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path: root/render/glyph.c
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/*
 *
 * Copyright © 2000 SuSE, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of SuSE not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  SuSE makes no representations about the
 * suitability of this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 *
 * SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE
 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Author:  Keith Packard, SuSE, Inc.
 */

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#ifdef HAVE_SHA1_IN_LIBMD /* Use libmd for SHA1 */
# include <sha1.h>
#else /* Use OpenSSL's libcrypto */
# include <stddef.h>  /* buggy openssl/sha.h wants size_t */
# include <openssl/sha.h>
#endif

#include "misc.h"
#include "scrnintstr.h"
#include "os.h"
#include "regionstr.h"
#include "validate.h"
#include "windowstr.h"
#include "input.h"
#include "resource.h"
#include "colormapst.h"
#include "cursorstr.h"
#include "dixstruct.h"
#include "gcstruct.h"
#include "servermd.h"
#include "picturestr.h"
#include "glyphstr.h"
#include "mipict.h"

/*
 * From Knuth -- a good choice for hash/rehash values is p, p-2 where
 * p and p-2 are both prime.  These tables are sized to have an extra 10%
 * free to avoid exponential performance degradation as the hash table fills
 */
static GlyphHashSetRec glyphHashSets[] = {
    { 32,		43,		41        },
    { 64,		73,		71        },
    { 128,		151,		149       },
    { 256,		283,		281       },
    { 512,		571,		569       },
    { 1024,		1153,		1151      },
    { 2048,		2269,		2267      },
    { 4096,		4519,		4517      },
    { 8192,		9013,		9011      },
    { 16384,		18043,		18041     },
    { 32768,		36109,		36107     },
    { 65536,		72091,		72089     },
    { 131072,		144409,		144407    },
    { 262144,		288361,		288359    },
    { 524288,		576883,		576881    },
    { 1048576,		1153459,	1153457   },
    { 2097152,		2307163,	2307161   },
    { 4194304,		4613893,	4613891   },
    { 8388608,		9227641,	9227639   },
    { 16777216,		18455029,	18455027  },
    { 33554432,		36911011,	36911009  },
    { 67108864,		73819861,	73819859  },
    { 134217728,	147639589,	147639587 },
    { 268435456,	295279081,	295279079 },
    { 536870912,	590559793,	590559791 }
};

#define NGLYPHHASHSETS	(sizeof(glyphHashSets)/sizeof(glyphHashSets[0]))

static const CARD8	glyphDepths[GlyphFormatNum] = { 1, 4, 8, 16, 32 };

static GlyphHashRec	globalGlyphs[GlyphFormatNum];

static void
FreeGlyphPrivates (GlyphPtr glyph)
{
    dixFreePrivates(glyph->devPrivates);
    glyph->devPrivates = NULL;
}

void
GlyphUninit (ScreenPtr pScreen)
{
    PictureScreenPtr ps = GetPictureScreen (pScreen);
    GlyphPtr	     glyph;
    int		     fdepth, i;

    for (fdepth = 0; fdepth < GlyphFormatNum; fdepth++)
    {
	if (!globalGlyphs[fdepth].hashSet)
	    continue;
	
	for (i = 0; i < globalGlyphs[fdepth].hashSet->size; i++)
	{
	    glyph = globalGlyphs[fdepth].table[i].glyph;
	    if (glyph && glyph != DeletedGlyph)
	    {
		(*ps->UnrealizeGlyph) (pScreen, glyph);
		FreeGlyphPrivates(glyph);
	    }
	}
    }

    for (fdepth = 0; fdepth < GlyphFormatNum; fdepth++)
    {
	if (!globalGlyphs[fdepth].hashSet)
	    continue;
	
	for (i = 0; i < globalGlyphs[fdepth].hashSet->size; i++)
	    glyph = globalGlyphs[fdepth].table[i].glyph;    
    }
}

GlyphHashSetPtr
FindGlyphHashSet (CARD32 filled)
{
    int	i;

    for (i = 0; i < NGLYPHHASHSETS; i++)
	if (glyphHashSets[i].entries >= filled)
	    return &glyphHashSets[i];
    return 0;
}

