src/ports/FontHostConfiguration_android.cpp - platform/external/skia - Git at Google

 /* 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 <expat.h>
 #include "SkTDArray.h"

 #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
     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 fFileNames 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:
             *(familyData->currentFamily->fFileNames.append()) = buff;
             break;
         default:
             // Noop - don't care about any text that's not in the Fonts or Names list
             break;
         }
     }
 }

 /**
  * 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) ||
             (strncmp(tag, "file", len) == 0 && familyData->currentTag == FILESET_TAG)) {
         // If it's a Name, parse the text inside
         XML_SetCharacterDataHandler(*familyData->parser, textHandler);
     }
 }

 /**
  * 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);
     }
 }

 /**
  * 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;
     SkTDArray<FontFamily*> vendorFonts;
     parseConfigFile(SYSTEM_FONTS_FILE, fontFamilies);
     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;
         }
     }
     // Append all fallback fonts to system fonts
     for (int i = 0; i < fallbackFonts.count(); ++i) {
         *fontFamilies.append() = fallbackFonts[i];
     }
 }
	/* 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 <expat.h>
	#include "SkTDArray.h"

	#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
	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 fFileNames 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:
	*(familyData->currentFamily->fFileNames.append()) = buff;
	break;
	default:
	// Noop - don't care about any text that's not in the Fonts or Names list
	break;
	}
	}
	}

	/**
	* 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) \|\|
	(strncmp(tag, "file", len) == 0 && familyData->currentTag == FILESET_TAG)) {
	// If it's a Name, parse the text inside
	XML_SetCharacterDataHandler(*familyData->parser, textHandler);
	}
	}

	/**
	* 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);
	}
	}

	/**
	* 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;
	SkTDArray<FontFamily*> vendorFonts;
	parseConfigFile(SYSTEM_FONTS_FILE, fontFamilies);
	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;
	}
	}
	// Append all fallback fonts to system fonts
	for (int i = 0; i < fallbackFonts.count(); ++i) {
	*fontFamilies.append() = fallbackFonts[i];
	}
	}