#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/fcntl.h>

#include "pagemap.h"

static void add_index(unsigned long index)
{
	static unsigned long offset, len;

	if (index == offset + len)
		len++;
	else {
		if (len)
			printf("%10lu %8lu %8luKB\n", offset, len, pages2kb(len));
		offset = index;
		len = 1;
	}
}

static void usage(const char *prog)
{
	printf("Usage: %s page_flags\n", prog);
}

int main(int argc, char *argv[])
{
	static char kpageflags_name[] = "/proc/kpageflags";
	unsigned long match_flags, match_exact;
	unsigned long i;
	char *p;
	int fd;

	if (argc < 2) {
		usage(argv[0]);
		exit(1);
	}

	match_exact = 0;
	p = argv[1];
	if (p[0] == '=') {
		match_exact = 1;
		p++;
	}
	match_flags = strtol(p, 0, 16);

	fd = open(kpageflags_name, O_RDONLY);
	if (fd < 0) {
		perror(kpageflags_name);
		exit(1);
	}

	nr_pages = read(fd, kpageflags, sizeof(kpageflags));
	if (nr_pages <= 0) {
		perror(kpageflags_name);
		exit(2);
	}
	if (nr_pages % KPF_BYTES != 0) {
		fprintf(stderr, "%s: partial read: %lu bytes\n",
				argv[0], nr_pages);
		exit(3);
	}
	nr_pages = nr_pages / KPF_BYTES;

	printf("    offset      len         KB\n");
	for (i = 0; i < nr_pages; i++) {
		if (!match_exact && ((kpageflags[i] & match_flags) == match_flags) ||
		    (match_exact && kpageflags[i] == match_flags))
			add_index(i);
	}
	add_index(0);

	return 0;
}