! (New) File system communication message formats and codes.  This is the
! internal standard way of transmitting requests between internal & external
! file system clients and internal & external file servers.

! Filesystem mailbox names.

%conststring(31) local     file system mailbox = "FILESYSTEM:LOCAL"
%conststring(31) special   file system mailbox = "FILESYSTEM:SPECIAL"
%conststring(31) FAP       file system mailbox = "FILESYSTEM:FAP"
%conststring(31) H2        file system mailbox = "FILESYSTEM:H2"
%conststring(31) NFS       file system mailbox = "FILESYSTEM:NFS"


! Standard message format.  

%recordformat fs message fm(%record(message fm) system header,
                            %integer fsys work,
                            %record(mailbox fm)%name followup mailbox,
                            %integer access token,
                            %integer tag,
                            %integer request,
                            %integer request flags, response flags,
                            %integer status, error code,
                            %string(*)%name textual response,
                            %record(*)%name filename,
                            %integer components translated,
                            %record(*)%name filename 2,
                            %integer components translated 2,
                            %integer file token,
                            %integer mode, compatible mode,
                            %integer block size,
                            %integer byte offset, byte count,
                            %bytename data buffer,
                            %record(*)%name file attributes,
                            %string(*)%name textual data,
                            %integer request specific,
                            %string(*)%name textual data2)


! Request codes are subdivided into two 16-bit parts: the high-order bits
! identify the particular filesystem for which the code is meaningful, while
! the low-order bits identify the particular operation.  Bit-15, if set,
! indicates that the request contains a filename in the "usual place" and that
! the file system module should attempt to translate it as far as possible
! even thought the actual operation is itself not understood -- this allows
! non-standard operations to name files through the standard filesystem
! mechanisms.  Note that interpreters should not expect that this bit will
! necessarily be set for standard request codes.  Not all fields need be
! used for any particular request; variant records were deliberately avoided
! in order not to pre-judge the formats of non-standard requests.

%constinteger filesystem   mask = 16_0FFF0000
%constinteger request      mask = 16_00000FFF

%constinteger interpret filename = 16_00008000

! The request flags field should always be valid: zero is the preferred default,
! meaning that there are no flags specified.  Most flag values are request-
! specific; the following, however,  are universal:
%constinteger non local flag = 16_00010000;  ! User is not co-resident

! Standard requests (filesystem 0)

%constinteger interpret filename request = 16_00008000
! This request asks that the path be examined to check the validity of the
! filename and the existence (if any) of the file.  The only guaranteed
! result is success or an appropriate error status. There is one request
! flag, viz to ask that translation stop at the penultimate filename.
%constinteger stop at penultimate = 1

%constinteger open file request = 16_00008001
! Open takes a filename, together with the requested mode and the compatible
! mode, and returns a file token and block size.  The file system module is
! expected to supply the address of a followup mailbox, to which subsequent
! reads, writes and closes will be directed, and a blocksize for the user's
! runtime support buffer management.

! Open/compatible modes are coded as follows:
%constinteger read       file mode = 16_0001
%constinteger modify     file mode = 16_0002
%constinteger append  to file mode = 16_0004
! The following additional compatible modes can be specified:
%constinteger exchange   file mode = 16_0008
%constinteger link       file mode = 16_0010
! The filesystem is not obliged to honour any compatible mode request exactly,
! but will guarantee that the compatibility constraints will be at least as
! strong as those requested.  Any unsatisfiable requests will be rejected.

! The following request flags can be specified:
%constinteger create if       flag = 16_0001
%constinteger create          flag = 16_0002
%constinteger temporary       flag = 16_0004
%constinteger unique name     flag = 16_0008
%constinteger no inherit      flag = 16_0010


%constinteger close file request = 16_00000002
! Close requires that the token obtained from the open request be supplied.
! Requests will be directed to the followup mailbox supplied in the open
! response.  There will eventually be at least two request flags, viz truncate
! and improper close.
%constinteger auto truncate flag  = 1
%constinteger improper close flag = 2


%constinteger read data request = 16_00000003
%constinteger write data request = 16_00000004
! These two require that the file token be specified, together with the byte
! offset and byte count and the address of the first byte of the buffer.
! The maximal amount to be transferred is specified for the call, the actual
! amount being returned.  Note that the two need not necessarily be the same.
! Filesystems are not obliged to accept transfers on other than the block
! boundary they specified in response to the open request.

