source4/lib/com/tables.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    COM class tables
   4    Copyright (C) 2004 Jelmer Vernooij <jelmer@samba.org>
   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 2 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, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22 #include "../lib/util/dlinklist.h"
  23 #include "lib/com/com.h"
  24 #include "librpc/gen_ndr/ndr_misc.h"
  25
  26 /* Specific implementation of one or more interfaces */
  27 struct com_class
  28 {
  29         const char *progid;
  30         struct GUID clsid;
  31
  32         struct IUnknown *class_object;
  33         struct com_class *prev, *next;
  34 } * running_classes = NULL;
  35
  36 static struct IUnknown *get_com_class_running(const struct GUID *clsid)
  37 {
  38         struct com_class *c = running_classes;
  39
  40         while(c) {
  41
  42                 if (GUID_equal(clsid, &c->clsid)) {
  43                         return c->class_object;
  44                 }
  45
  46                 c = c->next;
  47         }
  48
  49         return NULL;
  50 }
  51
  52 static struct IUnknown *get_com_class_so(TALLOC_CTX *mem_ctx, const struct GUID *clsid)
  53 {
  54         char *module_name;
  55         char *clsid_str;
  56         void *mod;
  57         get_class_object_function f;
  58
  59         clsid_str = GUID_string(mem_ctx, clsid);
  60         module_name = talloc_asprintf(mem_ctx, "%s.so", clsid_str);
  61         talloc_free(clsid_str);
  62
  63         mod = dlopen(module_name, 0);
  64
  65         if (!mod) {
  66                 return NULL;
  67         }
  68
  69         f = dlsym(mod, "get_class_object");
  70
  71         if (!f) {
  72                 dlclose(mod);
  73                 return NULL;
  74         }
  75
  76         return f(clsid);
  77 }
  78
  79 struct IUnknown *com_class_by_clsid(struct com_context *ctx, const struct GUID *clsid)
  80 {
  81         struct IUnknown *c;
  82
  83         /* Check list of running COM classes first */
  84         c = get_com_class_running(clsid);
  85
  86         if (c != NULL) {
  87                 return c;
  88         }
  89
  90         c = get_com_class_so(ctx, clsid);
  91
  92         if (c != NULL) {
  93                 return c;
  94         }
  95
  96         return NULL;
  97 }
  98
  99 NTSTATUS com_register_running_class(struct GUID *clsid, const char *progid, struct IUnknown *p)
 100 {
 101         struct com_class *l = talloc_zero(running_classes?running_classes:talloc_autofree_context(), struct com_class);
 102
 103         l->clsid = *clsid;
 104         l->progid = talloc_strdup(l, progid);
 105         l->class_object = p;
 106
 107         DLIST_ADD(running_classes, l);
 108
 109         return NT_STATUS_OK;
 110 }