GlyphRefPtr
FindGlyphRef (GlyphHashPtr	hash,
	      CARD32		signature,
	      Bool		match,
	      unsigned char	sha1[20])
{
    CARD32	elt, step, s;
    GlyphPtr	glyph;
    GlyphRefPtr	table, gr, del;
    CARD32	tableSize = hash->hashSet->size;

    table = hash->table;
    elt = signature % tableSize;
    step = 0;
    del = 0;
    for (;;)
    {
	gr = &table[elt];
	s = gr->signature;
	glyph = gr->glyph;
	if (!glyph)
	{
	    if (del)
		gr = del;
	    break;
	}
	if (glyph == DeletedGlyph)
	{
	    if (!del)
		del = gr;
	    else if (gr == del)
		break;
	}
	else if (s == signature &&
		 (!match || 
		  memcmp (glyph->sha1, sha1, 20) == 0))
	{
	    break;
	}
	if (!step)
	{
	    step = signature % hash->hashSet->rehash;
	    if (!step)
		step = 1;
	}
	elt += step;
	if (elt >= tableSize)
	    elt -= tableSize;
    }
    return gr;
}

int
HashGlyph (xGlyphInfo    *gi,
	   CARD8	 *bits,
	   unsigned long size,
	   unsigned char sha1[20])
{
#ifdef HAVE_SHA1_IN_LIBMD /* Use libmd for SHA1 */
    SHA1_CTX ctx;

    SHA1Init (&ctx);
    SHA1Update (&ctx, gi, sizeof (xGlyphInfo));
    SHA1Update (&ctx, bits, size);
    SHA1Final (sha1, &ctx);
#else /* Use OpenSSL's libcrypto */
    SHA_CTX ctx;
    int success;

    success = SHA1_Init (&ctx);
    if (! success)
	return BadAlloc;

    success = SHA1_Update (&ctx, gi, sizeof (xGlyphInfo));
    if (! success)
	return BadAlloc;

    success = SHA1_Update (&ctx, bits, size);
    if (! success)
	return BadAlloc;

    success = SHA1_Final (sha1, &ctx);
    if (! success)
	return BadAlloc;
#endif

    return Success;
}

GlyphPtr
FindGlyphByHash (unsigned char sha1[20], int format)
{
    GlyphRefPtr gr;
    CARD32 signature = *(CARD32 *) sha1;

    gr = FindGlyphRef (&globalGlyphs[format],
		       signature, TRUE, sha1);

    if (gr->glyph && gr->glyph != DeletedGlyph)
	return gr->glyph;
    else
	return NULL;
}

#ifdef CHECK_DUPLICATES
void
DuplicateRef (GlyphPtr glyph, char *where)
{
    ErrorF ("Duplicate Glyph 0x%x from %s\n", glyph, where);
}

void
CheckDuplicates (GlyphHashPtr hash, char *where)
{
    GlyphPtr	g;
    int		i, j;

    for (i = 0; i < hash->hashSet->size; i++)
    {
	g = hash->table[i].glyph;
	if (!g || g == DeletedGlyph)
	    continue;
	for (j = i + 1; j < hash->hashSet->size; j++)
	    if (hash->table[j].glyph == g)
		DuplicateRef (g, where);
    }
}
#else
#define CheckDuplicates(a,b)
#define DuplicateRef(a,b)
#endif

static void
FreeGlyphPicture(GlyphPtr glyph)
{
    PictureScreenPtr ps;
    int i;

    for (i = 0; i < screenInfo.numScreens; i++)
    {
        ScreenPtr pScreen = screenInfo.screens[i];

        if (GlyphPicture(glyph)[i])
            FreePicture ((pointer) GlyphPicture (glyph)[i], 0);

        ps = GetPictureScreenIfSet (pScreen);
        if (ps)
            (*ps->UnrealizeGlyph) (pScreen, glyph);
    }
}


void
FreeGlyph (GlyphPtr glyph, int format)
{
    CheckDuplicates (&globalGlyphs[format], "FreeGlyph");
    if (--glyph->refcnt == 0)
    {
	GlyphRefPtr      gr;
	int	         i;
	int	         first;
	CARD32		 signature;

	first = -1;
	for (i = 0; i < globalGlyphs[format].hashSet->size; i++)
	    if (globalGlyphs[format].table[i].glyph == glyph)
	    {
		if (first != -1)
		    DuplicateRef (glyph, "FreeGlyph check");
		first = i;
	    }

	signature = *(CARD32 *) glyph->sha1;
	gr = FindGlyphRef (&globalGlyphs[format], signature,
			   TRUE, glyph->sha1);
	if (gr - globalGlyphs[format].table != first)
	    DuplicateRef (glyph, "Found wrong one");
	if (gr->glyph && gr->glyph != DeletedGlyph)
	{
	    gr->glyph = DeletedGlyph;
	    gr->signature = 0;
	    globalGlyphs[format].tableEntries--;
	}

