gistfile1.c

#include <cipher.h>
#include <stdio.h>

int main()
{
	purple_ciphers_init();

	char key[] = "Jefe";
	char str[] = "what do ya want for nothing?";
	char *hash = (char *)malloc(100 * sizeof(char));
	memset(hash, 0, 100);

	PurpleCipherContext *hmac;
	hmac = purple_cipher_context_new_by_name("hmac", NULL);
	purple_cipher_context_set_option(hmac, "hash", "sha1");

	purple_cipher_context_set_key_with_len(hmac, (guchar *)key, strlen(key));
	purple_cipher_context_append(hmac, str, strlen(str));

	purple_cipher_context_digest_to_str(hmac, 100, hash, NULL);
	purple_cipher_context_destroy(hmac);

	printf("%s\n", hash);
}