/* * Copyright (c) 2007 Apple Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ #ifndef CONFIGURATION_H #define CONFIGURATION_H #include <sys/types.h> #include <cstdio> #include <stdexcept> // Strings to use when throwing configuration errors. These strings should // be in servermgr_comman/constants.h, but we are not ready for that yet. #define UNABLE_TO_OPEN_FILE_ERR "UNABLE_TO_OPEN_FILE_ERR" #define UNKNOWN_ERR "UNKNOWN_ERR" class ConfigurationFile { public: ConfigurationFile( const char *fileName ) throw( std::bad_alloc, std::runtime_error ); virtual ~ConfigurationFile() throw() ; /* Call this function to start writing a configuration file. Must be matched by a call to StopWrite(). Returns a FILE* to write to, NULL if there is an error. This call is not really thread safe, that is each configuration file should have at most one thread writing to it at a time. We could add locking to enforce this constraint, but the work and overhead is not justified at the present. */ virtual std::FILE *StartWrite(); /* Return true if the old configuration file was replaced by the new file, otherwise return false. */ virtual bool StopWrite(); /* Returns a FILE* for the configuration file. Do not close this file. Use this to read a file. */ virtual std::FILE *GetFileForReading() throw(); protected: /* Attempts to copy the contents of backupFileName to a new, nonexistant file in newFileName while ensuring it has exclusive file locks on the file. Returns true if the restore completed sucessfully, false otherwise */ virtual std::FILE *AttemptRestore( const char *newFileName, const char *backupFileName ); /* Cleanup the memory. This function helps make cleaning up memory in the constructor cleaner. */ virtual void CleanupMemory() throw(); protected: int fd; // file descriptor for the config file std::FILE *file; // FILE* for the config file std::FILE *tmpFile; // FILE* for temporary config file that // StartWrite() gives out const char *kFileName; // name of the configuration file char *backupFileName; // name of the backup configuration file char *defaultFileName; // name of the default configuration file char *tmpFileName; // name of the temporary file used when writing // out the configuration file mode_t permissions; // default file permissions for the config file protected: static const char *kBackupSuffix; // suffix for backup files static const char *kDefaultSuffix; // suffix for default files static const char *kTmpSuffix; // suffix for temporary files }; #endif // CONFIGURATION_H