/* Copyright (C) 2001-2006 Artifex Software, Inc.
   All Rights Reserved.
  
   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied, modified
   or distributed except as expressly authorized under the terms of that
   license.  Refer to licensing information at http://www.artifex.com/
   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
*/

/* $Id: fapiufst.c 8022 2007-06-05 22:23:38Z giles $ */
/* Agfa UFST plugin */

/* GS includes : */
#include "stdio_.h"
#include "memory_.h"
#include "math_.h"
#include "ierrors.h"
#include "iplugin.h"
#include "ifapi.h"
#include "strmio.h"
/* UFST includes : */
#undef true	/* GS/UFST definition conflict. */
#undef false	/* GS/UFST definition conflict. */
#include "cgconfig.h"
#include "ufstport.h"
#include "dbg_ufst.h"
#include "shareinc.h"
#include "t1isfnt.h"
#include "cgmacros.h"
#include "sfntenum.h"
#define DOES_ANYONE_USE_THIS_STRUCTURE /* see TTPCLEO.H, UFST 4.2 */
#include "ttpcleo.h"
#undef  DOES_ANYONE_USE_THIS_STRUCTURE
#include "gxfapiu.h"

typedef struct fapi_ufst_server_s fapi_ufst_server;

#if UFST_REENTRANT
#define FSA_FROM_SERVER IF_STATE *pIFS = &r->IFS
#else
EXTERN IF_STATE if_state;
#define FSA_FROM_SERVER IF_STATE *pIFS = &if_state;    (void)r; (void)pIFS;
private fapi_ufst_server *static_server_ptr_for_ufst_callback = 0;
#endif

GLOBAL UW16  PCLswapHdr( FSP LPUB8 p, UW16 gifct ); /* UFST header doesn't define it. */

typedef struct pcleo_glyph_list_elem_s pcleo_glyph_list_elem;
struct pcleo_glyph_list_elem_s {
    UW16 chId;
    pcleo_glyph_list_elem *next;
    /* more data follows here depending on font type */
};

typedef struct {
    SL32 font_id;
    uint tt_font_body_offset;
    UW16 is_disk_font;
    UW16 font_type;
    UW16 platformId;
    UW16 specificId;
    pcleo_glyph_list_elem *glyphs;
    char decodingID[40];
} ufst_common_font_data;

typedef struct { 
    PCLETTO_CHR_HDR h;
    UW16   add_data;
    UW16   charDataSize;
    UW16   glyphID;
} PCLETTO_CHDR;

struct fapi_ufst_server_s {
    FAPI_server If;
    int bInitialized;
    FAPI_font *ff;
    i_plugin_client_memory client_mem;
    IF_STATE IFS;
    FONTCONTEXT fc;
    void *char_data;
    bool bRaster;
    bool ufst_is_singleton;
    double tran_xx, tran_xy, tran_yx, tran_yy;
    fco_list_elem *fco_list;
    FAPI_retcode callback_error;
    FAPI_metrics_type metrics_type;
    FracInt sb_x, aw_x; /* replaced PS metrics. */
};

/* Type casts : */

private inline fapi_ufst_server *If_to_I(FAPI_server *If)
{   return (fapi_ufst_server *)If;
}

private inline fapi_ufst_server *IFS_to_I(IF_STATE *pIFS)
{   return (fapi_ufst_server *)((char *)pIFS - offset_of(fapi_ufst_server, IFS));
}

/*------------------ FAPI_server members ------------------------------------*/

private inline void release_char_data_inline(fapi_ufst_server *r)
{   /*  The server keeps character raster between calls to get_char_raster_metrics
        and get_char_raster, as well as between calls to get_char_outline_metrics
        and get_char_outline. Meanwhile this regular
        sequence of calls may be interrupted by an error in CDefProc or setchachedevice2,
        which may be invoked between them. In this case Ghostscript
        is unable to provide a signal to FAPI that the data are not
        longer needed. This would cause memory leaks in UFST heap.
        To work around this, appropriate server's entries check whether
        raster data were left after a previous call, and ultimately release them.
        This function provides it.
    */
    if (r->char_data != NULL) {
	FSA_FROM_SERVER;

        CHARfree(FSA (MEM_HANDLE)r->char_data);
        r->char_data = 0;
    }
}

/*
 * In the language switch build (which we detect because PSI_INCLUDED
 * is defined), we use the gx_UFST_init() call to initialize the UFST,
 * rather than calling into the UFST directly. That has the advantage
 * that the same UFST configuration is used for PCL and PS, but the
 * disadvantage that the dynamic parameters set in server_param are
 * not available. Thus, it is switched through this compile time option.
*/
private FAPI_retcode open_UFST(fapi_ufst_server *r, const byte *server_param, int server_param_size)
{
    int code;
    SW16 fcHandle;
    int l;
    char ufst_root_dir[1024] = "";
    char sPlugIn[1024] = "";
    bool bSSdir = false, bPlugIn = false;
    const char *keySSdir = "UFST_SSdir=";
    const int keySSdir_length = strlen(keySSdir);
    const char *keyPlugIn = "UFST_PlugIn=";
    const int keyPlugIn_length = strlen(keyPlugIn);
    const char sep = gp_file_name_list_separator;
    const byte *p = server_param, *e = server_param + server_param_size, *q;
    FSA_FROM_SERVER;

    for (; p < e ; p = q + 1) {
	for (q = p; q < e && *q != sep; q++)
	    /* DO_NOTHING */;
	l = q - p;
	if (l > keySSdir_length && !memcmp(p, keySSdir, keySSdir_length)) {
	    l = q - p - keySSdir_length;
	    if (l > sizeof(ufst_root_dir) - 1)
		l = sizeof(ufst_root_dir) - 1;
	    memcpy(ufst_root_dir, p + keySSdir_length, l);
	    ufst_root_dir[l] = 0;
	    bSSdir = true;
	} else if (l > keyPlugIn_length && !memcmp(p, keyPlugIn, keyPlugIn_length)) {
	    l = q - p - keyPlugIn_length;
	    if (l > sizeof(sPlugIn) - 1)
		l = sizeof(sPlugIn) - 1;
	    memcpy(sPlugIn, p + keyPlugIn_length, l);
	    sPlugIn[l] = 0;
	    bPlugIn = true;
	} else
	    eprintf("Warning: Unknown UFST parameter ignored.\n");
    }
#if !NO_SYMSET_MAPPING
    if (!bSSdir) {
	strcpy(ufst_root_dir, ".");
	eprintf("Warning: UFST_SSdir is not specified, will search *.ss files in the curent directory.\n");
    }
#endif
    code = gx_UFST_init((const UB8 *)ufst_root_dir);
    if (code < 0)
	return code;
    r->ufst_is_singleton = (code == 1);
    if (bPlugIn) {
	if ((code = gx_UFST_open_static_fco(sPlugIn, &fcHandle)) != 0)
	    return code;
	if ((code = CGIFfco_Plugin(FSA fcHandle)) != 0)
	    return code;
    } else {
#ifdef FCO_RDR
	eprintf("Warning: UFST_PlugIn is not specified, some characters may be missing.\n");
#endif
    }
    return 0;
}		      

private LPUB8 impl_PCLchId2ptr(FSP UW16 chId);

