xenstorevar.h

/******************************************************************************
 * xenstorevar.h
 *
 * Method declarations and structures for accessing the XenStore.h
 *
 * Copyright (C) 2005 Rusty Russell, IBM Corporation
 * Copyright (C) 2005 XenSource Ltd.
 * Copyright (C) 2009,2010 Spectra Logic Corporation
 * 
 * This file may be distributed separately from the Linux kernel, or
 * incorporated into other software packages, subject to the following license:
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this source file (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * $FreeBSD$
 */
 
#ifndef _XEN_XENSTORE_XENSTOREVAR_H
#define _XEN_XENSTORE_XENSTOREVAR_H
 
#include <sys/queue.h>
#include <sys/bus.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/sbuf.h>
 
#include <machine/stdarg.h>
 
#include <xen/xen-os.h>
#include <contrib/xen/grant_table.h>
#include <contrib/xen/io/xenbus.h>
#include <contrib/xen/io/xs_wire.h>
 
#include "xenbus_if.h"
 
/* XenStore allocations including XenStore data returned to clients. */
MALLOC_DECLARE(M_XENSTORE);
 
struct xs_watch;
 
typedef void (xs_watch_cb_t)(struct xs_watch *, const char **vec,
    unsigned int len);
 
/* Register callback to watch subtree (node) in the XenStore. */
struct xs_watch
{
        LIST_ENTRY(xs_watch) list;
 
        /* Path being watched. */
        char *node;
 
        /* Callback (executed in a process context with no locks held). */
        xs_watch_cb_t *callback;
 
        /* Callback client data untouched by the XenStore watch mechanism. */
        uintptr_t callback_data;
 
        /* Maximum number of pending watch events to be delivered. */
        unsigned int max_pending;
 
        /*
         * Private counter used by xenstore to keep track of the pending
         * watches. Protected by xs.watch_events_lock.
         */
        unsigned int pending;
};
LIST_HEAD(xs_watch_list, xs_watch);
 
typedef int (*xs_event_handler_t)(void *);
 
struct xs_transaction
{
        uint32_t id;
};
 
#define XST_NIL ((struct xs_transaction) { 0 })
 
bool xs_initialized(void);
 
evtchn_port_t xs_evtchn(void);
 
vm_paddr_t xs_address(void);
 
int xs_directory(struct xs_transaction t, const char *dir,
    const char *node, unsigned int *num, const char ***result);
 
int xs_exists(struct xs_transaction t, const char *dir, const char *node);
 
int xs_read(struct xs_transaction t, const char *dir,
    const char *node, unsigned int *len, void **result);
 
int xs_write(struct xs_transaction t, const char *dir,
    const char *node, const char *string);
 
int xs_mkdir(struct xs_transaction t, const char *dir,
    const char *node);
 
int xs_rm(struct xs_transaction t, const char *dir, const char *node);
 
int xs_rm_tree(struct xs_transaction t, const char *dir,
    const char *node);
 
int xs_transaction_start(struct xs_transaction *t);
 
int xs_transaction_end(struct xs_transaction t, int abort);
 
/*
 * Single file read and scanf parsing of the result.
 *
 * \param t           The XenStore transaction covering this request.
 * \param dir         The dirname of the path to read.
 * \param node        The basename of the path to read.
 * \param scancountp  The number of input values assigned (i.e. the result
 *                    of scanf).
 * \param fmt         Scanf format string followed by a variable number of
 *                    scanf input arguments.
 *
 * \return  On success, 0. Otherwise an errno value indicating the
 *          type of failure.
 */
int xs_scanf(struct xs_transaction t,
    const char *dir, const char *node, int *scancountp, const char *fmt, ...)
    __attribute__((format(scanf, 5, 6)));
 
int xs_printf(struct xs_transaction t, const char *dir,
    const char *node, const char *fmt, ...)
    __attribute__((format(printf, 4, 5)));
 
int xs_vprintf(struct xs_transaction t, const char *dir,
    const char *node, const char *fmt, va_list ap);
 
int xs_gather(struct xs_transaction t, const char *dir, ...);
 
int xs_register_watch(struct xs_watch *watch);
 
void xs_unregister_watch(struct xs_watch *watch);
 
struct sbuf *xs_join(const char *, const char *);
 
void xs_lock(void);
 
void xs_unlock(void);
 
#endif /* _XEN_XENSTORE_XENSTOREVAR_H */