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#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/syslimits.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
int max_error = 5;
#include "common.h"
void dangling_slink(int sub_test, char const slink_to[PATH_MAX]);
void dangling_slink(int sub_test, char const slink_to[PATH_MAX])
{
pid_t child;
subtest = sub_test;
child = fork();
if (child == (pid_t) -1) {
e(1);
return;
} else if (child == (pid_t) 0) {
/* I'm the child. Create a dangling symlink with an absolute path */
int fd;
char buf[4];
/* We don't want to actually write to '/', so instead we pretend */
if (chroot(".") != 0) e(2);
/* Create file 'slink_to' with contents "bar" */
if ((fd = open(slink_to, O_CREAT|O_WRONLY)) == -1) e(3);
if (write(fd, "bar", strlen("bar")) != strlen("bar")) e(4);
close(fd);
if (symlink(slink_to, "a") == -1) e(5); /* Create the symlink */
if (rename(slink_to, "c") == -1) e(6); /* Make it a dangling symlink */
/* Write "foo" to symlink; this should recreate file 'slink_to' with
* contents "foo" */
if ((fd = open("a", O_CREAT|O_WRONLY)) == -1) e(7);
if (write(fd, "foo", strlen("foo")) != strlen("foo")) e(8);
close(fd);
/* Verify 'a' and 'slink_to' contain "foo" */
memset(buf, '\0', sizeof(buf));
if ((fd = open("a", O_RDONLY)) == -1) e(9);
if (read(fd, buf, 3) != 3) e(10);
if (strncmp(buf, "foo", strlen("foo"))) e(11);
close(fd);
memset(buf, '\0', sizeof(buf));
if ((fd = open(slink_to, O_RDONLY)) == -1) e(12);
if (read(fd, buf, 3) != 3) e(13);
if (strncmp(buf, "foo", strlen("foo"))) e(14);
close(fd);
/* Verify 'c' contains 'bar' */
memset(buf, '\0', sizeof(buf));
if ((fd = open("c", O_RDONLY)) == -1) e(15);
if (read(fd, buf, 3) != 3) e(16);
if (strncmp(buf, "bar", strlen("bar"))) e(17);
close(fd);
/* Cleanup created files */
if (unlink(slink_to) == -1) e(18);
if (unlink("c") == -1) e(19);
/* Use the dangling symlink to test mknod(2) following symlinks */
if (mknod("a", S_IFCHR | 0777, makedev(1, 1)) != -1) e(20);
if (errno != EEXIST) e(21);
if (unlink("a") == -1) e(22);
exit(EXIT_SUCCESS);
} else {
int status;
if (wait(&status) == -1) e(7);
}
}
int main(int argc, char *argv[])
{
start(61);
dangling_slink(1, "/abs"); /* Create dangling symlink with absolute path */
dangling_slink(2, "rel"); /* Create dangling symlink with relative path */
quit();
return(-1); /* Unreachable */
}
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