Simplified advanced detector file sys scanning code

svn-id: r33455

5 files changed, 332 insertions, 259 deletions

diff --git a/common/advancedDetector.cpp b/common/advancedDetector.cpp
index 6496315e2e..adc6f9e327 100644
--- a/common/advancedDetector.cpp
+++ b/common/advancedDetector.cpp
@@ -305,13 +305,14 @@ static void reportUnknown(const StringMap &filesMD5, const IntMap &filesSize) {
 	printf("\n");
 }
 
-static ADGameDescList detectGameFilebased(const FSList &fslist, const Common::ADParams &params, IntMap &allFiles);
+static ADGameDescList detectGameFilebased(const StringMap &allFiles, const Common::ADParams &params);
 
 static ADGameDescList detectGame(const FSList &fslist, const Common::ADParams &params, Language language, Platform platform, const Common::String extra) {
-	StringSet filesList;
+	StringMap allFiles;
+
+	StringSet detectFiles;
 	StringMap filesMD5;
 	IntMap filesSize;
-	IntMap allFiles;
 
 	const ADGameFileDescription *fileDesc;
 	const ADGameDescription *g;
@@ -319,16 +320,8 @@ static ADGameDescList detectGame(const FSList &fslist, const Common::ADParams &p
 
 	debug(3, "Starting detection");
 
-	// First we compose list of files which we need MD5s for
-	for (descPtr = params.descs; ((const ADGameDescription *)descPtr)->gameid != 0; descPtr += params.descItemSize) {
-		g = (const ADGameDescription *)descPtr;
-
-		for (fileDesc = g->filesDescriptions; fileDesc->fileName; fileDesc++) {
-			filesList[String(fileDesc->fileName)] = true;
-		}
-	}
-
-	// Get the information of the existing files
+	// First we compose an efficient to query set of all files in  fslist.
+	// Includes nifty stuff like removing trailing dots and ignoring case.
 	for (FSList::const_iterator file = fslist.begin(); file != fslist.end(); ++file) {
 		if (file->isDirectory())
 			continue;
@@ -339,23 +332,37 @@ static ADGameDescList detectGame(const FSList &fslist, const Common::ADParams &p
 		if (tstr.lastChar() == '.')
 			tstr.deleteLastChar();
 
-		allFiles[tstr] = true;	// Record the presence of this file
+		allFiles[tstr] = file->getPath();	// Record the presence of this file
+	}
 
-		debug(3, "+ %s", tstr.c_str());
+	// Compute the set of files for which we need MD5s for. I.e. files which are
+	// included in some ADGameDescription *and* present in fslist.
+	for (descPtr = params.descs; ((const ADGameDescription *)descPtr)->gameid != 0; descPtr += params.descItemSize) {
+		g = (const ADGameDescription *)descPtr;
 
-		if (!filesList.contains(tstr))
-			continue;
+		for (fileDesc = g->filesDescriptions; fileDesc->fileName; fileDesc++) {
+			String tstr = fileDesc->fileName;
+			if (allFiles.contains(tstr))
+				detectFiles[tstr] = true;
+		}
+	}
+
+	// Get the information for all detection files, if they exist
+	for (StringSet::const_iterator file = detectFiles.begin(); file != detectFiles.end(); ++file) {
+		String fname = file->_key;
+
+		debug(3, "+ %s", fname.c_str());
 
 		char md5str[32+1];
-		if (!md5_file_string(*file, md5str, params.md5Bytes))
+		if (!md5_file_string(allFiles[fname].c_str(), md5str, params.md5Bytes))
 			continue;
-		filesMD5[tstr] = md5str;
+		filesMD5[fname] = md5str;
 
-		debug(3, "> %s: %s", tstr.c_str(), md5str);
+		debug(3, "> %s: %s", fname.c_str(), md5str);
 
 		File testFile;
-		if (testFile.open(file->getPath())) {
-			filesSize[tstr] = (int32)testFile.size();
+		if (testFile.open(allFiles[fname])) {
+			filesSize[fname] = (int32)testFile.size();
 			testFile.close();
 		}
 	}
@@ -443,32 +450,16 @@ static ADGameDescList detectGame(const FSList &fslist, const Common::ADParams &p
 	
