path: root/api/src/glfs-handles.h

/*
  Copyright (c) 2013-2018 Red Hat, Inc. <http://www.redhat.com>
  This file is part of GlusterFS.

  This file is licensed to you under your choice of the GNU Lesser
  General Public License, version 3 or any later version (LGPLv3 or
  later), or the GNU General Public License, version 2 (GPLv2), in all
  cases as published by the Free Software Foundation.
*/

#ifndef _GLFS_HANDLES_H
#define _GLFS_HANDLES_H

#include "glfs.h"
#include <inttypes.h>

/* GLFS OBJECT BASED OPERATIONS
 *
 * The following APIs are introduced to provide an API framework that can work
 * with gluster objects (files and directories), instead of absolute paths.
 *
 * The following API set can be related to the POSIX *at interfaces (like
 * openat (2)). The intention of these APIs is to be able to operate based
 * on parent object and looking up or creating child objects within, OR to be
 * used on the actual object thus looked up or created, and retrieve information
 * regarding the same.
 *
 * The APIs also provide for generating an opaque invariant handle to the
 * object, that can later be used to lookup the object, instead of the regular
 * glfs_h_* variants. The APIs that provide this behaviour are,
 * glfs_h_extract_handle and glfs_h_create_from_handle.
 *
 * The object handles can be transitioned to fd based operations as supported
 * by glfs.h calls, using the glfs_h_open call. This provides a way to move
 * from objects to fd's akin to moving from path to fd for required operations.
 *
 * NOTE: The opaque invariant handle is the GFID of the object in reality, but
 * maintained as an opaque data value, for potential internal changes to the
 * same without impacting the caller.
 *
 * NOTE: Currently looking up an object can create multiple object handles to
 * the same, i.e distinct glfs_object *. Hence each such looked up or received
 * handle from other calls, would need to be closed. In the future, for a given
 * object these pointers would be the same, and an ease of use API to forget all
 * instances of this bject would be provided (instead of a per lookup close).
 * This should not change the APIs in their current form.
 *
 */

/* Values for valid flags to be used when using XXXsetattr, to set multiple
 attribute values passed via the related stat structure.
 */
#define GFAPI_SET_ATTR_MODE 0x1
#define GFAPI_SET_ATTR_UID 0x2
#define GFAPI_SET_ATTR_GID 0x4
#define GFAPI_SET_ATTR_SIZE 0x8
#define GFAPI_SET_ATTR_ATIME 0x10
#define GFAPI_SET_ATTR_MTIME 0x20

/* Handle length for object handles returned from glfs_h_extract_handle or
 * glfs_h_create_from_handle */
#define GFAPI_HANDLE_LENGTH 16

/* These flags should be in sync to the ones defined in upcall.h */
#define GFAPI_UP_NLINK 0x00000001 /* update nlink */
#define GFAPI_UP_MODE 0x00000002  /* update mode and ctime */
#define GFAPI_UP_OWN 0x00000004   /* update mode,uid,gid and ctime */
#define GFAPI_UP_SIZE 0x00000008  /* update fsize */
#define GFAPI_UP_TIMES 0x00000010 /* update all times */
#define GFAPI_UP_ATIME 0x00000020 /* update atime only */
#define GFAPI_UP_PERM                                                          \
    0x00000040 /* update fields needed for                                     \
                  permission checking */
#define GFAPI_UP_RENAME                                                        \
    0x00000080 /* this is a rename op -                                        \
                  delete the cache entry */
#define GFAPI_UP_FORGET                                                        \
    0x00000100                           /* inode_forget on server side -      \
                                            invalidate the cache entry */
#define GFAPI_UP_PARENT_TIMES 0x00000200 /* update parent dir times */

#define GFAPI_INODE_UPDATE_FLAGS                                               \
    (GFAPI_UP_NLINK | GFAPI_UP_MODE | GFAPI_UP_OWN | GFAPI_UP_SIZE |           \
     GFAPI_UP_TIMES | GFAPI_UP_ATIME)

/* Portability non glibc c++ build systems */
#ifndef __THROW
#if defined __cplusplus
#define __THROW throw()
#else
#define __THROW
#endif
#endif

__BEGIN_DECLS

/*
 * Notes:
 *
 * The file object handle. One per looked up, created file/directory
 *
 * This had been introduced to facilitate gfid/inode based gfapi
 * - a requirement introduced by nfs-ganesha
 */
struct glfs_object;
typedef struct glfs_object glfs_object_t;

