mbfilter_ucs4.c

Go to the documentation of this file.

/*
 * "streamable kanji code filter and converter"
 * Copyright (c) 1998-2002 HappySize, Inc. All rights reserved.
 *
 * LICENSE NOTICES
 *
 * This file is part of "streamable kanji code filter and converter",
 * which is distributed under the terms of GNU Lesser General Public
 * License (version 2) as published by the Free Software Foundation.
 *
 * This software 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 "streamable kanji code filter and converter";
 * if not, write to the Free Software Foundation, Inc., 59 Temple Place,
 * Suite 330, Boston, MA  02111-1307  USA
 *
 * The author of this file:
 *
 */
/*
 * The source code included in this file was separated from mbfilter.c
 * by moriyoshi koizumi <moriyoshi@php.net> on 4 dec 2002.
 *
 */
 
#include "mbfilter.h"
#include "mbfilter_ucs4.h"
 
static size_t mb_ucs4_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state);
static size_t mb_ucs4be_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state);
static void mb_wchar_to_ucs4be(uint32_t *in, size_t len, mb_convert_buf *buf, bool end);
static size_t mb_ucs4le_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state);
static void mb_wchar_to_ucs4le(uint32_t *in, size_t len, mb_convert_buf *buf, bool end);
 
static const char *mbfl_encoding_ucs4_aliases[] = {"ISO-10646-UCS-4", "UCS4", NULL};
 
/* This library historically had encodings called 'byte4be' and 'byte4le'
 * which were almost identical to UCS-4
 * Maintain minimal support by aliasing to UCS-4 */
static const char *mbfl_encoding_ucs4be_aliases[] = {"byte4be", NULL};
static const char *mbfl_encoding_ucs4le_aliases[] = {"byte4le", NULL};
 
static int mbfl_filt_conv_ucs4_wchar_flush(mbfl_convert_filter *filter);
 
const mbfl_encoding mbfl_encoding_ucs4 = {
    mbfl_no_encoding_ucs4,
    "UCS-4",
    "UCS-4",
    mbfl_encoding_ucs4_aliases,
    NULL,
    MBFL_ENCTYPE_WCS4,
    &vtbl_ucs4_wchar,
    &vtbl_wchar_ucs4,
    mb_ucs4_to_wchar,
    mb_wchar_to_ucs4be,
    NULL,
    NULL,
};
 
const mbfl_encoding mbfl_encoding_ucs4be = {
    mbfl_no_encoding_ucs4be,
    "UCS-4BE",
    "UCS-4BE",
    mbfl_encoding_ucs4be_aliases,
    NULL,
    MBFL_ENCTYPE_WCS4,
    &vtbl_ucs4be_wchar,
    &vtbl_wchar_ucs4be,
    mb_ucs4be_to_wchar,
    mb_wchar_to_ucs4be,
    NULL,
    NULL,
};
 
const mbfl_encoding mbfl_encoding_ucs4le = {
    mbfl_no_encoding_ucs4le,
    "UCS-4LE",
    "UCS-4LE",
    mbfl_encoding_ucs4le_aliases,
    NULL,
    MBFL_ENCTYPE_WCS4,
    &vtbl_ucs4le_wchar,
    &vtbl_wchar_ucs4le,
    mb_ucs4le_to_wchar,
    mb_wchar_to_ucs4le,
    NULL,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_ucs4_wchar = {
    mbfl_no_encoding_ucs4,
    mbfl_no_encoding_wchar,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_ucs4_wchar,
    mbfl_filt_conv_ucs4_wchar_flush,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_wchar_ucs4 = {
    mbfl_no_encoding_wchar,
    mbfl_no_encoding_ucs4,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_wchar_ucs4be,
    mbfl_filt_conv_common_flush,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_ucs4be_wchar = {
    mbfl_no_encoding_ucs4be,
    mbfl_no_encoding_wchar,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_ucs4be_wchar,
    mbfl_filt_conv_ucs4_wchar_flush,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_wchar_ucs4be = {
    mbfl_no_encoding_wchar,
    mbfl_no_encoding_ucs4be,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_wchar_ucs4be,
    mbfl_filt_conv_common_flush,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_ucs4le_wchar = {
    mbfl_no_encoding_ucs4le,
    mbfl_no_encoding_wchar,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_ucs4le_wchar,
    mbfl_filt_conv_ucs4_wchar_flush,
    NULL,
};
 
const struct mbfl_convert_vtbl vtbl_wchar_ucs4le = {
    mbfl_no_encoding_wchar,
    mbfl_no_encoding_ucs4le,
    mbfl_filt_conv_common_ctor,
    NULL,
    mbfl_filt_conv_wchar_ucs4le,
    mbfl_filt_conv_common_flush,
    NULL,
};
 
