Add an error check for correct formatting in Deflate uncompressed

[sgt/halibut] / bk_whlp.c

/*
 * Windows Help backend for Halibut
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <assert.h>

#include "halibut.h"
#include "winhelp.h"

struct bk_whlp_state {
    WHLP h;
    indexdata *idx;
    keywordlist *keywords;
    WHLP_TOPIC curr_topic;
    int charset;
    charset_state cstate;
    FILE *cntfp;
    int cnt_last_level, cnt_workaround;
};

typedef struct {
    int charset;
    wchar_t *bullet, *lquote, *rquote, *titlepage, *sectsuffix, *listsuffix;
    wchar_t *contents_text;
    char *filename;
} whlpconf;

/*
 * Indexes of fonts in our standard font descriptor set.
 */
enum {
    FONT_NORMAL,
    FONT_EMPH,
    FONT_CODE,
    FONT_ITAL_CODE,
    FONT_BOLD_CODE,
    FONT_TITLE,
    FONT_TITLE_EMPH,
    FONT_TITLE_CODE,
    FONT_RULE
};

static void whlp_rdaddwc(rdstringc *rs, word *text, whlpconf *conf,
                         charset_state *state);
static void whlp_rdadds(rdstringc *rs, const wchar_t *text, whlpconf *conf,
                        charset_state *state);
static void whlp_mkparagraph(struct bk_whlp_state *state,
                             int font, word *text, int subsidiary,
                             whlpconf *conf);
static void whlp_navmenu(struct bk_whlp_state *state, paragraph *p,
                         whlpconf *conf);
static void whlp_contents_write(struct bk_whlp_state *state,
                                int level, char *text, WHLP_TOPIC topic);
static void whlp_wtext(struct bk_whlp_state *state, const wchar_t *text);
    
paragraph *whlp_config_filename(char *filename)
{
    return cmdline_cfg_simple("winhelp-filename", filename, NULL);
}

static whlpconf whlp_configure(paragraph *source) {
    paragraph *p;
    whlpconf ret;

    /*
     * Defaults.
     */
    ret.charset = CS_CP1252;
    ret.bullet = L"\x2022\0-\0\0";
    ret.lquote = L"\x2018\0\x2019\0\"\0\"\0\0";
    ret.rquote = uadv(ret.lquote);
    ret.filename = dupstr("output.hlp");
    ret.titlepage = L"Title page";
    ret.contents_text = L"Contents";
    ret.sectsuffix = L": ";
    ret.listsuffix = L".";

    /*
     * Two-pass configuration so that we can pick up global config
     * (e.g. `quotes') before having it overridden by specific
     * config (`win-quotes'), irrespective of the order in which
     * they occur.
     */
    for (p = source; p; p = p->next) {
        if (p->type == para_Config) {
            if (!ustricmp(p->keyword, L"quotes")) {
                if (*uadv(p->keyword) && *uadv(uadv(p->keyword))) {
                    ret.lquote = uadv(p->keyword);
                    ret.rquote = uadv(ret.lquote);
                }
            }
        }
    }

    for (p = source; p; p = p->next) {
        p->private_data = NULL;
        if (p->type == para_Config) {
            /*
             * In principle we should support a `winhelp-charset'
             * here. We don't, because my WinHelp output code
             * doesn't know how to change character set. Once I
             * find out, I'll support it.
             */
            if (p->parent && !ustricmp(p->keyword, L"winhelp-topic")) {
                /* Store the topic name in the private_data field of the
                 * containing section. */
                p->parent->private_data = uadv(p->keyword);
            } else if (!ustricmp(p->keyword, L"winhelp-filename")) {
                sfree(ret.filename);
                ret.filename = dupstr(adv(p->origkeyword));
            } else if (!ustricmp(p->keyword, L"winhelp-bullet")) {
                ret.bullet = uadv(p->keyword);
            } else if (!ustricmp(p->keyword, L"winhelp-section-suffix")) {
                ret.sectsuffix = uadv(p->keyword);
            } else if (!ustricmp(p->keyword, L"winhelp-list-suffix")) {
                ret.listsuffix = uadv(p->keyword);
            } else if (!ustricmp(p->keyword, L"winhelp-contents-titlepage")) {
                ret.titlepage = uadv(p->keyword);
            } else if (!ustricmp(p->keyword, L"winhelp-quotes")) {
                if (*uadv(p->keyword) && *uadv(uadv(p->keyword))) {
                    ret.lquote = uadv(p->keyword);
                    ret.rquote = uadv(ret.lquote);
                }
            } else if (!ustricmp(p->keyword, L"contents")) {
                ret.contents_text = uadv(p->keyword);
            }
        }
    }

