--- /dev/null
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <signal.h>
+#include <pthread.h>
+#include <string.h>
+#include <signal.h>
+#include <ctype.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <sys/file.h>
+#include <stdarg.h>
+#include <time.h>
+#include "fcntllocks.h"
+
+
+
+pthread_mutex_t gateMutex;
+pthread_cond_t gateBroadCast;
+bool isGateOpen = false;
+int threadsNumber = 20;
+
+
+struct sigaction sigintAction; /*Stores the init SIGINT sigaction value*/
+char *fileName = "/tmp/locks";
+
+
+
+
+
+
+int main (int argc, char *argv[])
+{
+ int c; /*Getopt parameter*/
+ /*Default values*/
+ struct sigaction sa; /*sig actions values*/
+
+ opterr = 0;
+ while ((c = getopt (argc, argv, "p:t:f:")) != -1) {
+ switch (c) {
+ case 'p':
+ fileName = optarg;
+ break;
+ case 't':
+ threadsNumber = atoi(optarg);
+ break;
+ case '?':
+ if ((optopt == 'p') || (optopt == 't') || (optopt == 'f'))
+ fprintf (stderr, "Option -%c requires an argument.\n", optopt);
+ else if (isprint (optopt))
+ fprintf (stderr, "Invalid option '-%c'.\n", optopt);
+ else
+ fprintf (stderr, "Unknown option character '\\x%x'.\n", optopt);
+ return -1;
+ default:
+ abort ();
+ }
+ }
+
+ /*This program does not admit options*/
+ if (optind < argc) {
+ fprintf (stderr, "This program does not admit options just argument elements with their values.\n");
+ return -1;
+ }
+
+
+ /* If running from console, user may finish this process using SIGINT (Ctrl-C)*/
+ /* Check to make sure that the shell has not set up an initial action of SIG_IGN before I establish my own signal handler.
+ * As seen on http://www.gnu.org/software/libc/manual/html_node/Initial-Signal-Actions.html#Initial-Signal-Actions
+ */
+ memset (&sa, 0, sizeof(sa));
+ memset (&sigintAction, 0, sizeof(sigaction));
+ if (sigaction (SIGINT, NULL, &sa) < 0) {
+ fprintf (stderr, "%s: %s\n", "SIGINT retrieve current signal handler failed:", strerror(errno));
+
+ return -1;
+ }
+
+ if (sa.sa_handler != SIG_IGN) {
+ /* Save the current SIGINT sigaction value. We use it to restore SIGINT handler in my custom SIGINT handler.*/
+ memcpy (&sigintAction, &sa, sizeof(sigaction));
+
+ sa.sa_handler = &sigint_handler;
+ sa.sa_flags = SA_RESTART;
+ if (sigemptyset(&sa.sa_mask) < 0) {
+ fprintf (stderr, "%s: %s\n", "SIGINT empty mask", strerror(errno));
+
+ return -1;
+ }
+ if (sigaction(SIGINT, &sa, NULL) < 0) {
+ fprintf (stderr, "%s: %s\n", "SIGINT set signal handler failed", strerror(errno));
+
+ return -1;
+ }
+ }
+
+ if (threadsNumber > 0) {
+ return test_threads_concurrency();
+ } else {
+ return test_require_user();
+ }
+
+ return 0;
+}
+
+int test_threads_concurrency()
+{
+ int returnValue = 0;
+ int createIndex;
+ int joinIndex;
+ pthread_t threadIds [threadsNumber]; /*Threads identifier numbers*/
+
+ pthread_mutex_init(&gateMutex, NULL);
+ pthread_cond_init(&gateBroadCast, NULL);
+ closeGate();
+
+
+ for (createIndex = 0; createIndex < threadsNumber; createIndex++) {
+ print_with_date (stdout, "Thread %d created\n", createIndex);
+ if (pthread_create (&threadIds[createIndex], NULL, &thread_lock, (void *) createIndex) != 0 ) {
+ print_with_date (stderr, "Thread %d creation failed\n", createIndex, strerror(errno));
+ returnValue = -1;
+ break;
+ }
+ }
+
+ sleep(5);
+ openGate();
+
+ for (joinIndex = createIndex; joinIndex --> 0; ) {
+ if (pthread_join(threadIds[joinIndex], NULL) != 0) {
+ print_with_date (stderr, "Thread %d join error\n", joinIndex, strerror(errno));
+ returnValue = -1;
+ }
+ }
+
+ return returnValue;
+}
+
+void *thread_lock(void * arg)
+{
+ struct flock fl;
+ int threadNumber;
+ int fd;
+ int flockErr;
+
+ threadNumber = (int) arg;