%constinteger truncate file request = 16_00000005
! Truncate operates on open files, specified by token.  The new size is
! specified in the byte count field.  Requests will be directed to the followup
! mailbox.


%constinteger make accessible request = 16_00008006
! The file to be made accessible is specified by filename.  This operation is
! provided to "unlock" files which are inaccessible as a result of having been
! improperly closed.


%constinteger create directory request = 16_00008007
! The directory is specified by name.  There is also a local specific version
! of this request which takes a partition number in the request specific field.


%constinteger remove file request = 16_00008008
! The file to be removed is specified by filename.
%constinteger zap full directory flag = 16_8000


%constinteger rename file request = 16_00008009
! The two files to be renamed are specified by filename and filename2.  The
! filesystem module should assume that both filenames have been verified to
! "belong to" it -- cross-filesystem rename attempts will be rejected by the
! user's runtime support at a previous stage.  The filesystem may, of course,
! apply stricter constraints at its discretion.


! The next two are in until such time as we think up a standard way to
! specify the information (i.e. probably permanently).  As different
! filesystems have different protection conventions, it is easiest to use
! a free textual form and put the onus on the file system module to parse it
! and reject anything it doesn't understand.

%constinteger textual file attributes request = 16_0000800A
! This takes a filename, and returns protection, datestamp and file size
! information as textual data, separated by one or more spaces.  

%constinteger textual permit file request = 16_0000800B
! This takes a filename, and protection in textual data.  The exact form of the
! protection specifier is file system specific (unfortunately).

%constinteger last standard request = 16_000B


! Local filesystem requests (filesystem 1)

%constinteger local request = 16_00010000

%constinteger local insert textual translation request = 16_00018001
! This specifies the name by filename and the translation by textual data.
! The translation level is in mode.  For translations which redirect to a
! different filesystem, the exact form of the translation data depends on
! that filesystem; however the first component always specifies the name
! of the filesystem.


%constinteger local get file header request = 16_00018003
! The file is specified by filename, with the buffer specified by data buffer.


%constinteger local create directory request = 16_00018004
! This is much the same as the standard create directory request, except
! that the partition number is specified in the request specific field.
! The local filesystem will default the partition to that of the parent
! directory for the standard request.


%constinteger local obtain attributes request = 16_00018005
%constinteger local modify attributes request = 16_00018006
! These two take a filename and an attributes list.  They allow access to
! attributes which are not available via the standard textual requests.


%constinteger local reload admin data request = 16_00010007
! This request asks the local filesystem manager to reload its username/user-ID
! translation database, allowing users to be added/removed and their various
! privileges and groups modified.  The request is likely to be removed again
! at some later date.  Privilege is required to issue it.


%constinteger local enquire nth entry request = 16_00018008
! This is a nasty hack, and is only in for the benefit of the old-style
! filestore-protocol interpreter.  The request asks that the name of the
! nth entry (specified in request specific) in the directory is returned
! in textual data.

%constinteger local insert ID request = 16_00018009
! Inserts the file ID, specified in "request specific" in the named directory.

%constinteger last local request = 16_0009


! New-style file access protocol remote filesystem (filesystem 2)

%constinteger fap request = 16_00020000


! Old-style 1976-protocol remote filesystem (filesystem 3)

%constinteger old style request = 16_00030000

%constinteger old logon request = 16_00030001
%constinteger old logoff request = 16_00030002
%constinteger old quote request = 16_00030003
! The old protocol requires each user explicitly to log on and off the 
! filestore.  These requests allow the appropriate context to be established
! modified, and broken.

%constinteger old copy file request = 16_00038004
! This request asks that the remote filestore perform a file copy on behalf
! of the local client.  The files are specified in filename and filename2.

%constinteger old set pass request = 16_00030005
! Change the user's password, specified in textual data.

%constinteger last old request = 16_0005


! NFS filesystem (filesystem 4)

%constinteger NFS request = 16_00040000

%end %of %file