gecko/gfx/thebes/gfxPlatform.cpp

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Foundation code.
 *
 * The Initial Developer of the Original Code is Mozilla Foundation.
 * Portions created by the Initial Developer are Copyright (C) 2005
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Vladimir Vukicevic <vladimir@pobox.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "gfxPlatform.h"

#if defined(XP_WIN)
#include "gfxWindowsPlatform.h"
#elif defined(XP_MACOSX)
#include "gfxPlatformMac.h"
#elif defined(MOZ_WIDGET_GTK2)
#include "gfxPlatformGtk.h"
#elif defined(MOZ_WIDGET_QT)
#include "gfxQtPlatform.h"
#elif defined(XP_BEOS)
#include "gfxBeOSPlatform.h"
#elif defined(XP_OS2)
#include "gfxOS2Platform.h"
#elif defined(ANDROID)
#include "gfxAndroidPlatform.h"
#endif

#include "gfxAtoms.h"
#include "gfxPlatformFontList.h"
#include "gfxContext.h"
#include "gfxImageSurface.h"
#include "gfxTextRunCache.h"
#include "gfxTextRunWordCache.h"
#include "gfxUserFontSet.h"

#include "nsUnicodeRange.h"
#include "nsServiceManagerUtils.h"
#include "nsTArray.h"
#include "nsIUGenCategory.h"
#include "nsUnicharUtilCIID.h"
#include "nsILocaleService.h"

#include "nsWeakReference.h"

#include "cairo.h"
#include "qcms.h"

#include "plstr.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsIPrefBranch2.h"
#include "nsIPrefLocalizedString.h"
#include "nsCRT.h"

#include "mozilla/FunctionTimer.h"

gfxPlatform *gPlatform = nsnull;

PRInt32 gfxPlatform::sDPI = -1;

// These two may point to the same profile
static qcms_profile *gCMSOutputProfile = nsnull;
static qcms_profile *gCMSsRGBProfile = nsnull;

static qcms_transform *gCMSRGBTransform = nsnull;
static qcms_transform *gCMSInverseRGBTransform = nsnull;
static qcms_transform *gCMSRGBATransform = nsnull;

static PRBool gCMSInitialized = PR_FALSE;
static eCMSMode gCMSMode = eCMSMode_Off;
static int gCMSIntent = -2;

static const char *CMPrefName = "gfx.color_management.mode";
static const char *CMPrefNameOld = "gfx.color_management.enabled";
static const char *CMIntentPrefName = "gfx.color_management.rendering_intent";
static const char *CMProfilePrefName = "gfx.color_management.display_profile";
static const char *CMForceSRGBPrefName = "gfx.color_management.force_srgb";

static void ShutdownCMS();
static void MigratePrefs();

/* Class to listen for pref changes so that chrome code can dynamically
   force sRGB as an output profile. See Bug #452125. */
class SRGBOverrideObserver : public nsIObserver,
                             public nsSupportsWeakReference
{
public:
    NS_DECL_ISUPPORTS
    NS_DECL_NSIOBSERVER
};

NS_IMPL_ISUPPORTS2(SRGBOverrideObserver, nsIObserver, nsISupportsWeakReference)

NS_IMETHODIMP
SRGBOverrideObserver::Observe(nsISupports *aSubject,
                              const char *aTopic,
                              const PRUnichar *someData)
{
    NS_ASSERTION(NS_strcmp(someData,
                   NS_LITERAL_STRING("gfx.color_mangement.force_srgb").get()),
                 "Restarting CMS on wrong pref!");
    ShutdownCMS();
    return NS_OK;
}

#define GFX_DOWNLOADABLE_FONTS_ENABLED "gfx.downloadable_fonts.enabled"

#define GFX_PREF_HARFBUZZ_LEVEL "gfx.font_rendering.harfbuzz.level"
#define HARFBUZZ_LEVEL_DEFAULT  0

class FontPrefsObserver : public nsIObserver
{
public:
    NS_DECL_ISUPPORTS
    NS_DECL_NSIOBSERVER
};

NS_IMPL_ISUPPORTS1(FontPrefsObserver, nsIObserver)