 
#define CK(statement)   do { if ((statement) < 0) return (-1); } while (0)
 
/*
 * UCS-4 => wchar
 */
int mbfl_filt_conv_ucs4_wchar(int c, mbfl_convert_filter *filter)
{
    int n, endian;
 
    endian = filter->status & 0xff00;
    switch (filter->status & 0xff) {
    case 0:
        if (endian) {
            n = c & 0xff;
        } else {
            n = (c & 0xffu) << 24;
        }
        filter->cache = n;
        filter->status++;
        break;
    case 1:
        if (endian) {
            n = (c & 0xff) << 8;
        } else {
            n = (c & 0xff) << 16;
        }
        filter->cache |= n;
        filter->status++;
        break;
    case 2:
        if (endian) {
            n = (c & 0xff) << 16;
        } else {
            n = (c & 0xff) << 8;
        }
        filter->cache |= n;
        filter->status++;
        break;
    default:
        if (endian) {
            n = (c & 0xffu) << 24;
        } else {
            n = c & 0xff;
        }
        n |= filter->cache;
        filter->status &= ~0xff;
        if ((n & 0xffff) == 0 && ((n >> 16) & 0xffff) == 0xfffe) {
            if (endian) {
                filter->status = 0;       /* big-endian */
            } else {
                filter->status = 0x100;       /* little-endian */
            }
        } else if (n != 0xfeff) {
            CK((*filter->output_function)(n, filter->data));
        }
        break;
    }
 
    return 0;
}
 
/*
 * UCS-4BE => wchar
 */
int mbfl_filt_conv_ucs4be_wchar(int c, mbfl_convert_filter *filter)
{
    int n;
 
    if (filter->status == 0) {
        filter->status = 1;
        n = (c & 0xffu) << 24;
        filter->cache = n;
    } else if (filter->status == 1) {
        filter->status = 2;
        n = (c & 0xff) << 16;
        filter->cache |= n;
    } else if (filter->status == 2) {
        filter->status = 3;
        n = (c & 0xff) << 8;
        filter->cache |= n;
    } else {
        filter->status = 0;
        n = (c & 0xff) | filter->cache;
        CK((*filter->output_function)(n, filter->data));
    }
    return 0;
}
 
/*
 * wchar => UCS-4BE
 */
int mbfl_filt_conv_wchar_ucs4be(int c, mbfl_convert_filter *filter)
{
    if (c != MBFL_BAD_INPUT) {
        CK((*filter->output_function)((c >> 24) & 0xff, filter->data));
        CK((*filter->output_function)((c >> 16) & 0xff, filter->data));
        CK((*filter->output_function)((c >> 8) & 0xff, filter->data));
        CK((*filter->output_function)(c & 0xff, filter->data));
    } else {
        CK(mbfl_filt_conv_illegal_output(c, filter));
    }
 
    return 0;
}
 
/*
 * UCS-4LE => wchar
 */
int mbfl_filt_conv_ucs4le_wchar(int c, mbfl_convert_filter *filter)
{
    int n;
 
    if (filter->status == 0) {
        filter->status = 1;
        n = (c & 0xff);
        filter->cache = n;
    } else if (filter->status == 1) {
        filter->status = 2;
        n = (c & 0xff) << 8;
        filter->cache |= n;
    } else if (filter->status == 2) {
        filter->status = 3;
        n = (c & 0xff) << 16;
        filter->cache |= n;
    } else {
        filter->status = 0;
        n = ((c & 0xffu) << 24) | filter->cache;
        CK((*filter->output_function)(n, filter->data));
    }
    return 0;
}
 
/*
 * wchar => UCS-4LE
 */
int mbfl_filt_conv_wchar_ucs4le(int c, mbfl_convert_filter *filter)
{
    if (c != MBFL_BAD_INPUT) {
        CK((*filter->output_function)(c & 0xff, filter->data));
        CK((*filter->output_function)((c >> 8) & 0xff, filter->data));
        CK((*filter->output_function)((c >> 16) & 0xff, filter->data));
        CK((*filter->output_function)((c >> 24) & 0xff, filter->data));
    } else {
        CK(mbfl_filt_conv_illegal_output(c, filter));
    }
 
    return 0;
}
 
static int mbfl_filt_conv_ucs4_wchar_flush(mbfl_convert_filter *filter)
{
    if (filter->status & 0xF) {
        /* Input string was truncated */
        CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
    }
    filter->status = 0;
 
    if (filter->flush_function) {
        (*filter->flush_function)(filter->data);
    }
 
