sys/net/uhcp: use LOG_ functions

Using `gnrc_border_router` with `uhcp` is quite noisy.
uhcpc will regularly refresh the prefix and print a bunch of status messages.

Allow the user to tone it down by setting a higher `LOG_LEVEL`.
For this, convert calls to `printf()` and `puts()` to `LOG_xxx()`.

This requires a dummy header for `uhcpd`.

dist/tools/uhcpd/Makefile

@@ -11,7 +11,7 @@ RIOT_INCLUDE=$(RIOTBASE)/sys/include
 SRCS:=$(UHCP_DIR)/uhcp.c uhcpd.c
 HDRS:=$(RIOT_INCLUDE)/net/uhcp.h
 bin/uhcpd: $(SRCS) $(HDRS)
-	$(CC) $(CFLAGS) $(CFLAGS_EXTRA) -I$(RIOT_INCLUDE) $(SRCS) -o $@
+	$(CC) $(CFLAGS) $(CFLAGS_EXTRA) -I$(RIOT_INCLUDE) -I. $(SRCS) -o $@
 
 clean:
 	rm -f bin/uhcpd

dist/tools/uhcpd/log.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2020 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     core_util
+ * @{
+ *
+ * @file
+ * @brief       System logging dummy header
+ *
+ * This header offers a bunch of "LOG_*" functions that just use printf,
+ * without honouring a verbosity level.
+ *
+ * This is a dummy header for the purpose of sharing code that uses the
+ * LOG_xxx() functions between RIOT and host utilities without having to
+ * manually include all dependencies of the 'real' log module.
+ *
+ * @author      Benjamin Valentin <benjamin.valentin@ml-pa.com>
+ */
+
+#ifndef LOG_H
+#define LOG_H
+
+#include <stdio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @name Logging convenience defines
+ * @{
+ */
+#define LOG_ERROR(...) printf(__VA_ARGS__)
+#define LOG_WARNING(...) printf(__VA_ARGS__)
+#define LOG_INFO(...) printf(__VA_ARGS__)
+#define LOG_DEBUG(...) printf(__VA_ARGS__)
+/** @} */
+
+#endif /* LOG_H */
+/** @} */

sys/net/application_layer/uhcp/uhcp.c

@@ -6,29 +6,28 @@
  * directory for more details.
  */
 
-#include <stdio.h>
-
 #include <arpa/inet.h>
 #include <netinet/in.h>
 #include <string.h>
 
+#include "log.h"
 #include "net/uhcp.h"
 
 void uhcp_handle_udp(uint8_t *buf, size_t len, uint8_t *src, uint16_t port, uhcp_iface_t iface)
 {
     char addr_str[INET6_ADDRSTRLEN];
     inet_ntop(AF_INET6, src, addr_str, INET6_ADDRSTRLEN);
-    printf("got packet from %s port %u\n", addr_str, (unsigned)port);
+    LOG_INFO("got packet from %s port %u\n", addr_str, (unsigned)port);
 
     if (len < sizeof(uhcp_req_t)) {
-        puts("error: packet too small.");
+        LOG_ERROR("error: packet too small.\n");
         return;
     }
 
     uhcp_hdr_t *hdr = (uhcp_hdr_t *)buf;
 
     if (! (ntohl(hdr->uhcp_magic) == UHCP_MAGIC)) {
-        puts("error: wrong magic number.");
+        LOG_ERROR("error: wrong magic number.\n");
         return;
     }
 
@@ -37,14 +36,14 @@ void uhcp_handle_udp(uint8_t *buf, size_t len, uint8_t *src, uint16_t port, uhcp
     type = hdr->ver_type & 0xF;
 
     if (ver != UHCP_VER) {
-        puts("error: wrong protocol version.");
+        LOG_ERROR("error: wrong protocol version.\n");
     }
 