private FAPI_retcode ensure_open(FAPI_server *server, const byte *server_param, int server_param_size)
{   fapi_ufst_server *r = If_to_I(server);
    int code;

    if (r->bInitialized)
        return 0;
    r->bInitialized = 1;
    {
	code = open_UFST(r, server_param, server_param_size);
	if (code < 0) {
	    eprintf("Error opening the UFST font server.\n");
	    return code;
	}
    }
    gx_set_UFST_Callbacks(NULL, impl_PCLchId2ptr, NULL);
    return 0;
}

private UW16 get_font_type(stream *f)
{   char buf[20], mark_PS[]="%!";
    int i;

    if (sfread(buf, 1, sizeof(buf), f) != sizeof(buf))
        return 0;
    if (buf[0] == 0x15 || buf[0] == 0x00) /* fixme : don't know how to do correctly. */
        return FC_FCO_TYPE;
    for (i = 0; i < sizeof(buf) - sizeof(mark_PS); i++)
        if(!memcmp(buf + i, mark_PS, sizeof(mark_PS) - 1))
            return FC_PST1_TYPE;
    if (buf[0] == '\0' && buf[1] == '\1')
        return FC_TT_TYPE;
    if (buf[0] == 't' && buf[1] == 't')
        return FC_TT_TYPE;
    return 0; /* fixme : unknown type - actually an error. */
}

    
private int choose_decoding_general(fapi_ufst_server *r, ufst_common_font_data *d, const char *cmapId)
{ 
    if (!d->decodingID[0])
	strncpy(d->decodingID, "Unicode", sizeof(d->decodingID));
    /*    fixme : must depend on charset used in the font.  */
    return 1;
}

private int choose_decoding_TT(fapi_ufst_server *r, ufst_common_font_data *d, const char *cmapId)
{   
#if TT_ROM || TT_DISK
    int platId, specId, i;
    CMAP_QUERY q;
    UW16 font_access;
    bool failed;
    void *p = (d->is_disk_font ? (void *)(d + 1) : (void *)((UB8 *)d + d->tt_font_body_offset));
    FSA_FROM_SERVER;

    if (sscanf(cmapId, "%d.%d", &platId, &specId) != 2)
        return 0;
    font_access = pIFS->font_access;
    pIFS->font_access = (d->is_disk_font ? DISK_ACCESS : ROM_ACCESS);
    failed = CGIFtt_cmap_query(FSA p, r->fc.ttc_index, &q);
    pIFS->font_access = font_access;
    if(failed)
        return 0;
    for (i = 0; i < q.numCmap; i++)
        if (q.entry[i].platId == platId && q.entry[i].specId == specId) {
            d->platformId = platId;
            d->specificId = specId;
            return 1;
        }
    return 0;
#else
    if (!d->decodingID[0])
	strncpy(d->decodingID, "Unicode", sizeof(d->decodingID));
    return 1;
#endif
}

private void scan_xlatmap(fapi_ufst_server *r, ufst_common_font_data *d, const char *xlatmap, const char *font_kind, 
                                    int (*choose_proc)(fapi_ufst_server *r, ufst_common_font_data *d, const char *cmapId))
{   const char *p = xlatmap;

    while(*p) {
        int good_kind =!strcmp(p, font_kind);
        p += strlen(p) + 2;
        while(*p) {
            const char *cmapId = p, *decodingID = p + strlen(p) + 1;
            strncpy(d->decodingID, decodingID, sizeof(d->decodingID));
            if (!decodingID[0])
                break;
            p = decodingID + strlen(decodingID) + 1;
            if (good_kind)
                if (choose_proc(r, d, cmapId))
                    return;
        }
    }
    d->decodingID[0] = 0;
}

private void choose_decoding(fapi_ufst_server *r, ufst_common_font_data *d, const char *xlatmap)
{   if (xlatmap != 0)
        switch (d->font_type) {
            case FC_IF_TYPE: /* fixme */ break;
            case FC_PST1_TYPE: scan_xlatmap(r, d, xlatmap, "PostScript", choose_decoding_general); break;
            case FC_TT_TYPE:   scan_xlatmap(r, d, xlatmap, "TrueType", choose_decoding_TT); break;
            case FC_FCO_TYPE:  scan_xlatmap(r, d, xlatmap, "Microtype", choose_decoding_general); break;
        } 
}

private inline void store_word(byte **p, ushort w)
{   *((*p)++) = w / 256;
    *((*p)++) = w % 256;
    
}

private LPUB8 get_TT_glyph(fapi_ufst_server *r, FAPI_font *ff, UW16 chId)
{   pcleo_glyph_list_elem *g;
    PCLETTO_CHDR *h;
    ufst_common_font_data *d = (ufst_common_font_data *)r->fc.font_hdr - 1;
    LPUB8 q;
    ushort glyph_length = ff->get_glyph(ff, chId, 0, 0);
    bool use_XL_format = ff->is_mtx_skipped;

    /*
     * The client must set ff->is_mtx_skipped iff
     * it requests a replaced lsb for True Type.
     * If it is set, a replaced width to be supplied.
     * This constraint is derived from UFST restriction :
     * the font header format must be compatible with
     * glyph header format.
     */

    if (glyph_length == (ushort)-1) {
        r->callback_error = e_invalidfont;
        return 0;
    }
    g = (pcleo_glyph_list_elem *)r->client_mem.alloc(&r->client_mem, 
	    sizeof(pcleo_glyph_list_elem) + 
	    (use_XL_format ? 12 : sizeof(PCLETTO_CHDR)) + glyph_length + 2, 
	    "PCLETTO char");
    if (g == 0) {
        r->callback_error = e_VMerror;
        return 0;
    }
    g->chId = chId;
    g->next = d->glyphs;
    d->glyphs = g;
    h = (PCLETTO_CHDR *)(g + 1);
    h->h.format = 15;
    if (use_XL_format) {
	h->h.continuation = 2; 
	q = (LPUB8)h + 2;
	store_word(&q, (ushort)(glyph_length + 10));
	store_word(&q, (ushort)(r->sb_x >> r->If.frac_shift)); /* see can_replace_metrics */
	store_word(&q, (ushort)(r->aw_x >> r->If.frac_shift));
	store_word(&q, 0);
	store_word(&q, chId);
    } else {
	h->h.continuation = 0;
	h->h.descriptorsize = 4;
	h->h.ch_class = 15;
	h->add_data = 0;
	q = (LPUB8)&h->charDataSize;
	store_word(&q, (ushort)(glyph_length + 4));
	store_word(&q, chId);
    }
    if (ff->get_glyph(ff, chId, (LPUB8)q, glyph_length) == (ushort)-1) {
        r->callback_error = e_invalidfont;
        return 0;
    }
    q += glyph_length;
    store_word(&q, 0); /* checksum */
    return (LPUB8)h;
    /*
     * The metrics replacement here is done only for the case
     * corresponding to non-disk TT fonts with MetricsCount != 0;
     * Other cases are not supported because UFST cannot handle them.
     * Here we don't take care of cases which can_replace_metrics rejects.
     *
     * We don't care of metrics for subglyphs, because
     * it is ignored by TT interpreter.
     */
}