/* Functions for getting details about the glfs_upcall_inode
 *
 * None of the pointers returned by the below functions should be free()'d,
 * glfs_free()'d or glfs_h_close()'d by the application.
 *
 * Releasing of the structures is done by passing the glfs_upcall pointer
 * to glfs_free().
 */
struct glfs_upcall_inode;
typedef struct glfs_upcall_inode glfs_upcall_inode_t;

glfs_object_t *
glfs_upcall_inode_get_object(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_object, 3.7.16);

uint64_t
glfs_upcall_inode_get_flags(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_flags, 3.7.16);

struct stat *
glfs_upcall_inode_get_stat(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_stat, 3.7.16);

uint64_t
glfs_upcall_inode_get_expire(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_expire, 3.7.16);

glfs_object_t *
glfs_upcall_inode_get_pobject(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_pobject, 3.7.16);

struct stat *
glfs_upcall_inode_get_pstat(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_pstat, 3.7.16);

glfs_object_t *
glfs_upcall_inode_get_oldpobject(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_oldpobject, 3.7.16);

struct stat *
glfs_upcall_inode_get_oldpstat(glfs_upcall_inode_t *arg) __THROW
    GFAPI_PUBLIC(glfs_upcall_inode_get_oldpstat, 3.7.16);

/* Handle based operations */
/* Operations that generate handles */
glfs_object_t *
glfs_h_lookupat(glfs_t *fs, glfs_object_t *parent, const char *path,
                struct stat *stat, int follow) __THROW
    GFAPI_PUBLIC(glfs_h_lookupat, 3.7.4);

glfs_object_t *
glfs_h_creat(glfs_t *fs, glfs_object_t *parent, const char *path, int flags,
             mode_t mode, struct stat *sb) __THROW
    GFAPI_PUBLIC(glfs_h_creat, 3.4.2);

glfs_object_t *
glfs_h_mkdir(glfs_t *fs, glfs_object_t *parent, const char *path, mode_t flags,
             struct stat *sb) __THROW GFAPI_PUBLIC(glfs_h_mkdir, 3.4.2);

glfs_object_t *
glfs_h_mknod(glfs_t *fs, glfs_object_t *parent, const char *path, mode_t mode,
             dev_t dev, struct stat *sb) __THROW
    GFAPI_PUBLIC(glfs_h_mknod, 3.4.2);

glfs_object_t *
glfs_h_symlink(glfs_t *fs, glfs_object_t *parent, const char *name,
               const char *data, struct stat *stat) __THROW
    GFAPI_PUBLIC(glfs_h_symlink, 3.4.2);

/* Operations on the actual objects */
int
glfs_h_unlink(glfs_t *fs, glfs_object_t *parent, const char *path) __THROW
    GFAPI_PUBLIC(glfs_h_unlink, 3.4.2);

int
glfs_h_close(glfs_object_t *object) __THROW GFAPI_PUBLIC(glfs_h_close, 3.4.2);

int
glfs_caller_specific_init(void *uid_caller_key, void *gid_caller_key,
                          void *future) __THROW
    GFAPI_PUBLIC(glfs_caller_specific_init, 3.5.0);

int
glfs_h_truncate(glfs_t *fs, glfs_object_t *object, off_t offset) __THROW
    GFAPI_PUBLIC(glfs_h_truncate, 3.4.2);

int
glfs_h_stat(glfs_t *fs, glfs_object_t *object, struct stat *stat) __THROW
    GFAPI_PUBLIC(glfs_h_stat, 3.4.2);

int
glfs_h_statfs(glfs_t *fs, glfs_object_t *object, struct statvfs *stat) __THROW
    GFAPI_PUBLIC(glfs_h_statfs, 3.7.0);

int
glfs_h_getattrs(glfs_t *fs, glfs_object_t *object, struct stat *stat) __THROW
    GFAPI_PUBLIC(glfs_h_getattrs, 3.4.2);

int
glfs_h_getxattrs(glfs_t *fs, glfs_object_t *object, const char *name,
                 void *value, size_t size) __THROW
    GFAPI_PUBLIC(glfs_h_getxattrs, 3.5.1);

int
glfs_h_setattrs(glfs_t *fs, glfs_object_t *object, struct stat *sb,
                int valid) __THROW GFAPI_PUBLIC(glfs_h_setattrs, 3.4.2);

int
glfs_h_setxattrs(glfs_t *fs, glfs_object_t *object, const char *name,
                 const void *value, size_t size, int flags) __THROW
    GFAPI_PUBLIC(glfs_h_setxattrs, 3.5.0);

int
glfs_h_readlink(glfs_t *fs, glfs_object_t *object, char *buf,
                size_t bufsiz) __THROW GFAPI_PUBLIC(glfs_h_readlink, 3.4.2);

int
glfs_h_link(glfs_t *fs, glfs_object_t *linktgt, glfs_object_t *parent,
            const char *name) __THROW GFAPI_PUBLIC(glfs_h_link, 3.4.2);

int
glfs_h_rename(glfs_t *fs, glfs_object_t *olddir, const char *oldname,
              glfs_object_t *newdir, const char *newname) __THROW
    GFAPI_PUBLIC(glfs_h_rename, 3.4.2);

int
glfs_h_removexattrs(glfs_t *fs, glfs_object_t *object, const char *name) __THROW
    GFAPI_PUBLIC(glfs_h_removexattrs, 3.5.1);

