in the beginning */
if ((**inbuf & MSB) == 0) { /* ASCII */
**outbuf = **inbuf;
(*outbuf)++;
(*outbytesleft)--;
} else { /* Chinese character */
if ((**inbuf & 0xe0) == 0xc0) { /* 2 byte unicode 0xc2..0xdf */
/* invalid sequence if the first char is either 0xc0 or 0xc1 */
if ( number_of_bytes_in_utf8_char[((uchar_t)**inbuf)] == ICV_TYPE_ILLEGAL_CHAR )
st->_errno = errno = EILSEQ;
else {
st->ustate = U1;
st->keepc[0] = **inbuf;
}
} else if ((**inbuf & 0xf0) == 0xe0) { /* 3 byte 0xe0..0xef */
st->ustate = U2;
st->keepc[0] = **inbuf;
} else {
/* currently the 16 planes are supported */
if ( number_of_bytes_in_utf8_char[((uchar_t)**inbuf)] == ICV_TYPE_ILLEGAL_CHAR )
st->_errno = errno = EILSEQ;
else
{
st->ustate = U5;
st->keepc[0] = **inbuf;
}
}
}
break;
case U1: /* 2 byte unicode */
if ((**inbuf & 0xc0) == MSB) {
st->ustate = U4;
st->keepc[1] = **inbuf;
c1 = (st->keepc[0]&0x1c)>>2;
c2 = ((st->keepc[0]&0x03)<<6) | ((**inbuf)&0x3f);
#ifdef DEBUG
fprintf(stderr, "UTF8: %02x%02x --> ",
st->keepc[0]&ONEBYTE, st->keepc[1]&ONEBYTE);
#endif
continue; /* should not advance *inbuf */
} else {
st->_errno = errno = EILSEQ;
}
break;
case U2: /* 3 byte unicode - 2nd byte */
first_byte = st->keepc[0];
/* if the first byte is 0xed, it is illegal sequence if the second
* one is between 0xa0 and 0xbf because the surrogate section is ill-formed
*/
if (((uchar_t)**inbuf) < valid_min_2nd_byte[first_byte] ||
((uchar_t)**inbuf) > valid_max_2nd_byte[first_byte] )
st->_errno = errno = EILSEQ;
else {
st->ustate = U3;
st->keepc[1] = **inbuf;
}
break;
case U3: /* 3 byte unicode - 3rd byte */
if ((**inbuf & 0xc0) == MSB) {
st->ustate = U4;
st->keepc[2] = **inbuf;
c1 = ((st->keepc[0]&0x0f)<<4) |
((st->keepc[1]&0x3c)>>2);
c2 = ((st->keepc[1]&0x03)<<6) | ((**inbuf)&0x3f);
#ifdef DEBUG
fprintf(stderr, "UTF8: %02x%02x%02x --> ", st->keepc[0]&ONEBYTE,
st->keepc[1]&ONEBYTE, **inbuf&ONEBYTE);
#endif
continue; /* should not advance *inbuf */
} else {
st->_errno = errno = EILSEQ;
}
break;
case U4:
n = get_big5p_by_utf(c1, c2, &unidx, &big5pcode);
if ( n == -1 ) { /* unicode is either 0xfffe or 0xffff */
st->_errno = errno = EILSEQ;
break;
}
/* comment the following lines to ignore no Big5 plus characters
if (n != 0) {
st->_errno = errno = EILSEQ;
break;
}
*/
n = utf8_to_big5p(unidx, big5pcode,
*outbuf, *outbytesleft);
if (n > 0) {
(*outbuf) += n;
(*outbytesleft) -= n;
st->ustate = U0;
} else {
st->_errno = errno = E2BIG;
}
break;
case U5:
first_byte = st->keepc[0];
/* if the first byte is 0xf0, it is illegal sequence if
* the second one is between 0x80 and 0x8f
* for Four-Byte UTF: U+10000..U+10FFFF
*/
if (((uchar_t)**inbuf) < valid_min_2nd_byte[first_byte] ||
((uchar_t)**inbuf) > valid_max_2nd_byte[first_byte] )
st->_errno = errno = EILSEQ;
else
{
st->ustate = U6;
st->keepc[1] = **inbuf;
}
break;