private LPUB8 get_T1_glyph(fapi_ufst_server *r, FAPI_font *ff, UW16 chId)
{   
#if PST1_SFNTI
    ushort glyph_length = ff->get_glyph(ff, chId, 0, 0);
    LPUB8 q;
    pcleo_glyph_list_elem *g = (pcleo_glyph_list_elem *)r->client_mem.alloc(&r->client_mem, 
		    sizeof(pcleo_glyph_list_elem) + sizeof(PS_CHAR_HDR) + 2 + 2 + glyph_length + 1, "PSEO char");
    PS_CHAR_HDR *h;
    ufst_common_font_data *d = (ufst_common_font_data *)r->fc.font_hdr - 1;
    FSA_FROM_SERVER;

    if (g == 0 || glyph_length == (ushort)-1) {
        r->callback_error = e_invalidfont;
        return 0;
    }
    g->chId = chId;
    g->next = d->glyphs;
    d->glyphs = g;
    h = (PS_CHAR_HDR *)(g + 1);
    h->format = 30;           /* raster=4, DJ=5, IF=10, TT=15, PS=30 */
    h->continuation = 0;     /* always 0 */
    h->descriptorsize = 2;   /* always 2 */
    h->ch_class = 11;           /* contour=3, compound=4, tt=10, ps=11 */
    h->len = 0;              /* # of bytes to follow (not including csum) */
    q = (byte *)h + sizeof(*h);
    /* A workaround for UFST4.6 bug in t1idecod.c (UNPACK_WORD uses pIFS->ph instead ph) : 
       setting Namelen=4, rather normally it must be 0. */
    q[0] = 0; /* Namelen */
    q[1] = 4; /* Namelen */
    q[2] = (glyph_length) / 256; /* Datalen */
    q[3] = (glyph_length) % 256; /* Datalen */
    /* Glyph name goes here, but we don't use it. */
    q += 4;
    glyph_length = ff->get_glyph(ff, chId, q, glyph_length);
    q += glyph_length;
    *q = 1; /* Decrypt flag */
    pIFS->ph = (byte *)h + sizeof(*h); /* A workaround for UFST4.6 bug in t1idecod.c (UNPACK_WORD uses pIFS->ph instead ph) */
    return (LPUB8)h;
#else
    return 0;
#endif
}

private pcleo_glyph_list_elem * find_glyph(ufst_common_font_data *d, UW16 chId)
{   pcleo_glyph_list_elem *e;

    for (e = d->glyphs; e != 0; e = e->next)
        if (e->chId == chId)
            return e;
    return 0;
}

/* UFST callback : */
private LPUB8 impl_PCLchId2ptr(FSP UW16 chId)
{   
#if UFST_REENTRANT
    fapi_ufst_server *r = IFS_to_I(pIFS);
#else
    fapi_ufst_server *r = static_server_ptr_for_ufst_callback;
#endif
    FAPI_font *ff = r->ff;
    ufst_common_font_data *d = (ufst_common_font_data *)r->fc.font_hdr - 1;
    pcleo_glyph_list_elem *g = find_glyph(d, chId);
    LPUB8 result = 0;

    if (g != 0)
        result = (LPUB8)(g + 1);
    if ((r->fc.format & FC_FONTTYPE_MASK) == FC_PST1_TYPE)
        result = get_T1_glyph(r, ff, chId);
    if ((r->fc.format & FC_FONTTYPE_MASK) == FC_TT_TYPE)
        result = get_TT_glyph(r, ff, chId);
    return result;
}

private inline void pack_word(LPUB8 *p, UW16 v)
{   LPUB8 q = (LPUB8)&v;

#if (BYTEORDER == LOHI) /* defied in UFST includes */
         (*p)[1] = q[0];
         (*p)[0] = q[1];
#else
        *(UW16 *)(*p) = v;
#endif
    *p += 2;
}

private inline void pack_long(LPUB8 *p, UL32 v)
{   LPUB8 q = (LPUB8)&v;

#if (BYTEORDER == LOHI) /* defied in UFST includes */
         (*p)[3] = q[0];
         (*p)[2] = q[1];
         (*p)[1] = q[2];
         (*p)[0] = q[3];
#else
        *(UL32 *)(*p) = v;
#endif
    *p += 4;
}

private inline void pack_float(LPUB8 *p, float v)
{   sprintf((char *)(*p), "%f", v);
    *p += strlen((const char *)*p) + 1;
}

#define PACK_ZERO(p) *(p++) = 0
#define PACK_BYTE(p, c) *(p++) = c
#define PACK_WORD(p, i, var) pack_word(&p, ff->get_word(ff, var, i))
#define PACK_LONG(p, i, var) pack_long(&p, ff->get_long(ff, var, i))

private void pack_pseo_word_array(fapi_ufst_server *r, FAPI_font *ff, UB8 **p, 
				  UW16 max_count, fapi_font_feature count_id, fapi_font_feature array_id)
{   UW16 k = min(ff->get_word(ff, count_id, 0), max_count), j;

    pack_word(p, k);
    for (j = 0; j < k; j++)
        PACK_WORD(*p, j, array_id);
    for (; j < max_count; j++)
        pack_word(p, 0);
}

private void pack_pseo_fhdr(fapi_ufst_server *r, FAPI_font *ff, UB8 *p)
{   ushort j, n, skip = 0;

    while ((UL32)p & 0x03) /* align to QUADWORD */
	PACK_ZERO(p);
    pack_long(&p, 1);  /* format = 1 */
    for (j = 0; j < 6; j++)
        pack_float(&p, ff->get_float(ff, FAPI_FONT_FEATURE_FontMatrix, j));
    while ((UL32)p & 0x03) /* align to QUADWORD */
	PACK_ZERO(p);
    /* UFST has no definition for PSEO structure, so implement serialization : */
    PACK_LONG(p, 0, FAPI_FONT_FEATURE_UniqueID);
    PACK_LONG(p, 0, FAPI_FONT_FEATURE_BlueScale);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_Weight);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_ItalicAngle);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_IsFixedPitch);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_UnderLinePosition);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_UnderlineThickness);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_FontType);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_FontBBox);
    PACK_WORD(p, 1, FAPI_FONT_FEATURE_FontBBox);
    PACK_WORD(p, 2, FAPI_FONT_FEATURE_FontBBox);
    PACK_WORD(p, 3, FAPI_FONT_FEATURE_FontBBox);
    pack_pseo_word_array(r, ff, &p, 14, FAPI_FONT_FEATURE_BlueValues_count, FAPI_FONT_FEATURE_BlueValues);
    pack_pseo_word_array(r, ff, &p, 10, FAPI_FONT_FEATURE_OtherBlues_count, FAPI_FONT_FEATURE_OtherBlues);
    pack_pseo_word_array(r, ff, &p, 14, FAPI_FONT_FEATURE_FamilyBlues_count, FAPI_FONT_FEATURE_FamilyBlues);
    pack_pseo_word_array(r, ff, &p, 10, FAPI_FONT_FEATURE_FamilyOtherBlues_count, FAPI_FONT_FEATURE_FamilyOtherBlues);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_BlueShift);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_BlueFuzz);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_StdHW);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_StdVW);
    pack_pseo_word_array(r, ff, &p, 12, FAPI_FONT_FEATURE_StemSnapH_count, FAPI_FONT_FEATURE_StemSnapH);
    pack_pseo_word_array(r, ff, &p, 12, FAPI_FONT_FEATURE_StemSnapV_count, FAPI_FONT_FEATURE_StemSnapV);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_ForceBold);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_LanguageGroup);
    PACK_WORD(p, 0, FAPI_FONT_FEATURE_lenIV);
    for (j = 0; j < 12; j++)
        PACK_ZERO(p), PACK_ZERO(p);     /* Reserved2 */
    /* max data size = 107 words + 6 floats in ASCII */
    n = ff->get_word(ff, FAPI_FONT_FEATURE_Subrs_count, 0);
    pack_word(&p, n);
    for (j = 0; j < n; j++) {
        ushort subr_len = ff->get_subr(ff, j, 0, 0);
        if (subr_len != 0) {
            pack_word(&p, j);
            pack_word(&p, subr_len);
            PACK_BYTE(p, 1); /* is_decrypted */
            ff->get_subr(ff, j, p, subr_len);
            p += subr_len;
        } else
            skip = 1;
    }
    if (skip)
        pack_word(&p, 0xFFFF);
}