    /*
     * Now process fallbacks on quote characters and bullets.
     */
    while (*uadv(ret.rquote) && *uadv(uadv(ret.rquote)) &&
           (!cvt_ok(ret.charset, ret.lquote) ||
            !cvt_ok(ret.charset, ret.rquote))) {
        ret.lquote = uadv(ret.rquote);
        ret.rquote = uadv(ret.lquote);
    }

    while (*ret.bullet && *uadv(ret.bullet) &&
           !cvt_ok(ret.charset, ret.bullet))
        ret.bullet = uadv(ret.bullet);

    return ret;
}

void whlp_backend(paragraph *sourceform, keywordlist *keywords,
                  indexdata *idx, void *unused) {
    WHLP h;
    char *cntname;
    paragraph *p, *lastsect;
    struct bk_whlp_state state;
    WHLP_TOPIC contents_topic;
    int i;
    int nesting;
    indexentry *ie;
    int done_contents_topic = FALSE;
    whlpconf conf;

    IGNORE(unused);

    h = state.h = whlp_new();
    state.keywords = keywords;
    state.idx = idx;

    whlp_start_macro(h, "CB(\"btn_about\",\"&About\",\"About()\")");
    whlp_start_macro(h, "CB(\"btn_up\",\"&Up\",\"Contents()\")");
    whlp_start_macro(h, "BrowseButtons()");

    whlp_create_font(h, "Times New Roman", WHLP_FONTFAM_SERIF, 24,
                     0, 0, 0, 0);
    whlp_create_font(h, "Times New Roman", WHLP_FONTFAM_SERIF, 24,
                     WHLP_FONT_ITALIC, 0, 0, 0);
    whlp_create_font(h, "Courier New", WHLP_FONTFAM_FIXED, 24,
                     0, 0, 0, 0);
    whlp_create_font(h, "Courier New", WHLP_FONTFAM_FIXED, 24,
                     WHLP_FONT_ITALIC, 0, 0, 0);
    whlp_create_font(h, "Courier New", WHLP_FONTFAM_FIXED, 24,
                     WHLP_FONT_BOLD, 0, 0, 0);
    whlp_create_font(h, "Arial", WHLP_FONTFAM_SERIF, 30,
                     WHLP_FONT_BOLD, 0, 0, 0);
    whlp_create_font(h, "Arial", WHLP_FONTFAM_SERIF, 30,
                     WHLP_FONT_BOLD|WHLP_FONT_ITALIC, 0, 0, 0);
    whlp_create_font(h, "Courier New", WHLP_FONTFAM_FIXED, 30,
                     WHLP_FONT_BOLD, 0, 0, 0);
    whlp_create_font(h, "Courier New", WHLP_FONTFAM_SANS, 18,
                     WHLP_FONT_STRIKEOUT, 0, 0, 0);

    conf = whlp_configure(sourceform);

    state.charset = conf.charset;

    /*
     * Ensure the output file name has a .hlp extension. This is
     * required since we must create the .cnt file in parallel with
     * it.
     */
    {
        int len = strlen(conf.filename);
        if (len < 4 || conf.filename[len-4] != '.' ||
            tolower(conf.filename[len-3] != 'h') ||
            tolower(conf.filename[len-2] != 'l') ||
            tolower(conf.filename[len-1] != 'p')) {
            char *newf;
            newf = snewn(len + 5, char);
            sprintf(newf, "%s.hlp", conf.filename);
            sfree(conf.filename);
            conf.filename = newf;
            len = strlen(newf);
        }
        cntname = snewn(len+1, char);
        sprintf(cntname, "%.*s.cnt", len-4, conf.filename);
    }

    state.cntfp = fopen(cntname, "wb");
    if (!state.cntfp) {
        error(err_cantopenw, cntname);
        return;
    }
    state.cnt_last_level = -1; state.cnt_workaround = 0;

