mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-24 14:00:30 +00:00
366cce74d2
Replacing an outdated comment (namespace setup is now handled by support_fuse_init).
218 lines
10 KiB
C
218 lines
10 KiB
C
/* Facilities for FUSE-backed file system tests.
|
|
Copyright (C) 2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library 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.
|
|
|
|
The GNU C Library 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 the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
/* To run FUSE tests under valgrind, pass the
|
|
--sim-hints=fuse-compatible option to valgrind. This option tells
|
|
valgrind that additional system calls effectively call back into
|
|
the current program. */
|
|
|
|
#ifndef SUPPORT_FUSE_H
|
|
#define SUPPORT_FUSE_H
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
|
|
#include <support/bundled/linux/include/uapi/linux/fuse.h>
|
|
|
|
/* This function must be called furst, before support_fuse_mount, to
|
|
prepare unprivileged mounting. */
|
|
void support_fuse_init (void);
|
|
|
|
/* This function can be called instead of support_fuse_init. It does
|
|
not use mount and user namespaces, so it requires root privileges,
|
|
and cleanup after testing may be incomplete. This is intended only
|
|
for test development. */
|
|
void support_fuse_init_no_namespace (void);
|
|
|
|
/* Opaque type for tracking FUSE mount state. */
|
|
struct support_fuse;
|
|
|
|
/* This function disables a mount point created using
|
|
support_fuse_mount. */
|
|
void support_fuse_unmount (struct support_fuse *) __nonnull ((1));
|
|
|
|
/* This function is called on a separate thread after calling
|
|
support_fuse_mount. F is the mount state, and CLOSURE the argument
|
|
that was passed to support_fuse_mount. The callback function is
|
|
expected to call support_fuse_next to read packets from the kernel
|
|
and handle them according to the test's need. */
|
|
typedef void (*support_fuse_callback) (struct support_fuse *f, void *closure);
|
|
|
|
/* This function creates a new mount point, implemented by CALLBACK.
|
|
CLOSURE is passed to CALLBACK as the second argument. */
|
|
struct support_fuse *support_fuse_mount (support_fuse_callback callback,
|
|
void *closure)
|
|
__nonnull ((1)) __attr_dealloc (support_fuse_unmount, 1);
|
|
|
|
/* This function returns the path to the mount point for F. The
|
|
returned string is valid until support_fuse_unmount (F) is called. */
|
|
const char * support_fuse_mountpoint (struct support_fuse *f) __nonnull ((1));
|
|
|
|
|
|
/* Renders the OPCODE as a string (FUSE_* constant. The caller must
|
|
free the returned string. */
|
|
char * support_fuse_opcode (uint32_t opcode) __attr_dealloc_free;
|
|
|
|
/* Use to provide a checked cast facility. Use the
|
|
support_fuse_in_cast macro below. */
|
|
void *support_fuse_cast_internal (struct fuse_in_header *, uint32_t)
|
|
__nonnull ((1));
|
|
void *support_fuse_cast_name_internal (struct fuse_in_header *, uint32_t,
|
|
size_t skip, char **name)
|
|
__nonnull ((1));
|
|
|
|
/* The macro expansion support_fuse_in_cast (P, TYPE) casts the
|
|
pointer INH to the appropriate type corresponding to the FUSE_TYPE
|
|
opcode. It fails (terminates the process) if INH->opcode does not
|
|
match FUSE_TYPE. The type of the returned pointer matches that of
|
|
the FUSE_* constant.
|
|
|
|
Maintenance note: Adding support for additional struct fuse_*_in
|
|
types is generally easy, except when there is trailing data after
|
|
the struct (see below for support_fuse_cast_name, for example), and
|
|
the kernel has changed struct sizes over time. This has happened
|
|
recently with struct fuse_setxattr_in, and would require special
|
|
handling if implemented. */
|
|
#define support_fuse_payload_type_INIT struct fuse_init_in
|
|
#define support_fuse_payload_type_LOOKUP char
|
|
#define support_fuse_payload_type_OPEN struct fuse_open_in
|
|
#define support_fuse_payload_type_READ struct fuse_read_in
|
|
#define support_fuse_payload_type_SETATTR struct fuse_setattr_in
|
|
#define support_fuse_payload_type_WRITE struct fuse_write_in
|
|
#define support_fuse_cast(typ, inh) \
|
|
((support_fuse_payload_type_##typ *) \
|
|
support_fuse_cast_internal ((inh), FUSE_##typ))
|
|
|
|
/* Same as support_fuse_cast, but also writes the passed name to *NAMEP. */
|
|
#define support_fuse_payload_name_type_CREATE struct fuse_create_in
|
|
#define support_fuse_payload_name_type_MKDIR struct fuse_mkdir_in
|
|
#define support_fuse_cast_name(typ, inh, namep) \
|
|
((support_fuse_payload_name_type_##typ *) \
|
|
support_fuse_cast_name_internal \
|
|
((inh), FUSE_##typ, sizeof (support_fuse_payload_name_type_##typ), \
|
|
(namep)))
|
|
|
|
/* This function should be called from the callback function. It
|
|
returns NULL if the mount point has been unmounted. The result can
|
|
be cast using support_fuse_in_cast. The pointer is invalidated
|
|
with the next call to support_fuse_next.