private char *my_strdup(fapi_ufst_server *r, const char *s, const char *cname)
{   int l = strlen(s) + 1;
    char *p = (char *)r->client_mem.alloc(&r->client_mem, l, cname);

    if (p != 0)
        memcpy(p, s, l);
    return p;
}

private FAPI_retcode fco_open(fapi_ufst_server *r, const char *font_file_path, fco_list_elem **result)
{   int code;
    fco_list_elem *e = gx_UFST_find_static_fco(font_file_path);
    
    if (e != NULL) {   
	*result = e;   
	return 0;   
    } 
    for (e = r->fco_list; e != 0; e = e->next) {
        if (!strcmp(e->file_path, font_file_path))
            break;
    }
    if (e == 0) {
        SW16 fcHandle;
	FSA_FROM_SERVER;

	if ((code = CGIFfco_Open(FSA (UB8 *)font_file_path, &fcHandle)) != 0)
	    return code;
        e = (fco_list_elem *)r->client_mem.alloc(&r->client_mem, sizeof(*e), "fco_list_elem");
        if (e == 0) {
            CGIFfco_Close(FSA fcHandle);
            return e_VMerror;
        }
        e->open_count = 0;
        e->fcHandle = fcHandle;
        e->file_path = my_strdup(r, font_file_path, "fco_file_path");
        if (e->file_path == 0) {
            CGIFfco_Close(FSA fcHandle);
            r->client_mem.free(&r->client_mem, e, "fco_list_elem");
            return e_VMerror;
        }
        e->next = r->fco_list;
        r->fco_list = e;
    }
    e->open_count++;
    *result = e;
    return 0;
}

private FAPI_retcode make_font_data(fapi_ufst_server *r, const char *font_file_path, FAPI_font *ff, ufst_common_font_data **return_data)
{   ulong area_length = sizeof(ufst_common_font_data), tt_size = 0;
    LPUB8 buf;
    PCLETTO_FHDR *h;
    ufst_common_font_data *d;
    bool use_XL_format = ff->is_mtx_skipped;
    int code;
    FSA_FROM_SERVER;

    *return_data = 0;
    r->fc.ttc_index = ff->subfont;
    if (ff->font_file_path == NULL) {
        area_length += PCLETTOFONTHDRSIZE;
        if (ff->is_type1) {
            int subrs_count  = ff->get_word(ff, FAPI_FONT_FEATURE_Subrs_count, 0);
            int subrs_length = ff->get_long(ff, FAPI_FONT_FEATURE_Subrs_total_size, 0);
            int subrs_area_size = subrs_count * 5 + subrs_length + 2;
            area_length += 360 + subrs_area_size; /* some inprecise - see pack_pseo_fhdr */
        } else {
            tt_size  = ff->get_long(ff, FAPI_FONT_FEATURE_TT_size, 0);
            if (tt_size == 0)
                return e_invalidfont;
            area_length += tt_size + (use_XL_format ? 6 : 4) + 4 + 2;
        }
    } else
        area_length += strlen(font_file_path) + 1;
    buf = r->client_mem.alloc(&r->client_mem, area_length, "ufst font data");
    if (buf == 0)
        return e_VMerror;
    d = (ufst_common_font_data *)buf;
    d->tt_font_body_offset = 0;
    d->platformId = 0;
    d->specificId = 0;
    d->decodingID[0] = 0;
    d->glyphs = 0;
    d->is_disk_font = (ff->font_file_path != NULL);
    if (d->is_disk_font) {
	 fco_list_elem *e = gx_UFST_find_static_fco(font_file_path);   

