gecko-dev/gfx/thebes/gfxFontconfigUtils.h
2012-05-21 12:12:37 +01:00

321 lines
11 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef GFX_FONTCONFIG_UTILS_H
#define GFX_FONTCONFIG_UTILS_H
#include "gfxPlatform.h"
#include "nsAutoRef.h"
#include "nsTArray.h"
#include "nsTHashtable.h"
#include "nsISupportsImpl.h"
#include <fontconfig/fontconfig.h>
template <>
class nsAutoRefTraits<FcPattern> : public nsPointerRefTraits<FcPattern>
{
public:
static void Release(FcPattern *ptr) { FcPatternDestroy(ptr); }
static void AddRef(FcPattern *ptr) { FcPatternReference(ptr); }
};
template <>
class nsAutoRefTraits<FcFontSet> : public nsPointerRefTraits<FcFontSet>
{
public:
static void Release(FcFontSet *ptr) { FcFontSetDestroy(ptr); }
};
template <>
class nsAutoRefTraits<FcCharSet> : public nsPointerRefTraits<FcCharSet>
{
public:
static void Release(FcCharSet *ptr) { FcCharSetDestroy(ptr); }
};
class gfxIgnoreCaseCStringComparator
{
public:
bool Equals(const nsACString& a, const nsACString& b) const
{
return nsCString(a).Equals(b, nsCaseInsensitiveCStringComparator());
}
bool LessThan(const nsACString& a, const nsACString& b) const
{
return a < b;
}
};
class gfxFontNameList : public nsTArray<nsString>
{
public:
NS_INLINE_DECL_REFCOUNTING(gfxFontNameList)
bool Exists(nsAString& aName);
};
class gfxFontconfigUtils {
public:
gfxFontconfigUtils();
static gfxFontconfigUtils* GetFontconfigUtils() {
if (!sUtils)
sUtils = new gfxFontconfigUtils();
return sUtils;
}
static void Shutdown();
nsresult GetFontList(nsIAtom *aLangGroup,
const nsACString& aGenericFamily,
nsTArray<nsString>& aListOfFonts);
nsresult UpdateFontList();
nsresult ResolveFontName(const nsAString& aFontName,
gfxPlatform::FontResolverCallback aCallback,
void *aClosure, bool& aAborted);
nsresult GetStandardFamilyName(const nsAString& aFontName, nsAString& aFamilyName);
const nsTArray< nsCountedRef<FcPattern> >&
GetFontsForFamily(const FcChar8 *aFamilyName);
const nsTArray< nsCountedRef<FcPattern> >&
GetFontsForFullname(const FcChar8 *aFullname);
// Returns the best support that any font offers for |aLang|.
FcLangResult GetBestLangSupport(const FcChar8 *aLang);
// Returns the fonts offering this best level of support.
const nsTArray< nsCountedRef<FcPattern> >&
GetFontsForLang(const FcChar8 *aLang);
// Retuns the language support for a fontconfig font pattern
static FcLangResult GetLangSupport(FcPattern *aFont, const FcChar8 *aLang);
// Conversions between FcChar8*, which is unsigned char*,
// and (signed) char*, that check the type of the argument.
static const FcChar8 *ToFcChar8(const char *aCharPtr)
{
return reinterpret_cast<const FcChar8*>(aCharPtr);
}
static const FcChar8 *ToFcChar8(const nsCString& aCString)
{
return ToFcChar8(aCString.get());
}
static const char *ToCString(const FcChar8 *aChar8Ptr)
{
return reinterpret_cast<const char*>(aChar8Ptr);
}
static PRUint8 FcSlantToThebesStyle(int aFcSlant);
static PRUint8 GetThebesStyle(FcPattern *aPattern); // slant
static PRUint16 GetThebesWeight(FcPattern *aPattern);
static PRInt16 GetThebesStretch(FcPattern *aPattern);
static int GetFcSlant(const gfxFontStyle& aFontStyle);
// Returns a precise FC_WEIGHT from |aBaseWeight|,
// which is a CSS absolute weight / 100.
static int FcWeightForBaseWeight(PRInt8 aBaseWeight);
static int FcWidthForThebesStretch(PRInt16 aStretch);
static bool GetFullnameFromFamilyAndStyle(FcPattern *aFont,
nsACString *aFullname);
// This doesn't consider which faces exist, and so initializes the pattern
// using a guessed weight, and doesn't consider sizeAdjust.
static nsReturnRef<FcPattern>
NewPattern(const nsTArray<nsString>& aFamilies,
const gfxFontStyle& aFontStyle, const char *aLang);
/**
* @param aLangGroup [in] a Mozilla langGroup.
* @param aFcLang [out] returns a language suitable for fontconfig
* matching |aLangGroup| or an empty string if no match is found.
*/
static void GetSampleLangForGroup(nsIAtom *aLangGroup,
nsACString *aFcLang);
protected:
// Base class for hash table entries with case-insensitive FcChar8
// string keys.
class FcStrEntryBase : public PLDHashEntryHdr {
public:
typedef const FcChar8 *KeyType;
typedef const FcChar8 *KeyTypePointer;
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
// Case-insensitive hash.
