require Exporter;
require DynaLoader;
use AutoLoader;
-use Data::Dumper;
our @ISA = qw(Exporter DynaLoader);
# Items to export into callers namespace by default. Note: do not export
# If you do not need this, moving things directly into @EXPORT or @EXPORT_OK
# will save memory.
our %EXPORT_TAGS = (
- 'all' => [ qw(XATTR_CREATE XATTR_REPLACE fuse_get_context fuse_version) ],
- 'xattr' => [ qw(XATTR_CREATE XATTR_REPLACE) ]
+ 'all' => [ qw(XATTR_CREATE XATTR_REPLACE fuse_get_context fuse_version FUSE_IOCTL_COMPAT FUSE_IOCTL_UNRESTRICTED FUSE_IOCTL_RETRY FUSE_IOCTL_MAX_IOV notify_poll pollhandle_destroy) ],
+ 'xattr' => [ qw(XATTR_CREATE XATTR_REPLACE) ],
+ 'ioctl' => [ qw(FUSE_IOCTL_COMPAT FUSE_IOCTL_UNRESTRICTED FUSE_IOCTL_RETRY FUSE_IOCTL_MAX_IOV) ],
);
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
our @EXPORT = ();
-our $VERSION = '0.11';
+our $VERSION = '0.15';
sub AUTOLOAD {
# This AUTOLOAD is used to 'autoload' constants from the constant()
goto &$AUTOLOAD;
}
-sub XATTR_CREATE {
- # See <sys/xattr.h>.
- return 1;
-}
-
-sub XATTR_REPLACE {
- # See <sys/xattr.h>.
- return 2;
-}
-
bootstrap Fuse $VERSION;
+use constant FUSE_IOCTL_COMPAT => (1 << 0);
+use constant FUSE_IOCTL_UNRESTRICTED => (1 << 1);
+use constant FUSE_IOCTL_RETRY => (1 << 2);
+use constant FUSE_IOCTL_MAX_IOV => 256;
+
sub main {
my @names = qw(getattr readlink getdir mknod mkdir unlink rmdir symlink
rename link chmod chown truncate utime open read write statfs
- flush release fsync setxattr getxattr listxattr removexattr opendir readdir releasedir fsyncdir);
+ flush release fsync setxattr getxattr listxattr removexattr
+ opendir readdir releasedir fsyncdir init destroy access
+ create ftruncate fgetattr lock utimens bmap);
+ my $fuse_version = fuse_version();
+ if ($fuse_version >= 2.8) {
+ # junk doesn't contain a function pointer, and hopefully
+ # never will; it's a "dead" zone in the struct
+ # fuse_operations where a flag bit is declared. we don't
+ # need to concern ourselves with it, and it appears any
+ # arch with a 64 bit pointer will align everything to
+ # 8 bytes, making the question of pointer alignment for
+ # the last 2 wrapper functions no big thing.
+ push(@names, qw/junk ioctl poll/);
+ }
my @subs = map {undef} @names;
my $tmp = 0;
my %mapping = map { $_ => $tmp++ } @names;
- my @otherargs = qw(debug threaded mountpoint mountopts);
- my %otherargs = (debug=>0, threaded=>0, mountpoint=>"", mountopts=>"");
+ my @otherargs = qw(debug threaded mountpoint mountopts nullpath_ok utimens_as_array);
+ my %otherargs = (
+ debug => 0,
+ threaded => 0,
+ mountpoint => "",
+ mountopts => "",
+ nullpath_ok => 0,
+ utimens_as_array => 0,
+ );
while(my $name = shift) {
my ($subref) = shift;
if(exists($otherargs{$name})) {
functions, as described in section 'FUNCTIONS YOUR FILESYSTEM MAY IMPLEMENT'.
A few special keys also exist:
-
-debug => boolean
-
=over 1
-This turns FUSE call tracing on and off. Default is 0 (which means off).
-
-=back
+=item debug => boolean
-mountpoint => string
+This turns FUSE call tracing on and off. Default is 0 (which means off).
-=over 1
+=item mountpoint => string
The point at which to mount this filesystem. There is no default, you must
specify this. An example would be '/mnt'.
-=back
-
-mountopts => string
+=item mountopts => string
-=over 1
-
-This is a comma seperated list of mount options to pass to the FUSE kernel
+This is a comma separated list of mount options to pass to the FUSE kernel
module.
At present, it allows the specification of the allow_other
mountopts => "allow_other" or
mountopts => ""
-=back
-
-threaded => boolean
-
-=over 1
+=item threaded => boolean
This turns FUSE multithreading on and off. The default is 0, meaning your FUSE
script will run in single-threaded mode. Note that single-threaded mode also
built with USE_ITHREADS, or if you have failed to use threads or
threads::shared.)