    /*
     * Loop over the source form registering WHLP_TOPICs for
     * everything.
     */

    contents_topic = whlp_register_topic(h, "Top", NULL);
    whlp_primary_topic(h, contents_topic);
    for (p = sourceform; p; p = p->next) {
        if (p->type == para_Chapter ||
            p->type == para_Appendix ||
            p->type == para_UnnumberedChapter ||
            p->type == para_Heading ||
            p->type == para_Subsect) {

            rdstringc rs = { 0, 0, NULL };
            char *errstr;

            whlp_rdadds(&rs, (wchar_t *)p->private_data, &conf, NULL);

            p->private_data = whlp_register_topic(h, rs.text, &errstr);
            if (!p->private_data) {
                p->private_data = whlp_register_topic(h, NULL, NULL);
                error(err_winhelp_ctxclash, &p->fpos, rs.text, errstr);
            }
            sfree(rs.text);
        }
    }

    /*
     * Loop over the index entries, preparing final text forms for
     * each one.
     */
    {
        indexentry *ie_prev = NULL;
        int nspaces = 1;

        for (i = 0; (ie = index234(idx->entries, i)) != NULL; i++) {
            rdstringc rs = {0, 0, NULL};
            charset_state state = CHARSET_INIT_STATE;
            whlp_rdaddwc(&rs, ie->text, &conf, &state);

            if (ie_prev) {
                /*
                 * It appears that Windows Help's index mechanism
                 * is inherently case-insensitive. Therefore, if two
                 * adjacent index terms compare equal apart from
                 * case, I'm going to append nonbreaking spaces to
                 * the end of the second one so that Windows will
                 * treat them as distinct.
                 * 
                 * This is nasty because we're depending on our
                 * case-insensitive comparison having the same
                 * semantics as the Windows one :-/ but I see no
                 * alternative.
                 */
                wchar_t *a, *b;

                a = ufroma_dup((char *)ie_prev->backend_data, conf.charset);
                b = ufroma_dup(rs.text, conf.charset);
                if (!ustricmp(a, b)) {
                    int j;
                    for (j = 0; j < nspaces; j++)
                        whlp_rdadds(&rs, L"\xA0", &conf, &state);
                    /*
                     * Add one to nspaces, so that if another term
                     * appears which is equivalent to the previous
                     * two it'll acquire one more space.
                     */
                    nspaces++;
                } else
                    nspaces = 1;
                sfree(a);
                sfree(b);
            }

            whlp_rdadds(&rs, NULL, &conf, &state);

            ie->backend_data = rs.text;

            /*
             * Only move ie_prev on if nspaces==1 (since when we
             * have three or more adjacent terms differing only in
             * case, we will want to compare with the _first_ of
             * them because that won't have had any extra spaces
             * added on which will foul up the comparison).
             */
            if (nspaces == 1)
                ie_prev = ie;
        }
    }

    whlp_prepare(h);

    /* ------------------------------------------------------------------
     * Begin the contents page.
     */
    {
        rdstringc rs = {0, 0, NULL};
        whlp_rdadds(&rs, conf.contents_text, &conf, NULL);
        whlp_begin_topic(h, contents_topic, rs.text, "DB(\"btn_up\")", NULL);
        state.curr_topic = contents_topic;
        sfree(rs.text);
    }

    /*
     * The manual title goes in the non-scroll region, and also
     * goes into the system title slot.
     */
    {
        rdstringc rs = {0, 0, NULL};
        for (p = sourceform; p; p = p->next) {
            if (p->type == para_Title) {
                whlp_begin_para(h, WHLP_PARA_NONSCROLL);
                state.cstate = charset_init_state;
                whlp_mkparagraph(&state, FONT_TITLE, p->words, FALSE, &conf);
                whlp_wtext(&state, NULL);
                whlp_end_para(h);
                whlp_rdaddwc(&rs, p->words, &conf, NULL);
            }
        }
        if (rs.text) {
            whlp_title(h, rs.text);
            fprintf(state.cntfp, ":Title %s\r\n", rs.text);
            sfree(rs.text);
        }
        {
            rdstringc rs2 = {0,0,NULL};
            whlp_rdadds(&rs2, conf.titlepage, &conf, NULL);
            whlp_contents_write(&state, 1, rs2.text, contents_topic);
            sfree(rs2.text);
        }
    }

    /*
     * Put the copyright into the system section.
     */
    {
        rdstringc rs = {0, 0, NULL};
        for (p = sourceform; p; p = p->next) {
            if (p->type == para_Copyright)
                whlp_rdaddwc(&rs, p->words, &conf, NULL);
        }
        if (rs.text) {
            whlp_copyright(h, rs.text);
            sfree(rs.text);
        }
    }

    lastsect = NULL;

