@@ -81,8 +81,16 @@ void noprintf(char *string, ...)
#define MAXT 30 /* default number of threads to create. */
#define MAXR 1000 /* default number of repatetions to execute */
-#define WRITER 0 /* cause thread function to shmat and write */
-#define READER 1 /* cause thread function to shmat and read */
+
+struct child_args
+{
+ pthread_t threadid;
+ int num_reps;
+ int shmkey;
+ int map_size;
+ int isReader;
+};
+
/******************************************************************************/
/* */
@@ -166,28 +174,25 @@ static int rm_shared_mem(key_t shm_id, /* id of shared memory segment to be remo
/* Return: exits with -1 on error, 0 on success */
/* */
/******************************************************************************/
-static void *shmat_rd_wr(void *args)
+static void *shmat_rd_wr(void *vargs)
{ /* arguments to the thread function */
int shmndx = 0; /* index to the number of attach and detach */
int index = 0; /* index to the number of blocks touched */
- int reader = 0; /* this thread is a reader thread if set to 1 */
key_t shm_id = 0; /* shared memory id */
- long *locargs = /* local pointer to arguments */
- (long *)args;
+ struct child_args *args = (struct child_args *)vargs;
volatile int exit_val = 0; /* exit value of the pthread */
char *read_from_mem; /* ptr to touch each (4096) block in memory */
char *write_to_mem; /* ptr to touch each (4096) block in memory */
char *shmat_addr; /* address of the attached memory */
char buff; /* temporary buffer */
- reader = (int)locargs[3];
- while (shmndx++ < (int)locargs[0]) {
+ while (shmndx++ < args->num_reps) {
dprt("pid[%d]: shmat_rd_wr(): locargs[1] = %#x\n",
- getpid(), (int)locargs[1]);
+ getpid(), args->shmkey);
/* get shared memory id */
if ((shm_id =
- shmget((int)locargs[1], (int)locargs[2], IPC_CREAT | 0666))
+ shmget(args->shmkey, args->map_size, IPC_CREAT | 0666))
== -1) {
dprt("pid[%d]: shmat_rd_wr(): shmget failed\n",
getpid());
@@ -213,11 +218,11 @@ static void *shmat_rd_wr(void *args)
"pid[%d]: do_shmat_shmadt(): got shmat address = %#lx\n",
getpid(), (long)shmat_addr);
- if (!reader) {
+ if (args->isReader) {
/* write character 'Y' to that memory area */
index = 0;
write_to_mem = shmat_addr;
- while (index < (int)locargs[2]) {
+ while (index < args->num_reps) {
dprt("pid[%d]: do_shmat_shmatd(): write_to_mem = %#x\n", getpid(), write_to_mem);
*write_to_mem = 'Y';
index++;
@@ -228,7 +233,7 @@ static void *shmat_rd_wr(void *args)
/* read from the memory area */
index = 0;
read_from_mem = shmat_addr;
- while (index < (int)locargs[2]) {
+ while (index < args->num_reps) {
buff = *read_from_mem;
index++;
read_from_mem++;
@@ -272,12 +277,11 @@ int main(int argc, /* number of input parameters */
int c; /* command line options */
int num_thrd = MAXT; /* number of threads to create */
int num_reps = MAXR; /* number of repatitions the test is run */
- int thrd_ndx; /* index into the array of thread ids */
+ int i;
void *th_status; /* exit status of LWP's */
int map_size; /* size of the file mapped. */
int shmkey = 1969; /* key used to generate shmid by shmget() */
- pthread_t thrdid[30]; /* maxinum of 30 threads allowed */
- long chld_args[4]; /* arguments to the thread function */
+ struct child_args chld_args[30]; /* arguments to the thread function */
char *map_address = NULL;
/* address in memory of the mapped file */
extern int optopt; /* options to the program */
@@ -299,7 +303,7 @@ int main(int argc, /* number of input parameters */
case 't':
if ((num_thrd = atoi(optarg)) == 0)
OPT_MISSING(argv[0], optopt);
- else if (num_thrd < 0) {
+ else if (num_thrd < 0 || num_thrd > MAXT) {
fprintf(stdout,
"WARNING: bad argument. Using default\n");
num_thrd = MAXT;
@@ -311,31 +315,27 @@ int main(int argc, /* number of input parameters */
}
}
- chld_args[0] = num_reps;
-
- for (thrd_ndx = 0; thrd_ndx < num_thrd; thrd_ndx += 2) {
+ for (i = 0; i < num_thrd; i += 2) {
srand(time(NULL) % 100);
- map_size =
- (1 + (int)(1000.0 * rand() / (RAND_MAX + 1.0))) * 4096;
-
- chld_args[1] = shmkey++;
- chld_args[2] = map_size;
+ map_size = (1 + (int)(1000.0 * rand() / (RAND_MAX + 1.0))) * 4096;
dprt("main(): thrd_ndx = %d map_address = %#x map_size = %d\n",
- thrd_ndx, map_address, map_size);
-
- chld_args[3] = WRITER;
+ i, map_address, map_size);
+ chld_args[i].num_reps = num_reps;
+ chld_args[i].map_size = map_size;
+ chld_args[i].shmkey = shmkey++;
+ chld_args[i].isReader = 0;
if (pthread_create
- (&thrdid[thrd_ndx], NULL, shmat_rd_wr, chld_args)) {
+ (&chld_args[i].threadid, NULL, shmat_rd_wr, &chld_args[i])) {
perror("shmat_rd_wr(): pthread_create()");
exit(-1);
}
- chld_args[3] = READER;
-
+ chld_args[i + 1] = chld_args[i];
+ chld_args[i + 1].isReader = 1;
if (pthread_create
- (&thrdid[thrd_ndx + 1], NULL, shmat_rd_wr, chld_args)) {
+ (&chld_args[i + 1].threadid, NULL, shmat_rd_wr, &chld_args[i + 1])) {
perror("shmat_rd_wr(): pthread_create()");
exit(-1);
}
@@ -343,8 +343,8 @@ int main(int argc, /* number of input parameters */
sync();
- for (thrd_ndx = 0; thrd_ndx < num_thrd; thrd_ndx++) {
- if (pthread_join(thrdid[thrd_ndx], &th_status) != 0) {
+ for (i = 0; i < num_thrd; i++) {
+ if (pthread_join(chld_args[i].threadid, &th_status) != 0) {
perror("shmat_rd_wr(): pthread_join()");
exit(-1);
} else {
@@ -352,7 +352,7 @@ int main(int argc, /* number of input parameters */
if (th_status == (void *)-1) {
fprintf(stderr,
"thread [%ld] - process exited with errors\n",
- (long)thrdid[thrd_ndx]);
+ (long)chld_args[i].threadid);
exit(-1);
}
}