source4/ntvfs/sysdep/sys_lease.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Stefan Metzmacher 2008
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 /*
  21   abstract the various kernel interfaces to leases (oplocks) into a
  22   single Samba friendly interface
  23 */
  24
  25 #include "includes.h"
  26 #include "system/filesys.h"
  27 #include "ntvfs/sysdep/sys_lease.h"
  28 #include "../lib/util/dlinklist.h"
  29 #include "param/param.h"
  30 #include "lib/util/samba_modules.h"
  31
  32 /* list of registered backends */
  33 static struct sys_lease_ops *backends;
  34 static uint32_t num_backends;
  35
  36 #define LEASE_BACKEND   "lease:backend"
  37
  38 /*
  39   initialise a system change notify backend
  40 */
  41 _PUBLIC_ struct sys_lease_context *sys_lease_context_create(struct share_config *scfg,
  42                                                             TALLOC_CTX *mem_ctx,
  43                                                             struct tevent_context *ev,
  44                                                             struct imessaging_context *msg,
  45                                                             sys_lease_send_break_fn break_send)
  46 {
  47         struct sys_lease_context *ctx;
  48         const char *bname;
  49         int i;
  50         NTSTATUS status;
  51
  52         if (num_backends == 0) {
  53                 return NULL;
  54         }
  55
  56         if (ev == NULL) {
  57                 return NULL;
  58         }
  59
  60         ctx = talloc_zero(mem_ctx, struct sys_lease_context);
  61         if (ctx == NULL) {
  62                 return NULL;
  63         }
  64
  65         ctx->event_ctx = ev;
  66         ctx->msg_ctx = msg;
  67         ctx->break_send = break_send;
  68
  69         bname = share_string_option(scfg, LEASE_BACKEND, NULL);
  70         if (!bname) {
  71                 talloc_free(ctx);
  72                 return NULL;
  73         }
  74
  75         for (i=0;i<num_backends;i++) {
  76                 if (strcasecmp(backends[i].name, bname) == 0) {
  77                         ctx->ops = &backends[i];
  78                         break;
  79                 }
  80         }
  81
  82         if (!ctx->ops) {
  83                 talloc_free(ctx);
  84                 return NULL;
  85         }
  86
  87         status = ctx->ops->init(ctx);
  88         if (!NT_STATUS_IS_OK(status)) {
  89                 talloc_free(ctx);
  90                 return NULL;
  91         }
  92
  93         return ctx;
  94 }
  95
  96 /*
  97   register a lease backend
  98 */
  99 _PUBLIC_ NTSTATUS sys_lease_register(const struct sys_lease_ops *backend)
 100 {
 101         struct sys_lease_ops *b;
 102         b = talloc_realloc(talloc_autofree_context(), backends,
 103                            struct sys_lease_ops, num_backends+1);
 104         NT_STATUS_HAVE_NO_MEMORY(b);
 105         backends = b;
 106         backends[num_backends] = *backend;
 107         num_backends++;
 108         return NT_STATUS_OK;
 109 }
 110
 111 _PUBLIC_ NTSTATUS sys_lease_init(void)
 112 {
 113         static bool initialized = false;
 114 #define _MODULE_PROTO(init) extern NTSTATUS init(void);
 115         STATIC_sys_lease_MODULES_PROTO;
 116         init_module_fn static_init[] = { STATIC_sys_lease_MODULES };
 117
 118         if (initialized) return NT_STATUS_OK;
 119         initialized = true;
 120
 121         run_init_functions(static_init);
 122
 123         return NT_STATUS_OK;
 124 }
 125
 126 NTSTATUS sys_lease_setup(struct sys_lease_context *ctx,
 127                          struct opendb_entry *e)
 128 {
 129         return ctx->ops->setup(ctx, e);
 130 }
 131
 132 NTSTATUS sys_lease_update(struct sys_lease_context *ctx,
 133                           struct opendb_entry *e)
 134 {
 135         return ctx->ops->update(ctx, e);
 136 }
 137
 138 NTSTATUS sys_lease_remove(struct sys_lease_context *ctx,
 139                           struct opendb_entry *e)
 140 {
 141         return ctx->ops->remove(ctx, e);
 142 }