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#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
int
main (void)
{
int result = 0;
FILE *fp;
size_t c;
char buf[1000];
int fd;
unsigned char *ptr;
size_t ps = sysconf (_SC_PAGESIZE);
void *mem;
/* Create a file and put some data in it. */
fp = tmpfile ();
if (fp == NULL)
{
printf ("Cannot create temporary file: %m\n");
return 1;
}
fd = fileno (fp);
for (c = 0; c < sizeof (buf); ++c)
buf[c] = '0' + (c % 10);
for (c = 0; c < (ps * 4) / sizeof (buf); ++c)
if (fwrite (buf, 1, sizeof (buf), fp) != sizeof (buf))
{
printf ("`fwrite' failed: %m\n");
return 1;
}
fflush (fp);
assert (ps + 1000 < c * sizeof (buf));
/* First try something which is not allowed: map at an offset which is
not modulo the pagesize. */
ptr = mmap (NULL, 1000, PROT_READ, MAP_SHARED, fd, ps - 1);
if (ptr != MAP_FAILED)
{
puts ("mapping at offset with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at offset with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* Try the same for mmap64. */
ptr = mmap64 (NULL, 1000, PROT_READ, MAP_SHARED, fd, ps - 1);
if (ptr != MAP_FAILED)
{
puts ("mapping at offset with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at offset with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* And the same for private mapping. */
ptr = mmap (NULL, 1000, PROT_READ, MAP_PRIVATE, fd, ps - 1);
if (ptr != MAP_FAILED)
{
puts ("mapping at offset with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at offset with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* Try the same for mmap64. */
ptr = mmap64 (NULL, 1000, PROT_READ, MAP_PRIVATE, fd, ps - 1);
if (ptr != MAP_FAILED)
{
puts ("mapping at offset with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at offset with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* Get a valid address. */
mem = malloc (2 * ps);
if (mem != NULL)
{
/* Now we map at an address which is not mod pagesize. */
ptr = mmap (mem + 1, 1000, PROT_READ, MAP_SHARED | MAP_FIXED, fd, ps);
if (ptr != MAP_FAILED)
{
puts ("mapping at address with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at address with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* Try the same for mmap64. */
ptr = mmap64 (mem + 1, 1000, PROT_READ, MAP_SHARED | MAP_FIXED, fd, ps);
if (ptr != MAP_FAILED)
{
puts ("mapping at address with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at address with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* And again for MAP_PRIVATE. */
ptr = mmap (mem + 1, 1000, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, ps);
if (ptr != MAP_FAILED)
{
puts ("mapping at address with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at address with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
/* Try the same for mmap64. */
ptr = mmap64 (mem + 1, 1000, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, ps);
if (ptr != MAP_FAILED)
{
puts ("mapping at address with mod pagesize != 0 succeeded!");
result = 1;
}
else if (errno != EINVAL && errno != ENOSYS)
{
puts ("wrong error value for mapping at address with mod pagesize != 0: %m (should be EINVAL)");
result = 1;
}
free (mem);
}
/* Now map the memory and see whether the content of the mapped area
is correct. */
ptr = mmap (NULL, 1000, PROT_READ, MAP_SHARED, fd, ps);
if (ptr == MAP_FAILED)
{
if (errno != ENOSYS)
{
printf ("cannot mmap file: %m\n");
result = 1;
}
}
else
{
for (c = ps; c < ps + 1000; ++c)
if (ptr[c - ps] != '0' + (c % 10))
{
printf ("wrong data mapped at offset %zd\n", c);
result = 1;
}
}
/* And for mmap64. */
ptr = mmap64 (NULL, 1000, PROT_READ, MAP_SHARED, fd, ps);
if (ptr == MAP_FAILED)
{
if (errno != ENOSYS)
{
printf ("cannot mmap file: %m\n");
result = 1;
}
}
else
{
for (c = ps; c < ps + 1000; ++c)
if (ptr[c - ps] != '0' + (c % 10))
{
printf ("wrong data mapped at offset %zd\n", c);
result = 1;
}
}
/* That's it. */
return result;
}
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