#include "kernel/types.h"
#include "kernel/stat.h"
#include "user/user.h"

void
test_dirtypages()
{
    printf("dirtypages test starting\n");
    
    // Allocate some pages
    char *buf = malloc(32 * 4096);  // 32 pages
    if(buf == 0) {
        printf("malloc failed\n");
        exit(1);
    }
    
    // Clear dirty bits first by calling dirtypages
    unsigned int dbits;
    if (dirtypages(buf, 32, &dbits) < 0) {
        printf("dirtypages failed\n");
        exit(1);
    }
    printf("Initial dirty bits cleared: 0x%x\n", dbits);
    
    // Write to some pages to make them dirty
    buf[0] = 1;         // Page 0
    buf[4096 * 5] = 1;  // Page 5
    buf[4096 * 10] = 1; // Page 10
    
    // Check dirty pages
    if (dirtypages(buf, 32, &dbits) < 0) {
        printf("dirtypages failed\n");
        exit(1);
    }
    
    printf("Dirty bits after writes: 0x%x\n", dbits);
    
    // Check if the expected pages are marked as dirty
    if (dbits & (1 << 0))
        printf("Page 0 is dirty (expected)\n");
    if (dbits & (1 << 5))
        printf("Page 5 is dirty (expected)\n");
    if (dbits & (1 << 10))
        printf("Page 10 is dirty (expected)\n");
    
    // Check again - dirty bits should be cleared now
    if (dirtypages(buf, 32, &dbits) < 0) {
        printf("dirtypages failed\n");
        exit(1);
    }
    printf("Dirty bits after clearing: 0x%x (should be 0)\n", dbits);
    
    free(buf);
    printf("dirtypages test: OK\n");
}

int
main(int argc, char *argv[])
{
    test_dirtypages();
    exit(0);
}