NS_IMETHODIMP
FontPrefsObserver::Observe(nsISupports *aSubject,
                           const char *aTopic,
                           const PRUnichar *someData)
{
    nsCOMPtr<nsIPrefBranch> branch = do_QueryInterface(aSubject);
    if (!branch || someData == nsnull) {
        NS_ERROR("font pref observer code broken");
        return NS_ERROR_UNEXPECTED;
    }
    
    gfxPlatform::GetPlatform()->FontsPrefsChanged(branch, 
        NS_ConvertUTF16toUTF8(someData).get());

    return NS_OK;
}



// this needs to match the list of pref font.default.xx entries listed in all.js!
// the order *must* match the order in eFontPrefLang
static const char *gPrefLangNames[] = {
    "x-western",
    "x-central-euro",
    "ja",
    "zh-TW",
    "zh-CN",
    "zh-HK",
    "ko",
    "x-cyrillic",
    "x-baltic",
    "el",
    "tr",
    "th",
    "he",
    "ar",
    "x-devanagari",
    "x-tamil",
    "x-armn",
    "x-beng",
    "x-cans",
    "x-ethi",
    "x-geor",
    "x-gujr",
    "x-guru",
    "x-khmr",
    "x-mlym",
    "x-orya",
    "x-telu",
    "x-knda",
    "x-sinh",
    "x-tibt",
    "x-unicode",
    "x-user-def"
};

gfxPlatform::gfxPlatform()
{
    mUseHarfBuzzLevel = UNINITIALIZED_VALUE;
    mAllowDownloadableFonts = UNINITIALIZED_VALUE;
}

gfxPlatform*
gfxPlatform::GetPlatform()
{
    return gPlatform;
}

nsresult
gfxPlatform::Init()
{
    NS_ASSERTION(!gPlatform, "Already started???");

    gfxAtoms::RegisterAtoms();

#if defined(XP_WIN)
    gPlatform = new gfxWindowsPlatform;
#elif defined(XP_MACOSX)
    gPlatform = new gfxPlatformMac;
#elif defined(MOZ_WIDGET_GTK2)
    gPlatform = new gfxPlatformGtk;
#elif defined(MOZ_WIDGET_QT)
    gPlatform = new gfxQtPlatform;
#elif defined(XP_BEOS)
    gPlatform = new gfxBeOSPlatform;
#elif defined(XP_OS2)
    gPlatform = new gfxOS2Platform;
#elif defined(ANDROID)
    gPlatform = new gfxAndroidPlatform;
#endif
    if (!gPlatform)
        return NS_ERROR_OUT_OF_MEMORY;

    nsresult rv;

#if defined(XP_MACOSX) || defined(XP_WIN) // temporary, until this is implemented on others
    rv = gfxPlatformFontList::Init();
    if (NS_FAILED(rv)) {
        NS_ERROR("Could not initialize gfxPlatformFontList");
        Shutdown();
        return rv;
    }
#endif

    rv = gfxFontCache::Init();
    if (NS_FAILED(rv)) {
        NS_ERROR("Could not initialize gfxFontCache");
        Shutdown();
        return rv;
    }

    rv = gfxTextRunWordCache::Init();
    if (NS_FAILED(rv)) {
        NS_ERROR("Could not initialize gfxTextRunWordCache");
        Shutdown();
        return rv;
    }

    rv = gfxTextRunCache::Init();
    if (NS_FAILED(rv)) {
        NS_ERROR("Could not initialize gfxTextRunCache");
        Shutdown();
        return rv;
    }

    /* Pref migration hook. */
    MigratePrefs();

    /* Create and register our CMS Override observer. */
    gPlatform->overrideObserver = new SRGBOverrideObserver();
    FontPrefsObserver *fontPrefObserver = new FontPrefsObserver();

    nsCOMPtr<nsIPrefBranch2> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (prefs) {
        prefs->AddObserver(CMForceSRGBPrefName, gPlatform->overrideObserver, PR_TRUE);
        prefs->AddObserver(GFX_DOWNLOADABLE_FONTS_ENABLED, fontPrefObserver, PR_FALSE);
        prefs->AddObserver("gfx.font_rendering.", fontPrefObserver, PR_FALSE);
    }

    return NS_OK;
}

void
gfxPlatform::Shutdown()
{
    // These may be called before the corresponding subsystems have actually
    // started up. That's OK, they can handle it.
    gfxTextRunCache::Shutdown();
    gfxTextRunWordCache::Shutdown();
    gfxFontCache::Shutdown();
    gfxFontGroup::Shutdown();
#if defined(XP_MACOSX) || defined(XP_WIN) // temporary, until this is implemented on others
    gfxPlatformFontList::Shutdown();
#endif

    // Free the various non-null transforms and loaded profiles
    ShutdownCMS();

    /* Unregister our CMS Override callback. */
    nsCOMPtr<nsIPrefBranch2> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (prefs)
        prefs->RemoveObserver(CMForceSRGBPrefName, gPlatform->overrideObserver);

    delete gPlatform;
    gPlatform = nsnull;
}

gfxPlatform::~gfxPlatform()
{
    // The cairo folks think we should only clean up in debug builds,
    // but we're generally in the habit of trying to shut down as
    // cleanly as possible even in production code, so call this
    // cairo_debug_* function unconditionally.
    //
    // because cairo can assert and thus crash on shutdown, don't do this in release builds
#if MOZ_TREE_CAIRO && (defined(DEBUG) || defined(NS_BUILD_REFCNT_LOGGING) || defined(NS_TRACE_MALLOC))
    cairo_debug_reset_static_data();
#endif