	 if (e != NULL) {   
	     memcpy(d + 1, font_file_path, strlen(font_file_path) + 1);   
	     d->font_id = (e->fcHandle << 16) | ff->subfont;   
	     d->font_type = FC_FCO_TYPE;   
	 } else { 
	    stream *f = sfopen(font_file_path, "rb", (gs_memory_t *)(r->client_mem.client_data));
	    if (f == NULL) {
		eprintf1("fapiufst: Can't open %s\n", font_file_path);
		return e_undefinedfilename;
	    }
	    memcpy(d + 1, font_file_path, strlen(font_file_path) + 1);
	    d->font_type = get_font_type(f);
	    sfclose(f);
	    if (d->font_type == FC_FCO_TYPE) {
		fco_list_elem *e;
		if ((code = fco_open(r, font_file_path, &e)) != 0)
		    return code;
		d->font_id = (e->fcHandle << 16) | ff->subfont;
	    }
	}
    } else {
        d->font_type = (ff->is_type1 ? FC_PST1_TYPE : FC_TT_TYPE);
	d->font_id = ff->get_long(ff, FAPI_FONT_FEATURE_UniqueID, 0);
        h = (PCLETTO_FHDR *)(buf + sizeof(ufst_common_font_data));
        h->fontDescriptorSize = PCLETTOFONTHDRSIZE;
        h->descriptorFormat = 15;
        h->fontType = 11; /* wrong */                /*  3- 11=Unicode; 0,1,2 also possible */
        h->style_msb = 0; /* wrong */               /*  4- from PCLT table in TrueType font */
        h->reserved1 = 0;
        h->baselinePosition = 0; /* wrong */        /*  6- from head table in TT font; = 0 */
        h->cellWidth = 1024; /* wrong */               /*  8- head, use xMax - xMin */
        h->cellHeight = 1024; /* wrong */             /* 10- head, use yMax - yMin */
        h->orientation = 0;             /* 12- 0 */
        h->spacing = 1; /* wrong */                 /* 13- 1=proportional, 0-fixed pitch */
        h->characterSet = 56; /* wrong */            /* 14- same as symSetCode; =56 if unbound. */
        h->pitch = 1024; /* wrong */                   /* 16- PCLT */
        h->height = 0;                  /* 18- 0 if TrueType */
        h->xHeight = 512; /* wrong */                 /* 20- PCLT */
        h->widthType = 0; /* wrong */               /* 22- PCLT */
        h->style_lsb = 0; /* wrong */               /* 23- PCLT */
        h->strokeWeight = 0; /* wrong */            /* 24- PCLT */
        h->typeface_lsb = 0; /* wrong */            /* 25- PCLT */
        h->typeface_msb = 0; /* wrong */           /* 26- PCLT */
        h->serifStyle = 0; /* wrong */              /* 27- PCLT */
        h->quality = 0; /* wrong */                 /* 28- 2 if TrueType */
        h->placement = 0; /* wronfg */               /* 29- 0 if TrueType */
        h->underlinePosition = 0;       /* 30- 0 */
        h->underlineHeight = 0;         /* 31- 0 */
        h->textHeight = 102; /* wrong */              /* 32- from OS/2 table in TT font */
        h->textWidth = 1024; /* wrong */              /* 34- OS/2 */
        h->firstCode = 0;               /* 36- set to 0 if unbound */
        h->lastCode = 255; /* wrong */                /* 38- max number of downloadable chars if unbound */
        h->pitch_ext = 0;               /* 40- 0 if TrueType */
        h->height_ext = 0;              /* 41- 0 if TrueType */
        h->capHeight = 1024; /* wrong */               /* 42- PCLT */
        h->fontNumber = d->font_id;              /* 44- PCLT */
        h->fontName[0] = 0; /* wrong */            /* 48- PCLT */
        h->scaleFactor = 1024; /* wrong */             /* 64- head:unitsPerEm */
        h->masterUnderlinePosition = 0; /* wrong */ /* 66- post table, or -20% of em */
        h->masterUnderlineHeight = 0; /* wrong */   /* 68- post table, or 5% of em */
        h->fontScalingTechnology = 1;   /* 70- 1=TrueType; 0=Intellifont */
        h->variety = 0;                 /* 71- 0 if TrueType */
        memset((LPUB8)h + PCLETTOFONTHDRSIZE, 0 ,8); /* work around bug in PCLswapHdr : it wants format 10 */
        /*  fixme : Most fields above being marked "wrong" look unused by UFST.
            Need to check for sure.
        */
        /*  fixme : This code assumes 1-byte alignment for PCLETTO_FHDR structure.
            Use PACK_* macros to improve.
        */
        PCLswapHdr(FSA (UB8 *)h, 0);
        if (ff->is_type1) {
            LPUB8 fontdata = (LPUB8)h + PCLETTOFONTHDRSIZE;
            pack_pseo_fhdr(r, ff, fontdata);
        } else {
            LPUB8 pseg = (LPUB8)h + PCLETTOFONTHDRSIZE;
            LPUB8 fontdata = pseg + (use_XL_format ? 6 : 4);
            if (tt_size > 65000)
                return e_unregistered; /* Must not happen because we skept 'glyp', 'loca' and 'cmap'. */
            pseg[0] = 'G';
            pseg[1] = 'T';
	    if (use_XL_format) {
		pseg[2] = tt_size >> 24;
		pseg[3] = (tt_size >> 16) % 256;
		pseg[4] = (tt_size >> 8) % 256;
		pseg[5] = tt_size % 256;
	    } else {
		pseg[2] = tt_size / 256;
		pseg[3] = tt_size % 256;
	    }
            d->tt_font_body_offset = (LPUB8)fontdata - (LPUB8)d;
            if (ff->serialize_tt_font(ff, fontdata, tt_size))
                return e_invalidfont;
            *(fontdata + tt_size    ) = 255;
            *(fontdata + tt_size + 1) = 255;
            *(fontdata + tt_size + 2) = 0;
            *(fontdata + tt_size + 3) = 0;
            *(fontdata + tt_size + 4) = 0;
            *(fontdata + tt_size + 5) = 0;  /* checksum */
        }
    }
    *return_data = d;
    return 0;
}

private void prepare_typeface(fapi_ufst_server *r, ufst_common_font_data *d)
{   r->fc.format = d->font_type;
    r->fc.font_id = d->font_id;
    r->fc.font_hdr = (UB8 *)(d + 1);
    if (!d->is_disk_font)
        r->fc.format |= FC_EXTERN_TYPE;
}

private FAPI_retcode get_scaled_font(FAPI_server *server, FAPI_font *ff, 
         const FAPI_font_scale *font_scale, const char *xlatmap, FAPI_descendant_code dc)
{   fapi_ufst_server *r = If_to_I(server);
    FONTCONTEXT *fc = &r->fc;
    /*  Note : UFST doesn't provide handles for opened fonts,
        but copies FONTCONTEXT to IFSTATE and caches it.
        Due to this the plugin cannot provide a handle for the font.
        This assumes that only one font context is active at a moment.
    */
    ufst_common_font_data *d = (ufst_common_font_data *)ff->server_font_data;
    const double scale = F_ONE;
    double hx, hy;
    FAPI_retcode code;
    bool use_XL_format = ff->is_mtx_skipped;
    FSA_FROM_SERVER;

    if (ff->is_cid && ff->is_type1 && ff->font_file_path == NULL && 
        (dc == FAPI_TOPLEVEL_BEGIN || dc == FAPI_TOPLEVEL_COMPLETE)) {
	/* Don't need any processing for the top level font of a non-disk CIDFontType 0. 
	   See comment in FAPI_prepare_font.
	   Will do with its subfonts individually. 
	 */
	return 0; 
    }
    ff->need_decrypt = 1;
    if (d == 0) {
        if ((code = make_font_data(r, ff->font_file_path, ff, &d)) != 0)
	    return code;
        ff->server_font_data = d;
        prepare_typeface(r, d);
        if (ff->font_file_path != NULL || ff->is_type1) /* such fonts don't use RAW_GLYPH */
            choose_decoding(r, d, xlatmap);
    } else
        prepare_typeface(r, d);
    r->tran_xx = font_scale->matrix[0] / scale, r->tran_xy = font_scale->matrix[1] / scale;
    r->tran_yx = font_scale->matrix[2] / scale, r->tran_yy = font_scale->matrix[3] / scale;
    hx = hypot(r->tran_xx, r->tran_xy), hy = hypot(r->tran_yx, r->tran_yy);
    fc->xspot     = F_ONE;
    fc->yspot     = F_ONE;
    fc->fc_type   = FC_MAT2_TYPE;
    fc->s.m2.m[0] = (int)((double)font_scale->matrix[0] / hx + 0.5); 
    fc->s.m2.m[1] = (int)((double)font_scale->matrix[1] / hx + 0.5);
    fc->s.m2.m[2] = (int)((double)font_scale->matrix[2] / hy + 0.5);
    fc->s.m2.m[3] = (int)((double)font_scale->matrix[3] / hy + 0.5);
    fc->s.m2.matrix_scale = 16;
    fc->s.m2.xworld_res = font_scale->HWResolution[0] >> 16;
    fc->s.m2.yworld_res = font_scale->HWResolution[1] >> 16;
    fc->s.m2.world_scale = 0;
    fc->s.m2.point_size   = (int)(hy * 8 + 0.5); /* 1/8ths of pixels */
    fc->s.m2.set_size     = (int)(hx * 8 + 0.5);
    fc->numXsubpixels = font_scale->subpixels[0];
    fc->numYsubpixels = font_scale->subpixels[1];
    fc->alignment = (font_scale->align_to_pixels ? GAGG : GAPP);
    fc->ExtndFlags = 0;
    if (d->font_type == FC_TT_TYPE)
	fc->ssnum = USER_CMAP;
    else if (d->font_type == FC_FCO_TYPE) {
	fc->ssnum = UNICODE;
    } else
	fc->ExtndFlags = EF_NOSYMSETMAP; 
    fc->ExtndFlags |= EF_SUBSTHOLLOWBOX_TYPE;
    fc->format      |= FC_NON_Z_WIND;   /* NON_ZERO Winding required for TrueType */
    fc->format      |= FC_INCHES_TYPE;  /* output in units per inch */
    fc->user_platID = d->platformId;
    fc->user_specID = d->specificId;
    if (use_XL_format)
	fc->ExtndFlags |= EF_XLFONT_TYPE;
    if (ff->is_vertical)
        fc->ExtndFlags |= EF_UFSTVERT_TYPE;
    fc->dl_ssnum = (d->specificId << 4) | d->platformId;
    fc->ttc_index   = ff->subfont;
    r->callback_error = 0;
    code = CGIFfont(FSA fc);
    if (r->callback_error != 0)
	return r->callback_error;
    return code;
}

