Split custom font managers.

Some users would like to use the empty font manager, but the directory
gont manager brings in extra dependencies to work which would otherwise
be unneeded. Allow these users to build just the bits of code they
actually need.

Change-Id: Ib029ef2682883509bad5a2aa39f1ef55631f4d8a
Reviewed-on: https://skia-review.googlesource.com/8200
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>

1 files changed, 158 insertions, 0 deletions

diff --git a/src/ports/SkFontMgr_custom.h b/src/ports/SkFontMgr_custom.h
new file mode 100644
index 0000000000..9149378a50
--- /dev/null
+++ b/src/ports/SkFontMgr_custom.h
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2006 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkFontMgr_custom_DEFINED
+#define SkFontMgr_custom_DEFINED
+
+#include "SkFontHost_FreeType_common.h"
+#include "SkFontMgr.h"
+#include "SkFontStyle.h"
+#include "SkRefCnt.h"
+#include "SkString.h"
+#include "SkTArray.h"
+#include "SkTypes.h"
+
+class SkData;
+class SkFontDescriptor;
+class SkStreamAsset;
+class SkTypeface;
+
+/** The base SkTypeface implementation for the custom font manager. */
+class SkTypeface_Custom : public SkTypeface_FreeType {
+public:
+    SkTypeface_Custom(const SkFontStyle& style, bool isFixedPitch,
+                      bool sysFont, const SkString familyName, int index);
+    bool isSysFont() const;
+
+protected:
+    void onGetFamilyName(SkString* familyName) const override;
+    void onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocal) const override;
+    int getIndex() const;
+
+private:
+    const bool fIsSysFont;
+    const SkString fFamilyName;
+    const int fIndex;
+
+    typedef SkTypeface_FreeType INHERITED;
+};
+
+/** The empty SkTypeface implementation for the custom font manager.
+ *  Used as the last resort fallback typeface.
+ */
+class SkTypeface_Empty : public SkTypeface_Custom {
+public:
+    SkTypeface_Empty() ;
+
+protected:
+    SkStreamAsset* onOpenStream(int*) const override;
+
+private:
+    typedef SkTypeface_Custom INHERITED;
+};
+
+/** The stream SkTypeface implementation for the custom font manager. */
+class SkTypeface_Stream : public SkTypeface_Custom {
+public:
+    SkTypeface_Stream(std::unique_ptr<SkFontData> fontData,
+                      const SkFontStyle& style, bool isFixedPitch, bool sysFont,
+                      const SkString familyName);
+
+protected:
+    SkStreamAsset* onOpenStream(int* ttcIndex) const override;
+    std::unique_ptr<SkFontData> onMakeFontData() const override;
+
+private:
+    const std::unique_ptr<const SkFontData> fData;
+
+    typedef SkTypeface_Custom INHERITED;
+};
+
+/** The file SkTypeface implementation for the custom font manager. */
+class SkTypeface_File : public SkTypeface_Custom {
+public:
+    SkTypeface_File(const SkFontStyle& style, bool isFixedPitch, bool sysFont,
+                    const SkString familyName, const char path[], int index);
+
+protected:
+    SkStreamAsset* onOpenStream(int* ttcIndex) const override;
+
+private:
+    SkString fPath;
+
+    typedef SkTypeface_Custom INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+/**
+ *  SkFontStyleSet_Custom
+ *
+ *  This class is used by SkFontMgr_Custom to hold SkTypeface_Custom families.
+ */
+class SkFontStyleSet_Custom : public SkFontStyleSet {
+public:
+    explicit SkFontStyleSet_Custom(const SkString familyName);
+
+    /** Should only be called during the inital build phase. */
+    void appendTypeface(sk_sp<SkTypeface_Custom> typeface);
+    int count() override;
+    void getStyle(int index, SkFontStyle* style, SkString* name) override;
+    SkTypeface* createTypeface(int index) override;
+    SkTypeface* matchStyle(const SkFontStyle& pattern) override;
+    SkString getFamilyName();
+
+private:
+    SkTArray<sk_sp<SkTypeface_Custom>> fStyles;
+    SkString fFamilyName;
+
+    friend class SkFontMgr_Custom;
+};
+
+/**
+ *  SkFontMgr_Custom
+ *
+ *  This class is essentially a collection of SkFontStyleSet_Custom,
+ *  one SkFontStyleSet_Custom for each family. This class may be modified
+ *  to load fonts from any source by changing the initialization.
+ */
+class SkFontMgr_Custom : public SkFontMgr {
+public:
+    typedef SkTArray<sk_sp<SkFontStyleSet_Custom>> Families;
+    class SystemFontLoader {
+    public:
+        virtual ~SystemFontLoader() { }
+        virtual void loadSystemFonts(const SkTypeface_FreeType::Scanner&, Families*) const = 0;
+    };
+    explicit SkFontMgr_Custom(const SystemFontLoader& loader);
+
+protected:
+    int onCountFamilies() const override;
+    void onGetFamilyName(int index, SkString* familyName) const override;
+    SkFontStyleSet_Custom* onCreateStyleSet(int index) const override;
+    SkFontStyleSet_Custom* onMatchFamily(const char familyName[]) const override;
+    SkTypeface* onMatchFamilyStyle(const char familyName[],
+                                   const SkFontStyle& fontStyle) const override;
+    SkTypeface* onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
+                                            const char* bcp47[], int bcp47Count,
+                                            SkUnichar character) const override;
+    SkTypeface* onMatchFaceStyle(const SkTypeface* familyMember,
+                                 const SkFontStyle& fontStyle) const override;
+    SkTypeface* onCreateFromData(SkData* data, int ttcIndex) const override;
+    SkTypeface* onCreateFromStream(SkStreamAsset* bareStream, int ttcIndex) const override;
+    SkTypeface* onCreateFromStream(SkStreamAsset* s, const FontParameters& params) const override;
+    SkTypeface* onCreateFromFontData(std::unique_ptr<SkFontData> data) const override;
+    SkTypeface* onCreateFromFile(const char path[], int ttcIndex) const override;
+    SkTypeface* onLegacyCreateTypeface(const char familyName[], SkFontStyle style) const override;
+
+private:
+    Families fFamilies;
+    SkFontStyleSet_Custom* fDefaultFamily;
+    SkTypeface_FreeType::Scanner fScanner;
+};
+
+#endif