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/*

* Copyright (C) 2008 Red Hat, Inc., Jason Baron <jbaron@redhat.com>

*

*/

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#define DYNAMIC_DEBUG_HASH_BITS 6

static const char *program;

static void usage(void)

{

printf("Usage: %s <djb2|r5> <modname>\n", program);

exit(1);

}

/* djb2 hashing algorithm by Dan Bernstein. From:

* http://www.cse.yorku.ca/~oz/hash.html

*/

unsigned int djb2_hash(char *str)

{

unsigned long hash = 5381;

int c;

c = *str;

while (c) {

hash = ((hash << 5) + hash) + c;

c = *++str;

}

return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));

}

unsigned int r5_hash(char *str)

{

unsigned long hash = 0;

int c;

c = *str;

while (c) {

hash = (hash + (c << 4) + (c >> 4)) * 11;

c = *++str;

}

return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));

}

int main(int argc, char *argv[])

{

program = argv[0];

if (argc != 3)

usage();

if (!strcmp(argv[1], "djb2"))

printf("%d\n", djb2_hash(argv[2]));

else if (!strcmp(argv[1], "r5"))

printf("%d\n", r5_hash(argv[2]));

else

usage();

exit(0);

}