+
+
+ fd = open(fileName, O_CREAT | O_RDWR, 0664);
+ if (fd == -1) {
+ goto end;
+ print_with_date (stderr, "Thread %d, open file error", threadNumber, strerror(errno));
+ }
+
+
+ gate();
+
+
+ fl.l_type = F_WRLCK;
+ fl.l_whence = SEEK_SET;
+ fl.l_start = 0;
+ fl.l_len = 0;
+ fl.l_pid = getpid();
+ print_with_date (stdout, "Thread %d: before lock\n", threadNumber);
+ do {
+ flockErr = fcntl(fd, F_SETLKW, &fl);
+ } while(flockErr == -1 && errno == EINTR);
+
+ if (flockErr == -1) {
+ print_with_date (stderr, "Thread %d: F_WRLCK/F_SETLKW, exclusive lock error", threadNumber, strerror(errno));
+ goto end;
+ }
+ print_with_date (stdout, "Thread %d: after lock\n", threadNumber);
+
+
+ sleep(5);
+
+
+ print_with_date(stdout, "Thread %d: before release lock\n", threadNumber);
+ fl.l_type = F_UNLCK;
+ do {
+ fcntl(fd, F_SETLK, &fl);
+ } while(flockErr == -1 && errno == EINTR);
+
+ if (flockErr == -1) {
+ print_with_date(stderr, "Thread %d: F_UNLCK unlock error", threadNumber, strerror(errno));
+ goto end;
+ }
+ print_with_date(stdout, "Thread %d: after release lock\n", threadNumber);
+
+
+end:
+ close (fd);
+ pthread_exit(0);
+}
+
+int test_require_user() {
+ struct flock fl;
+ int returnValue = -1;
+ int fd;
+ int flockErr;
+
+
+ fd = open(fileName, O_CREAT | O_RDWR, 0664);
+ if (fd == -1) {
+ print_with_date(stderr, "Open file error", strerror(errno));
+ goto end;
+ }
+
+
+ fprintf(stdout, "Press ENTER key for locking file: %s\n", fileName);
+ fflush(stdout);
+ getchar();
+
+
+ fl.l_type = F_WRLCK;
+ fl.l_whence = SEEK_SET;
+ fl.l_start = 0;
+ fl.l_len = 0;
+ fl.l_pid = getpid();
+ print_with_date (stdout, "Before lock\n");
+ do {
+ flockErr = fcntl(fd, F_SETLKW, &fl);
+ } while(flockErr == -1 && errno == EINTR);
+
+ if (flockErr == -1) {
+ print_with_date (stderr, "F_WRLCK/F_SETLKW, exclusive lock error", strerror(errno));
+ goto end;
+ }
+ print_with_date (stdout, "After lock\n");
+
+
+ fprintf(stdout, "Press ENTER key for unlocking file: %s\n", fileName);
+ fflush(stdout);
+ getchar();
+
+
+ print_with_date(stdout, "Before release lock\n");
+ fl.l_type = F_UNLCK;
+ do {
+ fcntl(fd, F_SETLK, &fl);
+ } while(flockErr == -1 && errno == EINTR);
+
+ if (flockErr == -1) {
+ print_with_date(stderr, "F_UNLCK unlock error", strerror(errno));
+ goto end;
+ }
+ print_with_date(stdout, "After release lock\n");
+
+
+ returnValue = 0;
+end:
+ close (fd);
+ return returnValue;
+}
+
+int print_with_date(FILE *stream, const char *format, ...) {
+ va_list arg;
+ int done;
+ time_t rawtime;
+ char buff[100];
+ char msg[50];
+ char dateformatter[100] = "%s: ";
+ struct tm timeinfo;
+
+ time ( &rawtime);
+ localtime_r ( &rawtime, &timeinfo);
+ strftime(buff, 50, "%Y-%m-%d %H:%M:%S", &timeinfo);
+
+ va_start (arg, format);
+ vsnprintf (msg , 50, format, arg);
+
+ strcat(dateformatter, msg);
+ done = fprintf (stream, dateformatter, buff, msg);
+ va_end (arg);
+
+ if (done < 0) {
+ fflush (stream);
+ return done;
+ } else {
+ done = fflush (stream);
+ return done;
+ }
+}
+
+void gate() {
+
+ pthread_mutex_lock(&gateMutex);
+
+ while(!isGateOpen) {
+ pthread_cond_wait(&gateBroadCast, &gateMutex);
+ }
+
+ pthread_mutex_unlock(&gateMutex);
+}
+
+void openGate() {
+ pthread_mutex_lock(&gateMutex);
+
+ isGateOpen = true;
+ pthread_cond_broadcast(&gateBroadCast);
+
+ pthread_mutex_unlock(&gateMutex);
+}
+
+void closeGate() {
+ pthread_mutex_lock(&gateMutex);
+
+ isGateOpen = false;
+
+ pthread_mutex_unlock(&gateMutex);
+}
+
+void sigint_handler(int sig)
+{
+ if (sigaction(SIGINT, &sigintAction, NULL) < 0) {
+ exit (EXIT_FAILURE);
+ }
+ kill(getpid(), SIGINT);
+}
+
+
projects / CForFun.git / commitdiff