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, 104 insertions, 0 deletions

diff --git a/src/ports/SkFontMgr_custom_directory.cpp b/src/ports/SkFontMgr_custom_directory.cpp
new file mode 100644
index 0000000000..af322875f3
--- /dev/null
+++ b/src/ports/SkFontMgr_custom_directory.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkFontMgr_custom.h"
+#include "SkFontMgr_directory.h"
+#include "SkOSFile.h"
+#include "SkOSPath.h"
+#include "SkStream.h"
+
+class DirectorySystemFontLoader : public SkFontMgr_Custom::SystemFontLoader {
+public:
+    DirectorySystemFontLoader(const char* dir) : fBaseDirectory(dir) { }
+
+    void loadSystemFonts(const SkTypeface_FreeType::Scanner& scanner,
+                         SkFontMgr_Custom::Families* families) const override
+    {
+        load_directory_fonts(scanner, fBaseDirectory, ".ttf", families);
+        load_directory_fonts(scanner, fBaseDirectory, ".ttc", families);
+        load_directory_fonts(scanner, fBaseDirectory, ".otf", families);
+        load_directory_fonts(scanner, fBaseDirectory, ".pfb", families);
+
+        if (families->empty()) {
+            SkFontStyleSet_Custom* family = new SkFontStyleSet_Custom(SkString());
+            families->push_back().reset(family);
+            family->appendTypeface(sk_make_sp<SkTypeface_Empty>());
+        }
+    }
+
+private:
+    static SkFontStyleSet_Custom* find_family(SkFontMgr_Custom::Families& families,
+                                              const char familyName[])
+    {
+       for (int i = 0; i < families.count(); ++i) {
+            if (families[i]->getFamilyName().equals(familyName)) {
+                return families[i].get();
+            }
+        }
+        return nullptr;
+    }
+
+    static void load_directory_fonts(const SkTypeface_FreeType::Scanner& scanner,
+                                     const SkString& directory, const char* suffix,
+                                     SkFontMgr_Custom::Families* families)
+    {
+        SkOSFile::Iter iter(directory.c_str(), suffix);
+        SkString name;
+
+        while (iter.next(&name, false)) {
+            SkString filename(SkOSPath::Join(directory.c_str(), name.c_str()));
+            std::unique_ptr<SkStreamAsset> stream = SkStream::MakeFromFile(filename.c_str());
+            if (!stream) {
+                SkDebugf("---- failed to open <%s>\n", filename.c_str());
+                continue;
+            }
+
+            int numFaces;
+            if (!scanner.recognizedFont(stream.get(), &numFaces)) {
+                SkDebugf("---- failed to open <%s> as a font\n", filename.c_str());
+                continue;
+            }
+
+            for (int faceIndex = 0; faceIndex < numFaces; ++faceIndex) {
+                bool isFixedPitch;
+                SkString realname;
+                SkFontStyle style = SkFontStyle(); // avoid uninitialized warning
+                if (!scanner.scanFont(stream.get(), faceIndex,
+                                      &realname, &style, &isFixedPitch, nullptr))
+                {
+                    SkDebugf("---- failed to open <%s> <%d> as a font\n",
+                             filename.c_str(), faceIndex);
+                    continue;
+                }
+
+                SkFontStyleSet_Custom* addTo = find_family(*families, realname.c_str());
+                if (nullptr == addTo) {
+                    addTo = new SkFontStyleSet_Custom(realname);
+                    families->push_back().reset(addTo);
+                }
+                addTo->appendTypeface(sk_make_sp<SkTypeface_File>(style, isFixedPitch, true,
+                                                                  realname, filename.c_str(),
+                                                                  faceIndex));
+            }
+        }
+
+        SkOSFile::Iter dirIter(directory.c_str());
+        while (dirIter.next(&name, true)) {
+            if (name.startsWith(".")) {
+                continue;
+            }
+            SkString dirname(SkOSPath::Join(directory.c_str(), name.c_str()));
+            load_directory_fonts(scanner, dirname, suffix, families);
+        }
+    }
+
+    SkString fBaseDirectory;
+};
+
+SK_API sk_sp<SkFontMgr> SkFontMgr_New_Custom_Directory(const char* dir) {
+    return sk_make_sp<SkFontMgr_Custom>(DirectorySystemFontLoader(dir));
+}