chartype.c

/*      $NetBSD: chartype.c,v 1.10 2011/08/16 16:25:15 christos Exp $   */

/*-
 * Copyright (c) 2009 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 THE FOUNDATION OR CONTRIBUTORS
 * 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 DAMAGE.
 */

/*
 * chartype.c: character classification and meta information
 */
#include "config.h"
#if !defined(lint) && !defined(SCCSID)
#endif /* not lint && not SCCSID */
#include "el.h"
#include <stdlib.h>

#define CT_BUFSIZ ((size_t)1024)

#ifdef WIDECHAR
protected void
ct_conv_buff_resize(ct_buffer_t *conv, size_t mincsize, size_t minwsize)
{
        void *p;
        if (mincsize > conv->csize) {
                conv->csize = mincsize;
                p = el_realloc(conv->cbuff, conv->csize * sizeof(*conv->cbuff));
                if (p == NULL) {
                        conv->csize = 0;
                        el_free(conv->cbuff);
                        conv->cbuff = NULL;
                } else 
                        conv->cbuff = p;
        }

        if (minwsize > conv->wsize) {
                conv->wsize = minwsize;
                p = el_realloc(conv->wbuff, conv->wsize * sizeof(*conv->wbuff));
                if (p == NULL) {
                        conv->wsize = 0;
                        el_free(conv->wbuff);
                        conv->wbuff = NULL;
                } else
                        conv->wbuff = p;
        }
}


public char *
ct_encode_string(const Char *s, ct_buffer_t *conv)
{
        char *dst;
        ssize_t used = 0;
        mbstate_t state;

        memset(&state, 0, sizeof(mbstate_t));

        if (!s)
                return NULL;
        if (!conv->cbuff)
                ct_conv_buff_resize(conv, CT_BUFSIZ, (size_t)0);
        if (!conv->cbuff)
                return NULL;

        dst = conv->cbuff;
        while (*s) {
                used = (ssize_t)(conv->csize - (size_t)(dst - conv->cbuff));
                if (used < 5) {
                        used = dst - conv->cbuff;
                        ct_conv_buff_resize(conv, conv->csize + CT_BUFSIZ,
                            (size_t)0);
                        if (!conv->cbuff)
                                return NULL;
                        dst = conv->cbuff + used;
                }
                used = ct_encode_char(dst, (size_t)5, *s, &state);
                if (used == -1) /* failed to encode, need more buffer space */
                        abort();
                ++s;
                dst += used;
        }
        *dst = '\0';
        return conv->cbuff;
}

public Char *
ct_decode_string(const char *s, ct_buffer_t *conv)
{
        size_t len = 0;

        if (!s)
                return NULL;
        if (!conv->wbuff)
                ct_conv_buff_resize(conv, (size_t)0, CT_BUFSIZ);
        if (!conv->wbuff)
                return NULL;

        len = ct_mbstowcs(NULL, s, (size_t)0);
        if (len == (size_t)-1)
                return NULL;
        if (len > conv->wsize)
                ct_conv_buff_resize(conv, (size_t)0, len + 1);
        if (!conv->wbuff)
                return NULL;
        ct_mbstowcs(conv->wbuff, s, conv->wsize);
        return conv->wbuff;
}


protected Char **
ct_decode_argv(int argc, const char *argv[], ct_buffer_t *conv)
{
        size_t bufspace;
        int i;
        Char *p;
        Char **wargv;
        ssize_t bytes;
        mbstate_t state;

        /* Make sure we have enough space in the conversion buffer to store all
         * the argv strings. */
        for (i = 0, bufspace = 0; i < argc; ++i)
                bufspace += argv[i] ? strlen(argv[i]) + 1 : 0;
        ct_conv_buff_resize(conv, (size_t)0, bufspace);
        if (!conv->wsize)
                return NULL;

        wargv = el_malloc((size_t)argc * sizeof(*wargv));

        for (i = 0, p = conv->wbuff; i < argc; ++i) {
                if (!argv[i]) {   /* don't pass null pointers to mbsrtowcs */
                        wargv[i] = NULL;
                        continue;
                } else {
                        wargv[i] = p;
                        memset(&state, 0, sizeof(mbstate_t));
                        bytes = (ssize_t)mbsrtowcs(p, argv + i, bufspace, &state);
                }
                if (bytes == -1) {
                        el_free(wargv);
                        return NULL;
                } else
                        bytes++;  /* include '\0' in the count */
                bufspace -= (size_t)bytes;
                p += bytes;
        }

        return wargv;
}


protected size_t
ct_enc_width(Char c)
{
        /* UTF-8 encoding specific values */
        if (c < 0x80)
                return 1;
        else if (c < 0x0800)
                return 2;
        else if (c < 0x10000)
                return 3;
        else if (c < 0x110000)
                return 4;
        else
                return 0; /* not a valid codepoint */
}

protected ssize_t
ct_encode_char(char *dst, size_t len, Char c, mbstate_t *state)
{
        ssize_t l = 0;

