[deb_libnfs.git] / include / libnfs.h

/*
   Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published by
   the Free Software Foundation; either version 2.1 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
/*
 * This is the highlevel interface to access NFS resources using a posix-like interface
 */
#include <stdint.h>

struct nfs_context;
struct rpc_context;

/*
 * Used for interfacing the async version of the api into an external eventsystem
 */
int nfs_get_fd(struct nfs_context *nfs);
int nfs_which_events(struct nfs_context *nfs);
int nfs_service(struct nfs_context *nfs, int revents);

/*
 * Used if you need different credentials than the default for the current user.
 */
struct AUTH;
void nfs_set_auth(struct nfs_context *nfs, struct AUTH *auth);


/*
 * When an operation failed, this function can extract a detailed error string.
 */
char *nfs_get_error(struct nfs_context *nfs);


/*
 * Callback for all ASYNC nfs functions
 */
typedef void (*nfs_cb)(int err, struct nfs_context *nfs, void *data, void *private_data);

/*
 * Callback for all ASYNC rpc functions
 */
typedef void (*rpc_cb)(struct rpc_context *rpc, int status, void *data, void *private_data);


/*
 * NFS CONTEXT.
 */
/*
 * Create an NFS c, the context.
 * Function returns
 *  NULL : Failed to create a context.
 *  *nfs : A pointer to an nfs context.
 */
struct nfs_context *nfs_init_context(void);
/*
 * Destroy an nfs context.
 */
void nfs_destroy_context(struct nfs_context *nfs);


struct nfsfh;

/*
 * Get the maximum supported READ3 size by the server
 */
size_t nfs_get_readmax(struct nfs_context *nfs);

/*
 * Get the maximum supported WRITE3 size by the server
 */
size_t nfs_get_writemax(struct nfs_context *nfs);


/*
 * MOUNT THE EXPORT
 */
/*
 * Async nfs mount.
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_mount_async(struct nfs_context *nfs, const char *server, const char *exportname, nfs_cb cb, void *private_data);
/*
 * Sync nfs mount.
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_mount(struct nfs_context *nfs, const char *server, const char *exportname);


/*
 * STAT()
 */
/*
 * Async stat(<filename>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is struct stat *
 * -errno : An error occured.
 *          data is the error string.
 */
struct stat;
int nfs_stat_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync stat(<filename>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_stat(struct nfs_context *nfs, const char *path, struct stat *st);


/*
 * FSTAT()
 */
/*
 * Async fstat(nfsfh *)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is struct stat *
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_fstat_async(struct nfs_context *nfs, struct nfsfh *nfsfh, nfs_cb cb, void *private_data);
/*
 * Sync fstat(nfsfh *)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_fstat(struct nfs_context *nfs, struct nfsfh *nfsfh, struct stat *st);


/*
 * OPEN()
 */
/*
 * Async open(<filename>)
 *
 * mode is a combination of the flags : O_RDOLNY, O_WRONLY, O_RDWR , O_SYNC
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is a struct *nfsfh;
 *          The nfsfh is close using nfs_close().
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_open_async(struct nfs_context *nfs, const char *path, int mode, nfs_cb cb, void *private_data);
/*
 * Sync stat(<filename>)
 * Function returns
 *      0 : The operation was successfull. *nfsfh is filled in.
 * -errno : The command failed.
 */
int nfs_open(struct nfs_context *nfs, const char *path, int mode, struct nfsfh **nfsfh);


/*
 * CLOSE
 */
/*
 * Async close(nfsfh)
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_close_async(struct nfs_context *nfs, struct nfsfh *nfsfh, nfs_cb cb, void *private_data);
/*
 * Sync close(nfsfh)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_close(struct nfs_context *nfs, struct nfsfh *nfsfh);


/*
 * PREAD()
 */
/*
 * Async pread()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *    >=0 : Success.
 *          status is numer of bytes read.
 *          data is a pointer to the returned data.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_pread_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, size_t count, nfs_cb cb, void *private_data);
/*
 * Sync pread()
 * Function returns
 *    >=0 : numer of bytes read.
 * -errno : An error occured.
 */
int nfs_pread(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, size_t count, char *buf);


/*
 * READ()
 */
/*
 * Async read()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *    >=0 : Success.
 *          status is numer of bytes read.
 *          data is a pointer to the returned data.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_read_async(struct nfs_context *nfs, struct nfsfh *nfsfh, size_t count, nfs_cb cb, void *private_data);
/*
 * Sync read()
 * Function returns
 *    >=0 : numer of bytes read.
 * -errno : An error occured.
 */
int nfs_read(struct nfs_context *nfs, struct nfsfh *nfsfh, size_t count, char *buf);


/*
 * PWRITE()
 */
/*
 * Async pwrite()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *    >=0 : Success.
 *          status is numer of bytes written.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_pwrite_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, size_t count, char *buf, nfs_cb cb, void *private_data);
/*
 * Sync pwrite()
 * Function returns
 *    >=0 : numer of bytes written.
 * -errno : An error occured.
 */
int nfs_pwrite(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, size_t count, char *buf);