#if 0
    // It would be nice to do this (although it might need to be after
    // the cairo shutdown that happens in ~gfxPlatform).  It even looks
    // idempotent.  But it has fatal assertions that fire if stuff is
    // leaked, and we hit them.
    FcFini();
#endif
}

already_AddRefed<gfxASurface>
gfxPlatform::OptimizeImage(gfxImageSurface *aSurface,
                           gfxASurface::gfxImageFormat format)
{
    const gfxIntSize& surfaceSize = aSurface->GetSize();

#ifdef XP_WIN
    if (gfxWindowsPlatform::GetPlatform()->GetRenderMode() == 
        gfxWindowsPlatform::RENDER_DIRECT2D) {
        return nsnull;
    }
#endif
    nsRefPtr<gfxASurface> optSurface = CreateOffscreenSurface(surfaceSize, format);
    if (!optSurface || optSurface->CairoStatus() != 0)
        return nsnull;

    gfxContext tmpCtx(optSurface);
    tmpCtx.SetOperator(gfxContext::OPERATOR_SOURCE);
    tmpCtx.SetSource(aSurface);
    tmpCtx.Paint();

    gfxASurface *ret = optSurface;
    NS_ADDREF(ret);
    return ret;
}

nsresult
gfxPlatform::GetFontList(nsIAtom *aLangGroup,
                         const nsACString& aGenericFamily,
                         nsTArray<nsString>& aListOfFonts)
{
    return NS_ERROR_NOT_IMPLEMENTED;
}

nsresult
gfxPlatform::UpdateFontList()
{
    return NS_ERROR_NOT_IMPLEMENTED;
}

PRBool 
gfxPlatform::GetBoolPref(const char *aPref, PRBool aDefault)
{
    nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (prefs) {
        PRBool allow;
        nsresult rv = prefs->GetBoolPref(aPref, &allow);
        if (NS_SUCCEEDED(rv))
            return allow;
    }

    return aDefault;
}

PRBool
gfxPlatform::DownloadableFontsEnabled()
{
    if (mAllowDownloadableFonts == UNINITIALIZED_VALUE) {
        mAllowDownloadableFonts = GetBoolPref(GFX_DOWNLOADABLE_FONTS_ENABLED, PR_FALSE);
    }

    return mAllowDownloadableFonts;
}

PRInt8
gfxPlatform::UseHarfBuzzLevel()
{
    if (mUseHarfBuzzLevel == UNINITIALIZED_VALUE) {
        mUseHarfBuzzLevel = HARFBUZZ_LEVEL_DEFAULT;
        nsCOMPtr<nsIPrefBranch2> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
        if (prefs) {
            PRInt32 level;
            nsresult rv = prefs->GetIntPref(GFX_PREF_HARFBUZZ_LEVEL, &level);
            if (NS_SUCCEEDED(rv)) {
                mUseHarfBuzzLevel = level;
            }
        }
    }

    return mUseHarfBuzzLevel;
}

gfxFontEntry*
gfxPlatform::MakePlatformFont(const gfxProxyFontEntry *aProxyEntry,
                              const PRUint8 *aFontData,
                              PRUint32 aLength)
{
    // Default implementation does not handle activating downloaded fonts;
    // just free the data and return.
    // Platforms that support @font-face must override this,
    // using the data to instantiate the font, and taking responsibility
    // for freeing it when no longer required.
    if (aFontData) {
        NS_Free((void*)aFontData);
    }
    return nsnull;
}

static void
AppendGenericFontFromPref(nsString& aFonts, nsIAtom *aLangGroup, const char *aGenericName)
{
    nsresult rv;

    nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
    if (!prefs)
        return;

    nsCAutoString prefName, langGroupString;
    nsXPIDLCString nameValue, nameListValue;

    aLangGroup->ToUTF8String(langGroupString);

    nsCAutoString genericDotLang;
    if (aGenericName) {
        genericDotLang.Assign(aGenericName);
    } else {
        prefName.AssignLiteral("font.default.");
        prefName.Append(langGroupString);
        prefs->GetCharPref(prefName.get(), getter_Copies(genericDotLang));
    }

    genericDotLang.AppendLiteral(".");
    genericDotLang.Append(langGroupString);

    // fetch font.name.xxx value                   
    prefName.AssignLiteral("font.name.");
    prefName.Append(genericDotLang);
    rv = prefs->GetCharPref(prefName.get(), getter_Copies(nameValue));
    if (NS_SUCCEEDED(rv)) {
        if (!aFonts.IsEmpty())
            aFonts.AppendLiteral(", ");
        aFonts.Append(NS_ConvertUTF8toUTF16(nameValue));
    }

