PIKApp/libpika/pika-shm.c

204 lines
4.7 KiB
C

/* LIBPIKA - The PIKA Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* pika-shm.c
*
* This library is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <errno.h>
#if defined(USE_SYSV_SHM)
#ifdef HAVE_IPC_H
#include <sys/ipc.h>
#endif
#ifdef HAVE_SHM_H
#include <sys/shm.h>
#endif
#elif defined(USE_POSIX_SHM)
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <fcntl.h>
#include <sys/mman.h>
#endif /* USE_POSIX_SHM */
#include <glib.h>
#if defined(G_OS_WIN32) || defined(G_WITH_CYGWIN)
# ifdef STRICT
# undef STRICT
# endif
# define STRICT
# ifdef _WIN32_WINNT
# undef _WIN32_WINNT
# endif
# define _WIN32_WINNT 0x0601
# include <windows.h>
# include <tlhelp32.h>
# undef RGB
# define USE_WIN32_SHM 1
#endif
#include "pika.h"
#include "pika-shm.h"
#define TILE_MAP_SIZE (pika_tile_width () * pika_tile_height () * 32)
#define ERRMSG_SHM_FAILED "Could not attach to pika shared memory segment"
#ifdef USE_WIN32_SHM
static HANDLE _shm_handle;
#endif
static gint _shm_ID = -1;
static guchar *_shm_addr = NULL;
guchar *
_pika_shm_addr (void)
{
return _shm_addr;
}
void
_pika_shm_open (gint shm_ID)
{
_shm_ID = shm_ID;
if (_shm_ID != -1)
{
#if defined(USE_SYSV_SHM)
/* Use SysV shared memory mechanisms for transferring tile data. */
_shm_addr = (guchar *) shmat (_shm_ID, NULL, 0);
if (_shm_addr == (guchar *) -1)
{
g_error ("shmat() failed: %s\n" ERRMSG_SHM_FAILED,
g_strerror (errno));
}
#elif defined(USE_WIN32_SHM)
/* Use Win32 shared memory mechanisms for transferring tile data. */
gchar fileMapName[128];
wchar_t *w_fileMapName;
/* From the id, derive the file map name */
g_snprintf (fileMapName, sizeof (fileMapName), "PIKA%d.SHM", _shm_ID);
w_fileMapName = g_utf8_to_utf16 (fileMapName, -1, NULL, NULL, NULL);
if (!w_fileMapName)
g_error ("Cannot convert to UTF16");
/* Open the file mapping */
_shm_handle = OpenFileMappingW (FILE_MAP_ALL_ACCESS, 0, w_fileMapName);
g_clear_pointer (&w_fileMapName, g_free);
if (_shm_handle)
{
/* Map the shared memory into our address space for use */
_shm_addr = (guchar *) MapViewOfFile (_shm_handle,
FILE_MAP_ALL_ACCESS,
0, 0, TILE_MAP_SIZE);
/* Verify that we mapped our view */
if (!_shm_addr)
{
g_error ("MapViewOfFile error: %lu... " ERRMSG_SHM_FAILED,
GetLastError ());
}
}
else
{
g_error ("OpenFileMapping error: %lu... " ERRMSG_SHM_FAILED,
GetLastError ());
}
#elif defined(USE_POSIX_SHM)
/* Use POSIX shared memory mechanisms for transferring tile data. */
gchar map_file[32];
gint shm_fd;
/* From the id, derive the file map name */
g_snprintf (map_file, sizeof (map_file), "/pika-shm-%d", _shm_ID);
/* Open the file mapping */
shm_fd = shm_open (map_file, O_RDWR, 0600);
if (shm_fd != -1)
{
/* Map the shared memory into our address space for use */
_shm_addr = (guchar *) mmap (NULL, TILE_MAP_SIZE,
PROT_READ | PROT_WRITE, MAP_SHARED,
shm_fd, 0);
/* Verify that we mapped our view */
if (_shm_addr == MAP_FAILED)
{
g_error ("mmap() failed: %s\n" ERRMSG_SHM_FAILED,
g_strerror (errno));
}
close (shm_fd);
}
else
{
g_error ("shm_open() failed: %s\n" ERRMSG_SHM_FAILED,
g_strerror (errno));
}
#endif
}
}
void
_pika_shm_close (void)
{
#if defined(USE_SYSV_SHM)
if ((_shm_ID != -1) && _shm_addr)
shmdt ((char *) _shm_addr);
#elif defined(USE_WIN32_SHM)
if (_shm_handle)
CloseHandle (_shm_handle);
#elif defined(USE_POSIX_SHM)
if ((_shm_ID != -1) && (_shm_addr != MAP_FAILED))
munmap (_shm_addr, TILE_MAP_SIZE);
#endif
}