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Diffstat (limited to 'skia/ports/SkFontHost_android.cpp')
| -rw-r--r-- | skia/ports/SkFontHost_android.cpp | 578 |
1 files changed, 578 insertions, 0 deletions
diff --git a/skia/ports/SkFontHost_android.cpp b/skia/ports/SkFontHost_android.cpp new file mode 100644 index 0000000..d7613c6 --- /dev/null +++ b/skia/ports/SkFontHost_android.cpp @@ -0,0 +1,578 @@ +/* libs/graphics/ports/SkFontHost_android.cpp +** +** Copyright 2006, Google Inc. +** +** Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 +** +** Unless required by applicable law or agreed to in writing, software +** distributed under the License is distributed on an "AS IS" BASIS, +** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +** See the License for the specific language governing permissions and +** limitations under the License. +*/ + +#include "SkFontHost.h" +#include "SkDescriptor.h" +#include "SkMMapStream.h" +#include "SkPaint.h" +#include "SkString.h" +#include "SkStream.h" +#include "SkThread.h" +#include "SkTSearch.h" +#include <stdio.h> + +#define FONT_CACHE_MEMORY_BUDGET (768 * 1024) + +#ifndef SK_FONT_FILE_PREFIX + #define SK_FONT_FILE_PREFIX "/fonts/" +#endif + +SkTypeface::Style find_name_and_style(SkStream* stream, SkString* name); + +static void GetFullPathForSysFonts(SkString* full, const char name[]) +{ + full->set(getenv("ANDROID_ROOT")); + full->append(SK_FONT_FILE_PREFIX); + full->append(name); +} + +/////////////////////////////////////////////////////////////////////////////// + +struct FamilyRec; + +/* This guy holds a mapping of a name -> family, used for looking up fonts. + Since it is stored in a stretchy array that doesn't preserve object + semantics, we don't use constructor/destructors, but just have explicit + helpers to manage our internal bookkeeping. +*/ +struct NameFamilyPair { + const char* fName; // we own this + FamilyRec* fFamily; // we don't own this, we just reference it + + void construct(const char name[], FamilyRec* family) + { + fName = strdup(name); + fFamily = family; // we don't own this, so just record the referene + } + void destruct() + { + free((char*)fName); + // we don't own family, so just ignore our reference + } +}; + +// we use atomic_inc to grow this for each typeface we create +static int32_t gUniqueFontID; + +// this is the mutex that protects these globals +static SkMutex gFamilyMutex; +static FamilyRec* gFamilyHead; +static SkTDArray<NameFamilyPair> gNameList; + +struct FamilyRec { + FamilyRec* fNext; + SkTypeface* fFaces[4]; + + FamilyRec() + { + fNext = gFamilyHead; + memset(fFaces, 0, sizeof(fFaces)); + gFamilyHead = this; + } +}; + +static SkTypeface* find_best_face(const FamilyRec* family, + SkTypeface::Style style) +{ + SkTypeface* const* faces = family->fFaces; + + if (faces[style] != NULL) { // exact match + return faces[style]; + } + // look for a matching bold + style = (SkTypeface::Style)(style ^ SkTypeface::kItalic); + if (faces[style] != NULL) { + return faces[style]; + } + // look for the plain + if (faces[SkTypeface::kNormal] != NULL) { + return faces[SkTypeface::kNormal]; + } + // look for anything + for (int i = 0; i < 4; i++) { + if (faces[i] != NULL) { + return faces[i]; + } + } + // should never get here, since the faces list should not be empty + SkASSERT(!"faces list is empty"); + return NULL; +} + +static FamilyRec* find_family(const SkTypeface* member) +{ + FamilyRec* curr = gFamilyHead; + while (curr != NULL) { + for (int i = 0; i < 4; i++) { + if (curr->fFaces[i] == member) { + return curr; + } + } + curr = curr->fNext; + } + return NULL; +} + +static SkTypeface* resolve_uniqueID(uint32_t