case U6:
if ((**inbuf & 0xc0) == MSB) /* 0x80..0xbf */
{
st->ustate = U7;
st->keepc[2] = **inbuf;
}
else
st->_errno = errno = EILSEQ;
break;
case U7:
if ((**inbuf & 0xc0) == MSB) /* 0x80..0xbf */
{ /* skip it */
st->ustate = U0;
}
else
st->_errno = errno = EILSEQ;
break;
default: /* should never come here */
st->_errno = errno = EILSEQ;
st->ustate = U0; /* reset state */
break;
}
if (st->_errno) {
#ifdef DEBUG
fprintf(stderr, "!!!!!\tst->_errno = %d\tst->ustate = %d\n",
st->_errno, st->ustate);
#endif
break;
}
(*inbuf)++;
(*inbytesleft)--;
}
if (errno) return ((size_t) -1);
if (*inbytesleft == 0 && st->ustate != U0) {
errno = EINVAL;
return ((size_t) -1);
}
if (*inbytesleft > 0 && *outbytesleft == 0) {
errno = E2BIG;
return((size_t) -1);
}
return (*inbytesleft);
}
/*
* Match Big-5 Plus code by UTF8 code;
* Return: = 0 - match from Unicode to Big-5 Plus found
* = 1 - match from Unicode to Big-5 Plus NOT found
* =-1 - illegal sequence
*
* Since binary search of the UTF8 to Big-5 Plus table is necessary, might as well
* return index and Big-5 Plus code matching to the unicode.
*/
static int get_big5p_by_utf(char c1, char c2, int *unidx, unsigned long *big5pcode)
{
unsigned long unicode;
unicode = (unsigned long) ((c1 & ONEBYTE) << 8) + (c2 & ONEBYTE);
/* 0xfffe and 0xffff should not be allowed */
if ( unicode == 0xFFFE || unicode == 0xFFFF ) return -1;
*unidx = binsearch(unicode, utf_big5p_tab, MAX_BIG5P_NUM);
if ((*unidx) >= 0)
*big5pcode = utf_big5p_tab[*unidx].big5pcode;
else
return(1); /* match from UTF8 to Big-5 Plus not found */
#ifdef DEBUG
fprintf(stderr, "Unicode=%04x, idx=%5d, Big-5 Plus=%x ", unicode, *unidx, *big5pcode);
#endif
return(0);
}
/*
* ISO/IEC 10646 (Unicode) --> Big-5 Plus
* Unicode --> UTF8 (FSS-UTF)
* (File System Safe Universal Character Set Transformation Format)
* Return: > 0 - converted with enough space in output buffer
* = 0 - no space in outbuf
*/
static int utf8_to_big5p(int unidx, unsigned long big5pcode, char *buf, size_t buflen)
{
unsigned long val; /* Big-5 Plus value */
char c1, c2, big5p_str[3];
if (buflen < 2) {
errno = E2BIG;
return(0);
}
if (unidx < 0) { /* no match from UTF8 to Big-5 Plus */
*buf = *(buf+1) = NON_ID_CHAR;
} else {
val = big5pcode & 0xffff;
c1 = (char) ((val & 0xff00) >> 8);
c2 = (char) (val & 0xff);
*buf = big5p_str[0] = c1;
*(buf+1) = big5p_str[1] = c2;
big5p_str[2] = NULL;
}
#ifdef DEBUG
fprintf(stderr, "\t->%x %x<-\n", *buf, *(buf+1));
#endif
return(2);
}
/* binsearch: find x in v[0] <= v[1] <= ... <= v[n-1] */
static int binsearch(unsigned long x, utf_big5p v[], int n)
{
int low, high, mid;
low = 0;
high = n - 1;
while (low <= high) {
mid = (low + high) / 2;
if (x < v[mid].unicode)
high = mid - 1;
else if (x > v[mid].unicode)
low = mid + 1;
else /* found match */
return mid;
}
return (-1); /* no match */
}