 		// Filename based fallback
 		if (params.fileBasedFallback != 0)
-			matched = detectGameFilebased(fslist, params, allFiles);
+			matched = detectGameFilebased(allFiles, params);
 	}
 
 	return matched;
 }
 
-static ADGameDescList detectGameFilebased(const FSList &fslist, const Common::ADParams &params, IntMap &allFiles) {
+static ADGameDescList detectGameFilebased(const StringMap &allFiles, const Common::ADParams &params) {
 	const ADFileBasedFallback *ptr;
 	const char* const* filenames;
 
-	// First we create list of files required for detection.
-	// The filenames can be different than the MD5 based match ones.
-	for (ptr = params.fileBasedFallback; ptr->desc; ++ptr) {
-		for (filenames = ptr->filenames; *filenames; ++filenames) {
-			String tstr = String(*filenames);
-
-			if (!allFiles.contains(tstr)) {
-				File testFile;
-				if (testFile.open(tstr) || testFile.open(tstr + ".")) {
-					allFiles[tstr] = true;
-					testFile.close();
-				}
-			}
-		}
-	}
-
 	// Then we perform the actual filename matching. If there are
 	// several matches, only the one with the maximum numbers of
 	// files is considered.
diff --git a/common/config-manager.cpp b/common/config-manager.cpp
index 044474a927..c5c7098d25 100644
--- a/common/config-manager.cpp
+++ b/common/config-manager.cpp
@@ -32,27 +32,10 @@
 #include "common/config-manager.h"
 #include "common/file.h"
 #include "common/util.h"
+#include "common/system.h"
 
 DECLARE_SINGLETON(Common::ConfigManager);
 
-#ifdef __PLAYSTATION2__
-#include "backends/platform/ps2/systemps2.h"
-#endif
-
-#ifdef IPHONE
-#include "backends/platform/iphone/osys_iphone.h"
-#endif
-
-#if defined(UNIX)
-#ifdef MACOSX
-#define DEFAULT_CONFIG_FILE "Library/Preferences/ScummVM Preferences"
-#else
-#define DEFAULT_CONFIG_FILE ".scummvmrc"
-#endif
-#else
-#define DEFAULT_CONFIG_FILE "scummvm.ini"
-#endif
-
 #define MAXLINELEN 256
 
 static bool isValidDomainName(const Common::String &domName) {
@@ -85,77 +68,22 @@ ConfigManager::ConfigManager()
 
 
 void ConfigManager::loadDefaultConfigFile() {
-	char configFile[MAXPATHLEN];
-	// GP2X is Linux based but Home dir can be read only so do not use it and put the config in the executable dir.
-	// On the iPhone, the home dir of the user when you launch the app from the Springboard, is /. Which we don't want.
-#if defined(UNIX) && !defined(GP2X) && !defined(IPHONE)
-	const char *home = getenv("HOME");
-	if (home != NULL && strlen(home) < MAXPATHLEN)
-		snprintf(configFile, MAXPATHLEN, "%s/%s", home, DEFAULT_CONFIG_FILE);
-	else
-		strcpy(configFile, DEFAULT_CONFIG_FILE);
-#else
-	#if defined (WIN32) && !defined(_WIN32_WCE) && !defined(__SYMBIAN32__)
-		OSVERSIONINFO win32OsVersion;
-		ZeroMemory(&win32OsVersion, sizeof(OSVERSIONINFO));
-		win32OsVersion.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
-		GetVersionEx(&win32OsVersion);
-		// Check for non-9X version of Windows.
-		if (win32OsVersion.dwPlatformId != VER_PLATFORM_WIN32_WINDOWS) {
-			// Use the Application Data directory of the user profile.
-			if (win32OsVersion.dwMajorVersion >= 5) {
-				if (!GetEnvironmentVariable("APPDATA", configFile, sizeof(configFile)))
-					error("Unable to access application data directory");
-			} else {
-				if (!GetEnvironmentVariable("USERPROFILE", configFile, sizeof(configFile)))
-					error("Unable to access user profile directory");
-
-				strcat(configFile, "\\Application Data");
-				CreateDirectory(configFile, NULL);
-			}
+	_appDomain.clear();
+	_gameDomains.clear();
+	_transientDomain.clear();
+	_domainSaveOrder.clear();
 
