haywire · boredzo · Jul 7 8000 , 2013 · Jul 7, 2013
diff --git a/src/haywire/http_response.c b/src/haywire/http_response.c
@@ -59,12 +59,17 @@ void hw_set_body(hw_http_response* response, char* body)
     resp->body = body;
 }
 
-char* itoa(int val, int base)
+char* itoa(unsigned int val, unsigned int base)
 {	
-	static char buf[32] = {0};
-	int i = 30;
+	enum {
+		buf_size = 33,
+		terminator_idx = buf_size - 1,
+		last_character_index = terminator_idx - 1
+	};
+	static char buf[buf_size] = {0};
+	int i = last_character_index;
 
-	for(; val && i ; --i, val /= base)
+	for(; val && (i >= 0) ; --i, val /= base)
     {
 
 		buf[i] = "0123456789abcdef"[val % base];

diff --git a/test/test_itoa/Makefile b/test/test_itoa/Makefile
@@ -0,0 +1,7 @@
+CFLAGS?=-std=c99 -I../../include -Wall -Wextra -Wno-unused-parameter -g
+
+test: test_itoa
+	./$^
+.PHONY: test
+
+test_itoa: test_itoa.o ../../src/haywire/http_response.o
diff --git a/test/test_itoa/test_itoa.c b/test/test_itoa/test_itoa.c
@@ -0,0 +1,32 @@
+#include <stdbool.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <assert.h>
+
+char* itoa(unsigned int val, unsigned int base);
+static bool test_itoa(unsigned int val, unsigned int base, const char *expected);
+
+#define INT_NIBBLES(h, g, f, e, d, c, b, a) (h##g##f##e##d##c##b##a)
+#define STR_NIBBLES(h, g, f, e, d, c, b, a) #h #g #f #e #d #c #b #a
+
+int main(int argc, char *argv[]) {
+	int status = EXIT_SUCCESS;
+	status |= !test_itoa(42, 10, "42");
+	//2**31
+	status |= !test_itoa(INT_NIBBLES(0b1000,0000,0000,0000,0000,0000,0000,0000), 2, STR_NIBBLES(1000,0000,0000,0000,0000,0000,0000,0000));
+
+	return status;
+}
+
+static bool test_itoa(unsigned int val, unsigned int base, const char *expected) {
+	const char *itoa_output = itoa(val, base);
+
+	if (strcmp(itoa_output, expected) != 0) {
+		fprintf(stderr, "itoa(%u, %d) failed: expected \"%s\"; got \"%s\"\n", val, base, expected, itoa_output);
+		return false;
+	}
+
+	return true;
+}