private FAPI_retcode get_decodingID(FAPI_server *server, FAPI_font *ff, const char **decodingID_result)
{   fapi_ufst_server *r = If_to_I(server);
    ufst_common_font_data *d = (ufst_common_font_data *)r->fc.font_hdr - 1;

    *decodingID_result = d->decodingID;
    return 0;
}

private FAPI_retcode get_font_bbox(FAPI_server *server, FAPI_font *ff, int BBox[4])
{   fapi_ufst_server *r = If_to_I(server);
    SW16 VLCPower = 0;
    int code;
    FSA_FROM_SERVER;

    if ((code = CGIFbound_box(FSA BBox, &VLCPower)) < 0)
	return code;
    /*  UFST expands bbox for internal needs, and retrives the expanded bbox.
        We believe it's bug in UFST.
        Now we collapse it back to the correct size :
    */
    BBox[0] += 2;
    BBox[1] += 2;
    BBox[2] -= 2;
    BBox[3] -= 2;
    BBox[0] >>= VLCPower;
    BBox[1] >>= VLCPower;
    BBox[2] >>= VLCPower;
    BBox[3] >>= VLCPower;
    return 0;
}

private FAPI_retcode get_font_proportional_feature(FAPI_server *server, FAPI_font *ff, bool *bProportional)
{   fapi_ufst_server *r = If_to_I(server);
    FSA_FROM_SERVER;

    *bProportional = false;
    if (ff->font_file_path == NULL || ff->is_type1)
        return 0;
#if TT_ROM || TT_DISK
    { 
	UB8 buf[74];
	UL32 length = sizeof(buf);

    if (CGIFtt_query(FSA (UB8 *)ff->font_file_path, *(UL32 *)"OS/2", (UW16)ff->subfont, &length, buf) != 0)
        return 0; /* No OS/2 table - no chance to get the info. Use default == false. */
    *bProportional = (buf[35] == 9);
    }
#endif
    return 0;
}

private inline void make_asciiz_char_name(char *buf, int buf_length, FAPI_char_ref *c)
{   int len = min(buf_length - 1, c->char_name_length);

    memcpy(buf, c->char_name, len);
    buf[len] = 0;
}

#define MAX_CHAR_NAME_LENGTH 30

private FAPI_retcode can_retrieve_char_by_name(FAPI_server *server, FAPI_font *ff, FAPI_char_ref *c, int *result)
{   fapi_ufst_server *r = If_to_I(server);
    FSA_FROM_SERVER;

    *result = 0;
    switch (r->fc.format & FC_FONTTYPE_MASK) {
        case FC_PST1_TYPE : 
            *result = 1; 
            break;
        case FC_TT_TYPE : 
            break;
    }
    return 0;
}

private FAPI_retcode can_replace_metrics(FAPI_server *server, FAPI_font *ff, FAPI_char_ref *c, int *result)
{   *result = (!ff->is_type1 && ff->font_file_path == NULL &&
	       c->metrics_scale == 0 && c->metrics_type == FAPI_METRICS_REPLACE);
    return 0;
}

private void release_glyphs(fapi_ufst_server *r, ufst_common_font_data *d)
{   while (d->glyphs != 0) {
        pcleo_glyph_list_elem *e = d->glyphs;
        d->glyphs = e->next;
        r->client_mem.free(&r->client_mem, e, "PCLEO char");
    }
}

private FAPI_retcode get_char_width(FAPI_server *server, FAPI_font *ff, FAPI_char_ref *c, FAPI_metrics *metrics)
{   fapi_ufst_server *r = If_to_I(server);
    UW16 buffer[2];
    UW16 cc = (UW16)c->char_code;
    WIDTH_LIST_INPUT_ENTRY li[1];
    char PSchar_name[MAX_CHAR_NAME_LENGTH];
    int code;
    FSA_FROM_SERVER;

    make_asciiz_char_name(PSchar_name, sizeof(PSchar_name), c);
    r->ff = ff;
    CGIFchIdptr(FSA &cc, PSchar_name);
    li[0]. CharType.IF_cgnum = cc;
    if ((code = CGIFwidth(FSA li, 1, 4, buffer)) != 0)
	return code;
    r->ff = 0;
    release_glyphs(r, (ufst_common_font_data *)ff->server_font_data);
    metrics->escapement = buffer[0];
    metrics->em_x = metrics->em_y = buffer[1];
    return 0;
}

private int export_outline(fapi_ufst_server *r, PIFOUTLINE pol, FAPI_path *p)
{   POUTLINE_CHAR outchar;
    SW16 num_contrs,num_segmts;
    LPSB8 segment;
    PINTRVECTOR points;
    SW16  i,j;

    if (pol == NULL)
        return 0;
    p->shift += r->If.frac_shift + pol->VLCpower;
    outchar = &pol->ol;
    num_contrs = outchar->num_loops;
    for(i = 0; i<num_contrs; i++) {
     	num_segmts = outchar->loop[i].num_segmts;
        segment = (LPSB8)((LPSB8)(outchar->loop) + outchar->loop[i].segmt_offset);
        points = (PINTRVECTOR)((LPSB8)(outchar->loop) + outchar->loop[i].coord_offset);
        for(j=0; j<num_segmts; j++) {
	    int code;

            if(*segment == 0x00) {
             	if ((code = p->moveto(p, points->x, points->y)) != 0)
		    return code;
                points++;
            } else if (*segment == 0x01) {
		if ((code = p->lineto(p, points->x, points->y)) != 0)
		    return code;
                points++;
            } else if (*segment == 0x02) {
                points+=2;
                return e_invalidfont; /* This must not happen */
            } else if (*segment == 0x03) {
		if ((code = p->curveto(p, points[0].x, points[0].y,
					points[1].x, points[1].y,
					points[2].x, points[2].y)) < 0)
		    return code;
                points+=3;
            } else
                return e_invalidfont; /* This must not happen */
            segment++;
        }
    }
    return 0;
}

private inline void set_metrics(fapi_ufst_server *r, FAPI_metrics *metrics, SL32 design_bbox[4], SW16 design_escapement, SW16 du_emx, SW16 du_emy)
{   metrics->escapement = design_escapement; 
    metrics->em_x = du_emx;
    metrics->em_y = du_emy;
    metrics->bbox_x0 = design_bbox[0];
    metrics->bbox_y0 = design_bbox[1];
    metrics->bbox_x1 = design_bbox[2];
    metrics->bbox_y1 = design_bbox[3];
}

