use warnings;
use Errno;
use Carp;
+use Config;
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
# This allows declaration use Fuse ':all';
# If you do not need this, moving things directly into @EXPORT or @EXPORT_OK
# will save memory.
-our %EXPORT_TAGS = ( 'all' => [ qw(
- FUSE_DEBUG
-) ] );
+our %EXPORT_TAGS = (
+ 'all' => [ qw(XATTR_CREATE XATTR_REPLACE fuse_get_context fuse_version) ],
+ 'xattr' => [ qw(XATTR_CREATE XATTR_REPLACE) ]
+ );
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
-our @EXPORT = qw(
- FUSE_DEBUG
-);
-our $VERSION = '0.05';
+our @EXPORT = ();
+our $VERSION = '0.13';
sub AUTOLOAD {
# This AUTOLOAD is used to 'autoload' constants from the constant()
bootstrap Fuse $VERSION;
sub main {
- my (@subs) = (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
- my (@names) = qw(getattr readlink getdir mknod mkdir unlink rmdir symlink
- rename link chmod chown truncate utime open read write statfs);
- my ($tmp) = 0;
- my (%mapping) = map { $_ => $tmp++ } (@names);
- my (%otherargs) = (debug=>0, mountpoint=>"");
+ 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);
+ my $fuse_version = fuse_version();
+ if ($fuse_version >= 2.3) {
+ push(@names, qw/opendir readdir releasedir fsyncdir init destroy/);
+ }
+ if ($fuse_version >= 2.5) {
+ push(@names, qw/access create ftruncate fgetattr/);
+ }
+ if ($fuse_version >= 2.6) {
+ push(@names, qw/lock utimens bmap/);
+ }
+# 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 nullpath_ok);
+ my %otherargs = (
+ debug => 0,
+ threaded => 0,
+ mountpoint => "",
+ mountopts => "",
+ nullpath_ok => 0,
+ );
while(my $name = shift) {
my ($subref) = shift;
if(exists($otherargs{$name})) {
$otherargs{$name} = $subref;
} else {
croak "There is no function $name" unless exists($mapping{$name});
- croak "Usage: Fuse::main(getattr => &my_getattr, ...)" unless $subref;
- croak "Usage: Fuse::main(getattr => &my_getattr, ...)" unless ref($subref);
- croak "Usage: Fuse::main(getattr => &my_getattr, ...)" unless ref($subref) eq "CODE";
+ croak "Usage: Fuse::main(getattr => \"main::my_getattr\", ...)" unless $subref;
$subs[$mapping{$name}] = $subref;
}
}
- perl_fuse_main($otherargs{debug},$otherargs{mountpoint},@subs);
+ if($otherargs{threaded}) {
+ # make sure threads are both available, and loaded.
+ if($Config{useithreads}) {
+ if(exists($threads::{VERSION})) {
+ if(exists($threads::shared::{VERSION})) {
+ # threads will work.
+ } else {
+ carp("Thread support requires you to use threads::shared.\nThreads are disabled.\n");
+ $otherargs{threaded} = 0;
+ }
+ } else {
+ carp("Thread support requires you to use threads and threads::shared.\nThreads are disabled.\n");
+ $otherargs{threaded} = 0;
+ }
+ } else {
+ carp("Thread support was not compiled into this build of perl.\nThreads are disabled.\n");
+ $otherargs{threaded} = 0;
+ }
+ }
+ perl_fuse_main(@otherargs{@otherargs},@subs);
}
# Autoload methods go after =cut, and are processed by the autosplit program.
use Fuse;
my ($mountpoint) = "";
$mountpoint = shift(@ARGV) if @ARGV;
- Fuse::main(mountpoint=>$mountpoint, getattr=>\&my_getattr, getdir=>\&my_getdir, ...);
+ Fuse::main(mountpoint=>$mountpoint, getattr=>"main::my_getattr", getdir=>"main::my_getdir", ...);
=head1 DESCRIPTION
FUSE expects you to implement callbacks for the various functions.
-NOTE: I have only tested the things implemented in example.pl!
-It should work, but some things may not.
-
In the following definitions, "errno" can be 0 (for a success),
-EINVAL, -ENOENT, -EONFIRE, any integer less than 1 really.
etc) can be imported either from POSIX or from Fcntl, often both.
See their respective documentations, for more information.
-=head2 EXPORT
+=head2 EXPORTED SYMBOLS
None by default.
-=head2 EXPORTABLE CONSTANTS
+You can request all exportable symbols by using the tag ":all".
-None.
+You can request the extended attribute symbols by using the tag ":xattr".
+This will export XATTR_CREATE and XATTR_REPLACE.
=head2 FUNCTIONS
=back
-unthreaded => boolean
+mountopts => string
+
+=over 1
+
+This is a comma seperated list of mount options to pass to the FUSE kernel
+module.
