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/* Copyright (C) 2009 Mikael Lund Jepsen <mlj@iccc.dk>
*
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/wait.h>
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
char shared_name[] = "/sharetest";
int test_data[11] = {0,1,2,3,4,5,6,7,8,9,10};
int main(void) {
int pfds[2];
pid_t pid;
int fd;
int test_data_fails = 0;
char *ptest_data;
unsigned int i;
char buf[30];
int rv;
pipe(pfds);
switch(pid = fork()) {
case -1:
perror("fork");
exit(1); /* parent exits */
case 0:
/* Child */
/* wait for parent */
read(pfds[0], buf, 5);
fd = shm_open(shared_name, O_RDWR, DEFFILEMODE);
if (fd == -1) {
perror("CHILD - shm_open(existing):");
exit(1);
} else {
ptest_data = mmap(0, sizeof(test_data), PROT_READ + PROT_WRITE, MAP_SHARED, fd, 0);
if (ptest_data != MAP_FAILED) {
for (i=0; i < ARRAY_SIZE(test_data); i++) {
if (ptest_data[i] != test_data[i]) {
printf("%-40s: Offset %d, local %d, shm %d\n", "Compare memory error", i, test_data[i], ptest_data[i]);
test_data_fails++;
}
}
if (test_data_fails == 0)
printf("%-40s: %s\n", "Compare memory", "Success");
munmap(ptest_data, sizeof(test_data));
}
}
exit(0);
default:
/* Parent */
fd = shm_open(shared_name, O_RDWR+O_CREAT+O_EXCL, DEFFILEMODE );
if (fd == -1) {
perror("PARENT - shm_open(create):");
} else {
if ((ftruncate(fd, sizeof(test_data))) == -1)
{
printf("%-40s: %s", "ftruncate", strerror(errno));
shm_unlink(shared_name);
return 0;
}
ptest_data = mmap(0, sizeof(test_data), PROT_READ + PROT_WRITE, MAP_SHARED, fd, 0);
if (ptest_data == MAP_FAILED)
{
perror("PARENT - mmap:");
if (shm_unlink(shared_name) == -1) {
perror("PARENT - shm_unlink:");
}
return 0;
}
for (i=0; i < ARRAY_SIZE(test_data); i++)
ptest_data[i] = test_data[i];
/* signal child */
write(pfds[1], "rdy", 5);
/* wait for child */
wait(&rv);
/* Cleanup */
munmap(ptest_data, sizeof(test_data));
if (shm_unlink(shared_name) == -1) {
perror("PARENT - shm_unlink:");
}
}
}
return 0;
}
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