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 #define MSG_BROADCAST_PID_STR   "0:0"
  64
  65 struct messaging_context;
  66 struct messaging_rec;
  67
  68 /*
  69  * struct messaging_context belongs to messages.c, but because we still have
  70  * messaging_dispatch, we need it here. Once we get rid of signals for
  71  * notifying processes, this will go.
  72  */
  73
  74 struct messaging_context {
  75         struct server_id id;
  76         struct tevent_context *event_ctx;
  77         struct messaging_callback *callbacks;
  78
  79         struct tevent_req **waiters;
  80         unsigned num_waiters;
  81
  82         struct messaging_backend *local;
  83         struct messaging_backend *remote;
  84 };
  85
  86 struct messaging_backend {
  87         NTSTATUS (*send_fn)(struct messaging_context *msg_ctx,
  88                             struct server_id pid, int msg_type,
  89                             const DATA_BLOB *data,
  90                             struct messaging_backend *backend);
  91         void *private_data;
  92 };
  93
  94 NTSTATUS messaging_tdb_init(struct messaging_context *msg_ctx,
  95                             TALLOC_CTX *mem_ctx,
  96                             struct messaging_backend **presult);
  97
  98 bool messaging_tdb_parent_init(TALLOC_CTX *mem_ctx);
  99
 100 NTSTATUS messaging_tdb_cleanup(struct messaging_context *msg_ctx,
 101                         struct server_id pid);
 102
 103 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 104                               TALLOC_CTX *mem_ctx,
 105                               struct messaging_backend **presult);
 106 struct ctdbd_connection *messaging_ctdbd_connection(void);
 107
 108 bool message_send_all(struct messaging_context *msg_ctx,
 109                       int msg_type,
 110                       const void *buf, size_t len,
 111                       int *n_sent);
 112 struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 113                                          struct tevent_context *ev);
 114
 115 struct server_id messaging_server_id(const struct messaging_context *msg_ctx);
 116
 117 /*
 118  * re-init after a fork
 119  */
 120 NTSTATUS messaging_reinit(struct messaging_context *msg_ctx);
 121
 122 NTSTATUS messaging_register(struct messaging_context *msg_ctx,
 123                             void *private_data,
 124                             uint32_t msg_type,
 125                             void (*fn)(struct messaging_context *msg,
 126                                        void *private_data,
 127                                        uint32_t msg_type,
 128                                        struct server_id server_id,
 129                                        DATA_BLOB *data));
 130 void messaging_deregister(struct messaging_context *ctx, uint32_t msg_type,
 131                           void *private_data);
 132 NTSTATUS messaging_send(struct messaging_context *msg_ctx,
 133                         struct server_id server,
 134                         uint32_t msg_type, const DATA_BLOB *data);
 135
 136 NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
 137                             struct server_id server, uint32_t msg_type,
 138                             const uint8_t *buf, size_t len);
 139 void messaging_dispatch_rec(struct messaging_context *msg_ctx,
 140                             struct messaging_rec *rec);
 141
 142 struct tevent_req *messaging_read_send(TALLOC_CTX *mem_ctx,
 143                                        struct tevent_context *ev,
 144                                        struct messaging_context *msg,
 145                                        uint32_t msg_type);
 146 int messaging_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 147                         struct messaging_rec **presult);
 148
 149 void messaging_cleanup_server(struct messaging_context *msg_ctx,
 150                                 struct server_id pid);
 151
 152 #include "librpc/gen_ndr/ndr_messaging.h"
 153
 154 #endif