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#include "../common/tdb_private.h"
#include "../common/io.c"
#include "../common/tdb.c"
#include "../common/lock.c"
#include "../common/freelist.c"
#include "../common/traverse.c"
#include "../common/transaction.c"
#include "../common/error.c"
#include "../common/open.c"
#include "../common/check.c"
#include "../common/hash.c"
#include "../common/mutex.c"
#include "tap-interface.h"
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdarg.h>
#include "logging.h"
static TDB_DATA key, data;
static void do_chainlock(const char *name, int tdb_flags, int up, int down)
{
struct tdb_context *tdb;
int ret;
ssize_t nread, nwritten;
char c = 0;
tdb = tdb_open_ex(name, 3, tdb_flags,
O_RDWR|O_CREAT, 0755, &taplogctx, NULL);
ok(tdb, "tdb_open_ex should succeed");
ret = tdb_chainlock(tdb, key);
ok(ret == 0, "tdb_chainlock should succeed");
nwritten = write(up, &c, sizeof(c));
ok(nwritten == sizeof(c), "write should succeed");
nread = read(down, &c, sizeof(c));
ok(nread == sizeof(c), "read should succeed");
exit(0);
}
static void do_allrecord_lock(const char *name, int tdb_flags, int up, int down)
{
struct tdb_context *tdb;
int ret;
ssize_t nread, nwritten;
char c = 0;
tdb = tdb_open_ex(name, 3, tdb_flags,
O_RDWR|O_CREAT, 0755, &taplogctx, NULL);
ok(tdb, "tdb_open_ex should succeed");
ret = tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT, false);
ok(ret == 0, "tdb_allrecord_lock should succeed");
nwritten = write(up, &c, sizeof(c));
ok(nwritten == sizeof(c), "write should succeed");
nread = read(down, &c, sizeof(c));
ok(nread == sizeof(c), "read should succeed");
exit(0);
}
/* The code should barf on TDBs created with rwlocks. */
static int do_tests(const char *name, int tdb_flags)
{
struct tdb_context *tdb;
int ret;
pid_t chainlock_child, allrecord_child;
int chainlock_down[2];
int chainlock_up[2];
int allrecord_down[2];
int allrecord_up[2];
char c;
ssize_t nread, nwritten;
key.dsize = strlen("hi");
key.dptr = discard_const_p(uint8_t, "hi");
data.dsize = strlen("world");
data.dptr = discard_const_p(uint8_t, "world");
ret = pipe(chainlock_down);
ok(ret == 0, "pipe should succeed");
ret = pipe(chainlock_up);
ok(ret == 0, "pipe should succeed");
ret = pipe(allrecord_down);
ok(ret == 0, "pipe should succeed");
ret = pipe(allrecord_up);
ok(ret == 0, "pipe should succeed");
chainlock_child = fork();
ok(chainlock_child != -1, "fork should succeed");
if (chainlock_child == 0) {
close(chainlock_up[0]);
close(chainlock_down[1]);
close(allrecord_up[0]);
close(allrecord_up[1]);
close(allrecord_down[0]);
close(allrecord_down[1]);
do_chainlock(name, tdb_flags,
chainlock_up[1], chainlock_down[0]);
exit(0);
}
close(chainlock_up[1]);
close(chainlock_down[0]);
nread = read(chainlock_up[0], &c, sizeof(c));
ok(nread == sizeof(c), "read should succeed");
/*
* Now we have a process holding a chainlock. Start another process
* trying the allrecord lock. This will block.
*/
allrecord_child = fork();
ok(allrecord_child != -1, "fork should succeed");
if (allrecord_child == 0) {
close(chainlock_up[0]);
close(chainlock_up[1]);
close(chainlock_down[0]);
close(chainlock_down[1]);
close(allrecord_up[0]);
close(allrecord_down[1]);
do_allrecord_lock(name, tdb_flags,
allrecord_up[1], allrecord_down[0]);
exit(0);
}
close(allrecord_up[1]);
close(allrecord_down[0]);
poll(NULL, 0, 500);
tdb = tdb_open_ex(name, 3, tdb_flags,
O_RDWR|O_CREAT, 0755, &taplogctx, NULL);
ok(tdb, "tdb_open_ex should succeed");
/*
* Someone already holds a chainlock, but we're able to get the
* freelist lock.