private FAPI_retcode get_char(fapi_ufst_server *r, FAPI_font *ff, FAPI_char_ref *c, FAPI_path *p, FAPI_metrics *metrics, UW16 format)
{   UW16 code;
    UW16 cc = (UW16)c->char_code;
    SL32 design_bbox[4];
    char PSchar_name[MAX_CHAR_NAME_LENGTH];
    MEM_HANDLE result;
    ufst_common_font_data *d = (ufst_common_font_data *)ff->server_font_data;
    SW16 design_escapement;
    SW16 du_emx, du_emy;
    FSA_FROM_SERVER;

    memset(metrics, 0, sizeof(*metrics));
    metrics->bbox_x1 = -1;
    make_asciiz_char_name(PSchar_name, sizeof(PSchar_name), c);
    CGIFchIdptr(FSA &cc, PSchar_name); /* fixme : Likely only FC_PST1_TYPE needs it. */
    {   /* hack : Changing UFST internal data. Change to r->fc doesn't help, 
	   because UFST thinks that the "outline/raster" is a property of current font. */
        pIFS->fcCur.format &= ~FC_OUTPUT_MASK;
        pIFS->fcCur.format |= format;
    }
    r->bRaster = false;
    r->ff = ff;
    r->callback_error = 0;
    r->sb_x = c->sb_x;
    r->aw_x = c->aw_x;
    r->metrics_type = c->metrics_type;
    if (d->font_type == FC_FCO_TYPE && r->fc.ExtndFlags & EF_SUBSTHOLLOWBOX_TYPE) {
	if (c->char_name != NULL && c->char_name_length == 7 &&
		!memcmp(c->char_name, ".notdef", 7)) {
	    /* With EF_SUBSTHOLLOWBOX_TYPE and FCO,
	       UFST paints a hollow box insted .notdef .
	       For Adobe compatibility we substitute a space,
	       because Adobe Type 1 fonts define .notdef as a space . */
	    cc = 32;
	}
    }
#if !UFST_REENTRANT
    static_server_ptr_for_ufst_callback = r;
#endif
    code = CGIFchar_handle(FSA cc, &result, (SW16)0);
    if (code == ERR_find_cgnum) {
        /* There is no such char in the font, try the glyph 0 (notdef) : */
        const void *client_char_data = ff->char_data;
        UW16 c1 = 0, ssnum = pIFS->fcCur.ssnum;

	if (d->font_type == FC_FCO_TYPE) {
	    /* EF_SUBSTHOLLOWBOX_TYPE must work against it. 
	       Ensure the plugin plug__xi.fco is loaded. */
	    /* fixme : Due to unknown reason EF_SUBSTHOLLOWBOX_TYPE
	       doesn't work for Symbol, Dingbats, Wingdings.
	       hack : render the space character. */
	    c1 = 32;
	} else {
	    /* hack : Changing UFST internal data - see above. */
	    pIFS->fcCur.ssnum = RAW_GLYPH;
	}
        r->callback_error = 0;
        ff->char_data = NULL;
        CGIFchIdptr(FSA &c1, (char *)".notdef");
	code = CGIFchar_handle(FSA c1, &result, (SW16)0);
        pIFS->fcCur.ssnum = ssnum;
        ff->char_data = client_char_data;
    }
#if !UFST_REENTRANT
    static_server_ptr_for_ufst_callback = 0;
#endif
    r->ff = 0;
    release_glyphs(r, (ufst_common_font_data *)ff->server_font_data);
    if (code != ERR_fixed_space && code != 0)
	return code;
    if (r->callback_error != 0)
	return r->callback_error;
    if (format == FC_BITMAP_TYPE) {
        IFBITMAP *pbm = (IFBITMAP *)result;

        design_escapement = pbm->escapement;
	du_emx = pbm->du_emx;
	du_emy = pbm->du_emy;
        r->char_data = pbm;
        r->bRaster = true;
    } else {
        IFOUTLINE *pol = (IFOUTLINE *)result;

        design_escapement = pol->escapement;
	du_emx = pol->du_emx;
	du_emy = pol->du_emy;
        r->char_data = (IFOUTLINE *)result;
    }
#if 1 /* UFST 5.0 */
    if (USBOUNDBOX && d->font_type == FC_FCO_TYPE) {
	if (pIFS->USBBOXorigScaleFactor /* fixme : Must we check this ? */
	    && pIFS->USBBOXorigScaleFactor != pIFS->USBBOXscaleFactor) { 
	    /* See fco_make_gaso_and_stats in fc_if.c . Debugged with hollow box in Helvetica. */
	    /* Fixme : this looses a precision, an UFST bug has been reported. */
	    int w = pIFS->USBBOXorigScaleFactor / 2;

	    design_bbox[0] = pIFS->USBBOXxmin * pIFS->USBBOXscaleFactor / pIFS->USBBOXorigScaleFactor;
	    design_bbox[1] = pIFS->USBBOXymin * pIFS->USBBOXscaleFactor / pIFS->USBBOXorigScaleFactor;
	    design_bbox[2] = (pIFS->USBBOXxmax * pIFS->USBBOXscaleFactor + w) / pIFS->USBBOXorigScaleFactor;
	    design_bbox[3] = (pIFS->USBBOXymax * pIFS->USBBOXscaleFactor + w) / pIFS->USBBOXorigScaleFactor;
	} else {
	    design_bbox[0] = pIFS->USBBOXxmin;
	    design_bbox[1] = pIFS->USBBOXymin;
	    design_bbox[2] = pIFS->USBBOXxmax;
	    design_bbox[3] = pIFS->USBBOXymax;
	}
    } else {
	/* fixme: UFST 5.0 doesn't provide this data. 
	   Stubbing with Em box. 
	   Non-FCO fonts may be cropped if a glyph goes outside Em box 
	   (or occupy negative coordinates, such as 'y'.).
	   Non-FCO fonts may be uncached if Em box is much bigger than the glyph.
	 */
	design_bbox[0] = 0;
	design_bbox[1] = 0;
	design_bbox[2] = du_emx;
	design_bbox[3] = du_emy;
    }
#endif
    {	/* UFST performs a dual rounding of the glyph origin : first
	   the scaled glyph design origin is rounded to pixels with floor(x + 0.5),
	   second the glyph position is rounded to pixels with floor(x + 0.5).
	   Ghostscript rounds with floor(x) due to the pixel-center-inside rule. 
	   