    /* ------------------------------------------------------------------
     * Now we've done the contents page, we're ready to go through
     * and do the main manual text. Ooh.
     */
    nesting = 0;
    for (p = sourceform; p; p = p->next) switch (p->type) {
        /*
         * Things we ignore because we've already processed them or
         * aren't going to touch them in this pass.
         */
      case para_IM:
      case para_BR:
      case para_Biblio:                /* only touch BiblioCited */
      case para_VersionID:
      case para_NoCite:
      case para_Title:
        break;

      case para_LcontPush:
      case para_QuotePush:
        nesting++;
        break;
      case para_LcontPop:
      case para_QuotePop:
        assert(nesting > 0);
        nesting--;
        break;

        /*
         * Chapter and section titles: start a new Help topic.
         */
      case para_Chapter:
      case para_Appendix:
      case para_UnnumberedChapter:
      case para_Heading:
      case para_Subsect:

        if (!done_contents_topic) {
            paragraph *p;

            /*
             * If this is the first section title we've seen, then
             * we're currently still in the contents topic. We
             * should therefore finish up the contents page by
             * writing a nav menu.
             */
            for (p = sourceform; p; p = p->next) {
                if (p->type == para_Chapter ||
                    p->type == para_Appendix ||
                    p->type == para_UnnumberedChapter)
                    whlp_navmenu(&state, p, &conf);
            }

            done_contents_topic = TRUE;
        }

        if (lastsect && lastsect->child) {
            paragraph *q;
            /*
             * Do a navigation menu for the previous section we
             * were in.
             */
            for (q = lastsect->child; q; q = q->sibling)
                whlp_navmenu(&state, q, &conf);
        }
        {
            rdstringc rs = {0, 0, NULL};
            WHLP_TOPIC new_topic, parent_topic;
            char *macro, *topicid;
            charset_state cstate = CHARSET_INIT_STATE;

            new_topic = p->private_data;
            whlp_browse_link(h, state.curr_topic, new_topic);
            state.curr_topic = new_topic;

            if (p->kwtext) {
                whlp_rdaddwc(&rs, p->kwtext, &conf, &cstate);
                whlp_rdadds(&rs, conf.sectsuffix, &conf, &cstate);
            }
            whlp_rdaddwc(&rs, p->words, &conf, &cstate);
            whlp_rdadds(&rs, NULL, &conf, &cstate);

            if (p->parent == NULL)
                parent_topic = contents_topic;
            else
                parent_topic = (WHLP_TOPIC)p->parent->private_data;
            topicid = whlp_topic_id(parent_topic);
            macro = smalloc(100+strlen(topicid));
            sprintf(macro,
                    "CBB(\"btn_up\",\"JI(`',`%s')\");EB(\"btn_up\")",
                    topicid);
            whlp_begin_topic(h, new_topic,
                             rs.text ? rs.text : "",
                             macro, NULL);
            sfree(macro);

            {
                /*
                 * Output the .cnt entry.
                 * 
                 * WinHelp has a bug involving having an internal
                 * node followed by a leaf at the same level: the
                 * leaf is output at the wrong level. We can mostly
                 * work around this by modifying the leaf level
                 * itself (see whlp_contents_write), but this
                 * doesn't work for top-level sections since we
                 * can't turn a level-1 leaf into a level-0 one. So
                 * for top-level leaf sections (Bibliography
                 * springs to mind), we output an internal node
                 * containing only the leaf for that section.
                 */
                int i;
                paragraph *q;

                /* Count up the level. */
                i = 1;
                for (q = p; q->parent; q = q->parent) i++;

                if (p->child || !p->parent) {
                    /*
                     * If p has children then it needs to be a
                     * folder; if it has no parent then it needs to
                     * be a folder to work around the bug.
                     */
                    whlp_contents_write(&state, i, rs.text, NULL);
                    i++;
                }
                whlp_contents_write(&state, i, rs.text, new_topic);
            }

            sfree(rs.text);

