/*
* 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.
*/
#include "SkFontHost.h"
#include "SkFontDescriptor.h"
#include "SkDescriptor.h"
#include "SkMMapStream.h"
#include "SkOSFile.h"
#include "SkPaint.h"
#include "SkString.h"
#include "SkStream.h"
#include "SkThread.h"
#include "SkTSearch.h"
#ifndef SK_FONT_FILE_PREFIX
#define SK_FONT_FILE_PREFIX "/usr/share/fonts/truetype/"
#endif
#ifndef SK_FONT_FILE_DIR_SEPERATOR
#define SK_FONT_FILE_DIR_SEPERATOR "/"
#endif
bool find_name_and_attributes(SkStream* stream, SkString* name,
SkTypeface::Style* style, bool* isFixedWidth);
///////////////////////////////////////////////////////////////////////////////
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
SK_DECLARE_STATIC_MUTEX(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
SkDEBUGFAIL("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* find_from_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;
}
SkDEBUGFAIL("Yikes, couldn't find family in our list to remove/delete");
}
static const char* find_family_name(const SkTypeface* familyMember) {
const FamilyRec* familyRec = find_family(familyMember);
for (int i = 0; i < gNameList.count(); i++) {
if (gNameList[i].fFamily == familyRec) {
return gNameList[i].fName;
}
}
return NULL;
}
static FamilyRec* find_familyrec(const char name[]) {
const NameFamilyPair* list = gNameList.begin();
int index = SkStrLCSearch(&list[0].fName, gNameList.count(), name,
sizeof(list[0]));
return index >= 0 ? list[index].fFamily : NULL;
}
static SkTypeface* find_typeface(const char name[], SkTypeface::Style style) {
FamilyRec* rec = find_familyrec(name);
return rec ? find_best_face(rec, style) : 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, FamilyRec* family, bool isFixedWidth)
: SkTypeface(style, sk_atomic_inc(&gUniqueFontID) + 1, isFixedWidth) {
fIsSysFont = sysFont;
SkAutoMutexAcquire ac(gFamilyMutex);
if (NULL == family) {
family = SkNEW(FamilyRec);
}
family->fFaces[style] = this;
fFamilyRec = family; // just record it so we can return it if asked
}
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; }
FamilyRec* getFamily() const { return fFamilyRec; }
// openStream returns a SkStream that has been ref-ed
virtual SkStream* openStream() = 0;
virtual const char* getUniqueString() const = 0;
private:
FamilyRec* fFamilyRec; // we don't own this, just point to it
bool fIsSysFont;
typedef SkTypeface INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
/* This subclass is just a place holder for when we have no fonts available.
It exists so that our globals (e.g. gFamilyHead) that expect *something*
will not be null.
*/
class EmptyTypeface : public FamilyTypeface {
public:
EmptyTypeface() : INHERITED(SkTypeface::kNormal, true, NULL, false) {}
// overrides
virtual SkStream* openStream() { return NULL; }
virtual const char* getUniqueString() const { return NULL; }
private:
typedef FamilyTypeface INHERITED;
};
class StreamTypeface : public FamilyTypeface {
public:
StreamTypeface(Style style, bool sysFont, FamilyRec* family,
SkStream* stream, bool isFixedWidth)
: INHERITED(style, sysFont, family, isFixedWidth) {
stream->ref();
fStream = stream;
}
virtual ~StreamTypeface() {
fStream->unref();
}
// overrides
virtual SkStream* openStream()
{
// openStream returns a refed stream.
fStream->ref();
return fStream;
}
virtual const char* getUniqueString() const { return NULL; }
private:
SkStream* fStream;
typedef FamilyTypeface INHERITED;
};
class FileTypeface : public FamilyTypeface {
public:
FileTypeface(Style style, bool sysFont, FamilyRec* family,
const char path[], bool isFixedWidth)
: INHERITED(style, sysFont, family, isFixedWidth) {
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 const char* getUniqueString() const {
const char* str = strrchr(fPath.c_str(), '/');
if (str) {
str += 1; // skip the '/'
}
return str;
}
private:
SkString fPath;
typedef FamilyTypeface INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
static bool get_name_and_style(const char path[], SkString* name,
SkTypeface::Style* style, bool* isFixedWidth) {
SkMMAPStream stream(path);
if (stream.getLength() > 0) {
return find_name_and_attributes(&stream, name, style, isFixedWidth);
}
else {
SkFILEStream stream(path);
if (stream.getLength() > 0) {
return find_name_and_attributes(&stream, name, style, isFixedWidth);
}
}
SkDebugf("---- failed to open <%s> as a font\n", path);
return false;
}
// these globals are assigned (once) by load_system_fonts()
static SkTypeface* gFallBackTypeface;
static FamilyRec* gDefaultFamily;
static SkTypeface* gDefaultNormal;
static void load_directory_fonts(const SkString& directory, unsigned int* count) {
SkOSFile::Iter iter(directory.c_str(), ".ttf");
SkString name;
while (iter.next(&name, false)) {
SkString filename(directory);
filename.append(name);
bool isFixedWidth;
