source3/include/messages.h

   1 /*
   2    Unix SMB/CIFS implementation.
   3    messages.c header
   4    Copyright (C) Andrew Tridgell 2000
   5    Copyright (C) 2001, 2002 by Martin Pool
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #ifndef _MESSAGES_H_
  22 #define _MESSAGES_H_
  23
  24 /* change the message version with any incompatible changes in the protocol */
  25 #define MESSAGE_VERSION 2
  26
  27 /*
  28  * Special flags passed to message_send. Allocated from the top, lets see when
  29  * it collides with the message types in the lower 16 bits :-)
  30  */
  31
  32 /*
  33  * Under high load, this message can be dropped. Use for notify-style
  34  * messages that are not critical for correct operation.
  35  */
  36 #define MSG_FLAG_LOWPRIORITY            0x80000000
  37
  38
  39 /* Flags to classify messages - used in message_send_all() */
  40 /* Sender will filter by flag. */
  41
  42 #define FLAG_MSG_GENERAL                0x0001
  43 #define FLAG_MSG_SMBD                   0x0002
  44 #define FLAG_MSG_NMBD                   0x0004
  45 #define FLAG_MSG_WINBIND                0x0008
  46 #define FLAG_MSG_PRINT_GENERAL          0x0010
  47 /* dbwrap messages 4001-4999 */
  48 #define FLAG_MSG_DBWRAP                 0x0020
  49
  50 /*
  51  * ctdb gives us 64-bit server ids for messaging_send. This is done to avoid
  52  * pid clashes and to be able to register for special messages like "all
  53  * smbds".
  54  *
  55  * Normal individual server id's have the upper 32 bits to 0, I picked "1" for
  56  * Samba, other subsystems might use something else.
  57  */
  58
  59 #define MSG_SRVID_SAMBA 0x0000000100000000LL
  60
  61 #include "librpc/gen_ndr/server_id.h"
  62
  63 #ifdef CLUSTER_SUPPORT
  64 #define MSG_BROADCAST_PID_STR   "0:0"
  65 #else
  66 #define MSG_BROADCAST_PID_STR   "0"
  67 #endif
  68
  69 struct messaging_context;
  70 struct messaging_rec;
  71
  72 /*
  73  * struct messaging_context belongs to messages.c, but because we still have
  74  * messaging_dispatch, we need it here. Once we get rid of signals for
  75  * notifying processes, this will go.
  76  */
  77
  78 struct messaging_context {
  79         struct server_id id;
  80         struct tevent_context *event_ctx;
  81         struct messaging_callback *callbacks;
  82
  83         struct tevent_req **waiters;
  84         unsigned num_waiters;
  85
  86         struct messaging_backend *local;
  87         struct messaging_backend *remote;
  88 };
  89
  90 struct messaging_backend {
  91         NTSTATUS (*send_fn)(struct messaging_context *msg_ctx,
  92                             struct server_id pid, int msg_type,
  93                             const DATA_BLOB *data,
  94                             struct messaging_backend *backend);
  95         void *private_data;
  96 };
  97
  98 NTSTATUS messaging_tdb_init(struct messaging_context *msg_ctx,
  99                             TALLOC_CTX *mem_ctx,
 100                             struct messaging_backend **presult);
 101
 102 bool messaging_tdb_parent_init(TALLOC_CTX *mem_ctx);
 103
 104 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 105                               TALLOC_CTX *mem_ctx,
 106                               struct messaging_backend **presult);
 107 struct ctdbd_connection *messaging_ctdbd_connection(void);
 108
 109 bool message_send_all(struct messaging_context *msg_ctx,
 110                       int msg_type,
 111                       const void *buf, size_t len,
 112                       int *n_sent);
 113 struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 114                                          struct tevent_context *ev);
 115
 116 struct server_id messaging_server_id(const struct messaging_context *msg_ctx);
 117
 118 /*
 119  * re-init after a fork
 120  */
 121 NTSTATUS messaging_reinit(struct messaging_context *msg_ctx);
 122
 123 NTSTATUS messaging_register(struct messaging_context *msg_ctx,
 124                             void *private_data,
 125                             uint32_t msg_type,
 126                             void (*fn)(struct messaging_context *msg,
 127                                        void *private_data,
 128                                        uint32_t msg_type,
 129                                        struct server_id server_id,
 130                                        DATA_BLOB *data));
 131 void messaging_deregister(struct messaging_context *ctx, uint32_t msg_type,
 132                           void *private_data);
 133 NTSTATUS messaging_send(struct messaging_context *msg_ctx,
 134                         struct server_id server,
 135                         uint32_t msg_type, const DATA_BLOB *data);
 136
 137 NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
 138                             struct server_id server, uint32_t msg_type,
 139                             const uint8_t *buf, size_t len);
 140 void messaging_dispatch_rec(struct messaging_context *msg_ctx,
 141                             struct messaging_rec *rec);
 142
 143 struct tevent_req *messaging_read_send(TALLOC_CTX *mem_ctx,
 144                                        struct tevent_context *ev,
 145                                        struct messaging_context *msg,
 146                                        uint32_t msg_type);
 147 int messaging_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 148                         struct messaging_rec **presult);
 149
 150 #include "librpc/gen_ndr/ndr_messaging.h"
 151
 152 #endif