            whlp_begin_para(h, WHLP_PARA_NONSCROLL);
            state.cstate = charset_init_state;
            if (p->kwtext) {
                whlp_mkparagraph(&state, FONT_TITLE, p->kwtext, FALSE, &conf);
                whlp_set_font(h, FONT_TITLE);
                whlp_wtext(&state, conf.sectsuffix);
            }
            whlp_mkparagraph(&state, FONT_TITLE, p->words, FALSE, &conf);
            whlp_wtext(&state, NULL);
            whlp_end_para(h);

            lastsect = p;
        }
        break;

      case para_Rule:
        whlp_para_attr(h, WHLP_PARA_SPACEBELOW, 12);
        whlp_para_attr(h, WHLP_PARA_ALIGNMENT, WHLP_ALIGN_CENTRE);
        whlp_begin_para(h, WHLP_PARA_SCROLL);
        whlp_set_font(h, FONT_RULE);
        state.cstate = charset_init_state;
#define TEN L"\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0"
#define TWENTY TEN TEN
#define FORTY TWENTY TWENTY
#define EIGHTY FORTY FORTY
        state.cstate = charset_init_state;
        whlp_wtext(&state, EIGHTY);
        whlp_wtext(&state, NULL);
#undef TEN
#undef TWENTY
#undef FORTY
#undef EIGHTY
        whlp_end_para(h);
        break;

      case para_Normal:
      case para_Copyright:
      case para_DescribedThing:
      case para_Description:
      case para_BiblioCited:
      case para_Bullet:
      case para_NumberedList:
        whlp_para_attr(h, WHLP_PARA_SPACEBELOW, 12);
        if (p->type == para_Bullet || p->type == para_NumberedList) {
            whlp_para_attr(h, WHLP_PARA_LEFTINDENT, 72*nesting + 72);
            whlp_para_attr(h, WHLP_PARA_FIRSTLINEINDENT, -36);
            whlp_set_tabstop(h, 72, WHLP_ALIGN_LEFT);
            whlp_begin_para(h, WHLP_PARA_SCROLL);
            whlp_set_font(h, FONT_NORMAL);
            state.cstate = charset_init_state;
            if (p->type == para_Bullet) {
                whlp_wtext(&state, conf.bullet);
            } else {
                whlp_mkparagraph(&state, FONT_NORMAL, p->kwtext, FALSE, &conf);
                whlp_wtext(&state, conf.listsuffix);
            }
            whlp_wtext(&state, NULL);
            whlp_tab(h);
        } else {
            whlp_para_attr(h, WHLP_PARA_LEFTINDENT,
                           72*nesting + (p->type==para_Description ? 72 : 0));
            whlp_begin_para(h, WHLP_PARA_SCROLL);
        }

        state.cstate = charset_init_state;

        if (p->type == para_BiblioCited) {
            whlp_mkparagraph(&state, FONT_NORMAL, p->kwtext, FALSE, &conf);
            whlp_wtext(&state, L" ");
        }

        whlp_mkparagraph(&state, FONT_NORMAL, p->words, FALSE, &conf);
        whlp_wtext(&state, NULL);
        whlp_end_para(h);
        break;

      case para_Code:
        /*
         * In a code paragraph, each individual word is a line. For
         * Help files, we will have to output this as a set of
         * paragraphs, all but the last of which don't set
         * SPACEBELOW.
         */
        {
            word *w;
            wchar_t *t, *e, *tmp;

            for (w = p->words; w; w = w->next) if (w->type == word_WeakCode) {
                t = w->text;
                if (w->next && w->next->type == word_Emph) {
                    w = w->next;
                    e = w->text;
                } else
                    e = NULL;

                if (!w->next)
                    whlp_para_attr(h, WHLP_PARA_SPACEBELOW, 12);

                whlp_para_attr(h, WHLP_PARA_LEFTINDENT, 72*nesting);
                whlp_begin_para(h, WHLP_PARA_SCROLL);
                state.cstate = charset_init_state;
                while (e && *e && *t) {
                    int n;
                    int ec = *e;

                    for (n = 0; t[n] && e[n] && e[n] == ec; n++);
                    if (ec == 'i')
                        whlp_set_font(h, FONT_ITAL_CODE);
                    else if (ec == 'b')
                        whlp_set_font(h, FONT_BOLD_CODE);
                    else
                        whlp_set_font(h, FONT_CODE);
                    tmp = snewn(n+1, wchar_t);
                    ustrncpy(tmp, t, n);
                    tmp[n] = L'\0';
                    whlp_wtext(&state, tmp);
                    whlp_wtext(&state, NULL);
                    state.cstate = charset_init_state;
                    sfree(tmp);
                    t += n;
                    e += n;
                }
                whlp_set_font(h, FONT_CODE);
                whlp_wtext(&state, t);
                whlp_wtext(&state, NULL);
                whlp_end_para(h);
            }
        }
        break;
    }

    fclose(state.cntfp);
    whlp_close(h, conf.filename);