	FreeGlyphPicture(glyph);
	FreeGlyphPrivates(glyph);
	xfree (glyph);
    }
}

void
AddGlyph (GlyphSetPtr glyphSet, GlyphPtr glyph, Glyph id)
{
    GlyphRefPtr	    gr;
    CARD32	    signature;

    CheckDuplicates (&globalGlyphs[glyphSet->fdepth], "AddGlyph top global");
    /* Locate existing matching glyph */
    signature = *(CARD32 *) glyph->sha1;
    gr = FindGlyphRef (&globalGlyphs[glyphSet->fdepth], signature,
		       TRUE, glyph->sha1);
    if (gr->glyph && gr->glyph != DeletedGlyph && gr->glyph != glyph)
    {
	FreeGlyphPicture(glyph);
	FreeGlyphPrivates(glyph);
	xfree (glyph);
	glyph = gr->glyph;
    }
    else if (gr->glyph != glyph)
    {
	gr->glyph = glyph;
	gr->signature = signature;
	globalGlyphs[glyphSet->fdepth].tableEntries++;
    }
    
    /* Insert/replace glyphset value */
    gr = FindGlyphRef (&glyphSet->hash, id, FALSE, 0);
    ++glyph->refcnt;
    if (gr->glyph && gr->glyph != DeletedGlyph)
	FreeGlyph (gr->glyph, glyphSet->fdepth);
    else
	glyphSet->hash.tableEntries++;
    gr->glyph = glyph;
    gr->signature = id;
    CheckDuplicates (&globalGlyphs[glyphSet->fdepth], "AddGlyph bottom");
}

Bool
DeleteGlyph (GlyphSetPtr glyphSet, Glyph id)
{
    GlyphRefPtr     gr;
    GlyphPtr	    glyph;

    gr = FindGlyphRef (&glyphSet->hash, id, FALSE, 0);
    glyph = gr->glyph;
    if (glyph && glyph != DeletedGlyph)
    {
	gr->glyph = DeletedGlyph;
	glyphSet->hash.tableEntries--;
	FreeGlyph (glyph, glyphSet->fdepth);
	return TRUE;
    }
    return FALSE;
}

GlyphPtr
FindGlyph (GlyphSetPtr glyphSet, Glyph id)
{
    GlyphPtr        glyph;

    glyph = FindGlyphRef (&glyphSet->hash, id, FALSE, 0)->glyph;
    if (glyph == DeletedGlyph)
	glyph = 0;
    return glyph;
}

GlyphPtr
AllocateGlyph (xGlyphInfo *gi, int fdepth)
{
    PictureScreenPtr ps;
    int		     size;
    GlyphPtr	     glyph;
    int		     i;

    size = screenInfo.numScreens * sizeof (PicturePtr);
    glyph = (GlyphPtr) xalloc (size + sizeof (GlyphRec));
    if (!glyph)
	return 0;
    glyph->refcnt = 0;
    glyph->size = size + sizeof (xGlyphInfo);
    glyph->info = *gi;
    glyph->devPrivates = NULL;

    for (i = 0; i < screenInfo.numScreens; i++)
    {
	GlyphPicture(glyph)[i] = NULL;
	ps = GetPictureScreenIfSet (screenInfo.screens[i]);

	if (ps)
	{
	    if (!(*ps->RealizeGlyph) (screenInfo.screens[i], glyph))
		goto bail;
	}
    }
    
    return glyph;

bail:
    while (i--)
    {
	ps = GetPictureScreenIfSet (screenInfo.screens[i]);
	if (ps)
	    (*ps->UnrealizeGlyph) (screenInfo.screens[i], glyph);
    }

    FreeGlyphPrivates(glyph);
    xfree (glyph);
    return 0;
}
    
Bool
AllocateGlyphHash (GlyphHashPtr hash, GlyphHashSetPtr hashSet)
{
    hash->table = xcalloc (hashSet->size, sizeof (GlyphRefRec));
    if (!hash->table)
	return FALSE;
    hash->hashSet = hashSet;
    hash->tableEntries = 0;
    return TRUE;
}

Bool
ResizeGlyphHash (GlyphHashPtr hash, CARD32 change, Bool global)
{
    CARD32	    tableEntries;
    GlyphHashSetPtr hashSet;
    GlyphHashRec    newHash;
    GlyphRefPtr	    gr;
    GlyphPtr	    glyph;
    int		    i;
    int		    oldSize;
    CARD32	    s;

    tableEntries = hash->tableEntries + change;
    hashSet = FindGlyphHashSet (tableEntries);
    if (hashSet == hash->hashSet)
	return TRUE;
    if (global)
	CheckDuplicates (hash, "ResizeGlyphHash top");
    if (!AllocateGlyphHash (&newHash, hashSet))
	return FALSE;
    if (hash->table)
    {
	oldSize = hash->hashSet->size;
	for (i = 0; i < oldSize; i++)
	{
	    glyph = hash->table[i].glyph;
	    if (glyph && glyph != DeletedGlyph)
	    {
		s = hash->table[i].signature;
		gr = FindGlyphRef (&newHash, s, global, glyph->sha1);
		gr->signature = s;
		gr->glyph = glyph;
		++newHash.tableEntries;
	    }
	}
	xfree (hash->table);
    }
    *hash = newHash;
    if (global)
	CheckDuplicates (hash, "ResizeGlyphHash bottom");
    return TRUE;
}