-			strcat(configFile, "\\ScummVM");
-			CreateDirectory(configFile, NULL);
-			strcat(configFile, "\\" DEFAULT_CONFIG_FILE);
-
-			if (fopen(configFile, "r") == NULL) {
-				// Check windows directory
-				char oldConfigFile[MAXPATHLEN];
-				GetWindowsDirectory(oldConfigFile, MAXPATHLEN);
-				strcat(oldConfigFile, "\\" DEFAULT_CONFIG_FILE);
-				if (fopen(oldConfigFile, "r")) {
-					printf("The default location of the config file (scummvm.ini) in ScummVM has changed,\n");
-					printf("under Windows NT4/2000/XP/Vista. You may want to consider moving your config\n");
-					printf("file from the old default location:\n");
-					printf("%s\n", oldConfigFile);
-					printf("to the new default location:\n");
-					printf("%s\n\n", configFile);
-					strcpy(configFile, oldConfigFile);
-				}
-			}
-		} else {
-			// Check windows directory
-			GetWindowsDirectory(configFile, MAXPATHLEN);
-			strcat(configFile, "\\" DEFAULT_CONFIG_FILE);
-		}
+	// Open the default config file
+	SeekableReadStream *stream = g_system->openConfigFileForReading();
+	_filename.clear();	// clear the filename to indicate that we are using the default config file
 
-	#elif defined(PALMOS_MODE)
-		strcpy(configFile,"/PALM/Programs/ScummVM/" DEFAULT_CONFIG_FILE);
-	#elif defined(IPHONE)
-		strcpy(configFile, OSystem_IPHONE::getConfigPath());	
-	#elif defined(__PLAYSTATION2__)
-		((OSystem_PS2*)g_system)->makeConfigPath(configFile);
-	#elif defined(__PSP__)
-		strcpy(configFile, "ms0:/" DEFAULT_CONFIG_FILE);
-	#elif defined (__SYMBIAN32__)
-		strcpy(configFile, Symbian::GetExecutablePath());
-		strcat(configFile, DEFAULT_CONFIG_FILE);
-	#else
-		strcpy(configFile, DEFAULT_CONFIG_FILE);
-	#endif
-#endif
+	// ... load it ...
+	assert(stream);
+	loadStream(*stream);
+	
+	// ... and close it again.
+	delete stream;
 
-	loadConfigFile(configFile);
 	flushToDisk();
 }
 
@@ -163,160 +91,168 @@ void ConfigManager::loadConfigFile(const String &filename) {
 	_appDomain.clear();
 	_gameDomains.clear();
 	_transientDomain.clear();
+	_domainSaveOrder.clear();
 
 	_filename = filename;
-	_domainSaveOrder.clear();
-	loadFile(_filename);
-	printf("Using configuration file: %s\n", _filename.c_str());
-}
 
