/* libs/graphics/ports/FontHostConfiguration_android.cpp
**
** Copyright 2011, The Android Open Source Project
**
** 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 "FontHostConfiguration_android.h"
#include "SkLanguage.h"
#include "SkTDArray.h"
#include "SkTypeface.h"
#include <expat.h>
#if !defined(SK_BUILD_FOR_ANDROID_NDK)
#include <cutils/properties.h>
#endif
#define SYSTEM_FONTS_FILE "/system/etc/system_fonts.xml"
#define FALLBACK_FONTS_FILE "/system/etc/fallback_fonts.xml"
#define VENDOR_FONTS_FILE "/vendor/etc/fallback_fonts.xml"
// These defines are used to determine the kind of tag that we're currently
// populating with data. We only care about the sibling tags nameset and fileset
// for now.
#define NO_TAG 0
#define NAMESET_TAG 1
#define FILESET_TAG 2
/**
* The FamilyData structure is passed around by the parser so that each handler
* can read these variables that are relevant to the current parsing.
*/
struct FamilyData {
FamilyData(XML_Parser *parserRef, SkTDArray<FontFamily*> &familiesRef) :
parser(parserRef), families(familiesRef), currentTag(NO_TAG) {};
XML_Parser *parser; // The expat parser doing the work
SkTDArray<FontFamily*> &families; // The array that each family is put into as it is parsed
FontFamily *currentFamily; // The current family being created
FontFileInfo *currentFontInfo; // The current fontInfo being created
int currentTag; // A flag to indicate whether we're in nameset/fileset tags
};
/**
* Handler for arbitrary text. This is used to parse the text inside each name
* or file tag. The resulting strings are put into the fNames or FontFileInfo arrays.
*/
void textHandler(void *data, const char *s, int len) {
FamilyData *familyData = (FamilyData*) data;
// Make sure we're in the right state to store this name information
if (familyData->currentFamily &&
(familyData->currentTag == NAMESET_TAG || familyData->currentTag == FILESET_TAG)) {
// Malloc new buffer to store the string
char *buff;
buff = (char*) malloc((len + 1) * sizeof(char));
strncpy(buff, s, len);
buff[len] = '\0';
switch (familyData->currentTag) {
case NAMESET_TAG:
*(familyData->currentFamily->fNames.append()) = buff;
break;
case FILESET_TAG:
if (familyData->currentFontInfo) {
familyData->currentFontInfo->fFileName = buff;
}
break;
default:
// Noop - don't care about any text that's not in the Fonts or Names list
break;
}
}
}
/**
* Handler for font files. This processes the attributes for language and
* variants then lets textHandler handle the actual file name
*/
void fontFileElementHandler(FamilyData *familyData, const char **attributes) {
FontFileInfo* newFileInfo = new FontFileInfo();
if (attributes) {
int currentAttributeIndex = 0;
while (attributes[currentAttributeIndex]) {
const char* attributeName = attributes[currentAttributeIndex];
const char* attributeValue = attributes[currentAttributeIndex+1];
int nameLength = strlen(attributeName);
int valueLength = strlen(attributeValue);
if (strncmp(attributeName, "variant", nameLength) == 0) {
if (strncmp(attributeValue, "elegant", valueLength) == 0) {
newFileInfo->fVariant = SkPaint::kElegant_Variant;
} else if (strncmp(attributeValue, "compact", valueLength) == 0) {
newFileInfo->fVariant = SkPaint::kCompact_Variant;
}
} else if (strncmp(attributeName, "lang", nameLength) == 0) {
newFileInfo->fLanguage = SkLanguage(attributeValue);
}
//each element is a pair of attributeName/attributeValue string pairs
currentAttributeIndex += 2;
}
}
*(familyData->currentFamily->fFontFileArray.append()) = newFileInfo;
familyData->currentFontInfo = newFileInfo;
XML_SetCharacterDataHandler(*familyData->parser, textHandler);
}
/**
* Handler for the start of a tag. The only tags we expect are family, nameset,
* fileset, name, and file.