//
// fontconfig always ignores case of ASCII characters in family
// names and languages, but treatment of whitespace in families is
// not consistent. FcFontSort and FcFontMatch ignore whitespace
// except for whitespace in the first character, while FcFontList
// and config subsitution tests require whitespace to match
// exactly. CSS 2.1 implies that whitespace is important in the
// font-family property. FcStrCmpIgnoreCase considers whitespace
// important.
static PLDHashNumber HashKey(const FcChar8 *aKey) {
PRUint32 hash = 0;
for (const FcChar8 *c = aKey; *c != '\0'; ++c) {
hash = PR_ROTATE_LEFT32(hash, 3) ^ FcToLower(*c);
}
return hash;
}
enum { ALLOW_MEMMOVE = true };
};
public:
// Hash entry with a dependent const FcChar8* pointer to an external
// string for a key (and no data). The user must ensure that the string
// associated with the pointer is not destroyed. This entry type is
// useful for family name keys as the family name string is held in the
// font pattern.
class DepFcStrEntry : public FcStrEntryBase {
public:
// When constructing a new entry in the hashtable, the key is left
// NULL. The caller of PutEntry() must fill in mKey when NULL. This
// provides a mechanism for the caller of PutEntry() to determine
// whether the entry has been initialized.
DepFcStrEntry(KeyTypePointer aName)
: mKey(NULL) { }
DepFcStrEntry(const DepFcStrEntry& toCopy)
: mKey(toCopy.mKey) { }
bool KeyEquals(KeyTypePointer aKey) const {
return FcStrCmpIgnoreCase(aKey, mKey) == 0;
}
const FcChar8 *mKey;
};
// Hash entry that uses a copy of an FcChar8 string to store the key.
// This entry type is useful for language keys, as languages are usually
// not stored as strings in font patterns.
class CopiedFcStrEntry : public FcStrEntryBase {
public:
// When constructing a new entry in the hashtable, the key is void.
// The caller of PutEntry() must call InitKey() when IsKeyInitialized()
// returns false. This provides a mechanism for the caller of
// PutEntry() to determine whether the entry has been initialized.
CopiedFcStrEntry(KeyTypePointer aName) {
mKey.SetIsVoid(true);
}
CopiedFcStrEntry(const CopiedFcStrEntry& toCopy)
: mKey(toCopy.mKey) { }
bool KeyEquals(KeyTypePointer aKey) const {
return FcStrCmpIgnoreCase(aKey, ToFcChar8(mKey)) == 0;
}
bool IsKeyInitialized() { return !mKey.IsVoid(); }
void InitKey(const FcChar8* aKey) { mKey.Assign(ToCString(aKey)); }
private:
nsCString mKey;
};
protected:
class FontsByFcStrEntry : public DepFcStrEntry {
public:
FontsByFcStrEntry(KeyTypePointer aName)
: DepFcStrEntry(aName) { }
FontsByFcStrEntry(const FontsByFcStrEntry& toCopy)
: DepFcStrEntry(toCopy), mFonts(toCopy.mFonts) { }
bool AddFont(FcPattern *aFont) {
return mFonts.AppendElement(aFont) != nsnull;
}
const nsTArray< nsCountedRef<FcPattern> >& GetFonts() {
return mFonts;
}
private:
nsTArray< nsCountedRef<FcPattern> > mFonts;
};
// FontsByFullnameEntry is similar to FontsByFcStrEntry (used for
// mFontsByFamily) except for two differences:
//
// * The font does not always contain a single string for the fullname, so
// the key is sometimes a combination of family and style.
//
// * There is usually only one font.
class FontsByFullnameEntry : public DepFcStrEntry {
public:
// When constructing a new entry in the hashtable, the key is left
// NULL. The caller of PutEntry() is must fill in mKey when adding
// the first font if the key is not derived from the family and style.
// If the key is derived from family and style, a font must be added.
FontsByFullnameEntry(KeyTypePointer aName)
: DepFcStrEntry(aName) { }
FontsByFullnameEntry(const FontsByFullnameEntry& toCopy)
: DepFcStrEntry(toCopy), mFonts(toCopy.mFonts) { }
bool KeyEquals(KeyTypePointer aKey) const;
bool AddFont(FcPattern *aFont) {
return mFonts.AppendElement(aFont) != nsnull;
}
const nsTArray< nsCountedRef<FcPattern> >& GetFonts() {
return mFonts;
}
// Don't memmove the nsAutoTArray.
enum { ALLOW_MEMMOVE = false };
private:
// There is usually only one font, but sometimes more.
nsAutoTArray<nsCountedRef<FcPattern>,1> mFonts;
};
class LangSupportEntry : public CopiedFcStrEntry {
public:
LangSupportEntry(KeyTypePointer aName)
: CopiedFcStrEntry(aName) { }
LangSupportEntry(const LangSupportEntry& toCopy)
: CopiedFcStrEntry(toCopy), mSupport(toCopy.mSupport) { }
FcLangResult mSupport;
nsTArray< nsCountedRef<FcPattern> > mFonts;
};
static gfxFontconfigUtils* sUtils;
bool IsExistingFamily(const nsCString& aFamilyName);
nsresult GetFontListInternal(nsTArray<nsCString>& aListOfFonts,
nsIAtom *aLangGroup);
nsresult UpdateFontListInternal(bool aForce = false);
void AddFullnameEntries();
LangSupportEntry *GetLangSupportEntry(const FcChar8 *aLang,
bool aWithFonts);
// mFontsByFamily and mFontsByFullname contain entries only for families
// and fullnames for which there are fonts.
nsTHashtable<FontsByFcStrEntry> mFontsByFamily;
nsTHashtable<FontsByFullnameEntry> mFontsByFullname;
// mLangSupportTable contains an entry for each language that has been
// looked up through GetLangSupportEntry, even when the language is not
// supported.
nsTHashtable<LangSupportEntry> mLangSupportTable;
const nsTArray< nsCountedRef<FcPattern> > mEmptyPatternArray;
nsTArray<nsCString> mAliasForMultiFonts;
FcConfig *mLastConfig;
};
#endif /* GFX_FONTCONFIG_UTILS_H */