    /*
     * Loop over the index entries, cleaning up our final text
     * forms.
     */
    for (i = 0; (ie = index234(idx->entries, i)) != NULL; i++) {
        sfree(ie->backend_data);
    }

    sfree(conf.filename);
    sfree(cntname);
}

static void whlp_contents_write(struct bk_whlp_state *state,
                                int level, char *text, WHLP_TOPIC topic) {
    /*
     * Horrifying bug in WinHelp. When dropping a section level or
     * more without using a folder-type entry, WinHelp accidentally
     * adds one to the section level. So we correct for that here.
     */
    if (state->cnt_last_level > level && topic)
        state->cnt_workaround = -1;
    else if (!topic)
        state->cnt_workaround = 0;
    state->cnt_last_level = level;

    fprintf(state->cntfp, "%d ", level + state->cnt_workaround);
    while (*text) {
        if (*text == '=')
            fputc('\\', state->cntfp);
        fputc(*text, state->cntfp);
        text++;
    }
    if (topic)
        fprintf(state->cntfp, "=%s", whlp_topic_id(topic));
    fputc('\n', state->cntfp);
}

static void whlp_navmenu(struct bk_whlp_state *state, paragraph *p,
                         whlpconf *conf) {
    whlp_begin_para(state->h, WHLP_PARA_SCROLL);
    whlp_start_hyperlink(state->h, (WHLP_TOPIC)p->private_data);
    state->cstate = charset_init_state;
    if (p->kwtext) {
        whlp_mkparagraph(state, FONT_NORMAL, p->kwtext, TRUE, conf);
        whlp_set_font(state->h, FONT_NORMAL);
        whlp_wtext(state, conf->sectsuffix);
    }
    whlp_mkparagraph(state, FONT_NORMAL, p->words, TRUE, conf);
    whlp_wtext(state, NULL);
    whlp_end_hyperlink(state->h);
    whlp_end_para(state->h);

}

static void whlp_mkparagraph(struct bk_whlp_state *state,
                             int font, word *text, int subsidiary,
                             whlpconf *conf) {
    keyword *kwl;
    int deffont = font;
    int currfont = -1;
    int newfont;
    paragraph *xref_target = NULL;

    for (; text; text = text->next) switch (text->type) {
      case word_HyperLink:
      case word_HyperEnd:
        break;

      case word_IndexRef:
        if (subsidiary) break;         /* disabled in subsidiary bits */
        {
            indextag *tag = index_findtag(state->idx, text->text);
            int i;
            if (!tag)
                break;
            for (i = 0; i < tag->nrefs; i++)
                whlp_index_term(state->h, tag->refs[i]->backend_data,
                                state->curr_topic);
        }
        break;

      case word_UpperXref:
      case word_LowerXref:
        if (subsidiary) break;         /* disabled in subsidiary bits */
        kwl = kw_lookup(state->keywords, text->text);
        assert(xref_target == NULL);
        if (kwl) {
            if (kwl->para->type == para_NumberedList) {
                break;                 /* don't xref to numbered list items */
            } else if (kwl->para->type == para_BiblioCited) {
                /*
                 * An xref to a bibliography item jumps to the section
                 * containing it.
                 */
                if (kwl->para->parent)
                    xref_target = kwl->para->parent;
                else
                    break;
            } else {
                xref_target = kwl->para;
            }
            whlp_start_hyperlink(state->h,
                                 (WHLP_TOPIC)xref_target->private_data);
        }
        break;

      case word_XrefEnd:
        if (subsidiary) break;         /* disabled in subsidiary bits */
        if (xref_target)
            whlp_end_hyperlink(state->h);
        xref_target = NULL;
        break;
        
