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#include <stdlib.h>
#include "pagedir.h"
#include "thread.h"
/* verfy_*_lenght are intended to be used in a system call that accept
* parameters containing suspisious (user mode) adresses. The
* operating system (executng the system call in kernel mode) must not
* be fooled into using (reading or writing) addresses not available
* to the user mode process performing the system call.
*
* In pagedir.h you can find some supporting functions that will help
* you dermining if a logic address can be translated into a physical
* addrerss using the process pagetable. A single translation is
* costly. Work out a way to perform as few translations as
* possible.
*
* Recommended compilation command:
*
* gcc -Wall -Wextra -std=gnu99 -pedantic -m32 -g pagedir.o verify_adr.c
*/
#error Read comment above and then remove this line.
/* Verify all addresses from and including 'start' up to but excluding
* (start+length). */
bool verify_fix_length(void* start, int length)
{
// ADD YOUR CODE HERE
}
/* Verify all addresses from and including 'start' up to and including
* the address first containg a null-character ('\0'). (The way
* C-strings are stored.)
*/
bool verify_variable_length(char* start)
{
// ADD YOUR CODE HERE
}
/* Definition of test cases. */
struct test_case_t
{
void* start;
unsigned length;
};
#define TEST_CASE_COUNT 6
const struct test_case_t test_case[TEST_CASE_COUNT] =
{
{(void*)100, 100}, /* one full page */
{(void*)199, 102},
{(void*)101, 98},
{(void*)250, 190},
{(void*)250, 200},
{(void*)250, 210}
};
/* This main program will evalutate your solution. */
int main(int argc, char* argv[])
{
int i;
bool result;
if ( argc == 2 )
{
simulator_set_pagefault_time( atoi(argv[1]) );
}
thread_init();
/* Test the algorithm with a given intervall (a buffer). */
for (i = 0; i < TEST_CASE_COUNT; ++i)
{
start_evaluate_algorithm(test_case[i].start, test_case[i].length);
result = verify_fix_length(test_case[i].start, test_case[i].length);
evaluate(result);
end_evaluate_algorithm();
}
/* Test the algorithm with a C-string (start address with
* terminating null-character).
*/
for (i = 0; i < TEST_CASE_COUNT; ++i)
{
start_evaluate_algorithm(test_case[i].start, test_case[i].length);
result = verify_variable_length(test_case[i].start);
evaluate(result);
end_evaluate_algorithm();
}
return 0;
}
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