	   A right way would be to specify the half pixel offset to the glyph
	   origin for the rendering glyph, but UFST has no interface for doing that.
	   Instead that, to prevent a possible cropping while copying a glyph to cache cell,
	   we expand the design bbox in a value of a pixel size.
	   We could not determine the necessary expansion theoretically,
	   and choosen expansion coefficients empirically,
	   which appears equal to 2 pixels.

	   fixme: Actually the expansion is the FONTCONTEXT property,
	   so it could be computed at once when the scaled font is created.
	 */
	const double expansion_x = 2, expansion_y = 2; /* pixels */ /* adesso5.pdf */
	const double XX = r->tran_xx * r->fc.s.m2.xworld_res / 72 / du_emx;
	const double XY = r->tran_xy * r->fc.s.m2.yworld_res / 72 / du_emy;
	const double YX = r->tran_yx * r->fc.s.m2.xworld_res / 72 / du_emx;
	const double YY = r->tran_yy * r->fc.s.m2.yworld_res / 72 / du_emy;
	const double det = XX * YY - XY * YX;
	const double deta = det < 0 ? -det : det;

	if (deta > 0.0000000001) {
	    const double xx =  YY / det, xy = -XY / det;
	    const double yx = -YX / det, yy =  XX / det;
	    const double dx = -(expansion_x * xx + expansion_y * xy);
	    const double dy = -(expansion_x * yx + expansion_y * yy);
	    const SL32 dxa = (SL32)((dx < 0 ? -dx : dx) + 0.5);
	    const SL32 dya = (SL32)((dy < 0 ? -dy : dy) + 0.5);
	    
	    design_bbox[0] -= dxa;
	    design_bbox[1] -= dya;
	    design_bbox[2] += dxa;
	    design_bbox[3] += dya;
	}
    }
    set_metrics(r, metrics, design_bbox, design_escapement, du_emx, du_emy);
    if (code == ERR_fixed_space)
        release_char_data_inline(r);
    return 0;
}

private FAPI_retcode get_char_outline_metrics(FAPI_server *server, FAPI_font *ff, FAPI_char_ref *c, FAPI_metrics *metrics)
{   fapi_ufst_server *r = If_to_I(server);

    release_char_data_inline(r);
    return get_char(r, ff, c, NULL, metrics, FC_CUBIC_TYPE);
    /*	UFST cannot render enough metrics information without generating raster or outline. 
	r->char_data keeps an outline after calling this function.
    */
}

private FAPI_retcode get_char_outline(FAPI_server *server, FAPI_path *p)
{   fapi_ufst_server *r = If_to_I(server);

    return export_outline(r, (IFOUTLINE *)r->char_data, p);
}

private FAPI_retcode get_char_raster_metrics(FAPI_server *server, FAPI_font *ff, FAPI_char_ref *c, FAPI_metrics *metrics)
{   fapi_ufst_server *r = If_to_I(server);
    int code;

    release_char_data_inline(r);
    code = get_char(r, ff, c, NULL, metrics, FC_BITMAP_TYPE);
    if (code == ERR_bm_buff || code == ERR_bm_too_big) /* Too big character ? */
        return e_limitcheck;
    return code;
    /*	UFST cannot render enough metrics information without generating raster or outline. 
	r->char_data keeps a raster after calling this function.
    */
}

private FAPI_retcode get_char_raster(FAPI_server *server, FAPI_raster *rast)
{   fapi_ufst_server *r = If_to_I(server);

    if (!r->bRaster)
        return e_limitcheck;
    else if (r->char_data == NULL) {
	rast->height = rast->width = rast->line_step = 0;
	rast->p = 0;
    } else {
        IFBITMAP *pbm = (IFBITMAP *)r->char_data;
        rast->p = pbm->bm;
        rast->height = pbm->top_indent + pbm->black_depth;
        rast->width = pbm->left_indent + pbm->black_width;
        rast->line_step = pbm->width;
	rast->left_indent = pbm->left_indent;
	rast->top_indent = pbm->top_indent;
	rast->black_width = pbm->black_width;
	rast->black_height = pbm->black_depth;
        if (rast->width != 0) {
            rast->orig_x = pbm->xorigin;
            rast->orig_y = pbm->yorigin;
        } else
            rast->orig_x = rast->orig_y = 0;
    }
    return 0;
}

private FAPI_retcode release_char_data(FAPI_server *server)
{   fapi_ufst_server *r = If_to_I(server);

    release_char_data_inline(r);
    return 0;
}

private void release_fco(fapi_ufst_server *r, SW16 fcHandle)
{   
    fco_list_elem **e;

    if(gx_UFST_find_static_fco_handle(fcHandle) != NULL)
	return;
    for (e = &r->fco_list; *e != 0; )
        if ((*e)->fcHandle == fcHandle && (--(*e)->open_count) == 0) {
            fco_list_elem *ee = *e;
	    FSA_FROM_SERVER;

            *e = ee->next;
            CGIFfco_Close(FSA ee->fcHandle);
            r->client_mem.free(&r->client_mem, ee->file_path, "fco_file_path");
            r->client_mem.free(&r->client_mem, ee, "fco_list_elem");
        } else
            e = &(*e)->next;
}

private FAPI_retcode release_typeface(FAPI_server *server, void *font_data)
{   fapi_ufst_server *r = If_to_I(server);
    ufst_common_font_data *d;
    FAPI_retcode code = 0;
    FSA_FROM_SERVER;

    release_char_data_inline(r);
    if (font_data == 0)
        return 0;
    d = (ufst_common_font_data *)font_data;
    prepare_typeface(r, d);
    if (d->is_disk_font)
        code = CGIFhdr_font_purge(FSA &r->fc);
    else
        code = CGIFfont_purge(FSA &r->fc);
    release_glyphs(r, d);
    release_fco(r, (SW16)(d->font_id >> 16));
    r->client_mem.free(&r->client_mem, font_data, "ufst font data");
    return code;
}

/* --------------------- The plugin definition : ------------------------- */


private void gs_fapiufst_finit(i_plugin_instance *instance, i_plugin_client_memory *mem);

private const i_plugin_descriptor ufst_descriptor = {
    "FAPI",
    "UFST",
    gs_fapiufst_finit
};

private const FAPI_server If0 = {
    {   &ufst_descriptor
    },
    16, /* frac_shift */
    {gs_no_id},
    {0},
    ensure_open,
    get_scaled_font,
    get_decodingID,
    get_font_bbox,
    get_font_proportional_feature,
    can_retrieve_char_by_name,
    can_replace_metrics,
    get_char_width,
    get_char_raster_metrics,
    get_char_raster,
    get_char_outline_metrics,
    get_char_outline,
    release_char_data,
    release_typeface
};

plugin_instantiation_proc(gs_fapiufst_instantiate);      /* check prototype */

int gs_fapiufst_instantiate(i_plugin_client_memory *client_mem, i_plugin_instance **p_instance)
{   fapi_ufst_server *r = (fapi_ufst_server *)client_mem->alloc(client_mem, sizeof(fapi_ufst_server), "fapi_ufst_server");

    if (r == 0)
        return e_Fatal;
    memset(r, 0, sizeof(*r));
    r->If = If0;
    r->client_mem = *client_mem;
    *p_instance = &r->If.ig;
    return 0;
}

private void gs_fapiufst_finit(i_plugin_instance *this, i_plugin_client_memory *mem)
{   fapi_ufst_server *r = (fapi_ufst_server *)this;
    FSA_FROM_SERVER;

    if (r->If.ig.d != &ufst_descriptor)
        return; /* safety */
#if 0 /* Disabled against a reentrancy problem 
	 in a single language build for host-based applications. */
    gx_set_UFST_Callbacks(NULL, NULL, NULL);
#endif
    release_char_data_inline(r);
    if (r->bInitialized && !r->ufst_is_singleton)
	gx_UFST_fini();
    mem->free(mem, r, "fapi_ufst_server");
}
