ceph/src/spdk/include/spdk/notify.h

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright (c) Intel Corporation.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #ifndef SPDK_NOTIFY_H
  35 #define SPDK_NOTIFY_H
  36
  37 #include "spdk/stdinc.h"
  38 #include "spdk/json.h"
  39 #include "spdk/queue.h"
  40
  41 #ifdef __cplusplus
  42 extern "C" {
  43 #endif
  44
  45 /**
  46  * Opaque event type.
  47  */
  48 struct spdk_notify_type;
  49
  50 typedef int (*spdk_notify_foreach_type_cb)(const struct spdk_notify_type *type, void *ctx);
  51
  52 #define SPDK_NOTIFY_MAX_NAME_SIZE 128
  53 #define SPDK_NOTIFY_MAX_CTX_SIZE 128
  54
  55 struct spdk_notify_event {
  56         char type[SPDK_NOTIFY_MAX_NAME_SIZE];
  57         char ctx[SPDK_NOTIFY_MAX_CTX_SIZE];
  58 };
  59
  60 /**
  61  * Callback type for event enumeration.
  62  *
  63  * \param idx Event index
  64  * \param event Event data
  65  * \param ctx User context
  66  * \return Non zero to break iteration.
  67  */
  68 typedef int (*spdk_notify_foreach_event_cb)(uint64_t idx, const struct spdk_notify_event *event,
  69                 void *ctx);
  70
  71 /**
  72  * Register \c type as new notification type.
  73  *
  74  * \note This function is thread safe.
  75  *
  76  * \param type New notification type to register.
  77  * \return registered notification type or NULL on failure.
  78  */
  79 struct spdk_notify_type *spdk_notify_type_register(const char *type);
  80
  81 /**
  82  * Return name of the notification type.
  83  *
  84  * \param type Notification type we are talking about.
  85  * \return Name of notification type.
  86  */
  87 const char *spdk_notify_type_get_name(const struct spdk_notify_type *type);
  88
  89 /**
  90  * Call cb_fn for all event types.
  91  *
  92  * \note Whole function call is under lock so user callback should not sleep.
  93  * \param cb_fn
  94  * \param ctx
  95  */
  96 void spdk_notify_foreach_type(spdk_notify_foreach_type_cb cb_fn, void *ctx);
  97
  98 /**
  99  * Send given notification.
 100  *
 101  * \param type Notification type
 102  * \param ctx Notification context
 103  *
 104  * \return Event index.
 105  */
 106 uint64_t spdk_notify_send(const char *type, const char *ctx);
 107
 108 /**
 109  * Call cb_fn with events from given range.
 110  *
 111  * \note Whole function call is under lock so user callback should not sleep.
 112  *
 113  * \param start_idx First event index
 114  * \param cb_fn User callback function. Return non-zero to break iteration.
 115  * \param max Maximum number of invocations of user calback function.
 116  * \param ctx User context
 117  * \return Number of user callback invocations
 118  */
 119 uint64_t spdk_notify_foreach_event(uint64_t start_idx, uint64_t max,
 120                                    spdk_notify_foreach_event_cb cb_fn, void *ctx);
 121
 122 #ifdef __cplusplus
 123 }
 124 #endif
 125
 126 #endif /* SPDK_NOTIFY_H */