*
* The freelist lock/mutex is independent from the allrecord lock/mutex.
*/
ret = tdb_chainlock_nonblock(tdb, key);
ok(ret == -1, "tdb_chainlock_nonblock should not succeed");
ret = tdb_lock_nonblock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_lock_nonblock should succeed");
ret = tdb_unlock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_unlock should succeed");
/*
* We have someone else having done the lock for us. Just mark it.
*/
ret = tdb_chainlock_mark(tdb, key);
ok(ret == 0, "tdb_chainlock_mark should succeed");
/*
* The tdb_store below will block the freelist. In one version of the
* mutex patches, the freelist was already blocked here by the
* allrecord child, which was waiting for the chainlock child to give
* up its chainlock. Make sure that we don't run into this
* deadlock. To exercise the deadlock, just comment out the "ok"
* line.
*
* The freelist lock/mutex is independent from the allrecord lock/mutex.
*/
ret = tdb_lock_nonblock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_lock_nonblock should succeed");
ret = tdb_unlock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_unlock should succeed");
ret = tdb_store(tdb, key, data, TDB_INSERT);
ok(ret == 0, "tdb_store should succeed");
ret = tdb_chainlock_unmark(tdb, key);
ok(ret == 0, "tdb_chainlock_unmark should succeed");
nwritten = write(chainlock_down[1], &c, sizeof(c));
ok(nwritten == sizeof(c), "write should succeed");
nread = read(chainlock_up[0], &c, sizeof(c));
ok(nread == 0, "read should succeed");
nread = read(allrecord_up[0], &c, sizeof(c));
ok(nread == sizeof(c), "read should succeed");
/*
* Someone already holds the allrecord lock, but we're able to get the
* freelist lock.
*
* The freelist lock/mutex is independent from the allrecord lock/mutex.
*/
ret = tdb_chainlock_nonblock(tdb, key);
ok(ret == -1, "tdb_chainlock_nonblock should not succeed");
ret = tdb_lockall_nonblock(tdb);
ok(ret == -1, "tdb_lockall_nonblock should not succeed");
ret = tdb_lock_nonblock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_lock_nonblock should succeed");
ret = tdb_unlock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_unlock should succeed");
/*
* We have someone else having done the lock for us. Just mark it.
*/
ret = tdb_lockall_mark(tdb);
ok(ret == 0, "tdb_lockall_mark should succeed");
ret = tdb_lock_nonblock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_lock_nonblock should succeed");
ret = tdb_unlock(tdb, -1, F_WRLCK);
ok(ret == 0, "tdb_unlock should succeed");
ret = tdb_store(tdb, key, data, TDB_REPLACE);
ok(ret == 0, "tdb_store should succeed");
ret = tdb_lockall_unmark(tdb);
ok(ret == 0, "tdb_lockall_unmark should succeed");
nwritten = write(allrecord_down[1], &c, sizeof(c));
ok(nwritten == sizeof(c), "write should succeed");
nread = read(allrecord_up[0], &c, sizeof(c));
ok(nread == 0, "read should succeed");
close(chainlock_up[0]);
close(chainlock_down[1]);
close(allrecord_up[0]);
close(allrecord_down[1]);
diag("%s tests done", name);
return exit_status();
}
int main(int argc, char *argv[])
{
int ret;
bool mutex_support;
mutex_support = tdb_runtime_check_for_robust_mutexes();
ret = do_tests("marklock-deadlock-fcntl.tdb",
TDB_CLEAR_IF_FIRST |
TDB_INCOMPATIBLE_HASH);
ok(ret == 0, "marklock-deadlock-fcntl.tdb tests should succeed");
if (!mutex_support) {
skip(1, "No robust mutex support, "
"skipping marklock-deadlock-mutex.tdb tests");
return exit_status();
}
ret = do_tests("marklock-deadlock-mutex.tdb",
TDB_CLEAR_IF_FIRST |
TDB_MUTEX_LOCKING |
TDB_INCOMPATIBLE_HASH);
ok(ret == 0, "marklock-deadlock-mutex.tdb tests should succeed");
return exit_status();
}
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