source/smbd/process_model.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    process model manager - main loop
   4    Copyright (C) Andrew Tridgell 1992-2003
   5    Copyright (C) James J Myers 2003 <myersjj@samba.org>
   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 2 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, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23 #include "lib/events/events.h"
  24 #include "smb_server/smb_server.h"
  25
  26 /*
  27   setup the events for the chosen process model
  28 */
  29 const struct model_ops *process_model_startup(struct event_context *ev, const char *model)
  30 {
  31         const struct model_ops *ops;
  32
  33         ops = process_model_byname(model);
  34         if (!ops) {
  35                 DEBUG(0,("Unknown process model '%s'\n", model));
  36                 exit(-1);
  37         }
  38
  39         ops->model_init(ev);
  40
  41         return ops;
  42 }
  43
  44 /* the list of currently registered process models */
  45 static struct process_model {
  46         struct model_ops *ops;
  47 } *models = NULL;
  48 static int num_models;
  49
  50 /*
  51   register a process model.
  52
  53   The 'name' can be later used by other backends to find the operations
  54   structure for this backend.
  55 */
  56 NTSTATUS register_process_model(const void *_ops)
  57 {
  58         const struct model_ops *ops = _ops;
  59
  60         if (process_model_byname(ops->name) != NULL) {
  61                 /* its already registered! */
  62                 DEBUG(0,("PROCESS_MODEL '%s' already registered\n",
  63                          ops->name));
  64                 return NT_STATUS_OBJECT_NAME_COLLISION;
  65         }
  66
  67         models = realloc_p(models, struct process_model, num_models+1);
  68         if (!models) {
  69                 smb_panic("out of memory in register_process_model");
  70         }
  71
  72         models[num_models].ops = smb_xmemdup(ops, sizeof(*ops));
  73         models[num_models].ops->name = smb_xstrdup(ops->name);
  74
  75         num_models++;
  76
  77         DEBUG(3,("PROCESS_MODEL '%s' registered\n",
  78                  ops->name));
  79
  80         return NT_STATUS_OK;
  81 }
  82
  83 /*
  84   return the operations structure for a named backend of the specified type
  85 */
  86 const struct model_ops *process_model_byname(const char *name)
  87 {
  88         int i;
  89
  90         for (i=0;i<num_models;i++) {
  91                 if (strcmp(models[i].ops->name, name) == 0) {
  92                         return models[i].ops;
  93                 }
  94         }
  95
  96         return NULL;
  97 }
  98
  99 /*
 100   return the PROCESS_MODEL module version, and the size of some critical types
 101   This can be used by process model modules to either detect compilation errors, or provide
 102   multiple implementations for different smbd compilation options in one module
 103 */
 104 const struct process_model_critical_sizes *process_model_version(void)
 105 {
 106         static const struct process_model_critical_sizes critical_sizes = {
 107                 PROCESS_MODEL_VERSION,
 108                 sizeof(struct model_ops)
 109         };
 110
 111         return &critical_sizes;
 112 }