    // fetch font.name-list.xxx value                   
    prefName.AssignLiteral("font.name-list.");
    prefName.Append(genericDotLang);
    rv = prefs->GetCharPref(prefName.get(), getter_Copies(nameListValue));
    if (NS_SUCCEEDED(rv) && !nameListValue.Equals(nameValue)) {
        if (!aFonts.IsEmpty())
            aFonts.AppendLiteral(", ");
        aFonts.Append(NS_ConvertUTF8toUTF16(nameListValue));
    }
}

void
gfxPlatform::GetPrefFonts(nsIAtom *aLanguage, nsString& aFonts, PRBool aAppendUnicode)
{
    aFonts.Truncate();

    AppendGenericFontFromPref(aFonts, aLanguage, nsnull);
    if (aAppendUnicode)
        AppendGenericFontFromPref(aFonts, gfxAtoms::x_unicode, nsnull);
}

PRBool gfxPlatform::ForEachPrefFont(eFontPrefLang aLangArray[], PRUint32 aLangArrayLen, PrefFontCallback aCallback,
                                    void *aClosure)
{
    nsresult rv;

    nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
    if (!prefs)
        return PR_FALSE;

    PRUint32    i;
    
    for (i = 0; i < aLangArrayLen; i++) {
        eFontPrefLang prefLang = aLangArray[i];
        const char *langGroup = GetPrefLangName(prefLang);
        
        nsCAutoString prefName;
        nsXPIDLCString nameValue, nameListValue;
    
        nsCAutoString genericDotLang;
        prefName.AssignLiteral("font.default.");
        prefName.Append(langGroup);
        prefs->GetCharPref(prefName.get(), getter_Copies(genericDotLang));
    
        genericDotLang.AppendLiteral(".");
        genericDotLang.Append(langGroup);
    
        // fetch font.name.xxx value                   
        prefName.AssignLiteral("font.name.");
        prefName.Append(genericDotLang);
        rv = prefs->GetCharPref(prefName.get(), getter_Copies(nameValue));
        if (NS_SUCCEEDED(rv)) {
            if (!aCallback(prefLang, NS_ConvertUTF8toUTF16(nameValue), aClosure))
                return PR_FALSE;
        }
    
        // fetch font.name-list.xxx value                   
        prefName.AssignLiteral("font.name-list.");
        prefName.Append(genericDotLang);
        rv = prefs->GetCharPref(prefName.get(), getter_Copies(nameListValue));
        if (NS_SUCCEEDED(rv) && !nameListValue.Equals(nameValue)) {
            const char kComma = ',';
            const char *p, *p_end;
            nsCAutoString list(nameListValue);
            list.BeginReading(p);
            list.EndReading(p_end);
            while (p < p_end) {
                while (nsCRT::IsAsciiSpace(*p)) {
                    if (++p == p_end)
                        break;
                }
                if (p == p_end)
                    break;
                const char *start = p;
                while (++p != p_end && *p != kComma)
                    /* nothing */ ;
                nsCAutoString fontName(Substring(start, p));
                fontName.CompressWhitespace(PR_FALSE, PR_TRUE);
                if (!aCallback(prefLang, NS_ConvertUTF8toUTF16(fontName), aClosure))
                    return PR_FALSE;
                p++;
            }
        }
    }

    return PR_TRUE;
}

eFontPrefLang
gfxPlatform::GetFontPrefLangFor(const char* aLang)
{
    if (!aLang || !aLang[0])
        return eFontPrefLang_Others;
    for (PRUint32 i = 0; i < PRUint32(eFontPrefLang_LangCount); ++i) {
        if (!PL_strcasecmp(gPrefLangNames[i], aLang))
            return eFontPrefLang(i);
    }
    return eFontPrefLang_Others;
}

eFontPrefLang
gfxPlatform::GetFontPrefLangFor(nsIAtom *aLang)
{
    if (!aLang)
        return eFontPrefLang_Others;
    nsCAutoString lang;
    aLang->ToUTF8String(lang);
    return GetFontPrefLangFor(lang.get());
}

const char*
gfxPlatform::GetPrefLangName(eFontPrefLang aLang)
{
    if (PRUint32(aLang) < PRUint32(eFontPrefLang_AllCount))
        return gPrefLangNames[PRUint32(aLang)];
    return nsnull;
}

