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/* t-lock.c - Check the lock functions
* Copyright (C) 2013, 2015 g10 Code GmbH
*
* This file is part of libgpg-error.
*
* libgpg-error 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 2.1 of
* the License, or (at your option) any later version.
*
* libgpg-error 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <https://www.gnu.org/licenses/>.
*/
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <sys/types.h>
#include <unistd.h>
#ifdef _WIN32
# include <windows.h>
# include <time.h>
#else
# ifdef USE_POSIX_THREADS
# include <pthread.h>
# endif
#endif
#define PGM "t-lock"
#include "t-common.h"
#ifdef _WIN32
# define THREAD_RET_TYPE DWORD WINAPI
# define THREAD_RET_VALUE 0
#else
# define THREAD_RET_TYPE void *
# define THREAD_RET_VALUE NULL
#endif
/* Our tests works by having a a couple of accountant threads which do
random transactions between accounts and a revision threads which
checks that the balance of all accounts is invariant. The idea for
this check is due to Bruno Haible. */
#define N_ACCOUNT 8
#define ACCOUNT_VALUE 42
static int account[N_ACCOUNT];
GPGRT_LOCK_DEFINE (accounts_lock);
/* Number of transactions done by each accountant. */
#define N_TRANSACTIONS 1000
/* Number of accountants to run. */
#define N_ACCOUNTANTS 5
/* Maximum transaction value. A quite low value is used so that we
would get an integer overflow. */
#define MAX_TRANSACTION_VALUE 50
/* Flag to tell the revision thread to finish. */
static volatile int stop_revision_thread;
/* Initialze all accounts. */
static void
init_accounts (void)
{
int i;
for (i=0; i < N_ACCOUNT; i++)
account[i] = ACCOUNT_VALUE;
}
/* Check that the sum of all accounts matches the initial sum. */
static void
check_accounts (void)
{
int i, sum;
sum = 0;
for (i = 0; i < N_ACCOUNT; i++)
sum += account[i];
if (sum != N_ACCOUNT * ACCOUNT_VALUE)
die ("accounts out of balance");
}
static void
print_accounts (void)
{
int i;
for (i=0; i < N_ACCOUNT; i++)
printf ("account %d: %6d\n", i, account[i]);
}
#if defined(_WIN32) || defined(USE_POSIX_THREADS)
/* Get a a random integer value in the range 0 to HIGH. */
static unsigned int
get_rand (int high)
{
return (unsigned int)(1+(int)((double)(high+1)*rand ()/(RAND_MAX+1.0))) - 1;
}
/* Pick a random account. Note that this function is not
thread-safe. */
static int
pick_account (void)
{
return get_rand (N_ACCOUNT - 1);
}
/* Pick a random value for a transaction. This is not thread-safe. */
static int
pick_value (void)
{
return get_rand (MAX_TRANSACTION_VALUE);
}
/* This is the revision department. */
static THREAD_RET_TYPE
revision_thread (void *arg)
{
gpg_err_code_t rc;
int i = 0;
(void)arg;
while (!stop_revision_thread)
{
rc = gpgrt_lock_lock (&accounts_lock);
if (rc)
fail ("gpgrt_lock_lock failed at %d: %s", __LINE__, gpg_strerror (rc));
check_accounts ();
rc = gpgrt_lock_unlock (&accounts_lock);
if (rc)
fail ("gpgrt_lock_unlock failed at %d: %s", __LINE__,gpg_strerror (rc));
if (!(++i%7))
gpgrt_yield ();
}
return THREAD_RET_VALUE;
}
/* This is one of our accountants. */
static THREAD_RET_TYPE
accountant_thread (void *arg)
{
gpg_err_code_t rc;
int i;
int acc1, acc2;
int value;
(void)arg;
#ifdef _WIN32