+=item nullpath_ok => boolean
+
+This flag tells Fuse to not pass paths for functions that operate on file
+or directory handles. This will yield empty path parameters for functions
+including read, write, flush, release, fsync, readdir, releasedir,
+fsyncdir, truncate, fgetattr and lock. If you use this, you must return
+file/directory handles from open, opendir and create. Default is 0 (off).
+Only effective on Fuse 2.8 and up; with earlier versions, this does nothing.
+
+=item utimens_as_array => boolean
+
+This flag causes timestamps passed via the utimens() call to be passed
+as arrays containing the time in seconds, and a second value containing
+the number of nanoseconds, instead of a floating point value. This allows
+for more precise times, as the normal floating point type used by Perl
+(double) loses accuracy starting at about tenths of a microsecond.
+
=back
=head3 Fuse::fuse_get_context
of the Fuse API in use at build time. Returned as a decimal value; i.e.,
for Fuse API v2.6, will return "2.6".
+=head3 Fuse::notify_poll
+
+Only available if the Fuse module is built against libfuse 2.8 or later.
+Use fuse_version() to determine if this is the case. Calling this function
+with a pollhandle argument (as provided to the C<poll> operation
+implementation) will send a notification to the caller poll()ing for
+I/O operation availability. If more than one pollhandle is provided for
+the same filehandle, only use the latest; you *can* send notifications
+to them all, but it is unnecessary and decreases performance.
+
+ONLY supply poll handles fed to you through C<poll> to this function.
+Due to thread safety requirements, we can't currently package the pointer
+up in an object the way we'd like to to prevent this situation, but your
+filesystem server program may segfault, or worse, if you feed things to
+this function which it is not supposed to receive. If you do anyway, we
+take no responsibility for whatever Bad Things(tm) may happen.
+
+=head3 Fuse::pollhandle_destroy
+
+Only available if the Fuse module is built against libfuse 2.8 or later.
+Use fuse_version() to determine if this is the case. This function destroys
+a poll handle (fed to your program through C<poll>). When you are done
+with a poll handle, either because it has been replaced, or because a
+notification has been sent to it, pass it to this function to dispose of
+it safely.
+
+ONLY supply poll handles fed to you through C<poll> to this function.
+Due to thread safety requirements, we can't currently package the pointer
+up in an object the way we'd like to to prevent this situation, but your
+filesystem server program may segfault, or worse, if you feed things to
+this function which it is not supposed to receive. If you do anyway, we
+take no responsibility for whatever Bad Things(tm) may happen.
+
=head2 FUNCTIONS YOUR FILESYSTEM MAY IMPLEMENT
=head3 getattr
Arguments: filename.
+
Returns a list, very similar to the 'stat' function (see
perlfunc). On error, simply return a single numeric scalar
value (e.g. "return -ENOENT();").
(The epoch was at 00:00 January 1, 1970 GMT.)
+If you wish to provide sub-second precision timestamps, they may be
+passed either as the fractional part of a floating-point value, or as a
+two-element array, passed as an array ref, with the first element
+containing the number of seconds since the epoch, and the second
+containing the number of nanoseconds. This provides complete time
+precision, as a floating point number starts losing precision at about
+a tenth of a microsecond. So if you really care about that sort of thing...
+
=head3 readlink
Arguments: link pathname.
+
Returns a scalar: either a numeric constant, or a text string.
This is called when dereferencing symbolic links, to learn the target.
=head3 getdir
Arguments: Containing directory name.
+
Returns a list: 0 or more text strings (the filenames), followed by a numeric errno (usually 0).
This is used to obtain directory listings. It's opendir(), readdir(), filldir() and closedir() all in one call.
example rv: return ('.', 'a', 'b', 0);
-=head3 readdir
-
-Arguments: Directory name, offset
-Returns: filename, offset to the next dirent, numeric errno 0 or -ENOENT()
-
=head3 mknod
Arguments: Filename, numeric modes, numeric device
+
Returns an errno (0 upon success, as usual).
This function is called for all non-directory, non-symlink nodes,
=head3 mkdir
Arguments: New directory pathname, numeric modes.
+
Returns an errno.
Called to create a directory.
=head3 unlink
Arguments: Filename.
+
Returns an errno.
Called to remove a file, device, or symlink.
=head3 rmdir
Arguments: Pathname.
+
Returns an errno.
Called to remove a directory.