-void ConfigManager::loadFile(const String &filename) {
 	File cfg_file;
-
 	if (!cfg_file.open(filename)) {
 		printf("Creating configuration file: %s\n", filename.c_str());
 	} else {
-		String domain;
-		String comment;
-		int lineno = 0;
-
-		// TODO: Detect if a domain occurs multiple times (or likewise, if
-		// a key occurs multiple times inside one domain).
-
-		while (!cfg_file.eof() && !cfg_file.ioFailed()) {
-			lineno++;
-
-			// Read a line
-			String line;
-			while (line.lastChar() != '\n') {
-				char buf[MAXLINELEN];
-				if (!cfg_file.readLine_NEW(buf, MAXLINELEN))
-					break;
-				line += buf;
+		printf("Using configuration file: %s\n", _filename.c_str());
+		loadStream(cfg_file);
+	}
+}
+
+void ConfigManager::loadStream(SeekableReadStream &stream) {
+
+	String domain;
+	String comment;
+	int lineno = 0;
+
+	// TODO: Detect if a domain occurs multiple times (or likewise, if
+	// a key occurs multiple times inside one domain).
+
+	while (!stream.eos() && !stream.ioFailed()) {
+		lineno++;
+
+		// Read a line
+		String line;
+		while (line.lastChar() != '\n') {
+			char buf[MAXLINELEN];
+			if (!stream.readLine_NEW(buf, MAXLINELEN))
+				break;
+			line += buf;
+		}
+
+		if (line.size() == 0) {
+			// Do nothing
+		} else if (line[0] == '#') {
+			// Accumulate comments here. Once we encounter either the start
+			// of a new domain, or a key-value-pair, we associate the value
+			// of the 'comment' variable with that entity.
+			comment += line;
+		} else if (line[0] == '[') {
+			// It's a new domain which begins here.
+			const char *p = line.c_str() + 1;
+			// Get the domain name, and check whether it's valid (that
+			// is, verify that it only consists of alphanumerics,
+			// dashes and underscores).
+			while (*p && (isalnum(*p) || *p == '-' || *p == '_'))
+				p++;
+
+			switch (*p) {
+			case '\0':
+				error("Config file buggy: missing ] in line %d", lineno);
+				break;
+			case ']':
+				domain = String(line.c_str() + 1, p - (line.c_str() + 1));
+				//domain = String(line.c_str() + 1, p);	// TODO: Pending Common::String changes
+				break;
+			default:
+				error("Config file buggy: Invalid character '%c' occured in domain name in line %d", *p, lineno);
 			}
 
-			if (line.size() == 0) {
-				// Do nothing
-			} else if (line[0] == '#') {
-				// Accumulate comments here. Once we encounter either the start
-				// of a new domain, or a key-value-pair, we associate the value
-				// of the 'comment' variable with that entity.
-				comment += line;
-			} else if (line[0] == '[') {
-				// It's a new domain which begins here.
-				const char *p = line.c_str() + 1;
-				// Get the domain name, and check whether it's valid (that
-				// is, verify that it only consists of alphanumerics,
-				// dashes and underscores).
-				while (*p && (isalnum(*p) || *p == '-' || *p == '_'))
-					p++;
-
-				switch (*p) {
-				case '\0':
-					error("Config file buggy: missing ] in line %d", lineno);
-					break;
-				case ']':
-					domain = String(line.c_str() + 1, p - (line.c_str() + 1));
-					//domain = String(line.c_str() + 1, p);	// TODO: Pending Common::String changes
-					break;
-				default:
-					error("Config file buggy: Invalid character '%c' occured in domain name in line %d", *p, lineno);
-				}
-
-				// Store domain comment
-				if (domain == kApplicationDomain) {
-					_appDomain.setDomainComment(comment);
-				} else {
-					_gameDomains[domain].setDomainComment(comment);
-				}
-				comment.clear();
-
-				_domainSaveOrder.push_back(domain);
+			// Store domain comment
+			if (domain == kApplicationDomain) {
+				_appDomain.setDomainComment(comment);
 			} else {
-				// This line should be a line with a 'key=value' pair, or an empty one.
-				
-				// Skip leading whitespaces
-				const char *t = line.c_str();
-				while (isspace(*t))
-					t++;
-
-				// Skip empty lines / lines with only whitespace
-				if (*t == 0)
-					continue;
-
-				// If no domain has been set, this config file is invalid!
-				if (domain.empty()) {
-					error("Config file buggy: Key/value pair found outside a domain in line %d", lineno);
-				}
-
-				// Split string at '=' into 'key' and 'value'. First, find the "=" delimeter.
-				const char *p = strchr(t, '=');
-				if (!p)
-					error("Config file buggy: Junk found in line line %d: '%s'", lineno, t);
-
-				// Trim spaces before the '=' to obtain the key
-				const char *p2 = p;
-				while (p2 > t && isspace(*(p2-1)))
-					p2--;
-				String key(t, p2 - t);
-				
-				// Skip spaces after the '='
-				t = p + 1;
-				while (isspace(*t))
-					t++;
-
-				// Trim trailing spaces
-				p2 = t + strlen(t);
-				while (p2 > t && isspace(*(p2-1)))
-					p2--;
-
-				String value(t, p2 - t);
-
-				// Finally, store the key/value pair in the active domain
-				set(key, value, domain);
-
-				// Store comment
-				if (domain == kApplicationDomain) {
-					_appDomain.setKVComment(key, comment);
-				} else {
-					_gameDomains[domain].setKVComment(key, comment);
-				}
-				comment.clear();
+				_gameDomains[domain].setDomainComment(comment);
+			}
+			comment.clear();
+
+			_domainSaveOrder.push_back(domain);
+		} else {
+			// This line should be a line with a 'key=value' pair, or an empty one.
+			
+			// Skip leading whitespaces
+			const char *t = line.c_str();
+			while (isspace(*t))
+				t++;
+
+			// Skip empty lines / lines with only whitespace
+			if (*t == 0)
+				continue;
+
+			// If no domain has been set, this config file is invalid!
+			if (domain.empty()) {
+				error("Config file buggy: Key/value pair found outside a domain in line %d", lineno);
 			}
+
+			// Split string at '=' into 'key' and 'value'. First, find the "=" delimeter.
+			const char *p = strchr(t, '=');
+			if (!p)
+				error("Config file buggy: Junk found in line line %d: '%s'", lineno, t);
+
+			// Extract the key/value pair
+			String key(t, p);
+			String value(p + 1);
+			
+			// Trim of spaces
+			key.trim();
+			value.trim();
+
+			// Finally, store the key/value pair in the active domain
+			set(key, value, domain);
+
+			// Store comment
+			if (domain == kApplicationDomain) {
+				_appDomain.setKVComment(key, comment);
+			} else {
+				_gameDomains[domain].setKVComment(key, comment);
+			}
+			comment.clear();
 		}
 	}
 }
 
