gsf/gsf-shared-memory.c

   1 /* vim: set sw=8: -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
   2 /*
   3  * gsf-shared-memory.c:
   4  *
   5  * Copyright (C) 2002-2006 Morten Welinder (terra@diku.dk)
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of version 2.1 of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation.
  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 Lesser General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
  19  * USA
  20  */
  21
  22 #include <gsf-config.h>
  23 #include <gsf/gsf-shared-memory.h>
  24 #include <gsf/gsf-impl-utils.h>
  25
  26 #ifdef HAVE_MMAP
  27 #include <sys/types.h>
  28 #include <sys/mman.h>
  29 #elif defined(G_OS_WIN32)
  30 #include <windows.h>
  31 #endif
  32
  33 typedef struct {
  34         GObjectClass g_object_class;
  35 } GsfSharedMemoryClass;
  36
  37 static GObjectClass *parent_class;
  38
  39 GsfSharedMemory *
  40 gsf_shared_memory_new (void *buf, gsf_off_t size, gboolean needs_free)
  41 {
  42         GsfSharedMemory *mem = g_object_new (GSF_SHARED_MEMORY_TYPE, NULL);
  43         if (G_UNLIKELY (NULL == mem)) return NULL;
  44
  45         mem->buf = buf;
  46         mem->size = size;
  47         mem->needs_free = needs_free;
  48         mem->needs_unmap = FALSE;
  49         return mem;
  50 }
  51
  52 GsfSharedMemory *
  53 gsf_shared_memory_mmapped_new (void *buf, gsf_off_t size)
  54 {
  55 #if defined(HAVE_MMAP) || defined(G_OS_WIN32)
  56         size_t msize = size;
  57         if ((gsf_off_t)msize != size) {
  58                 g_warning ("memory buffer size too large");
  59                 return NULL;
  60         } else {
  61                 GsfSharedMemory *mem = gsf_shared_memory_new (buf, size, FALSE);
  62                 mem->needs_unmap = TRUE;
  63                 return mem;
  64         }
  65 #else
  66         return NULL;
  67 #endif
  68 }
  69
  70 static void
  71 gsf_shared_memory_finalize (GObject *obj)
  72 {
  73         GsfSharedMemory *mem = (GsfSharedMemory *) (obj);
  74
  75         if (mem->buf != NULL) {
  76                 if (mem->needs_free)
  77                         g_free (mem->buf);
  78                 else if (mem->needs_unmap) {
  79 #ifdef HAVE_MMAP
  80                         munmap (mem->buf, mem->size);
  81 #elif defined(G_OS_WIN32)
  82                         UnmapViewOfFile (mem->buf);
  83 #else
  84                         g_assert_not_reached ();
  85 #endif
  86                 }
  87         }
  88
  89         G_OBJECT_CLASS (parent_class)->finalize (obj);
  90 }
  91
  92 static void
  93 gsf_shared_memory_init (GObject *obj)
  94 {
  95         GsfSharedMemory *mem = (GsfSharedMemory *) (obj);
  96         mem->buf = NULL;
  97 }
  98
  99 static void
 100 gsf_shared_memory_class_init (GObjectClass *gobject_class)
 101 {
 102         parent_class = g_type_class_peek_parent (gobject_class);
 103
 104         gobject_class->finalize = gsf_shared_memory_finalize;
 105 }
 106
 107 GSF_CLASS (GsfSharedMemory, gsf_shared_memory,
 108            gsf_shared_memory_class_init, gsf_shared_memory_init,
 109            G_TYPE_OBJECT)