eFontPrefLang
gfxPlatform::GetFontPrefLangFor(PRUint8 aUnicodeRange)
{
    switch (aUnicodeRange) {
        case kRangeSetLatin:   return eFontPrefLang_Western;
        case kRangeCyrillic:   return eFontPrefLang_Cyrillic;
        case kRangeGreek:      return eFontPrefLang_Greek;
        case kRangeTurkish:    return eFontPrefLang_Turkish;
        case kRangeHebrew:     return eFontPrefLang_Hebrew;
        case kRangeArabic:     return eFontPrefLang_Arabic;
        case kRangeBaltic:     return eFontPrefLang_Baltic;
        case kRangeThai:       return eFontPrefLang_Thai;
        case kRangeKorean:     return eFontPrefLang_Korean;
        case kRangeJapanese:   return eFontPrefLang_Japanese;
        case kRangeSChinese:   return eFontPrefLang_ChineseCN;
        case kRangeTChinese:   return eFontPrefLang_ChineseTW;
        case kRangeDevanagari: return eFontPrefLang_Devanagari;
        case kRangeTamil:      return eFontPrefLang_Tamil;
        case kRangeArmenian:   return eFontPrefLang_Armenian;
        case kRangeBengali:    return eFontPrefLang_Bengali;
        case kRangeCanadian:   return eFontPrefLang_Canadian;
        case kRangeEthiopic:   return eFontPrefLang_Ethiopic;
        case kRangeGeorgian:   return eFontPrefLang_Georgian;
        case kRangeGujarati:   return eFontPrefLang_Gujarati;
        case kRangeGurmukhi:   return eFontPrefLang_Gurmukhi;
        case kRangeKhmer:      return eFontPrefLang_Khmer;
        case kRangeMalayalam:  return eFontPrefLang_Malayalam;
        case kRangeSetCJK:     return eFontPrefLang_CJKSet;
        default:               return eFontPrefLang_Others;
    }
}

PRBool 
gfxPlatform::IsLangCJK(eFontPrefLang aLang)
{
    switch (aLang) {
        case eFontPrefLang_Japanese:
        case eFontPrefLang_ChineseTW:
        case eFontPrefLang_ChineseCN:
        case eFontPrefLang_ChineseHK:
        case eFontPrefLang_Korean:
        case eFontPrefLang_CJKSet:
            return PR_TRUE;
        default:
            return PR_FALSE;
    }
}

void 
gfxPlatform::GetLangPrefs(eFontPrefLang aPrefLangs[], PRUint32 &aLen, eFontPrefLang aCharLang, eFontPrefLang aPageLang)
{
    if (IsLangCJK(aCharLang)) {
        AppendCJKPrefLangs(aPrefLangs, aLen, aCharLang, aPageLang);
    } else {
        AppendPrefLang(aPrefLangs, aLen, aCharLang);
    }

    AppendPrefLang(aPrefLangs, aLen, eFontPrefLang_Others);
}

void
gfxPlatform::AppendCJKPrefLangs(eFontPrefLang aPrefLangs[], PRUint32 &aLen, eFontPrefLang aCharLang, eFontPrefLang aPageLang)
{
    nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));

    // prefer the lang specified by the page *if* CJK
    if (IsLangCJK(aPageLang)) {
        AppendPrefLang(aPrefLangs, aLen, aPageLang);
    }
    
    // if not set up, set up the default CJK order, based on accept lang settings and locale
    if (mCJKPrefLangs.Length() == 0) {
    
        // temp array
        eFontPrefLang tempPrefLangs[kMaxLenPrefLangList];
        PRUint32 tempLen = 0;
        
        // Add the CJK pref fonts from accept languages, the order should be same order
        nsCAutoString list;
        if (prefs) {
            nsCOMPtr<nsIPrefLocalizedString> prefString;
            nsresult rv =
                prefs->GetComplexValue("intl.accept_languages",
                                       NS_GET_IID(nsIPrefLocalizedString),
                                       getter_AddRefs(prefString));
            if (NS_SUCCEEDED(rv) && prefString) {
                nsAutoString temp;
                prefString->ToString(getter_Copies(temp));
                LossyCopyUTF16toASCII(temp, list);
            }
        }
        
        if (!list.IsEmpty()) {
            const char kComma = ',';
            const char *p, *p_end;
            list.BeginReading(p);
            list.EndReading(p_end);
            while (p < p_end) {
                while (nsCRT::IsAsciiSpace(*p)) {
                    if (++p == p_end)
                        break;
                }
                if (p == p_end)
                    break;
                const char *start = p;
                while (++p != p_end && *p != kComma)
                    /* nothing */ ;
                nsCAutoString lang(Substring(start, p));
                lang.CompressWhitespace(PR_FALSE, PR_TRUE);
                eFontPrefLang fpl = gfxPlatform::GetFontPrefLangFor(lang.get());
                switch (fpl) {
                    case eFontPrefLang_Japanese:
                    case eFontPrefLang_Korean:
                    case eFontPrefLang_ChineseCN:
                    case eFontPrefLang_ChineseHK:
                    case eFontPrefLang_ChineseTW:
                        AppendPrefLang(tempPrefLangs, tempLen, fpl);
                        break;
                    default:
                        break;
                }
                p++;
            }
        }

        do { // to allow 'break' to abort this block if a call fails
            nsresult rv;
            nsCOMPtr<nsILocaleService> ls =
                do_GetService(NS_LOCALESERVICE_CONTRACTID, &rv);
            if (NS_FAILED(rv))
                break;