        if (len < ct_enc_width(c))
                return -1;

        l = wcrtomb(dst, c, state);

        if (l < 0) {
                memset (state, 0, sizeof (mbstate_t));
                l = 0;
        }
        return l;
}
#endif

protected const Char *
ct_visual_string(const Char *s)
{
        static Char *buff = NULL;
        static size_t buffsize = 0;
        void *p;
        Char *dst;
        ssize_t used = 0;

        if (!s)
                return NULL;
        if (!buff) {
            buffsize = CT_BUFSIZ;
            buff = el_malloc(buffsize * sizeof(*buff));
        }
        dst = buff;
        while (*s) {
                used = ct_visual_char(dst, buffsize - (size_t)(dst - buff), *s);
                if (used == -1) { /* failed to encode, need more buffer space */
                        used = dst - buff;
                        buffsize += CT_BUFSIZ;
                        p = el_realloc(buff, buffsize * sizeof(*buff));
                        if (p == NULL)
                                goto out;
                        buff = p;
                        dst = buff + used;
                        /* don't increment s here - we want to retry it! */
                }
                else
                    ++s;
                dst += used;
        }
        if (dst >= (buff + buffsize)) { /* sigh */
                buffsize += 1;
                p = el_realloc(buff, buffsize * sizeof(*buff));
                if (p == NULL)
                        goto out;
                buff = p;
                dst = buff + buffsize - 1;
        }
        *dst = 0;
        return buff;
out:
        el_free(buff);
        buffsize = 0;
        return NULL;
}


protected int
ct_visual_width(Char c)
{
        int t = ct_chr_class(c);
        switch (t) {
        case CHTYPE_ASCIICTL:
                return 2; /* ^@ ^? etc. */
        case CHTYPE_TAB:
                return 1; /* Hmm, this really need to be handled outside! */
        case CHTYPE_NL:
                return 0; /* Should this be 1 instead? */
#ifdef WIDECHAR
        case CHTYPE_PRINT:
                return wcwidth(c);
        case CHTYPE_NONPRINT:
                if (c > 0xffff) /* prefer standard 4-byte display over 5-byte */
                        return 8; /* \U+12345 */
                else
                        return 7; /* \U+1234 */
#else
        case CHTYPE_PRINT:
                return 1;
        case CHTYPE_NONPRINT:
                return 4; /* \123 */
#endif
        default:
                return 0; /* should not happen */
        }
}


protected ssize_t
ct_visual_char(Char *dst, size_t len, Char c)
{
        int t = ct_chr_class(c);
        switch (t) {
        case CHTYPE_TAB:
        case CHTYPE_NL:
        case CHTYPE_ASCIICTL:
                if (len < 2)
                        return -1;   /* insufficient space */
                *dst++ = '^';
                if (c == '\177')
                        *dst = '?'; /* DEL -> ^? */
                else
                        *dst = c | 0100;    /* uncontrolify it */
                return 2;
        case CHTYPE_PRINT:
                if (len < 1)
                        return -1;  /* insufficient space */
                *dst = c;
                return 1;
        case CHTYPE_NONPRINT:
                /* we only use single-width glyphs for display,
                 * so this is right */
                if ((ssize_t)len < ct_visual_width(c))
                        return -1;   /* insufficient space */
#ifdef WIDECHAR
                *dst++ = '\\';
                *dst++ = 'U';
                *dst++ = '+';
#define tohexdigit(v) "0123456789ABCDEF"[v]
                if (c > 0xffff) /* prefer standard 4-byte display over 5-byte */
                        *dst++ = tohexdigit(((unsigned int) c >> 16) & 0xf);
                *dst++ = tohexdigit(((unsigned int) c >> 12) & 0xf);
                *dst++ = tohexdigit(((unsigned int) c >>  8) & 0xf);
                *dst++ = tohexdigit(((unsigned int) c >>  4) & 0xf);
                *dst   = tohexdigit(((unsigned int) c      ) & 0xf);
                return c > 0xffff ? 8 : 7;
#else
                *dst++ = '\\';
#define tooctaldigit(v) ((v) + '0')
                *dst++ = tooctaldigit(((unsigned int) c >> 6) & 0x7);
                *dst++ = tooctaldigit(((unsigned int) c >> 3) & 0x7);
                *dst++ = tooctaldigit(((unsigned int) c     ) & 0x7);
#endif
                /*FALLTHROUGH*/
        /* these two should be handled outside this function */
        default:            /* we should never hit the default */
                return 0;
        }
}




protected int
ct_chr_class(Char c)
{
        if (c == '\t')
                return CHTYPE_TAB;
        else if (c == '\n')
                return CHTYPE_NL;
        else if (IsASCII(c) && Iscntrl(c))
                return CHTYPE_ASCIICTL;
        else if (Isprint(c))
                return CHTYPE_PRINT;
        else
                return CHTYPE_NONPRINT;
}