SkString realname;
SkTypeface::Style style = SkTypeface::kNormal; // avoid uninitialized warning
if (!get_name_and_style(filename.c_str(), &realname, &style, &isFixedWidth)) {
SkDebugf("------ can't load <%s> as a font\n", filename.c_str());
continue;
}
FamilyRec* family = find_familyrec(realname.c_str());
if (family && family->fFaces[style]) {
continue;
}
// this constructor puts us into the global gFamilyHead llist
FamilyTypeface* tf = SkNEW_ARGS(FileTypeface,
(style,
true, // system-font (cannot delete)
family, // what family to join
filename.c_str(),
isFixedWidth) // filename
);
if (NULL == family) {
add_name(realname.c_str(), tf->getFamily());
}
*count += 1;
}
SkOSFile::Iter dirIter(directory.c_str());
while (dirIter.next(&name, true)) {
if (name.startsWith(".")) {
continue;
}
SkString dirname(directory);
dirname.append(name);
dirname.append(SK_FONT_FILE_DIR_SEPERATOR);
load_directory_fonts(dirname, count);
}
}
static void load_system_fonts() {
// check if we've already be called
if (NULL != gDefaultNormal) {
return;
}
SkString baseDirectory(SK_FONT_FILE_PREFIX);
unsigned int count = 0;
load_directory_fonts(baseDirectory, &count);
if (0 == count) {
SkNEW(EmptyTypeface);
}
// 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
static const char* gDefaultNames[] = {
"Arial", "Verdana", "Times New Roman", NULL
};
const char** names = gDefaultNames;
while (*names) {
SkTypeface* tf = find_typeface(*names++, SkTypeface::kNormal);
if (tf) {
gDefaultNormal = tf;
break;
}
}
// check if we found *something*
if (NULL == gDefaultNormal) {
if (NULL == gFamilyHead) {
sk_throw();
}
for (int i = 0; i < 4; i++) {
if ((gDefaultNormal = gFamilyHead->fFaces[i]) != NULL) {
break;
}
}
}
if (NULL == gDefaultNormal) {
sk_throw();
}
gFallBackTypeface = gDefaultNormal;
gDefaultFamily = find_family(gDefaultNormal);
}
///////////////////////////////////////////////////////////////////////////////
void SkFontHost::Serialize(const SkTypeface* face, SkWStream* stream) {
SkFontDescriptor descriptor;
descriptor.setFamilyName(find_family_name(face));
descriptor.setStyle(face->style());
descriptor.setFontFileName(((FamilyTypeface*)face)->getUniqueString());
descriptor.serialize(stream);
const bool isCustomFont = !((FamilyTypeface*)face)->isSysFont();
if (isCustomFont) {
// store the entire font in the fontData
SkStream* fontStream = ((FamilyTypeface*)face)->openStream();
const uint32_t length = fontStream->getLength();
stream->writePackedUInt(length);
stream->writeStream(fontStream, length);
fontStream->unref();
} else {
stream->writePackedUInt(0);
}
}
SkTypeface* SkFontHost::Deserialize(SkStream* stream) {
load_system_fonts();
SkFontDescriptor descriptor(stream);
const char* familyName = descriptor.getFamilyName();
const SkTypeface::Style style = descriptor.getStyle();
const uint32_t customFontDataLength = stream->readPackedUInt();
if (customFontDataLength > 0) {
// generate a new stream to store the custom typeface
SkMemoryStream* fontStream = new SkMemoryStream(customFontDataLength - 1);
stream->read((void*)fontStream->getMemoryBase(), customFontDataLength - 1);
SkTypeface* face = CreateTypefaceFromStream(fontStream);
fontStream->unref();
return face;
}
return SkFontHost::CreateTypeface(NULL, familyName, style);
}
///////////////////////////////////////////////////////////////////////////////
SkTypeface* SkFontHost::CreateTypeface(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) {
// SkDebugf("======= familyName <%s>\n", familyName);
tf = find_typeface(familyName, style);
}
if (NULL == tf) {
tf = find_best_face(gDefaultFamily, style);
}
SkSafeRef(tf);
return tf;
}
SkStream* SkFontHost::OpenStream(uint32_t fontID) {
FamilyTypeface* tf = (FamilyTypeface*)find_from_uniqueID(fontID);
SkStream* stream = tf ? tf->openStream() : NULL;
if (stream && stream->getLength() == 0) {
stream->unref();
stream = NULL;
}
return stream;
}
size_t SkFontHost::GetFileName(SkFontID fontID, char path[], size_t length,
int32_t* index) {
// SkDebugf("SkFontHost::GetFileName unimplemented\n");
return 0;
}
SkFontID SkFontHost::NextLogicalFont(SkFontID currFontID, SkFontID origFontID) {
return 0;
}
///////////////////////////////////////////////////////////////////////////////
SkTypeface* SkFontHost::CreateTypefaceFromStream(SkStream* stream) {
if (NULL == stream || stream->getLength() <= 0) {
SkDELETE(stream);
return NULL;
}
bool isFixedWidth;
SkTypeface::Style style;
if (find_name_and_attributes(stream, NULL, &style, &isFixedWidth)) {
return SkNEW_ARGS(StreamTypeface, (style, false, NULL, stream, isFixedWidth));
} else {
return NULL;
}
}
SkTypeface* SkFontHost::CreateTypefaceFromFile(const char path[]) {
SkTypeface* face = NULL;
SkFILEStream* stream = SkNEW_ARGS(SkFILEStream, (path));
if (stream->isValid()) {
face = CreateTypefaceFromStream(stream);
}
stream->unref();
return face;
}