            nsCOMPtr<nsILocale> appLocale;
            rv = ls->GetApplicationLocale(getter_AddRefs(appLocale));
            if (NS_FAILED(rv))
                break;

            nsString localeStr;
            rv = appLocale->
                GetCategory(NS_LITERAL_STRING(NSILOCALE_MESSAGE), localeStr);
            if (NS_FAILED(rv))
                break;

            const nsAString& lang = Substring(localeStr, 0, 2);
            if (lang.EqualsLiteral("ja")) {
                AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_Japanese);
            } else if (lang.EqualsLiteral("zh")) {
                const nsAString& region = Substring(localeStr, 3, 2);
                if (region.EqualsLiteral("CN")) {
                    AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseCN);
                } else if (region.EqualsLiteral("TW")) {
                    AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseTW);
                } else if (region.EqualsLiteral("HK")) {
                    AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseHK);
                }
            } else if (lang.EqualsLiteral("ko")) {
                AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_Korean);
            }
        } while (0);

        // last resort... (the order is same as old gfx.)
        AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_Japanese);
        AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_Korean);
        AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseCN);
        AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseHK);
        AppendPrefLang(tempPrefLangs, tempLen, eFontPrefLang_ChineseTW);
        
        // copy into the cached array
        PRUint32 j;
        for (j = 0; j < tempLen; j++) {
            mCJKPrefLangs.AppendElement(tempPrefLangs[j]);
        }
    }
    
    // append in cached CJK langs
    PRUint32  i, numCJKlangs = mCJKPrefLangs.Length();
    
    for (i = 0; i < numCJKlangs; i++) {
        AppendPrefLang(aPrefLangs, aLen, (eFontPrefLang) (mCJKPrefLangs[i]));
    }
        
}

void 
gfxPlatform::AppendPrefLang(eFontPrefLang aPrefLangs[], PRUint32& aLen, eFontPrefLang aAddLang)
{
    if (aLen >= kMaxLenPrefLangList) return;
    
    // make sure
    PRUint32  i = 0;
    while (i < aLen && aPrefLangs[i] != aAddLang) {
        i++;
    }
    
    if (i == aLen) {
        aPrefLangs[aLen] = aAddLang;
        aLen++;
    }
}

eCMSMode
gfxPlatform::GetCMSMode()
{
    if (gCMSInitialized == PR_FALSE) {
        gCMSInitialized = PR_TRUE;
        nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
        if (prefs) {
            PRInt32 mode;
            nsresult rv =
                prefs->GetIntPref(CMPrefName, &mode);
            if (NS_SUCCEEDED(rv) && (mode >= 0) && (mode < eCMSMode_AllCount)) {
                gCMSMode = static_cast<eCMSMode>(mode);
            }
        }
    }
    return gCMSMode;
}

/* Chris Murphy (CM consultant) suggests this as a default in the event that we
cannot reproduce relative + Black Point Compensation.  BPC brings an
unacceptable performance overhead, so we go with perceptual. */
#define INTENT_DEFAULT QCMS_INTENT_PERCEPTUAL
#define INTENT_MIN 0
#define INTENT_MAX 3

PRBool
gfxPlatform::GetRenderingIntent()
{
    if (gCMSIntent == -2) {

        /* Try to query the pref system for a rendering intent. */
        nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
        if (prefs) {
            PRInt32 pIntent;
            nsresult rv = prefs->GetIntPref(CMIntentPrefName, &pIntent);
            if (NS_SUCCEEDED(rv)) {
              
                /* If the pref is within range, use it as an override. */
                if ((pIntent >= INTENT_MIN) && (pIntent <= INTENT_MAX))
                    gCMSIntent = pIntent;

                /* If the pref is out of range, use embedded profile. */
                else
                    gCMSIntent = -1;
            }
        }

        /* If we didn't get a valid intent from prefs, use the default. */
        if (gCMSIntent == -2) 
            gCMSIntent = INTENT_DEFAULT;
    }
    return gCMSIntent;
}

void 
gfxPlatform::TransformPixel(const gfxRGBA& in, gfxRGBA& out, qcms_transform *transform)
{

    if (transform) {
        /* we want the bytes in RGB order */
#ifdef IS_LITTLE_ENDIAN
        /* ABGR puts the bytes in |RGBA| order on little endian */
        PRUint32 packed = in.Packed(gfxRGBA::PACKED_ABGR);
        qcms_transform_data(transform,
                       (PRUint8 *)&packed, (PRUint8 *)&packed,
                       1);
        out.~gfxRGBA();
        new (&out) gfxRGBA(packed, gfxRGBA::PACKED_ABGR);
#else
        /* ARGB puts the bytes in |ARGB| order on big endian */
        PRUint32 packed = in.Packed(gfxRGBA::PACKED_ARGB);
        /* add one to move past the alpha byte */
        qcms_transform_data(transform,
                       (PRUint8 *)&packed + 1, (PRUint8 *)&packed + 1,
                       1);
        out.~gfxRGBA();
        new (&out) gfxRGBA(packed, gfxRGBA::PACKED_ARGB);
#endif
    }

    else if (&out != &in)
        out = in;
}

qcms_profile *
gfxPlatform::GetPlatformCMSOutputProfile()
{
    return nsnull;
}

qcms_profile *
gfxPlatform::GetCMSOutputProfile()
{
    if (!gCMSOutputProfile) {
        NS_TIME_FUNCTION;

        nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
        if (prefs) {

            nsresult rv;