srand (time(NULL)*getpid()); /* Windows needs it per thread. */
#endif
for (i = 0; i < N_TRANSACTIONS; i++)
{
rc = gpgrt_lock_lock (&accounts_lock);
if (rc)
fail ("gpgrt_lock_lock failed at %d: %s", __LINE__, gpg_strerror (rc));
acc1 = pick_account ();
acc2 = pick_account ();
value = pick_value ();
account[acc1] += value;
account[acc2] -= value;
rc = gpgrt_lock_unlock (&accounts_lock);
if (rc)
fail ("gpgrt_lock_unlock failed at %d: %s", __LINE__,gpg_strerror (rc));
if (i && !(i%8))
gpgrt_yield ();
}
return THREAD_RET_VALUE;
}
#endif /*_WIN32||USE_POSIX_THREADS*/
static void
run_test (void)
{
#ifdef _WIN32
HANDLE rthread;
HANDLE athreads[N_ACCOUNTANTS];
int i;
int rc;
stop_revision_thread = 0;
rthread = CreateThread (NULL, 0, revision_thread, NULL, 0, NULL);
if (!rthread)
die ("error creating revision thread: rc=%d", (int)GetLastError ());
for (i=0; i < N_ACCOUNTANTS; i++)
{
athreads[i] = CreateThread (NULL, 0, accountant_thread, NULL, 0, NULL);
if (!athreads[i])
die ("error creating accountant thread %d: rc=%d",
i, (int)GetLastError ());
}
for (i=0; i < N_ACCOUNTANTS; i++)
{
rc = WaitForSingleObject (athreads[i], INFINITE);
if (rc == WAIT_OBJECT_0)
show ("accountant thread %d has terminated", i);
else
fail ("waiting for accountant thread %d failed: %d",
i, (int)GetLastError ());
CloseHandle (athreads[i]);
}
stop_revision_thread = 1;
rc = WaitForSingleObject (rthread, INFINITE);
if (rc == WAIT_OBJECT_0)
show ("revision thread has terminated");
else
fail ("waiting for revision thread failed: %d", (int)GetLastError ());
CloseHandle (rthread);
#else /*!_WIN32*/
# ifdef USE_POSIX_THREADS
pthread_t rthread;
pthread_t athreads[N_ACCOUNTANTS];
int i;
stop_revision_thread = 0;
pthread_create (&rthread, NULL, revision_thread, NULL);
for (i=0; i < N_ACCOUNTANTS; i++)
pthread_create (&athreads[i], NULL, accountant_thread, NULL);
for (i=0; i < N_ACCOUNTANTS; i++)
{
pthread_join (athreads[i], NULL);
show ("accountant thread %d has terminated", i);
}
stop_revision_thread = 1;
pthread_join (rthread, NULL);
show ("revision thread has terminated");
# else /*!USE_POSIX_THREADS*/
verbose++;
show ("no thread support - skipping test\n", PGM);
verbose--;
# endif /*!USE_POSIX_THREADS*/
#endif /*!_WIN32*/
gpgrt_lock_destroy (&accounts_lock);
}
int
main (int argc, char **argv)
{
int last_argc = -1;
int rc;
if (argc)
{
argc--; argv++;
}
while (argc && last_argc != argc )
{
last_argc = argc;
if (!strcmp (*argv, "--help"))
{
puts (
"usage: ./t-lock [options]\n"
"\n"
"Options:\n"
" --verbose Show what is going on\n"
" --debug Flyswatter\n"
);
exit (0);
}
if (!strcmp (*argv, "--verbose"))
{
verbose = 1;
argc--; argv++;
}
else if (!strcmp (*argv, "--debug"))
{
verbose = debug = 1;
argc--; argv++;
}
}
srand (time(NULL)*getpid());
if (!gpg_error_check_version (GPG_ERROR_VERSION))
{
die ("gpg_error_check_version returned an error");
errorcount++;
}
init_accounts ();
check_accounts ();
run_test ();
check_accounts ();
/* Run a second time to check deinit code. */
run_test ();
check_accounts ();
/* And a third time to test an explicit init. */
rc = gpgrt_lock_init (&accounts_lock);
if (rc)
fail ("gpgrt_lock_init failed at %d: %s", __LINE__, gpg_strerror (rc));
run_test ();
check_accounts ();
if (verbose)
print_accounts ();
return errorcount ? 1 : 0;
}