 void ConfigManager::flushToDisk() {
 #ifndef __DC__
-	DumpFile cfg_file;
+	WriteStream *stream;
 
-	if (!cfg_file.open(_filename)) {
-		warning("Unable to write configuration file: %s", _filename.c_str());
+	if (_filename.empty()) {
+		// Write to the default config file
+		stream = g_system->openConfigFileForWriting();
+		if (!stream)	// If writing to the config file is not possible, do nothing
+			return;
 	} else {
-		// First write the domains in _domainSaveOrder, in that order.
-		// Note: It's possible for _domainSaveOrder to list domains which
-		// are not present anymore.
-		StringList::const_iterator i;
-		for (i = _domainSaveOrder.begin(); i != _domainSaveOrder.end(); ++i) {
-			if (kApplicationDomain == *i) {
-				writeDomain(cfg_file, *i, _appDomain);
-			} else if (_gameDomains.contains(*i)) {
-				writeDomain(cfg_file, *i, _gameDomains[*i]);
-			}
+		DumpFile *dump = new DumpFile();
+		assert(dump);
+
+		if (!dump->open(_filename)) {
+			warning("Unable to write configuration file: %s", _filename.c_str());
+			delete dump;
+			return;
+		}
+		
+		stream = dump;
+	}
+
+	// First write the domains in _domainSaveOrder, in that order.
+	// Note: It's possible for _domainSaveOrder to list domains which
+	// are not present anymore.
+	StringList::const_iterator i;
+	for (i = _domainSaveOrder.begin(); i != _domainSaveOrder.end(); ++i) {
+		if (kApplicationDomain == *i) {
+			writeDomain(*stream, *i, _appDomain);
+		} else if (_gameDomains.contains(*i)) {
+			writeDomain(*stream, *i, _gameDomains[*i]);
 		}
+	}
 
-		DomainMap::const_iterator d;
+	DomainMap::const_iterator d;
 