Bool
ResizeGlyphSet (GlyphSetPtr glyphSet, CARD32 change)
{
    return (ResizeGlyphHash (&glyphSet->hash, change, FALSE) &&
	    ResizeGlyphHash (&globalGlyphs[glyphSet->fdepth], change, TRUE));
}
			    
GlyphSetPtr
AllocateGlyphSet (int fdepth, PictFormatPtr format)
{
    GlyphSetPtr	glyphSet;
    int size;
    
    if (!globalGlyphs[fdepth].hashSet)
    {
	if (!AllocateGlyphHash (&globalGlyphs[fdepth], &glyphHashSets[0]))
	    return FALSE;
    }

    size = sizeof (GlyphSetRec);
    glyphSet = xcalloc (1, size);
    if (!glyphSet)
	return FALSE;

    if (!AllocateGlyphHash (&glyphSet->hash, &glyphHashSets[0]))
    {
	xfree (glyphSet);
	return FALSE;
    }
    glyphSet->refcnt = 1;
    glyphSet->fdepth = fdepth;
    glyphSet->format = format;
    return glyphSet;	
}

int
FreeGlyphSet (pointer	value,
	      XID       gid)
{
    GlyphSetPtr	glyphSet = (GlyphSetPtr) value;
    
    if (--glyphSet->refcnt == 0)
    {
	CARD32	    i, tableSize = glyphSet->hash.hashSet->size;
	GlyphRefPtr table = glyphSet->hash.table;
	GlyphPtr    glyph;
    
	for (i = 0; i < tableSize; i++)
	{
	    glyph = table[i].glyph;
	    if (glyph && glyph != DeletedGlyph)
		FreeGlyph (glyph, glyphSet->fdepth);
	}
	if (!globalGlyphs[glyphSet->fdepth].tableEntries)
	{
	    xfree (globalGlyphs[glyphSet->fdepth].table);
	    globalGlyphs[glyphSet->fdepth].table = 0;
	    globalGlyphs[glyphSet->fdepth].hashSet = 0;
	}
	else
	    ResizeGlyphHash (&globalGlyphs[glyphSet->fdepth], 0, TRUE);
	xfree (table);
	dixFreePrivates(glyphSet->devPrivates);
	xfree (glyphSet);
    }
    return Success;
}

static void
GlyphExtents (int		nlist,
		GlyphListPtr	list,
		GlyphPtr	*glyphs,
		BoxPtr		extents)
{
    int		x1, x2, y1, y2;
    int		n;
    GlyphPtr	glyph;
    int		x, y;
    
    x = 0;
    y = 0;
    extents->x1 = MAXSHORT;
    extents->x2 = MINSHORT;
    extents->y1 = MAXSHORT;
    extents->y2 = MINSHORT;
    while (nlist--)
    {
	x += list->xOff;
	y += list->yOff;
	n = list->len;
	list++;
	while (n--)
	{
	    glyph = *glyphs++;
	    x1 = x - glyph->info.x;
	    if (x1 < MINSHORT)
		x1 = MINSHORT;
	    y1 = y - glyph->info.y;
	    if (y1 < MINSHORT)
		y1 = MINSHORT;
	    x2 = x1 + glyph->info.width;
	    if (x2 > MAXSHORT)
		x2 = MAXSHORT;
	    y2 = y1 + glyph->info.height;
	    if (y2 > MAXSHORT)
		y2 = MAXSHORT;
	    if (x1 < extents->x1)
		extents->x1 = x1;
	    if (x2 > extents->x2)
		extents->x2 = x2;
	    if (y1 < extents->y1)
		extents->y1 = y1;
	    if (y2 > extents->y2)
		extents->y2 = y2;
	    x += glyph->info.xOff;
	    y += glyph->info.yOff;
	}
    }
}

