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/* nbdkit
* Copyright Red Hat
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of Red Hat nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#undef NDEBUG /* Keep test strong even for nbdkit built without assertions */
#include <assert.h>
#define NBDKIT_API_VERSION 2
#include <nbdkit-plugin.h>
#include "getline.h"
static const char *msg = "input";
/* Check whether stdin/out match /dev/null */
static bool
stdio_check (void)
{
static int dn = -1;
struct stat st1, st2;
if (dn == -1) {
dn = open ("/dev/null", O_RDONLY);
assert (dn > STDERR_FILENO);
}
if (fstat (dn, &st1) == -1)
assert (false);
if (fstat (STDIN_FILENO, &st2) == -1)
assert (false);
if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
return false;
if (fstat (STDOUT_FILENO, &st2) == -1)
assert (false);
if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
return false;
return true;
}
static void
stdio_dump_plugin (void)
{
char *buf = NULL;
size_t len = 0;
bool check = stdio_check ();
assert (check == false);
/* Reading from stdin during .dump_plugin is unusual, but not forbidden */
if (getline (&buf, &len, stdin) == -1)
assert (false);
/* The point of .dump_plugin is to extend details sent to stdout */
printf ("%s=%s\n", msg, buf);
free (buf);
}
static int
stdio_config (const char *key, const char *value)
{
bool check = stdio_check ();
assert (check == false);
msg = key;
return 0;
}
static int
stdio_config_complete (void)
{
bool check = stdio_check ();
assert (check == false);
if (nbdkit_stdio_safe ()) {
char *buf = NULL;
size_t len = 0;
/* Reading from stdin during .config_complete is safe except under -s */
if (getline (&buf, &len, stdin) == -1)
assert (false);
/* Output during .config_complete is unusual, but not forbidden */
printf ("%s=%s\n", msg, buf);
free (buf);
}
return 0;
}
static int
stdio_get_ready (void)
{
bool check = stdio_check ();
assert (check == false);
return 0;
}
static int
stdio_after_fork (void)
{
bool check = stdio_check ();
assert (check == true);
return 0;
}
static void *
stdio_open (int readonly)
{
bool check = stdio_check ();
assert (check == true);
return NBDKIT_HANDLE_NOT_NEEDED;
}
static int64_t
stdio_get_size (void *handle)
{
bool check = stdio_check ();
assert (check == true);
return 1024*1024;
}
#define THREAD_MODEL NBDKIT_THREAD_MODEL_PARALLEL
static int
stdio_pread (void *handle, void *buf, uint32_t count, uint64_t offset,
uint32_t flags)
{
bool check = stdio_check ();
assert (check == true);
memset (buf, 0, count);
return 0;
}
static struct nbdkit_plugin plugin = {
.name = "stdio",
.version = PACKAGE_VERSION,
.dump_plugin = stdio_dump_plugin,
.config = stdio_config,
.config_complete = stdio_config_complete,
.get_ready = stdio_get_ready,
.after_fork = stdio_after_fork,
.open = stdio_open,
.get_size = stdio_get_size,
.pread = stdio_pread,
};
NBDKIT_REGISTER_PLUGIN (plugin)
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