uniqueID) +{ + FamilyRec* curr = gFamilyHead; + while (curr != NULL) { + for (int i = 0; i < 4; i++) { + SkTypeface* face = curr->fFaces[i]; + if (face != NULL && face->uniqueID() == uniqueID) { + return face; + } + } + curr = curr->fNext; + } + return NULL; +} + +/* Remove reference to this face from its family. If the resulting family + is empty (has no faces), return that family, otherwise return NULL +*/ +static FamilyRec* remove_from_family(const SkTypeface* face) +{ + FamilyRec* family = find_family(face); + SkASSERT(family->fFaces[face->style()] == face); + family->fFaces[face->style()] = NULL; + + for (int i = 0; i < 4; i++) { + if (family->fFaces[i] != NULL) { // family is non-empty + return NULL; + } + } + return family; // return the empty family +} + +// maybe we should make FamilyRec be doubly-linked +static void detach_and_delete_family(FamilyRec* family) +{ + FamilyRec* curr = gFamilyHead; + FamilyRec* prev = NULL; + + while (curr != NULL) { + FamilyRec* next = curr->fNext; + if (curr == family) { + if (prev == NULL) { + gFamilyHead = next; + } else { + prev->fNext = next; + } + SkDELETE(family); + return; + } + prev = curr; + curr = next; + } + SkASSERT(!"Yikes, couldn't find family in our list to remove/delete"); +} + +static SkTypeface* find_typeface(const char name[], SkTypeface::Style style) +{ + NameFamilyPair* list = gNameList.begin(); + int count = gNameList.count(); + + int index = SkStrLCSearch(&list[0].fName, count, name, sizeof(list[0])); + + if (index >= 0) { + return find_best_face(list[index].fFamily, style); + } + return NULL; +} + +static SkTypeface* find_typeface(const SkTypeface* familyMember, + SkTypeface::Style style) +{ + const FamilyRec* family = find_family(familyMember); + return family ? find_best_face(family, style) : NULL; +} + +static void add_name(const char name[], FamilyRec* family) +{ + SkAutoAsciiToLC tolc(name); + name = tolc.lc(); + + NameFamilyPair* list = gNameList.begin(); + int count = gNameList.count(); + + int index = SkStrLCSearch(&list[0].fName, count, name, sizeof(list[0])); + + if (index < 0) { + list = gNameList.insert(~index); + list->construct(name, family); + } +} + +static void remove_from_names(FamilyRec* emptyFamily) +{ +#ifdef SK_DEBUG + for (int i = 0; i < 4; i++) { + SkASSERT(emptyFamily->fFaces[i] == NULL); + } +#endif + + SkTDArray<NameFamilyPair>& list = gNameList; + + // must go backwards when removing + for (int i = list.count() - 1; i >= 0; --i) { + NameFamilyPair* pair = &list[i]; + if (pair->fFamily == emptyFamily) { + pair->destruct(); + list.remove(i); + } + } +} + +/////////////////////////////////////////////////////////////////////////////// + +class FamilyTypeface : public SkTypeface { +public: + FamilyTypeface(Style style, bool sysFont, SkTypeface* familyMember) + : SkTypeface(style, sk_atomic_inc(&gUniqueFontID) + 1) + { + fIsSysFont = sysFont; + + SkAutoMutexAcquire ac(gFamilyMutex); + + FamilyRec* rec = NULL; + if (familyMember) { + rec = find_family(familyMember); + SkASSERT(rec); + } else { + rec = SkNEW(FamilyRec); + } + rec->fFaces[style] = this; + } + + virtual ~FamilyTypeface() + { + SkAutoMutexAcquire ac(gFamilyMutex); + + // remove us from our family. If the family is now empty, we return + // that and then remove that family from the name list + FamilyRec* family = remove_from_family(this); + if (NULL != family) { + remove_from_names(family); + detach_and_delete_family(family); + } + } + + bool isSysFont() const { return fIsSysFont; } + + virtual SkStream* openStream() = 0; + virtual void closeStream(SkStream*) = 0; + +private: + bool fIsSysFont; + + typedef SkTypeface