5 files changed, 16 insertions, 14 deletions
diff --git a/client.c b/client.c
index 0f8bde1..7c0eb71 100644
--- a/client.c
+++ b/client.c
@@ -52,7 +52,7 @@ int main(void) {
 		if (FD_ISSET(d_fd, &inset) && icmpd_peek(d)) {
 			struct icmpd_received msg = icmpd_recv(d);
 			printf("Recv: %zu\n", msg.length);
-			xxd(msg.data, msg.length);
+			xxd(stdout, msg.data, msg.length);
 		}
 	}
 }
diff --git a/icmp.h b/icmp.h
index eed1714..c242207 100644
--- a/icmp.h
+++ b/icmp.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <stddef.h>
 #include <stdint.h>
 
 
diff --git a/server.c b/server.c
index b99e4ea..2ace5b5 100644
--- a/server.c
+++ b/server.c
@@ -53,7 +53,7 @@ int main(void) {
 		if (FD_ISSET(server_fd, &inset) && icmpd_peek(server)) {
 			struct icmpd_received msg = icmpd_recv(server);
 			printf("Server recv: %zu\n", msg.length);
-			xxd(msg.data, msg.length);
+			xxd(stdout, msg.data, msg.length);
 
 			if (conn) {
 				printf("Message received while already connected\n");
@@ -76,7 +76,7 @@ int main(void) {
 		if (conn && FD_ISSET(conn_fd, &inset) && icmpd_peek(conn)) {
 			struct icmpd_received msg = icmpd_recv(conn);
 			printf("Connection recv: %zu\n", msg.length);
-			xxd(msg.data, msg.length);
+			xxd(stdout, msg.data, msg.length);
 			free(msg.data);
 		}
 	}
diff --git a/util.c b/util.c
index 9c7e1a3..7bd9025 100644
--- a/util.c
+++ b/util.c
@@ -13,27 +13,27 @@ int uniqid(void) {
 	return i++;
 }
 
-void xxd(const void *buf_, size_t length) {
+void xxd(FILE *stream, const void *buf_, size_t length) {
 	unsigned char *buf = (unsigned char*)buf_;
 
 	for (size_t cursor = 0; cursor < length;) {
-		printf("%08zx:", cursor);
+		fprintf(stream, "%08zx:", cursor);
 
 		for (int i = 0; i < 16; i++) {
-			if (i % 2 == 0) printf(" ");
-			if (i % 8 == 0) printf(" ");
-			if (cursor + i < length) printf("%02x", (unsigned)buf[cursor + i]);
-			else printf("  ");
+			if (i % 2 == 0) fprintf(stream, " ");
+			if (i % 8 == 0) fprintf(stream, " ");
+			if (cursor + i < length) fprintf(stream, "%02x", (unsigned)buf[cursor + i]);
+			else fprintf(stream, "  ");
 		}
 
-		printf("  |");
+		fprintf(stream, "  |");
 
 		for (int i = 0; i < 16 && cursor + i < length; i++) {
-			if (isprint(buf[cursor + i])) printf("%c", buf[cursor + i]);
-			else printf(".");
+			if (isprint(buf[cursor + i])) fprintf(stream, "%c", buf[cursor + i]);
+			else fprintf(stream, ".");
 		}
 
-		printf("|\n");
+		fprintf(stream, "|\n");
 
 		cursor += 16;
 	}
diff --git a/util.h b/util.h
index 88ad996..898f10e 100644
--- a/util.h
+++ b/util.h
@@ -1,12 +1,13 @@
 #pragma once
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
 #include <unistd.h>
 
 
 int uniqid(void);
-void xxd(const void *buf, size_t length);
+void xxd(FILE *stream, const void *buf, size_t length);
 ssize_t readall(int fd, void *data, size_t length);
 ssize_t writeall(int fd, const void *data, size_t length);
 int maxi(int a, int b);