 
-		// Now write the domains which haven't been written yet
-		if (find(_domainSaveOrder.begin(), _domainSaveOrder.end(), kApplicationDomain) == _domainSaveOrder.end())
-			writeDomain(cfg_file, kApplicationDomain, _appDomain);
-		for (d = _gameDomains.begin(); d != _gameDomains.end(); ++d) {
-			if (find(_domainSaveOrder.begin(), _domainSaveOrder.end(), d->_key) == _domainSaveOrder.end())
-				writeDomain(cfg_file, d->_key, d->_value);
-		}
+	// Now write the domains which haven't been written yet
+	if (find(_domainSaveOrder.begin(), _domainSaveOrder.end(), kApplicationDomain) == _domainSaveOrder.end())
+		writeDomain(*stream, kApplicationDomain, _appDomain);
+	for (d = _gameDomains.begin(); d != _gameDomains.end(); ++d) {
+		if (find(_domainSaveOrder.begin(), _domainSaveOrder.end(), d->_key) == _domainSaveOrder.end())
+			writeDomain(*stream, d->_key, d->_value);
 	}
+
+	delete stream;
+
 #endif // !__DC__
 }
 
diff --git a/common/config-manager.h b/common/config-manager.h
index bebb59b539..0b1aa73fdb 100644
--- a/common/config-manager.h
+++ b/common/config-manager.h
@@ -36,7 +36,7 @@
 namespace Common {
 
 class WriteStream;
-
+class SeekableReadStream;
 
 /**
  * The (singleton) configuration manager, used to query & set configuration
@@ -156,7 +156,7 @@ private:
 	friend class Singleton<SingletonBaseType>;
 	ConfigManager();
 
-	void			loadFile(const String &filename);
+	void			loadStream(SeekableReadStream &stream);
 	void			writeDomain(WriteStream &stream, const String &name, const Domain &domain);
 