|
|
|
|
Typical use involves handling some basics using the
|
|
support_fuse_handle_* building blocks, following by a switch
|
|
statement on the result member of the returned struct, to implement
|
|
what a particular test needs. Casts to payload data should be made
|
|
using support_fuse_in_cast.
|
|
|
|
By default, FUSE_FORGET responses are filtered. See
|
|
support_fuse_filter_forget for turning that off. */
|
|
struct fuse_in_header *support_fuse_next (struct support_fuse *f)
|
|
__nonnull ((1));
|
|
|
|
/* This function can be called from a callback function to handle
|
|
basic aspects of directories (OPENDIR, GETATTR, RELEASEDIR).
|
|
inh->nodeid is used as the inode number for the directory. This
|
|
function must be called after support_fuse_next. */
|
|
bool support_fuse_handle_directory (struct support_fuse *f) __nonnull ((1));
|
|
|
|
/* This function can be called from a callback function to handle
|
|
access to the mount point itself, after call support_fuse_next. */
|
|
bool support_fuse_handle_mountpoint (struct support_fuse *f) __nonnull ((1));
|
|
|
|
/* If FILTER_ENABLED, future support_fuse_next calls will not return
|
|
FUSE_FORGET events (and simply discared them, as they require no
|
|
reply). If !FILTER_ENABLED, the callback needs to handle
|
|
FUSE_FORGET events and call support_fuse_no_reply. */
|
|
void support_fuse_filter_forget (struct support_fuse *f, bool filter_enabled)
|
|
__nonnull ((1));
|
|
|
|
/* This function should be called from the callback function after
|
|
support_fuse_next returned a non-null pointer. It sends out a
|
|
response packet on the FUSE device with the supplied payload data. */
|
|
void support_fuse_reply (struct support_fuse *f,
|
|
const void *payload, size_t payload_size)
|
|
__nonnull ((1)) __attr_access ((__read_only__, 2, 3));
|
|
|
|
/* This function should be called from the callback function. It
|
|
replies to a request with an error indicator. ERROR must be positive. */
|
|
void support_fuse_reply_error (struct support_fuse *f, uint32_t error)
|
|
__nonnull ((1));
|
|
|
|
/* This function should be called from the callback function. It
|
|
sends out an empty (but success-indicating) reply packet. */
|
|
void support_fuse_reply_empty (struct support_fuse *f) __nonnull ((1));
|
|
|
|
/* Do not send a reply. Only to be used after a support_fuse_next
|
|
call that returned a FUSE_FORGET event. */
|
|
void support_fuse_no_reply (struct support_fuse *f) __nonnull ((1));
|
|
|
|
/* Specific reponse preparation functions. The returned object can be
|
|
updated as needed. If a NODEID argument is present, it will be
|
|
used to set the inode and FUSE nodeid fields. Without such an
|
|
argument, it is initialized from the current request (if the reply
|
|
requires this field). This function must be called after
|
|
support_fuse_next. The actual response must be sent using
|
|
support_fuse_reply_prepared (or a support_fuse_reply_error call can
|
|
be used to cancel the response). */
|
|
struct fuse_entry_out *support_fuse_prepare_entry (struct support_fuse *f,
|
|
uint64_t nodeid)
|
|
__nonnull ((1));
|
|
struct fuse_attr_out *support_fuse_prepare_attr (struct support_fuse *f)
|
|
__nonnull ((1));
|
|
|
|
/* Similar to the other support_fuse_prepare_* functions, but it
|
|
prepares for two response packets. They can be updated through the
|
|
pointers written to *OUT_ENTRY and *OUT_OPEN prior to calling
|
|
support_fuse_reply_prepared. */
|
|
void support_fuse_prepare_create (struct support_fuse *f,
|
|
uint64_t nodeid,
|
|
struct fuse_entry_out **out_entry,
|
|
struct fuse_open_out **out_open)
|
|
__nonnull ((1, 3, 4));
|
|
|
|
|
|
/* Prepare sending a directory stream. Must be called after
|
|
support_fuse_next and before support_fuse_dirstream_add. */
|
|
struct support_fuse_dirstream;
|
|
struct support_fuse_dirstream *support_fuse_prepare_readdir (struct
|
|
support_fuse *f);
|
|
|
|
/* Adds directory using D_INO, D_OFF, D_TYPE, D_NAME to the directory
|
|
stream D. Must be called after support_fuse_prepare_readdir.
|
|
|
|
D_OFF is the offset of the next directory entry, not the current
|
|
one. The first entry has offset zero. The first requested offset
|
|
can be obtained from the READ payload (struct fuse_read_in) prior
|
|
to calling this function.
|
|
|
|
Returns true if the entry could be added to the buffer, or false if
|
|
there was insufficient room. Sending the buffer is delayed until
|
|
support_fuse_reply_prepared is called. */
|
|
bool support_fuse_dirstream_add (struct support_fuse_dirstream *d,
|
|
uint64_t d_ino, uint64_t d_off,
|
|
uint32_t d_type,
|
|
const char *d_name);
|
|
|
|
/* Send a prepared response. Must be called after one of the
|
|
support_fuse_prepare_* functions and before the next
|
|
support_fuse_next call. */
|
|
void support_fuse_reply_prepared (struct support_fuse *f) __nonnull ((1));
|
|
|
|
#endif /* SUPPORT_FUSE_H */
|