    return 0;
}
 
#define DETECTED_BE 1
#define DETECTED_LE 2
 
static size_t mb_ucs4_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state)
{
    if (*state == DETECTED_BE) {
        return mb_ucs4be_to_wchar(in, in_len, buf, bufsize, NULL);
    } else if (*state == DETECTED_LE) {
        return mb_ucs4le_to_wchar(in, in_len, buf, bufsize, NULL);
    } else if (*in_len >= 4) {
        unsigned char *p = *in;
        uint32_t c1 = *p++;
        uint32_t c2 = *p++;
        uint32_t c3 = *p++;
        uint32_t c4 = *p++;
        uint32_t w = (c1 << 24) | (c2 << 16) | (c3 << 8) | c4;
 
        if (w == 0xFFFE0000) {
            /* Little-endian BOM */
            *in = p;
            *in_len -= 4;
            *state = DETECTED_LE;
            return mb_ucs4le_to_wchar(in, in_len, buf, bufsize, NULL);
        } else if (w == 0xFEFF) {
            /* Big-endian BOM; don't send it to output */
            *in = p;
            *in_len -= 4;
        }
    }
 
    *state = DETECTED_BE;
    return mb_ucs4be_to_wchar(in, in_len, buf, bufsize, NULL);
}
 
static size_t mb_ucs4be_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state)
{
    unsigned char *p = *in, *e = p + (*in_len & ~3);
    uint32_t *out = buf, *limit = buf + bufsize;
 
    while (p < e && out < limit) {
        uint32_t c1 = *p++;
        uint32_t c2 = *p++;
        uint32_t c3 = *p++;
        uint32_t c4 = *p++;
        uint32_t w = (c1 << 24) | (c2 << 16) | (c3 << 8) | c4;
        *out++ = w;
    }
 
    if (p == e && (*in_len & 0x3) && out < limit) {
        /* There are 1-3 trailing bytes, which shouldn't be there */
        *out++ = MBFL_BAD_INPUT;
        p = *in + *in_len;
    }
 
    *in_len -= (p - *in);
    *in = p;
    return out - buf;
}
 
static void mb_wchar_to_ucs4be(uint32_t *in, size_t len, mb_convert_buf *buf, bool end)
{
    unsigned char *out, *limit;
    MB_CONVERT_BUF_LOAD(buf, out, limit);
    MB_CONVERT_BUF_ENSURE(buf, out, limit, len * 4);
 
    while (len--) {
        uint32_t w = *in++;
        if (w != MBFL_BAD_INPUT) {
            out = mb_convert_buf_add4(out, (w >> 24) & 0xFF, (w >> 16) & 0xFF, (w >> 8) & 0xFF, w & 0xFF);
        } else {
            MB_CONVERT_ERROR(buf, out, limit, w, mb_wchar_to_ucs4be);
            MB_CONVERT_BUF_ENSURE(buf, out, limit, len * 4);
        }
    }
 
    MB_CONVERT_BUF_STORE(buf, out, limit);
}
 
static size_t mb_ucs4le_to_wchar(unsigned char **in, size_t *in_len, uint32_t *buf, size_t bufsize, unsigned int *state)
{
    unsigned char *p = *in, *e = p + (*in_len & ~3);
    uint32_t *out = buf, *limit = buf + bufsize;
 
    while (p < e && out < limit) {
        uint32_t c1 = *p++;
        uint32_t c2 = *p++;
        uint32_t c3 = *p++;
        uint32_t c4 = *p++;
        uint32_t w = (c4 << 24) | (c3 << 16) | (c2 << 8) | c1;
        *out++ = w;
    }
 
    if (p == e && (*in_len & 0x3) && out < limit) {
        /* There are 1-3 trailing bytes, which shouldn't be there */
        *out++ = MBFL_BAD_INPUT;
        p = *in + *in_len;
    }
 
    *in_len -= (p - *in);
    *in = p;
    return out - buf;
}
 
static void mb_wchar_to_ucs4le(uint32_t *in, size_t len, mb_convert_buf *buf, bool end)
{
    unsigned char *out, *limit;
    MB_CONVERT_BUF_LOAD(buf, out, limit);
    MB_CONVERT_BUF_ENSURE(buf, out, limit, len * 4);
 
    while (len--) {
        uint32_t w = *in++;
        if (w != MBFL_BAD_INPUT) {
            out = mb_convert_buf_add4(out, w & 0xFF, (w >> 8) & 0xFF, (w >> 16) & 0xFF, (w >> 24) & 0xFF);
        } else {
            MB_CONVERT_ERROR(buf, out, limit, w, mb_wchar_to_ucs4le);
            MB_CONVERT_BUF_ENSURE(buf, out, limit, len * 4);
        }
    }
 
    MB_CONVERT_BUF_STORE(buf, out, limit);
}