+
+At present, it allows the specification of the allow_other
+argument when mounting the new FUSE filesystem. To use this, you will also
+need 'user_allow_other' in /etc/fuse.conf as per the FUSE documention
+
+ mountopts => "allow_other" or
+ mountopts => ""
+
+=back
+
+threaded => boolean
=over 1
-This turns FUSE multithreading off and on. NOTE: This perlmodule does not
-currently work properly in multithreaded mode! The author is unfortunately
-not familiar enough with perl-threads internals, and according to the
-documentation available at time of writing (2002-03-08), those internals are
-subject to changing anyway. Note that singlethreaded mode also means that
-you will not have to worry about reentrancy, though you will have to worry
-about recursive lookups (since the kernel holds a global lock on your
-filesystem and blocks waiting for one callback to complete before calling
-another).
+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
+means that you will not have to worry about reentrancy, though you will have to
+worry about recursive lookups. In single-threaded mode, FUSE holds a global
+lock on your filesystem, and will wait for one callback to return before
+calling another. This can lead to deadlocks, if your script makes any attempt
+to access files or directories in the filesystem it is providing. (This
+includes calling stat() on the mount-point, statfs() calls from the 'df'
+command, and so on and so forth.) It is worth paying a little attention and
+being careful about this.
+
+Enabling multithreading will cause FUSE to make multiple simultaneous calls
+into the various callback functions of your perl script. If you enable
+threaded mode, you can enjoy all the parallel execution and interactive
+response benefits of threads, and you get to enjoy all the benefits of race
+conditions and locking bugs, too. Please also ensure any other perl modules
+you're using are also thread-safe.
+
+(If enabled, this option will cause a warning if your perl interpreter was not
+built with USE_ITHREADS, or if you have failed to use threads or
+threads::shared.)
+
+=back
+
+nullpath_ok => boolean
-I hope to add full multithreading functionality later, but for now, I
-recommend you leave this option at the default, 1 (which means
-unthreaded, no threads will be used and no reentrancy is needed).
+=over 1
+
+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.
=back
+=head3 Fuse::fuse_get_context
+
+ use Fuse "fuse_get_context";
+ my $caller_uid = fuse_get_context()->{"uid"};
+ my $caller_gid = fuse_get_context()->{"gid"};
+ my $caller_pid = fuse_get_context()->{"pid"};
+
+Access context information about the current Fuse operation.
+
+=head3 Fuse::fuse_version
+
+Indicates the Fuse version in use; more accurately, indicates the version
+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".
+
=head2 FUNCTIONS YOUR FILESYSTEM MAY IMPLEMENT
=head3 getattr
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. Its opendir(), readdir(), filldir() and closedir() all in one call.
+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 open
Arguments: Pathname, numeric flags (which is an OR-ing of stuff like O_RDONLY
-and O_SYNC, constants you can import from POSIX).
-Returns an errno.
+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().
+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)
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 requestedsize, numeric offset.
+Arguments: Pathname, numeric requested size, numeric offset, file handle
Returns a numeric errno, or a string scalar with up to $requestedsize bytes of data.
Called in an attempt to fetch a portion of the file.
=head3 write
-Arguments: Pathname, scalar buffer, numeric offset. You can use length($buffer) to
+Arguments: Pathname, scalar buffer, numeric offset, file handle. You can use length($buffer) to
find the buffersize.
-Returns an errno.
+Returns length($buffer) if successful (number of bytes written).
-Called in an attempt to write (or overwrite) a portion of the file. Be prepared because $buffer could contain random binary data with NULLs and all sorts of other wonderful stuff.
+Called in an attempt to write (or overwrite) a portion of the file. Be prepared because $buffer could contain random binary data with NULs and all sorts of other wonderful stuff.
=head3 statfs
-ENOANO(), $namelen, $files, $files_free, $blocks, $blocks_avail, $blocksize
+=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
+is closed. It may be called multiple times before a file is closed.
+
+=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
+for every file with the same pathname and flags as were passed to open.
+
+=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,
+only synchronise the user data. Otherwise synchronise the user and meta data.
+
+=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.
+
+If you wish to reject setting of a particular form of extended attribute name
+(e.g.: regexps matching user\..* or security\..*), then return - EOPNOTSUPP.
+
+If flags is set to XATTR_CREATE and the extended attribute already exists,
+this should fail with - EEXIST. If flags is set to XATTR_REPLACE
+and the extended attribute doesn't exist, this should fail with - ENOATTR.
+
+XATTR_CREATE and XATTR_REPLACE are provided by this module, but not exported
+by default. To import them:
+
+ use Fuse ':xattr';
+
+or:
+
+ use Fuse ':all';
+
+=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.
+
+=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. Currently
+times are passed as "numeric" (internally I believe these are represented
+typically as "long double"), so the sub-second portion is represented as
+fractions of a second.
+
+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.
+
=head1 AUTHOR
Mark Glines, E<lt>mark@glines.orgE<gt>
projects / perl-fuse.git / blobdiff