[SOLVED] CS代考计算机代写 file system /* Deletes and closes file that is mapped into memory

/* Deletes and closes file that is mapped into memory
and verifies that it can still be read through the mapping. */

#include
#include
#include “tests/vm/sample.inc”
#include “tests/lib.h”
#include “tests/main.h”

void
test_main (void)
{
char *actual = (char *) 0x10000000;
int handle;
mapid_t map;
size_t i;

/* Map file. */
CHECK ((handle = open (“sample.txt”)) > 1, “open ”sample.txt””);
CHECK ((map = mmap (handle, actual)) != MAP_FAILED, “mmap ”sample.txt””);

/* Close file and delete it. */
close (handle);
CHECK (remove (“sample.txt”), “remove ”sample.txt””);
CHECK (open (“sample.txt”) == -1, “try to open ”sample.txt””);

/* Create a new file in hopes of overwriting data from the old
one, in case the file system has incorrectly freed the
file’s data. */
CHECK (create (“another”, 4096 * 10), “create ”another””);

/* Check that mapped data is correct. */
if (memcmp (actual, sample, strlen (sample)))
fail (“read of mmap’d file reported bad data”);

/* Verify that data is followed by zeros. */
for (i = strlen (sample); i < 4096; i++)if (actual[i] != 0)fail (“byte %zu of mmap’d region has value %02hhx (should be 0)”,i, actual[i]);munmap (map);}