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
  31 /* list of registered backends */
  32 static struct sys_lease_ops *backends;
  33 static uint32_t num_backends;
  34
  35 #define LEASE_BACKEND   "lease:backend"
  36
  37 /*
  38   initialise a system change notify backend
  39 */
  40 _PUBLIC_ struct sys_lease_context *sys_lease_context_create(struct share_config *scfg,
  41                                                             TALLOC_CTX *mem_ctx,
  42                                                             struct tevent_context *ev,
  43                                                             struct imessaging_context *msg,
  44                                                             sys_lease_send_break_fn break_send)
  45 {
  46         struct sys_lease_context *ctx;
  47         const char *bname;
  48         int i;
  49         NTSTATUS status;
  50
  51         if (num_backends == 0) {
  52                 return NULL;
  53         }
  54
  55         if (ev == NULL) {
  56                 return NULL;
  57         }
  58
  59         ctx = talloc_zero(mem_ctx, struct sys_lease_context);
  60         if (ctx == NULL) {
  61                 return NULL;
  62         }
  63
  64         ctx->event_ctx = ev;
  65         ctx->msg_ctx = msg;
  66         ctx->break_send = break_send;
  67
  68         bname = share_string_option(scfg, LEASE_BACKEND, NULL);
  69         if (!bname) {
  70                 talloc_free(ctx);
  71                 return NULL;
  72         }
  73
  74         for (i=0;i<num_backends;i++) {
  75                 if (strcasecmp(backends[i].name, bname) == 0) {
  76                         ctx->ops = &backends[i];
  77                         break;
  78                 }
  79         }
  80
  81         if (!ctx->ops) {
  82                 talloc_free(ctx);
  83                 return NULL;
  84         }
  85
  86         status = ctx->ops->init(ctx);
  87         if (!NT_STATUS_IS_OK(status)) {
  88                 talloc_free(ctx);
  89                 return NULL;
  90         }
  91
  92         return ctx;
  93 }
  94
  95 /*
  96   register a lease backend
  97 */
  98 _PUBLIC_ NTSTATUS sys_lease_register(const struct sys_lease_ops *backend)
  99 {
 100         struct sys_lease_ops *b;
 101         b = talloc_realloc(talloc_autofree_context(), backends,
 102                            struct sys_lease_ops, num_backends+1);
 103         NT_STATUS_HAVE_NO_MEMORY(b);
 104         backends = b;
 105         backends[num_backends] = *backend;
 106         num_backends++;
 107         return NT_STATUS_OK;
 108 }
 109
 110 _PUBLIC_ NTSTATUS sys_lease_init(void)
 111 {
 112         static bool initialized = false;
 113 #define _MODULE_PROTO(init) extern NTSTATUS init(void);
 114         STATIC_sys_lease_MODULES_PROTO;
 115         init_module_fn static_init[] = { STATIC_sys_lease_MODULES };
 116
 117         if (initialized) return NT_STATUS_OK;
 118         initialized = true;
 119
 120         run_init_functions(static_init);
 121
 122         return NT_STATUS_OK;
 123 }
 124
 125 NTSTATUS sys_lease_setup(struct sys_lease_context *ctx,
 126                          struct opendb_entry *e)
 127 {
 128         return ctx->ops->setup(ctx, e);
 129 }
 130
 131 NTSTATUS sys_lease_update(struct sys_lease_context *ctx,
 132                           struct opendb_entry *e)
 133 {
 134         return ctx->ops->update(ctx, e);
 135 }
 136
 137 NTSTATUS sys_lease_remove(struct sys_lease_context *ctx,
 138                           struct opendb_entry *e)
 139 {
 140         return ctx->ops->remove(ctx, e);
 141 }