/*
 * WRITE()
 */
/*
 * Async write()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *    >=0 : Success.
 *          status is numer of bytes written.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_write_async(struct nfs_context *nfs, struct nfsfh *nfsfh, size_t count, char *buf, nfs_cb cb, void *private_data);
/*
 * Sync write()
 * Function returns
 *    >=0 : numer of bytes written.
 * -errno : An error occured.
 */
int nfs_write(struct nfs_context *nfs, struct nfsfh *nfsfh, size_t count, char *buf);


/*
 * LSEEK()
 */
/*
 * Async lseek()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *    >=0 : Success.
 *          data is off_t * for the current position.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_lseek_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, int whence, nfs_cb cb, void *private_data);
/*
 * Sync lseek()
 * Function returns
 *    >=0 : numer of bytes read.
 * -errno : An error occured.
 */
int nfs_lseek(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t offset, int whence, off_t *current_offset);


/*
 * FSYNC()
 */
/*
 * Async fsync()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_fsync_async(struct nfs_context *nfs, struct nfsfh *nfsfh, nfs_cb cb, void *private_data);
/*
 * Sync fsync()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_fsync(struct nfs_context *nfs, struct nfsfh *nfsfh);


/*
 * TRUNCATE()
 */
/*
 * Async truncate()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_truncate_async(struct nfs_context *nfs, const char *path, off_t length, nfs_cb cb, void *private_data);
/*
 * Sync truncate()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_truncate(struct nfs_context *nfs, const char *path, off_t length);


/*
 * FTRUNCATE()
 */
/*
 * Async ftruncate()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_ftruncate_async(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t length, nfs_cb cb, void *private_data);
/*
 * Sync ftruncate()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_ftruncate(struct nfs_context *nfs, struct nfsfh *nfsfh, off_t length);


/*
 * MKDIR()
 */
/*
 * Async mkdir()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_mkdir_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync mkdir()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_mkdir(struct nfs_context *nfs, const char *path);


/*
 * RMDIR()
 */
/*
 * Async rmdir()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_rmdir_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync rmdir()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_rmdir(struct nfs_context *nfs, const char *path);


/*
 * CREAT()
 */
/*
 * Async creat()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is a struct *nfsfh;
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_creat_async(struct nfs_context *nfs, const char *path, int mode, nfs_cb cb, void *private_data);
/*
 * Sync creat()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_creat(struct nfs_context *nfs, const char *path, int mode, struct nfsfh **nfsfh);


/*
 * UNLINK()
 */
/*
 * Async unlink()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_unlink_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync unlink()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_unlink(struct nfs_context *nfs, const char *path);


/*
 * OPENDIR()
 */
struct nfsdir;
/*
 * Async opendir()
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When struct nfsdir * is returned, this resource is closed/freed by calling nfs_closedir()
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is struct nfsdir *
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_opendir_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync opendir()
 * Function returns
 *      0 : Success
 * -errno : An error occured.
 */
int nfs_opendir(struct nfs_context *nfs, const char *path, struct nfsdir **nfsdir);


/*
 * READDIR()
 */
struct nfsdirent  {
       struct nfsdirent *next;
       char *name;
       uint64_t inode;

       /* some extra fields we get for free through the READDIRPLUS3 call. You need libnfs-raw-nfs.h for these */
       uint32_t type; /* NF3REG, NF3DIR, NF3BLK, ... */
       uint32_t mode;
       uint64_t size;
       struct timeval atime;
       struct timeval mtime;
       struct timeval ctime;
};
/*
 * nfs_readdir() never blocks, so no special sync/async versions are available
 */
struct nfsdirent *nfs_readdir(struct nfs_context *nfs, struct nfsdir *nfsdir);


/*
 * READDIR()
 */
/*
 * nfs_closedir() never blocks, so no special sync/async versions are available
 */
void nfs_closedir(struct nfs_context *nfs, struct nfsdir *nfsdir);


/*
 * STATVFS()
 */
/*
 * Async statvfs(<dirname>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is struct statvfs *
 * -errno : An error occured.
 *          data is the error string.
 */
struct statvfs;
int nfs_statvfs_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync statvfs(<dirname>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_statvfs(struct nfs_context *nfs, const char *path, struct statvfs *svfs);


/*
 * READLINK()
 */
/*
 * Async readlink(<name>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is a char *
 *          data is only valid during the callback and is automatically freed when the callback returns.
 * -errno : An error occured.
 *          data is the error string.
 */
struct statvfs;
int nfs_readlink_async(struct nfs_context *nfs, const char *path, nfs_cb cb, void *private_data);
/*
 * Sync readlink(<name>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_readlink(struct nfs_context *nfs, const char *path, char *buf, int bufsize);


/*
 * CHMOD()
 */
/*
 * Async chmod(<name>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_chmod_async(struct nfs_context *nfs, const char *path, int mode, nfs_cb cb, void *private_data);
/*
 * Sync chmod(<name>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_chmod(struct nfs_context *nfs, const char *path, int mode);