#define NeedsComponent(f) (PICT_FORMAT_A(f) != 0 && PICT_FORMAT_RGB(f) != 0)

void
CompositeGlyphs (CARD8		op,
		 PicturePtr	pSrc,
		 PicturePtr	pDst,
		 PictFormatPtr	maskFormat,
		 INT16		xSrc,
		 INT16		ySrc,
		 int		nlist,
		 GlyphListPtr	lists,
		 GlyphPtr	*glyphs)
{
    PictureScreenPtr	ps = GetPictureScreen(pDst->pDrawable->pScreen);

    ValidatePicture (pSrc);
    ValidatePicture (pDst);
    (*ps->Glyphs) (op, pSrc, pDst, maskFormat, xSrc, ySrc, nlist, lists, glyphs);
}

Bool
miRealizeGlyph (ScreenPtr pScreen,
		GlyphPtr  glyph)
{
    return TRUE;
}

void
miUnrealizeGlyph (ScreenPtr pScreen,
		  GlyphPtr  glyph)
{
}

void
miGlyphs (CARD8		op,
	  PicturePtr	pSrc,
	  PicturePtr	pDst,
	  PictFormatPtr	maskFormat,
	  INT16		xSrc,
	  INT16		ySrc,
	  int		nlist,
	  GlyphListPtr	list,
	  GlyphPtr	*glyphs)
{
    PicturePtr	pPicture;
    PixmapPtr   pMaskPixmap = 0;
    PicturePtr  pMask;
    ScreenPtr   pScreen = pDst->pDrawable->pScreen;
    int		width = 0, height = 0;
    int		x, y;
    int		xDst = list->xOff, yDst = list->yOff;
    int		n;
    GlyphPtr	glyph;
    int		error;
    BoxRec	extents = {0, 0, 0, 0};
    CARD32	component_alpha;

    if (maskFormat)
    {
	GCPtr	    pGC;
	xRectangle  rect;

	GlyphExtents (nlist, list, glyphs, &extents);

	if (extents.x2 <= extents.x1 || extents.y2 <= extents.y1)
	    return;
	width = extents.x2 - extents.x1;
	height = extents.y2 - extents.y1;
	pMaskPixmap = (*pScreen->CreatePixmap) (pScreen, width, height,
						maskFormat->depth,
						CREATE_PIXMAP_USAGE_SCRATCH);
	if (!pMaskPixmap)
	    return;
	component_alpha = NeedsComponent(maskFormat->format);
	pMask = CreatePicture (0, &pMaskPixmap->drawable,
			       maskFormat, CPComponentAlpha, &component_alpha,
			       serverClient, &error);
	if (!pMask)
	{
	    (*pScreen->DestroyPixmap) (pMaskPixmap);
	    return;
	}
	pGC = GetScratchGC (pMaskPixmap->drawable.depth, pScreen);
	ValidateGC (&pMaskPixmap->drawable, pGC);
	rect.x = 0;
	rect.y = 0;
	rect.width = width;
	rect.height = height;
	(*pGC->ops->PolyFillRect) (&pMaskPixmap->drawable, pGC, 1, &rect);
	FreeScratchGC (pGC);
	x = -extents.x1;
	y = -extents.y1;
    }
    else
    {
	pMask = pDst;
	x = 0;
	y = 0;
    }
    while (nlist--)
    {
	x += list->xOff;
	y += list->yOff;
	n = list->len;
	while (n--)
	{
	    glyph = *glyphs++;
	    pPicture = GlyphPicture (glyph)[pScreen->myNum];

	    if (pPicture)
	    {
		if (maskFormat)
		{
			CompositePicture (PictOpAdd,
					  pPicture,
					  None,
					  pMask,
					  0, 0,
					  0, 0,
					  x - glyph->info.x,
					  y - glyph->info.y,
					  glyph->info.width,
					  glyph->info.height);
		}
		else
		{
		    CompositePicture (op,
				      pSrc,
				      pPicture,
				      pDst,
				      xSrc + (x - glyph->info.x) - xDst,
				      ySrc + (y - glyph->info.y) - yDst,
				      0, 0,
				      x - glyph->info.x,
				      y - glyph->info.y,
				      glyph->info.width,
				      glyph->info.height);
		}
	    }

	    x += glyph->info.xOff;
	    y += glyph->info.yOff;
	}
	list++;
    }
    if (maskFormat)
    {
	x = extents.x1;
	y = extents.y1;
	CompositePicture (op,
			  pSrc,
			  pMask,
			  pDst,
			  xSrc + x - xDst,
			  ySrc + y - yDst,
			  0, 0,
			  x, y,
			  width, height);
	FreePicture ((pointer) pMask, (XID) 0);
	(*pScreen->DestroyPixmap) (pMaskPixmap);
    }
}