 	Domain			_transientDomain;
diff --git a/common/system.cpp b/common/system.cpp
index 8d528258f4..2dd0192aec 100644
--- a/common/system.cpp
+++ b/common/system.cpp
@@ -121,3 +121,132 @@ void OSystem::clearScreen() {
 	memset(screen->pixels, 0, screen->h * screen->pitch);
 	unlockScreen();
 }
+
+
+/*
+FIXME: The config file loading code below needs to be cleaned up.
+ Port specific variants should be pushed into the respective ports.
+
+ Ideally, the default OSystem::openConfigFileForReading/Writing methods
+ should be removed completely. 
+*/
+
+#include "common/file.h"
+
+#ifdef __PLAYSTATION2__
+#include "backends/platform/ps2/systemps2.h"
+#endif
+
+#ifdef IPHONE
+#include "backends/platform/iphone/osys_iphone.h"
+#endif
+
+
+#if defined(UNIX)
+#ifdef MACOSX
+#define DEFAULT_CONFIG_FILE "Library/Preferences/ScummVM Preferences"
+#else
+#define DEFAULT_CONFIG_FILE ".scummvmrc"
+#endif
+#else
+#define DEFAULT_CONFIG_FILE "scummvm.ini"
+#endif
+
+static Common::String getDefaultConfigFileName() {
+	char configFile[MAXPATHLEN];
+
+#if defined (WIN32) && !defined(_WIN32_WCE) && !defined(__SYMBIAN32__)
+	OSVERSIONINFO win32OsVersion;
+	ZeroMemory(&win32OsVersion, sizeof(OSVERSIONINFO));
+	win32OsVersion.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
+	GetVersionEx(&win32OsVersion);
+	// Check for non-9X version of Windows.
+	if (win32OsVersion.dwPlatformId != VER_PLATFORM_WIN32_WINDOWS) {
+		// Use the Application Data directory of the user profile.
+		if (win32OsVersion.dwMajorVersion >= 5) {
+			if (!GetEnvironmentVariable("APPDATA", configFile, sizeof(configFile)))
+				error("Unable to access application data directory");
+		} else {
+			if (!GetEnvironmentVariable("USERPROFILE", configFile, sizeof(configFile)))
+				error("Unable to access user profile directory");
+
+			strcat(configFile, "\\Application Data");
+			CreateDirectory(configFile, NULL);
+		}
+
+		strcat(configFile, "\\ScummVM");
+		CreateDirectory(configFile, NULL);
+		strcat(configFile, "\\" DEFAULT_CONFIG_FILE);
+
+		if (fopen(configFile, "r") == NULL) {
+			// Check windows directory
+			char oldConfigFile[MAXPATHLEN];
+			GetWindowsDirectory(oldConfigFile, MAXPATHLEN);
+			strcat(oldConfigFile, "\\" DEFAULT_CONFIG_FILE);
+			if (fopen(oldConfigFile, "r")) {
+				printf("The default location of the config file (scummvm.ini) in ScummVM has changed,\n");
+				printf("under Windows NT4/2000/XP/Vista. You may want to consider moving your config\n");
+				printf("file from the old default location:\n");
+				printf("%s\n", oldConfigFile);
+				printf("to the new default location:\n");
+				printf("%s\n\n", configFile);
+				strcpy(configFile, oldConfigFile);
+			}
+		}
+	} else {
+		// Check windows directory
+		GetWindowsDirectory(configFile, MAXPATHLEN);
+		strcat(configFile, "\\" DEFAULT_CONFIG_FILE);
+	}
+
+#elif defined(PALMOS_MODE)
+	strcpy(configFile,"/PALM/Programs/ScummVM/" DEFAULT_CONFIG_FILE);
+#elif defined(IPHONE)
+	strcpy(configFile, OSystem_IPHONE::getConfigPath());	
+#elif defined(__PLAYSTATION2__)
+	((OSystem_PS2*)g_system)->makeConfigPath(configFile);
+#elif defined(__PSP__)
+	strcpy(configFile, "ms0:/" DEFAULT_CONFIG_FILE);
+#elif defined (__SYMBIAN32__)
+	strcpy(configFile, Symbian::GetExecutablePath());
+	strcat(configFile, DEFAULT_CONFIG_FILE);
+#elif defined(UNIX) && !defined(GP2X) && !defined(IPHONE)
+	// On UNIX type systems, by default we store the config file inside
+	// to the HOME directory of the user.
+	//	
+	// GP2X is Linux based but Home dir can be read only so do not use
+	// it and put the config in the executable dir.
+	//
+	// On the iPhone, the home dir of the user when you launch the app
+	// from the Springboard, is /. Which we don't want.
+	const char *home = getenv("HOME");
+	if (home != NULL && strlen(home) < MAXPATHLEN)
+		snprintf(configFile, MAXPATHLEN, "%s/%s", home, DEFAULT_CONFIG_FILE);
+	else
+		strcpy(configFile, DEFAULT_CONFIG_FILE);
+
+#else
+	strcpy(configFile, DEFAULT_CONFIG_FILE);
+#endif
+
+
+	return configFile;
+}
+
+Common::SeekableReadStream *OSystem::openConfigFileForReading() {
+	Common::File *confFile = new Common::File();
+	assert(confFile);
+	confFile->open(getDefaultConfigFileName());
+	return confFile;
+}
+
+Common::WriteStream *OSystem::openConfigFileForWriting() {
+#ifdef __DC__
+	return 0;
+#else
+	Common::DumpFile *confFile = new Common::DumpFile();
+	assert(confFile);
+	confFile->open(getDefaultConfigFileName());
+	return confFile;
+#endif
+}
diff --git a/common/system.h b/common/system.h
index b895a5cfba..501d0802fd 100644
--- a/common/system.h
+++ b/common/system.h
@@ -44,6 +44,8 @@ namespace Common {
 	class EventManager;
 	class SaveFileManager;
 	class TimerManager;
+	class SeekableReadStream;
+	class WriteStream;
 }
 
 class FilesystemFactory;
@@ -900,10 +902,25 @@ public:
 	/**
 	 * Returns the FilesystemFactory object, depending on the current architecture.
 	 *
-	 * @return FilesystemFactory* The specific factory for the current architecture.
+	 * @return the FSNode factory for the current architecture
 	 */
 	virtual FilesystemFactory *getFilesystemFactory() = 0;
 
+	/**
+	 * Open the default config file for reading, by returning a suitable
+	 * ReadStream instance. It is the callers responsiblity to delete
+	 * the stream after use.
+	 */
+	virtual Common::SeekableReadStream *openConfigFileForReading();
+
+	/**
+	 * Open the default config file for writing, by returning a suitable
+	 * WriteStream instance. It is the callers responsiblity to delete
+	 * the stream after use.
+	 *
+	 * May return 0 to indicate that writing to config file is not possible.
+	 */
+	virtual Common::WriteStream *openConfigFileForWriting();
 
 	/**
 	 * Return String which is used for backend-specific addition to theme