=head3 symlink
Arguments: Existing filename, symlink name.
+
Returns an errno.
Called to create a symbolic link.
=head3 rename
Arguments: old filename, new filename.
+
Returns an errno.
Called to rename a file, and/or move a file from one directory to another.
=head3 link
Arguments: Existing filename, hardlink name.
+
Returns an errno.
Called to create hard links.
=head3 chmod
Arguments: Pathname, numeric modes.
+
Returns an errno.
Called to change permissions on a file/directory/device/symlink.
=head3 chown
Arguments: Pathname, numeric uid, numeric gid.
+
Returns an errno.
Called to change ownership of a file/directory/device/symlink.
=head3 truncate
Arguments: Pathname, numeric offset.
+
Returns an errno.
Called to truncate a file, at the given offset.
=head3 utime
Arguments: Pathname, numeric actime, numeric modtime.
+
Returns an errno.
Called to change access/modification times for a file/directory/device/symlink.
Arguments: Pathname, numeric flags (which is an OR-ing of stuff like O_RDONLY
and O_SYNC, constants you can import from POSIX), fileinfo hash reference.
+
Returns an errno, a file handle (optional).
-No creation, or trunctation flags (O_CREAT, O_EXCL, O_TRUNC) will be passed to open().
+No creation, or truncation flags (O_CREAT, O_EXCL, O_TRUNC) will be passed to open().
The fileinfo hash reference contains flags from the Fuse open call which may be modified by the module. The only fields presently supported are:
direct_io (version 2.4 onwards)
keep_cache (version 2.4 onwards)
- nonseekable (version 2.9 onwards)
+ nonseekable (version 2.8 onwards)
Your open() method needs only check if the operation is permitted for the given flags, and return 0 for success.
Optionally a file handle may be returned, which will be passed to subsequent read, write, flush, fsync and release calls.
=head3 read
Arguments: Pathname, numeric requested size, numeric offset, file handle
+
Returns a numeric errno, or a string scalar with up to $requestedsize bytes of data.
Called in an attempt to fetch a portion of the file.
=head3 statfs
Arguments: none
+
Returns any of the following:
-ENOANO()
=head3 flush
Arguments: Pathname, file handle
+
Returns an errno or 0 on success.
Called to synchronise any cached data. This is called before the file
=head3 release
Arguments: Pathname, numeric flags passed to open, file handle
+
Returns an errno or 0 on success.
Called to indicate that there are no more references to the file. Called once
=head3 fsync
Arguments: Pathname, numeric flags
+
Returns an errno or 0 on success.
Called to synchronise the file's contents. If flags is non-zero,
=head3 setxattr
Arguments: Pathname, extended attribute's name, extended attribute's value, numeric flags (which is an OR-ing of XATTR_CREATE and XATTR_REPLACE
+
Returns an errno or 0 on success.
Called to set the value of the named extended attribute.
=head3 getxattr
Arguments: Pathname, extended attribute's name
+
Returns an errno, 0 if there was no value, or the extended attribute's value.
Called to get the value of the named extended attribute.
=head3 listxattr
Arguments: Pathname
+
Returns a list: 0 or more text strings (the extended attribute names), followed by a numeric errno (usually 0).
=head3 removexattr
Arguments: Pathname, extended attribute's name
+
+Returns an errno or 0 on success.
+
+Removes the named extended attribute (if present) from a file.
+
+=head3 opendir
+
+Arguments: Pathname of a directory
+Returns an errno, and a directory handle (optional)
+
+Called when opening a directory for reading. If special handling is
+required to open a directory, this operation can be implemented to handle
+that.
+
+=head3 readdir
+
+Arguments: Pathname of a directory, numeric offset, (optional) directory handle
+
+Returns a list of 0 or more entries, followed by a numeric errno (usually 0).
+The entries can be simple strings (filenames), or arrays containing an
+offset number, the filename, and optionally an array ref containing the
+stat values (as would be returned from getattr()).
+
+This is used to read entries from a directory. It can be used to return just
+entry names like getdir(), or can get a segment of the available entries,
+which requires using array refs and the 2- or 3-item form, with offset values
+starting from 1. If you wish to return the parameters to fill each entry's
+struct stat, but do not wish to do partial entry lists/entry counting, set
+the first element of each array to 0 always.
+
+Note that if this call is implemented, it overrides getdir() ALWAYS.
+
+=head3 releasedir
+
+Arguments: Pathname of a directory, (optional) directory handle
+
+Returns an errno or 0 on success
+
+Called when there are no more references to an opened directory. Called once
+for each pathname or handle passed to opendir(). Similar to release(), but
+for directories. Accepts a return value, but like release(), the response
+code will not propagate to any corresponding closedir() calls.