*/
void startElementHandler(void *data, const char *tag, const char **atts) {
FamilyData *familyData = (FamilyData*) data;
int len = strlen(tag);
if (strncmp(tag, "family", len)== 0) {
familyData->currentFamily = new FontFamily();
familyData->currentFamily->order = -1;
// The Family tag has an optional "order" attribute with an integer value >= 0
// If this attribute does not exist, the default value is -1
for (int i = 0; atts[i] != NULL; i += 2) {
const char* attribute = atts[i];
const char* valueString = atts[i+1];
int value;
int len = sscanf(valueString, "%d", &value);
if (len > 0) {
familyData->currentFamily->order = value;
}
}
} else if (len == 7 && strncmp(tag, "nameset", len) == 0) {
familyData->currentTag = NAMESET_TAG;
} else if (len == 7 && strncmp(tag, "fileset", len) == 0) {
familyData->currentTag = FILESET_TAG;
} else if (strncmp(tag, "name", len) == 0 && familyData->currentTag == NAMESET_TAG) {
// If it's a Name, parse the text inside
XML_SetCharacterDataHandler(*familyData->parser, textHandler);
} else if (strncmp(tag, "file", len) == 0 && familyData->currentTag == FILESET_TAG) {
// If it's a file, parse the attributes, then parse the text inside
fontFileElementHandler(familyData, atts);
}
}
/**
* Handler for the end of tags. We only care about family, nameset, fileset,
* name, and file.
*/
void endElementHandler(void *data, const char *tag) {
FamilyData *familyData = (FamilyData*) data;
int len = strlen(tag);
if (strncmp(tag, "family", len)== 0) {
// Done parsing a Family - store the created currentFamily in the families array
*familyData->families.append() = familyData->currentFamily;
familyData->currentFamily = NULL;
} else if (len == 7 && strncmp(tag, "nameset", len) == 0) {
familyData->currentTag = NO_TAG;
} else if (len == 7 && strncmp(tag, "fileset", len) == 0) {
familyData->currentTag = NO_TAG;
} else if ((strncmp(tag, "name", len) == 0 && familyData->currentTag == NAMESET_TAG) ||
(strncmp(tag, "file", len) == 0 && familyData->currentTag == FILESET_TAG)) {
// Disable the arbitrary text handler installed to load Name data
XML_SetCharacterDataHandler(*familyData->parser, NULL);
}
}
/**
* This function parses the given filename and stores the results in the given
* families array.
*/
void parseConfigFile(const char *filename, SkTDArray<FontFamily*> &families) {
XML_Parser parser = XML_ParserCreate(NULL);
FamilyData *familyData = new FamilyData(&parser, families);
XML_SetUserData(parser, familyData);
XML_SetElementHandler(parser, startElementHandler, endElementHandler);
FILE *file = fopen(filename, "r");
// Some of the files we attempt to parse (in particular, /vendor/etc/fallback_fonts.xml)
// are optional - failure here is okay because one of these optional files may not exist.
if (file == NULL) {
return;
}
char buffer[512];
bool done = false;
while (!done) {
fgets(buffer, sizeof(buffer), file);
int len = strlen(buffer);
if (feof(file) != 0) {
done = true;
}
XML_Parse(parser, buffer, len, done);
}
fclose(file);
}
void getSystemFontFamilies(SkTDArray<FontFamily*> &fontFamilies) {
parseConfigFile(SYSTEM_FONTS_FILE, fontFamilies);
}
void getFallbackFontFamilies(SkTDArray<FontFamily*> &fallbackFonts) {
SkTDArray<FontFamily*> vendorFonts;
parseConfigFile(FALLBACK_FONTS_FILE, fallbackFonts);
parseConfigFile(VENDOR_FONTS_FILE, vendorFonts);
// This loop inserts the vendor fallback fonts in the correct order in the
// overall fallbacks list.
int currentOrder = -1;
for (int i = 0; i < vendorFonts.count(); ++i) {
FontFamily* family = vendorFonts[i];
int order = family->order;
if (order < 0) {
if (currentOrder < 0) {
// Default case - just add it to the end of the fallback list
*fallbackFonts.append() = family;
} else {
// no order specified on this font, but we're incrementing the order
// based on an earlier order insertion request
*fallbackFonts.insert(currentOrder++) = family;
}
} else {
// Add the font into the fallback list in the specified order. Set
// currentOrder for correct placement of other fonts in the vendor list.
*fallbackFonts.insert(order) = family;
currentOrder = order + 1;
}
}
}
/**
* Loads data on font families from various expected configuration files. The
* resulting data is returned in the given fontFamilies array.
*/
void getFontFamilies(SkTDArray<FontFamily*> &fontFamilies) {
SkTDArray<FontFamily*> fallbackFonts;
getSystemFontFamilies(fontFamilies);
getFallbackFontFamilies(fallbackFonts);
// Append all fallback fonts to system fonts
for (int i = 0; i < fallbackFonts.count(); ++i) {
*fontFamilies.append() = fallbackFonts[i];
}
}