            /* Determine if we're using the internal override to force sRGB as
               an output profile for reftests. See Bug 452125. */
            PRBool hasSRGBOverride, doSRGBOverride;
            rv = prefs->PrefHasUserValue(CMForceSRGBPrefName, &hasSRGBOverride);
            if (NS_SUCCEEDED(rv) && hasSRGBOverride) {
                rv = prefs->GetBoolPref(CMForceSRGBPrefName, &doSRGBOverride);
                if (NS_SUCCEEDED(rv) && doSRGBOverride)
                    gCMSOutputProfile = GetCMSsRGBProfile();
            }

            if (!gCMSOutputProfile) {

                nsXPIDLCString fname;
                rv = prefs->GetCharPref(CMProfilePrefName,
                                        getter_Copies(fname));
                if (NS_SUCCEEDED(rv) && !fname.IsEmpty()) {
                    gCMSOutputProfile = qcms_profile_from_path(fname);
                }
            }
        }

        if (!gCMSOutputProfile) {
            gCMSOutputProfile =
                gfxPlatform::GetPlatform()->GetPlatformCMSOutputProfile();
        }

        /* Determine if the profile looks bogus. If so, close the profile
         * and use sRGB instead. See bug 460629, */
        if (gCMSOutputProfile && qcms_profile_is_bogus(gCMSOutputProfile)) {
            NS_ASSERTION(gCMSOutputProfile != GetCMSsRGBProfile(),
                         "Builtin sRGB profile tagged as bogus!!!");
            qcms_profile_release(gCMSOutputProfile);
            gCMSOutputProfile = nsnull;
        }

        if (!gCMSOutputProfile) {
            gCMSOutputProfile = GetCMSsRGBProfile();
        }
        /* Precache the LUT16 Interpolations for the output profile. See 
           bug 444661 for details. */
        qcms_profile_precache_output_transform(gCMSOutputProfile);
    }

    return gCMSOutputProfile;
}

qcms_profile *
gfxPlatform::GetCMSsRGBProfile()
{
    if (!gCMSsRGBProfile) {

        /* Create the profile using qcms. */
        gCMSsRGBProfile = qcms_profile_sRGB();
    }
    return gCMSsRGBProfile;
}

qcms_transform *
gfxPlatform::GetCMSRGBTransform()
{
    if (!gCMSRGBTransform) {
        qcms_profile *inProfile, *outProfile;
        outProfile = GetCMSOutputProfile();
        inProfile = GetCMSsRGBProfile();

        if (!inProfile || !outProfile)
            return nsnull;

        gCMSRGBTransform = qcms_transform_create(inProfile, QCMS_DATA_RGB_8,
                                              outProfile, QCMS_DATA_RGB_8,
                                             QCMS_INTENT_PERCEPTUAL);
    }

    return gCMSRGBTransform;
}

qcms_transform *
gfxPlatform::GetCMSInverseRGBTransform()
{
    if (!gCMSInverseRGBTransform) {
        qcms_profile *inProfile, *outProfile;
        inProfile = GetCMSOutputProfile();
        outProfile = GetCMSsRGBProfile();

        if (!inProfile || !outProfile)
            return nsnull;

        gCMSInverseRGBTransform = qcms_transform_create(inProfile, QCMS_DATA_RGB_8,
                                                     outProfile, QCMS_DATA_RGB_8,
                                                     QCMS_INTENT_PERCEPTUAL);
    }

    return gCMSInverseRGBTransform;
}

qcms_transform *
gfxPlatform::GetCMSRGBATransform()
{
    if (!gCMSRGBATransform) {
        qcms_profile *inProfile, *outProfile;
        outProfile = GetCMSOutputProfile();
        inProfile = GetCMSsRGBProfile();

        if (!inProfile || !outProfile)
            return nsnull;

        gCMSRGBATransform = qcms_transform_create(inProfile, QCMS_DATA_RGBA_8,
                                               outProfile, QCMS_DATA_RGBA_8,
                                               QCMS_INTENT_PERCEPTUAL);
    }

    return gCMSRGBATransform;
}

/* Shuts down various transforms and profiles for CMS. */
static void ShutdownCMS()
{

    if (gCMSRGBTransform) {
        qcms_transform_release(gCMSRGBTransform);
        gCMSRGBTransform = nsnull;
    }
    if (gCMSInverseRGBTransform) {
        qcms_transform_release(gCMSInverseRGBTransform);
        gCMSInverseRGBTransform = nsnull;
    }
    if (gCMSRGBATransform) {
        qcms_transform_release(gCMSRGBATransform);
        gCMSRGBATransform = nsnull;
    }
    if (gCMSOutputProfile) {
        qcms_profile_release(gCMSOutputProfile);