+
+=head3 fsyncdir
+
+Arguments: Pathname of a directory, numeric flags, (optional) directory handle
+
Returns an errno or 0 on success.
+Called to synchronize any changes to a directory's contents. If flag is
+non-zero, only synchronize user data, otherwise synchronize user data and
+metadata.
+
+=head3 init
+
+Arguments: None.
+
+Returns (optionally) an SV to be passed as private_data via fuse_get_context().
+
+=head3 destroy
+
+Arguments: (optional) private data SV returned from init(), if any.
+
+Returns nothing.
+
+=head3 access
+
+Arguments: Pathname, access mode flags
+
+Returns an errno or 0 on success.
+
+Determine if the user attempting to access the indicated file has access to
+perform the requested actions. The user ID can be determined by calling
+fuse_get_context(). See access(2) for more information.
+
+=head3 create
+
+Arguments: Pathname, create mask, open mode flags
+
+Returns errno or 0 on success, and (optional) file handle.
+
+Create a file with the path indicated, then open a handle for reading and/or
+writing with the supplied mode flags. Can also return a file handle like
+open() as part of the call.
+
+=head3 ftruncate
+
+Arguments: Pathname, numeric offset, (optional) file handle
+
+Returns errno or 0 on success
+
+Like truncate(), but on an opened file.
+
+=head3 fgetattr
+
+Arguments: Pathname, (optional) file handle
+
+Returns a list, very similar to the 'stat' function (see
+perlfunc). On error, simply return a single numeric scalar
+value (e.g. "return -ENOENT();").
+
+Like getattr(), but on an opened file.
+
+=head3 lock
+
+Arguments: Pathname, numeric command code, hashref containing lock parameters, (optional) file handle
+
+Returns errno or 0 on success
+
+Used to lock or unlock regions of a file. Locking is handled locally, but this
+allows (especially for networked file systems) for protocol-level locking
+semantics to also be employed, if any are available.
+
+See the Fuse documentation for more explanation of lock(). The needed symbols
+for the lock constants can be obtained by importing Fcntl.
+
+=head3 utimens
+
+Arguments: Pathname, last accessed time, last modified time
+
+Returns errno or 0 on success
+
+Like utime(), but allows time resolution down to the nanosecond. By default,
+times are passed as "numeric" (internally these are typically represented
+as "double"), so the sub-second portion is represented as fractions of a
+second. If you want times passed as arrays instead of floating point
+values, for higher precision, you should pass the C<utimens_as_array> option
+to C<Fuse::main>.
+
+Note that if this call is implemented, it overrides utime() ALWAYS.
+
+=head3 bmap
+
+Arguments: Pathname, numeric blocksize, numeric block number
+
+Returns errno or 0 on success, and physical block number if successful
+
+Used to map a block number offset in a file to the physical block offset
+on the block device backing the file system. This is intended for
+filesystems that are stored on an actual block device, with the 'blkdev'
+option passed.
+
+=head3 ioctl
+
+Arguments: Pathname, ioctl command code, flags, data if ioctl op is a write, (optional) file handle
+
+Returns errno or 0 on success, and data if ioctl op is a read
+
+Used to handle ioctl() operations on files. See ioctl(2) for more
+information on the fine details of ioctl operation numbers. May need to
+h2ph system headers to get the necessary macros; keep in mind the macros
+are highly OS-dependent.
+
+Keep in mind that read and write are from the client perspective, so
+read from our end means data is going *out*, and write means data is
+coming *in*. It can be slightly confusing.
+
+=head3 poll
+
+Arguments: Pathname, poll handle ID (or undef if none), event mask, (optional) file handle
+
+Returns errno or 0 on success, and updated event mask on success
+
+Used to handle poll() operations on files. See poll(2) to learn more about
+event polling. Use IO::Poll to get the POLLIN, POLLOUT, and other symbols
+to describe the events which can happen on the filehandle. Save the poll
+handle ID to be passed to C<notify_poll> and C<pollhandle_destroy>
+functions, if it is not undef. Threading will likely be necessary for this
+operation to work.
+
+There is not an "out of band" data transfer channel provided as part of
+FUSE, so POLLPRI/POLLRDBAND/POLLWRBAND won't work.
+
+Poll handle is currently a read-only scalar; we are investigating a way
+to make this an object instead.
+
=head1 AUTHOR
Mark Glines, E<lt>mark@glines.orgE<gt>
projects / perl-fuse.git / blobdiff