      case word_Normal:
      case word_Emph:
      case word_Code:
      case word_WeakCode:
      case word_WhiteSpace:
      case word_EmphSpace:
      case word_CodeSpace:
      case word_WkCodeSpace:
      case word_Quote:
      case word_EmphQuote:
      case word_CodeQuote:
      case word_WkCodeQuote:
        if (towordstyle(text->type) == word_Emph)
            newfont = deffont + FONT_EMPH;
        else if (towordstyle(text->type) == word_Code ||
                 towordstyle(text->type) == word_WeakCode)
            newfont = deffont + FONT_CODE;
        else
            newfont = deffont;
        if (newfont != currfont) {
            currfont = newfont;
            whlp_set_font(state->h, newfont);
        }
        if (removeattr(text->type) == word_Normal) {
            if (cvt_ok(conf->charset, text->text) || !text->alt)
                whlp_wtext(state, text->text);
            else
                whlp_mkparagraph(state, deffont, text->alt, FALSE, conf);
        } else if (removeattr(text->type) == word_WhiteSpace) {
            whlp_wtext(state, L" ");
        } else if (removeattr(text->type) == word_Quote) {
            whlp_wtext(state,
                       quoteaux(text->aux) == quote_Open ?
                       conf->lquote : conf->rquote);
        }
        break;
    }
}

static void whlp_rdaddwc(rdstringc *rs, word *text, whlpconf *conf,
                         charset_state *state) {
    charset_state ourstate = CHARSET_INIT_STATE;

    if (!state)
        state = &ourstate;

    for (; text; text = text->next) switch (text->type) {
      case word_HyperLink:
      case word_HyperEnd:
      case word_UpperXref:
      case word_LowerXref:
      case word_XrefEnd:
      case word_IndexRef:
        break;

      case word_Normal:
      case word_Emph:
      case word_Code:
      case word_WeakCode:
      case word_WhiteSpace:
      case word_EmphSpace:
      case word_CodeSpace:
      case word_WkCodeSpace:
      case word_Quote:
      case word_EmphQuote:
      case word_CodeQuote:
      case word_WkCodeQuote:
        assert(text->type != word_CodeQuote &&
               text->type != word_WkCodeQuote);
        if (removeattr(text->type) == word_Normal) {
            if (cvt_ok(conf->charset, text->text) || !text->alt)
                whlp_rdadds(rs, text->text, conf, state);
            else
                whlp_rdaddwc(rs, text->alt, conf, state);
        } else if (removeattr(text->type) == word_WhiteSpace) {
            whlp_rdadds(rs, L" ", conf, state);
        } else if (removeattr(text->type) == word_Quote) {
            whlp_rdadds(rs, quoteaux(text->aux) == quote_Open ?
                        conf->lquote : conf->rquote, conf, state);
        }
        break;
    }

    if (state == &ourstate)
        whlp_rdadds(rs, NULL, conf, state);
}

static void whlp_rdadds(rdstringc *rs, const wchar_t *text, whlpconf *conf,
                        charset_state *state)
{
    charset_state ourstate = CHARSET_INIT_STATE;
    int textlen = text ? ustrlen(text) : 0;
    char outbuf[256];
    int ret;

    if (!state)
        state = &ourstate;

    while (textlen > 0 &&
           (ret = charset_from_unicode(&text, &textlen, outbuf,
                                       lenof(outbuf)-1,
                                       conf->charset, state, NULL)) > 0) {
        outbuf[ret] = '\0';
        rdaddsc(rs, outbuf);
    }

    if (text == NULL || state == &ourstate) {
        if ((ret = charset_from_unicode(NULL, 0, outbuf, lenof(outbuf)-1,
                                        conf->charset, state, NULL)) > 0) {
            outbuf[ret] = '\0';
            rdaddsc(rs, outbuf);
        }
    }
}

static void whlp_wtext(struct bk_whlp_state *state, const wchar_t *text)
{
    int textlen = text ? ustrlen(text) : 0;
    char outbuf[256];
    int ret;

    while (textlen > 0 &&
           (ret = charset_from_unicode(&text, &textlen, outbuf,
                                       lenof(outbuf)-1,
                                       state->charset, &state->cstate,
                                       NULL)) > 0) {
        outbuf[ret] = '\0';
        whlp_text(state->h, outbuf);
    }

    if (text == NULL) {
        if ((ret = charset_from_unicode(NULL, 0, outbuf, lenof(outbuf)-1,
                                        state->charset, &state->cstate,
                                        NULL)) > 0) {
            outbuf[ret] = '\0';
            whlp_text(state->h, outbuf);
        }
    }
}