1 files changed, 155 insertions, 0 deletions
diff --git a/benchmark.c b/benchmark.c
new file mode 100644
index 0000000..1eb71fe
--- /dev/null
+++ b/benchmark.c
@@ -0,0 +1,155 @@
+#include "domain-lookup.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <time.h>
+
+static unsigned long range_rand(unsigned long min, unsigned long max)
+{
+	unsigned long base_random, range, remainder, bucket;
+
+	base_random = rand();
+	if (RAND_MAX == base_random)
+		return range_rand(min, max);
+	range = max - min;
+	remainder = RAND_MAX % range;
+	bucket = RAND_MAX / range;
+	if (base_random < RAND_MAX - remainder)
+		return min + base_random / bucket;
+	return range_rand(min, max);
+}
+
+
+static char* make_domain(char **dictionary, size_t size, size_t max_components)
+{
+	char *domain;
+	int i;
+	
+	domain = malloc(512);
+	domain[0] = 0;
+
+	/* strcat can overflow. I don't care. */
+	for (i = 0; i < range_rand(2, max_components + 1); ++i) {
+		if (i > 0)
+			strcat(domain, ".");
+		strcat(domain, dictionary[range_rand(0, size)]);
+	}
+
+	return domain;
+}
+
+
+static void* old_find_dlt(char *domain, char **domains, size_t domains_size)
+{
+	unsigned int namelen, matchlen, domainlen, i;
+	char *matchstart, *out;
+
+	namelen = strlen(domain);
+	matchlen = 0;
+	out = 0;
+	for (i = 0; i < domains_size; ++i) {
+		domainlen = strlen(domains[i]);
+		matchstart = domain + namelen - domainlen;
+		if (namelen >= domainlen &&
+		   (domainlen == 0 || namelen == domainlen || *(matchstart - 1) == '.' ) &&
+		    domainlen >= matchlen && !strcmp(matchstart, domains[i]))  {
+			matchlen = domainlen;
+			out = domains[i];
+		}
+	}
+	return out;
+}
+
+
+#define DICTIONARY_INITIAL_SIZE		250000
+#define DICTIONARY_TRUNCATED_SIZE	300
+#define INSERTED_DOMAINS_SIZE		100000
+#define QUERIED_DOMAINS_SIZE		100000
+#define INSERTED_DOMAINS_COMPONENTS	3
+#define QUERIED_DOMAINS_COMPONENTS	5
+#define DICTIONARY_PATH			"/usr/share/dict/words"
+
+int main()
+{
+	FILE *dictionary_file;
+	char **dictionary, **inserted_domains, **queried_domains;
+	void **verification_new, **verification_old;
+	char *word;
+	size_t dictionary_size, word_size, i;
+	struct domain_lookup_tree *head;
+	clock_t start, old_time, new_time;
+
+	srand(time(NULL) + 42);
+
+	printf("[+] Populating in-memory word list from " DICTIONARY_PATH ".\n");
+
+	dictionary = malloc(DICTIONARY_INITIAL_SIZE * sizeof(char *));
+	dictionary_file = fopen(DICTIONARY_PATH, "r");
+	if (!dictionary_file || !dictionary)
+		return 1;
+	for (dictionary_size = 0; dictionary_size < DICTIONARY_INITIAL_SIZE; ++dictionary_size) {
+		word_size = 256;
+		word = malloc(word_size);
+		if (!word)
+			return 1;
+		if (getline(&word, &word_size, dictionary_file) < 0)
+			break;
+		word_size = strlen(word);
+		if (word[word_size - 1] == '\n')
+			word[word_size - 1] = 0;
+		dictionary[dictionary_size] = word;
+	}
+	fclose(dictionary_file);
+
+	printf("[+] Truncating in-memory word list to %d random words.\n", DICTIONARY_TRUNCATED_SIZE);
+
+	for (i = 0; i < DICTIONARY_TRUNCATED_SIZE; ++i)
+		dictionary[i] = dictionary[range_rand(0, dictionary_size)];
+
+	printf("[+] Creating random lists of %d domains to insert and %d domains to query.\n", INSERTED_DOMAINS_SIZE, QUERIED_DOMAINS_SIZE);
+
+	inserted_domains = malloc(INSERTED_DOMAINS_SIZE * sizeof(char *));
+	queried_domains = malloc(QUERIED_DOMAINS_SIZE * sizeof(char *));
+	verification_new = malloc(QUERIED_DOMAINS_SIZE * sizeof(char *));
+	verification_old = malloc(QUERIED_DOMAINS_SIZE * sizeof(char *));
+	if (!inserted_domains || !queried_domains || !verification_new || !verification_old)
+		return 1;
+
+	for (i = 0; i < QUERIED_DOMAINS_SIZE; ++i)
+		queried_domains[i] = make_domain(dictionary, DICTIONARY_TRUNCATED_SIZE, QUERIED_DOMAINS_COMPONENTS);
+	for (i = 0; i < INSERTED_DOMAINS_SIZE; ++i)
+		inserted_domains[i] = make_domain(dictionary, DICTIONARY_TRUNCATED_SIZE, INSERTED_DOMAINS_COMPONENTS);
+
+	printf("[+] Populating domain lookup tree.\n");
+
+	head = init_dlt();
+	for (i = 0; i < INSERTED_DOMAINS_SIZE; ++i)
+		insert_dlt(head, inserted_domains[i], inserted_domains[i]);
+
+	printf("[+] Performing lookup benchmarks:\n");
+
+	start = clock();
+	for (i = 0; i < QUERIED_DOMAINS_SIZE; ++i)
+		verification_new[i] = find_dlt(head, queried_domains[i]);
+	new_time = clock() - start;
+	printf("    [*] New method took %.2f seconds.\n", (double)new_time / CLOCKS_PER_SEC);
+
+	start = clock();
+	for (i = 0; i < QUERIED_DOMAINS_SIZE; ++i)
+		verification_old[i] = old_find_dlt(queried_domains[i], inserted_domains, INSERTED_DOMAINS_SIZE);
+	old_time = clock() - start;
+	printf("    [*] Old method took %.2f seconds.\n", (double)old_time / CLOCKS_PER_SEC);
+
+	printf("    [*] The new method is %f times faster than the old method.\n", (double)old_time / (double)new_time);
+
+	printf("[+] Verifying that new and old methods produced identical results:\n");
+	for (i = 0; i < QUERIED_DOMAINS_SIZE; ++i) {
+		if (verification_old[i] != verification_new[i]) {
+			printf("    [!] New and old method produced different results!\n");
+			return 1;
+		}
+	}
+	printf("    [*] New and old methods produced the same results.\n");
+	return 0;
+}