/* Operations enabling opaque invariant handle to object transitions */
ssize_t
glfs_h_extract_handle(glfs_object_t *object, unsigned char *handle,
                      int len) __THROW
    GFAPI_PUBLIC(glfs_h_extract_handle, 3.4.2);

/* Given a handle, looks up the inode and creates glfs_object.
 * In addition, if provided 'stat', copies the inode attributes
 */
glfs_object_t *
glfs_h_create_from_handle(glfs_t *fs, unsigned char *handle, int len,
                          struct stat *stat) __THROW
    GFAPI_PUBLIC(glfs_h_create_from_handle, 3.4.2);

/* Operations enabling object handles to fd transitions */
glfs_fd_t *
glfs_h_opendir(glfs_t *fs, glfs_object_t *object) __THROW
    GFAPI_PUBLIC(glfs_h_opendir, 3.4.2);

glfs_fd_t *
glfs_h_open(glfs_t *fs, glfs_object_t *object, int flags) __THROW
    GFAPI_PUBLIC(glfs_h_open, 3.4.2);

int
glfs_h_access(glfs_t *fs, glfs_object_t *object, int mask) __THROW
    GFAPI_PUBLIC(glfs_h_access, 3.6.0);

/*
  SYNOPSIS

  glfs_h_poll_upcall: Poll for upcall events given a 'glfs' object.

  DESCRIPTION

  This API is used to poll for upcall events stored in the
  upcall list. Current users of this API is NFS-Ganesha.
  In case of any event received, it will be mapped appropriately
  into 'glfs_upcall' along with the handle('glfs_object') to be
  passed to NFS-Ganesha.

  In case of success, applications need to check the value of
  cbk->handle to be NON NULL before processing the upcall
  events.

  PARAMETERS

  @fs: glfs object to poll the upcall events for
  @cbk: Pointer that will contain an upcall event for use by the application.
        Application is responsible for free'ing the structure with glfs_free().

  RETURN VALUES

  0   : Success.
  -1  : Error condition, mostly due to out of memory.

*/

int
glfs_h_poll_upcall(glfs_t *fs, glfs_upcall_t **cbk) __THROW
    GFAPI_PUBLIC(glfs_h_poll_upcall, 3.7.16);

int
glfs_h_acl_set(glfs_t *fs, glfs_object_t *object, const acl_type_t type,
               const acl_t acl) __THROW GFAPI_PUBLIC(glfs_h_acl_set, 3.7.0);

acl_t
glfs_h_acl_get(glfs_t *fs, glfs_object_t *object, const acl_type_t type) __THROW
    GFAPI_PUBLIC(glfs_h_acl_get, 3.7.0);

size_t
glfs_h_anonymous_write(glfs_t *fs, glfs_object_t *object, const void *buf,
                       size_t count, off_t offset) __THROW
    GFAPI_PUBLIC(glfs_h_anonymous_write, 3.7.0);

ssize_t
glfs_h_anonymous_read(glfs_t *fs, glfs_object_t *object, const void *buf,
                      size_t count, off_t offset) __THROW
    GFAPI_PUBLIC(glfs_h_anonymous_read, 3.7.0);

/*
 * Caution: The object returned by this object gets freed as part
 * of 'glfs_free(xstat)'. Make sure to have a copy using 'glfs_object_copy()'
 * to use post that.
 */
glfs_object_t *
glfs_xreaddirplus_get_object(struct glfs_xreaddirp_stat *xstat) __THROW
    GFAPI_PUBLIC(glfs_xreaddirplus_get_object, 3.11.0);

/* Applications should close the object returned by this routine
 * explicitly using 'glfs_h_close()'
 */
glfs_object_t *
glfs_object_copy(glfs_object_t *src) __THROW
    GFAPI_PUBLIC(glfs_object_copy, 3.11.0);

int
glfs_h_lease(glfs_t *fs, glfs_object_t *object, glfs_lease_t *lease) __THROW
    GFAPI_PUBLIC(glfs_h_lease, 4.0.0);

glfs_object_t *
glfs_h_find_handle(glfs_t *fs, unsigned char *handle, int len) __THROW
    GFAPI_PUBLIC(glfs_h_lease, 4.0.0);
__END_DECLS

#endif /* !_GLFS_HANDLES_H */