/*
 * FCHMOD()
 */
/*
 * Async fchmod(<handle>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_fchmod_async(struct nfs_context *nfs, struct nfsfh *nfsfh, int mode, nfs_cb cb, void *private_data);
/*
 * Sync fchmod(<handle>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_fchmod(struct nfs_context *nfs, struct nfsfh *nfsfh, int mode);


/*
 * CHOWN()
 */
/*
 * Async chown(<name>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_chown_async(struct nfs_context *nfs, const char *path, int uid, int gid, nfs_cb cb, void *private_data);
/*
 * Sync chown(<name>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_chown(struct nfs_context *nfs, const char *path, int uid, int gid);


/*
 * FCHOWN()
 */
/*
 * Async fchown(<handle>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_fchown_async(struct nfs_context *nfs, struct nfsfh *nfsfh, int uid, int gid, nfs_cb cb, void *private_data);
/*
 * Sync fchown(<handle>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_fchown(struct nfs_context *nfs, struct nfsfh *nfsfh, int uid, int gid);


/*
 * UTIMES()
 */
/*
 * Async utimes(<path>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_utimes_async(struct nfs_context *nfs, const char *path, struct timeval *times, nfs_cb cb, void *private_data);
/*
 * Sync utimes(<path>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_utimes(struct nfs_context *nfs, const char *path, struct timeval *times);


/*
 * UTIME()
 */
/*
 * Async utime(<path>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
struct utimbuf;
int nfs_utime_async(struct nfs_context *nfs, const char *path, struct utimbuf *times, nfs_cb cb, void *private_data);
/*
 * Sync utime(<path>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_utime(struct nfs_context *nfs, const char *path, struct utimbuf *times);


/*
 * ACCESS()
 */
/*
 * Async access(<path>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_access_async(struct nfs_context *nfs, const char *path, int mode, nfs_cb cb, void *private_data);
/*
 * Sync access(<path>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_access(struct nfs_context *nfs, const char *path, int mode);


/*
 * SYMLINK()
 */
/*
 * Async symlink(<path>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_symlink_async(struct nfs_context *nfs, const char *oldpath, const char *newpath, nfs_cb cb, void *private_data);
/*
 * Sync symlink(<path>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_symlink(struct nfs_context *nfs, const char *oldpath, const char *newpath);


/*
 * RENAME()
 */
/*
 * Async rename(<oldpath>, <newpath>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_rename_async(struct nfs_context *nfs, const char *oldpath, const char *newpath, nfs_cb cb, void *private_data);
/*
 * Sync rename(<oldpath>, <newpath>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_rename(struct nfs_context *nfs, const char *oldpath, const char *newpath);


/*
 * LINK()
 */
/*
 * Async link(<oldpath>, <newpath>)
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is NULL
 * -errno : An error occured.
 *          data is the error string.
 */
int nfs_link_async(struct nfs_context *nfs, const char *oldpath, const char *newpath, nfs_cb cb, void *private_data);
/*
 * Sync link(<oldpath>, <newpath>)
 * Function returns
 *      0 : The operation was successfull.
 * -errno : The command failed.
 */
int nfs_link(struct nfs_context *nfs, const char *oldpath, const char *newpath);


/*
 * GETEXPORTS()
 */
/*
 * Async getexports()
 * NOTE: You must include 'libnfs-raw-mount.h' to get the definitions of the
 * returned structures.
 *
 * This function will return the list of exports from an NFS server.
 *
 * Function returns
 *  0 : The operation was initiated. Once the operation finishes, the callback will be invoked.
 * <0 : An error occured when trying to set up the operation. The callback will not be invoked.
 *
 * When the callback is invoked, status indicates the result:
 *      0 : Success.
 *          data is a pointer to an exports pointer:
 *          exports export = *(exports *)data;
 * -errno : An error occured.
 *          data is the error string.
 */
int mount_getexports_async(struct rpc_context *rpc, const char *server, rpc_cb cb, void *private_data);
/*
 * Sync getexports(<server>)
 * Function returns
 *            NULL : something failed
 *  exports export : a linked list of exported directories
 * 
 * returned data must be freed by calling mount_free_export_list(exportnode);
 */
struct exportnode *mount_getexports(const char *server);

void mount_free_export_list(struct exportnode *exports);


//qqq replace later with lseek(cur, 0)
off_t nfs_get_current_offset(struct nfsfh *nfsfh);


struct nfs_server_list {
       struct nfs_server_list *next;
       char *addr;
};

/*
 * Sync find_local_servers(<server>)
 * This function will probe all local networks for NFS server. This function will
 * block for one second while awaiting for all nfs servers to respond.
 *
 * Function returns
 * NULL : something failed
 *
 * struct nfs_server_list : a linked list of all discovered servers
 * 
 * returned data must be freed by nfs_free_srvr_list(srv);
 */
struct nfs_server_list *nfs_find_local_servers(void);
void free_nfs_srvr_list(struct nfs_server_list *srv);