INHERITED; +}; + +/////////////////////////////////////////////////////////////////////////////// + +class StreamTypeface : public FamilyTypeface { +public: + StreamTypeface(Style style, bool sysFont, SkTypeface* familyMember, + SkStream* stream) + : INHERITED(style, sysFont, familyMember) + { + fStream = stream; + } + virtual ~StreamTypeface() + { + SkDELETE(fStream); + } + + // overrides + virtual SkStream* openStream() { return fStream; } + virtual void closeStream(SkStream*) {} + +private: + SkStream* fStream; + + typedef FamilyTypeface INHERITED; +}; + +class FileTypeface : public FamilyTypeface { +public: + FileTypeface(Style style, bool sysFont, SkTypeface* familyMember, + const char path[]) + : INHERITED(style, sysFont, familyMember) + { + SkString fullpath; + + if (sysFont) { + GetFullPathForSysFonts(&fullpath, path); + path = fullpath.c_str(); + } + fPath.set(path); + } + + // overrides + virtual SkStream* openStream() + { + SkStream* stream = SkNEW_ARGS(SkMMAPStream, (fPath.c_str())); + + // check for failure + if (stream->getLength() <= 0) { + SkDELETE(stream); + // maybe MMAP isn't supported. try FILE + stream = SkNEW_ARGS(SkFILEStream, (fPath.c_str())); + if (stream->getLength() <= 0) { + SkDELETE(stream); + stream = NULL; + } + } + return stream; + } + virtual void closeStream(SkStream* stream) + { + SkDELETE(stream); + } + +private: + SkString fPath; + + typedef FamilyTypeface INHERITED; +}; + +/////////////////////////////////////////////////////////////////////////////// +/////////////////////////////////////////////////////////////////////////////// + +static bool get_name_and_style(const char path[], SkString* name, + SkTypeface::Style* style) +{ + SkString fullpath; + GetFullPathForSysFonts(&fullpath, path); + + SkMMAPStream stream(fullpath.c_str()); + if (stream.getLength() > 0) { + *style = find_name_and_style(&stream, name); + return true; + } + else { + SkFILEStream stream(fullpath.c_str()); + if (stream.getLength() > 0) { + *style = find_name_and_style(&stream, name); + return true; + } + } + + SkDebugf("---- failed to open <%s> as a font\n", fullpath.c_str()); + return false; +} + +struct FontInitRec { + const char* fFileName; + const char* const* fNames; // null-terminated list +}; + +static const char* gSansNames[] = { + "sans-serif", "arial", "helvetica", "tahoma", "verdana", NULL +}; + +static const char* gSerifNames[] = { + "serif", "times", "times new roman", "palatino", "goudy", + "fantasy", "cursive", NULL +}; + +static const char* gMonoNames[] = { + "monospace", "courier", "courier new", "monaco", NULL +}; + +static const char* gFBNames[] = { NULL }; + +/* Fonts must be grouped by family, with the first font in a family having the + list of names (even if that list is empty), and the following members having + null for the list. The names list must be NULL-terminated +*/ +static const FontInitRec gSystemFonts[] = { + { "DroidSans.ttf", gSansNames }, + { "DroidSans-Bold.ttf", NULL }, + { "DroidSerif-Regular.ttf", gSerifNames }, + { "DroidSerif-Bold.ttf", NULL }, + { "DroidSerif-Italic.ttf", NULL }, + { "DroidSerif-BoldItalic.ttf", NULL }, + { "DroidSansMono.ttf", gMonoNames }, + { "DroidSansFallback.ttf", gFBNames } +}; + +#define DEFAULT_NAMES gSansNames + +// these globals are assigned (once) by load_system_fonts() +static SkTypeface* gFallBackTypeface; +static FamilyRec* gDefaultFamily; +static SkTypeface* gDefaultNormal; + +static void load_system_fonts() +{ + // check if we've already be called + if (NULL != gDefaultNormal) { + return; + } + + const FontInitRec* rec = gSystemFonts; + SkTypeface* firstInFamily = NULL; + + for (size_t i = 0; i < SK_ARRAY_COUNT(gSystemFonts); i++) { + // if