tests/test-shutdown-plugin.c

   1 /* nbdkit
   2  * Copyright Red Hat
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  * * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * * Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  *
  15  * * Neither the name of Red Hat nor the names of its contributors may be
  16  * used to endorse or promote products derived from this software without
  17  * specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  21  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  22  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
  23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  26  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  27  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <config.h>
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #include <nbdkit-plugin.h>
  40
  41 static void
  42 shutdown_unload (void)
  43 {
  44   nbdkit_debug ("clean shutdown");
  45 }
  46
  47 static void *
  48 shutdown_open (int readonly)
  49 {
  50   return NBDKIT_HANDLE_NOT_NEEDED;
  51 }
  52
  53 static int64_t
  54 shutdown_get_size (void *handle)
  55 {
  56   return 1024*1024;
  57 }
  58
  59 #define THREAD_MODEL NBDKIT_THREAD_MODEL_PARALLEL
  60
  61 static int
  62 shutdown_pread (void *handle, void *buf, uint32_t count, uint64_t offset)
  63 {
  64   memset (buf, 0, count);
  65   return 0;
  66 }
  67
  68 /* Writing 0x55 to any location causes a shutdown. */
  69 static int
  70 shutdown_pwrite (void *handle, const void *buf, uint32_t count, uint64_t offset)
  71 {
  72   if (memchr (buf, 0x55, count) != NULL) {
  73     nbdkit_debug ("shutdown triggered!");
  74     nbdkit_shutdown ();
  75   }
  76   return 0;
  77 }
  78
  79 static struct nbdkit_plugin plugin = {
  80   .name              = "shutdown",
  81   .version           = PACKAGE_VERSION,
  82   .unload            = shutdown_unload,
  83   .open              = shutdown_open,
  84   .get_size          = shutdown_get_size,
  85   .pread             = shutdown_pread,
  86   .pwrite            = shutdown_pwrite,
  87 };
  88
  89 NBDKIT_REGISTER_PLUGIN (plugin)