lseek() finalized, added get_metadentry rpc, stat error handling

// To enabled logging for daemon

#define LOG_INFO

//#define LOG_DEBUG

//#define LOG_TRACE

#define LOG_TRACE

#define LOG_DAEMON_PATH "/tmp/adafs_daemon.log"

// Enable logging for preload

#define LOG_PRELOAD_INFO

//#define LOG_PRELOAD_DEBUG

//#define LOG_PRELOAD_TRACE

#define LOG_PRELOAD_TRACE

#define LOG_PRELOAD_PATH "/tmp/adafs_preload.log"

// Set a hostname suffix when a connection is built. E.g., "-ib" to use Infiniband

int remove_node(const std::string& path);

int get_metadentry_size(const std::string& path, size_t& ret_size);

int update_metadentry_size(const std::string& path, size_t io_size, off_t offset, bool append, size_t& read_size);

int update_metadentry(const std::string& path, Metadata& md);

    constexpr auto stat = "rpc_srv_stat";

    constexpr auto remove = "rpc_srv_rm_node";

    constexpr auto update_metadentry = "rpc_srv_update_metadentry";

    constexpr auto get_metadentry_size = "rpc_srv_get_metadentry_size";

    constexpr auto update_metadentry_size = "rpc_srv_update_metadentry_size";

    constexpr auto write_data = "rpc_srv_write_data";

    constexpr auto read_data = "rpc_srv_read_data";

int adafs_stat64(const std::string& path, struct stat64* buf);

off_t adafs_lseek(int fd, off_t offset, int whence);

ssize_t adafs_pread_ws(int fd, void* buf, size_t count, off_t offset);

ssize_t adafs_pwrite_ws(int fd, const void* buf, size_t count, off_t offset);

    bool append_flag_;

    int fd_;

    // XXX add mutex for pos. If dup is used excessively pos_ may be updated concurrently. The mutex is implemented in pos setter

    off_t pos_;

    FILE* tmp_file_;

    /*

XXX

shared:

- path

- flags

- pos

unique:

- sys fd (throw out. is already part as the key in the filemap)

- tmp_file

- int fd points to same shared ptr in file map

- fd attribute is not used -> throw out

- put tmp_file into another map<int(fd), FILE*>

- Add mutex for pos_

- Let's also properly add all flags from open in there into an enum or similar

     */

public:

    OpenFile(const std::string& path, bool append_flag);