        // handle the aliased case
        if (gCMSsRGBProfile == gCMSOutputProfile)
            gCMSsRGBProfile = nsnull;
        gCMSOutputProfile = nsnull;
    }
    if (gCMSsRGBProfile) {
        qcms_profile_release(gCMSsRGBProfile);
        gCMSsRGBProfile = nsnull;
    }

    // Reset the state variables
    gCMSIntent = -2;
    gCMSMode = eCMSMode_Off;
    gCMSInitialized = PR_FALSE;
}

static void MigratePrefs()
{

    /* Load the pref service. If we don't get it die quietly since this isn't
       critical code. */
    nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (!prefs)
        return;

    /* Migrate from the boolean color_management.enabled pref - we now use
       color_management.mode. */
    PRBool hasOldCMPref;
    nsresult rv =
        prefs->PrefHasUserValue(CMPrefNameOld, &hasOldCMPref);
    if (NS_SUCCEEDED(rv) && (hasOldCMPref == PR_TRUE)) {
        PRBool CMWasEnabled;
        rv = prefs->GetBoolPref(CMPrefNameOld, &CMWasEnabled);
        if (NS_SUCCEEDED(rv) && (CMWasEnabled == PR_TRUE))
            prefs->SetIntPref(CMPrefName, eCMSMode_All);
        prefs->ClearUserPref(CMPrefNameOld);
    }

}

void
gfxPlatform::InitDisplayCaps()
{
    // Fall back to something sane
    gfxPlatform::sDPI = 96;
}

// default SetupClusterBoundaries, based on Unicode properties;
// platform subclasses may override if they wish
static nsIUGenCategory* gGenCategory = nsnull;

static nsIUGenCategory*
GetGenCategory()
{
    if (!gGenCategory) {
        nsresult rv = CallGetService(NS_UNICHARCATEGORY_CONTRACTID, &gGenCategory);
        if (NS_FAILED(rv)) {
            NS_ERROR("Failed to get the Unicode character category service!");
            gGenCategory = nsnull;
        }
    }
    return gGenCategory;
}

void
gfxPlatform::SetupClusterBoundaries(gfxTextRun *aTextRun, const PRUnichar *aString)
{
    if (aTextRun->GetFlags() & gfxTextRunFactory::TEXT_IS_8BIT) {
        // 8-bit text doesn't have clusters.
        // XXX is this true in all languages???
        // behdad: don't think so.  Czech for example IIRC has a
        // 'ch' grapheme.
        return;
    }

    nsIUGenCategory* gc = GetGenCategory();
    if (!gc) {
        NS_WARNING("No Unicode category service: cannot determine clusters");
        return;
    }

    PRUint32 i, length = aTextRun->GetLength();
    for (i = 0; i < length; ++i) {
        PRBool surrogatePair = PR_FALSE;
        PRUint32 ch = aString[i];
        if (NS_IS_HIGH_SURROGATE(ch) &&
            i < length - 1 && NS_IS_LOW_SURROGATE(aString[i+1])) {
            ch = SURROGATE_TO_UCS4(ch, aString[i+1]);
            surrogatePair = PR_TRUE;
        }
        if (i > 0 && gc->Get(ch) == nsIUGenCategory::kMark) {
            gfxTextRun::CompressedGlyph g;
            aTextRun->SetGlyphs(i, g.SetComplex(PR_FALSE, PR_TRUE, 0), nsnull);
        }
        if (surrogatePair) {
            ++i;
            gfxTextRun::CompressedGlyph g;
            aTextRun->SetGlyphs(i, g.SetComplex(PR_FALSE, PR_TRUE, 0), nsnull);
        }
    }
}

void
gfxPlatform::FontsPrefsChanged(nsIPrefBranch *aPrefBranch, const char *aPref)
{
    NS_ASSERTION(aPref != nsnull, "null preference");
    if (!strcmp(GFX_DOWNLOADABLE_FONTS_ENABLED, aPref)) {
        mAllowDownloadableFonts = UNINITIALIZED_VALUE;
    } else if (!strcmp(GFX_PREF_HARFBUZZ_LEVEL, aPref)) {
        mUseHarfBuzzLevel = UNINITIALIZED_VALUE;
        gfxTextRunWordCache::Flush();
        gfxFontCache::GetCache()->AgeAllGenerations();
    }
}