we're the first in a new family, clear firstInFamily + if (rec[i].fNames != NULL) { + firstInFamily = NULL; + } + + SkString name; + SkTypeface::Style style; + + if (!get_name_and_style(rec[i].fFileName, &name, &style)) { + SkDebugf("------ can't load <%s> as a font\n", rec[i].fFileName); + continue; + } + + SkTypeface* tf = SkNEW_ARGS(FileTypeface, + (style, + true, // system-font (cannot delete) + firstInFamily, // what family to join + rec[i].fFileName) // filename + ); + + if (rec[i].fNames != NULL) { + firstInFamily = tf; + const char* const* names = rec[i].fNames; + + // record the fallback if this is it + if (names == gFBNames) { + gFallBackTypeface = tf; + } + // record the default family if this is it + if (names == DEFAULT_NAMES) { + gDefaultFamily = find_family(tf); + } + // add the names to map to this family + FamilyRec* family = find_family(tf); + while (*names) { + add_name(*names, family); + names += 1; + } + } + + } + + // do this after all fonts are loaded. This is our default font, and it + // acts as a sentinel so we only execute load_system_fonts() once + gDefaultNormal = find_best_face(gDefaultFamily, SkTypeface::kNormal); +} + +/////////////////////////////////////////////////////////////////////////////// + +SkTypeface* SkFontHost::FindTypeface(const SkTypeface* familyFace, + const char familyName[], + SkTypeface::Style style) +{ + load_system_fonts(); + + SkAutoMutexAcquire ac(gFamilyMutex); + + // clip to legal style bits + style = (SkTypeface::Style)(style & SkTypeface::kBoldItalic); + + SkTypeface* tf = NULL; + + if (NULL != familyFace) { + tf = find_typeface(familyFace, style); + } else if (NULL != familyName) { + tf = find_typeface(familyName, style); + } + + if (NULL == tf) { + tf = find_best_face(gDefaultFamily, style); + } + + return tf; +} + +SkTypeface* SkFontHost::ResolveTypeface(uint32_t fontID) +{ + SkAutoMutexAcquire ac(gFamilyMutex); + + return resolve_uniqueID(fontID); +} + +SkStream* SkFontHost::OpenStream(uint32_t fontID) +{ + + FamilyTypeface* tf = (FamilyTypeface*)SkFontHost::ResolveTypeface(fontID); + SkStream* stream = tf ? tf->openStream() : NULL; + + if (NULL == stream || stream->getLength() == 0) { + delete stream; + stream = NULL; + } + return stream; +} + +void SkFontHost::CloseStream(uint32_t fontID, SkStream* stream) +{ + FamilyTypeface* tf = (FamilyTypeface*)SkFontHost::ResolveTypeface(fontID); + if (NULL != tf) { + tf->closeStream(stream); + } +} + +SkScalerContext* SkFontHost::CreateFallbackScalerContext( + const SkScalerContext::Rec& rec) +{ + load_system_fonts(); + + SkAutoDescriptor ad(sizeof(rec) + SkDescriptor::ComputeOverhead(1)); + SkDescriptor* desc = ad.getDesc(); + + desc->init(); + SkScalerContext::Rec* newRec = + (SkScalerContext::Rec*)desc->addEntry(kRec_SkDescriptorTag, + sizeof(rec), &rec); + newRec->fFontID = gFallBackTypeface->uniqueID(); + desc->computeChecksum(); + + return SkFontHost::CreateScalerContext(desc); +} + +/////////////////////////////////////////////////////////////////////////////// + +SkTypeface* SkFontHost::CreateTypeface(SkStream* stream) +{ + if (NULL == stream || stream->getLength() <= 0) { + SkDELETE(stream); + return NULL; + } + + SkString name; + SkTypeface::Style style = find_name_and_style(stream, &name); + + return SkNEW_ARGS(StreamTypeface, (style, false, NULL, stream)); +} + +/////////////////////////////////////////////////////////////////////////////// + +size_t SkFontHost::ShouldPurgeFontCache(size_t sizeAllocatedSoFar) +{ + if (sizeAllocatedSoFar > FONT_CACHE_MEMORY_BUDGET) + return sizeAllocatedSoFar - FONT_CACHE_MEMORY_BUDGET; + else + return 0; // nothing to do +} + |