     switch(type) {
 #ifdef UHCP_SERVER
         case UHCP_REQ:
             if (len < sizeof(uhcp_req_t)) {
-                puts("error: request too small\n");
+                LOG_ERROR("error: request too small\n");
             }
             else {
                 uhcp_handle_req((uhcp_req_t*)hdr, src, port, iface);
@@ -58,7 +57,7 @@ void uhcp_handle_udp(uint8_t *buf, size_t len, uint8_t *src, uint16_t port, uhcp
                 if ((len < sizeof(uhcp_push_t))
                     || (len < (sizeof(uhcp_push_t) + (push->prefix_len >> 3)))
                    ) {
-                    puts("error: request too small\n");
+                    LOG_ERROR("error: request too small\n");
                 }
                 else {
                     uhcp_handle_push(push, src, port, iface);
@@ -67,7 +66,7 @@ void uhcp_handle_udp(uint8_t *buf, size_t len, uint8_t *src, uint16_t port, uhcp
             }
 #endif
         default:
-             puts("error: unexpected type\n");
+             LOG_ERROR("error: unexpected type\n");
     }
 }
 
@@ -87,7 +86,7 @@ void uhcp_handle_req(uhcp_req_t *req, uint8_t *src, uint16_t port, uhcp_iface_t
 
     int res = udp_sendto(packet, sizeof(packet), src, port, iface);
     if (res == -1) {
-        printf("uhcp_handle_req(): udp_sendto() res=%i\n", res);
+        LOG_ERROR("uhcp_handle_req(): udp_sendto() res=%i\n", res);
     }
 }
 #endif /* UHCP_SERVER */
@@ -105,7 +104,7 @@ void uhcp_handle_push(uhcp_push_t *req, uint8_t *src, uint16_t port, uhcp_iface_
 
     inet_ntop(AF_INET6, prefix, prefix_str, INET6_ADDRSTRLEN);
 
-    printf("uhcp: push from %s:%u prefix=%s/%u\n", addr_str, (unsigned)port, prefix_str, req->prefix_len);
+    LOG_INFO("uhcp: push from %s:%u prefix=%s/%u\n", addr_str, (unsigned)port, prefix_str, req->prefix_len);
     uhcp_handle_prefix(prefix, req->prefix_len, 0xFFFF, src, iface);
 }
 #endif

sys/net/application_layer/uhcp/uhcpc.c

@@ -7,8 +7,8 @@
  */
 
 #include <arpa/inet.h>
-#include <stdio.h>
 
+#include "log.h"
 #include "net/af.h"
 #include "net/sock/udp.h"
 #include "net/uhcp.h"
@@ -39,14 +39,14 @@ void uhcp_client(uhcp_iface_t iface)
     /* create listening socket */
     int res = sock_udp_create(&sock, &local, NULL, 0);
     if (res < 0) {
-        puts("uhcp_client(): cannot create listening socket");
+        LOG_ERROR("uhcp_client(): cannot create listening socket\n");
         return;
     }
 
     uint8_t buf[sizeof(uhcp_push_t) + 16];
 
     while(1) {
-        puts("uhcp_client(): sending REQ...");
+        LOG_INFO("uhcp_client(): sending REQ...\n");
         sock_udp_send(&sock, &req, sizeof(uhcp_req_t), &req_target);
         res = sock_udp_recv(&sock, buf, sizeof(buf), 10U*US_PER_SEC, &remote);
         if (res > 0) {
@@ -54,7 +54,7 @@ void uhcp_client(uhcp_iface_t iface)
             xtimer_sleep(60);
         }
         else {
-            puts("uhcp_client(): no reply received");
+            LOG_ERROR("uhcp_client(): no reply received\n");
         }
     }
 }

sys/net/gnrc/application_layer/uhcpc/gnrc_uhcpc.c

@@ -146,8 +146,8 @@ void uhcp_handle_prefix(uint8_t *prefix, uint8_t prefix_len, uint16_t lifetime,
     if ((_prefix_len == prefix_len) &&
         (ipv6_addr_match_prefix(&_prefix,
                                 (ipv6_addr_t *)prefix) >= prefix_len)) {
-        LOG_WARNING("gnrc_uhcpc: uhcp_handle_prefix(): got same prefix "
-                    "again\n");
+        LOG_INFO("gnrc_uhcpc: uhcp_handle_prefix(): got same prefix "
+                 "again\n");
 #ifdef MODULE_GNRC_SIXLOWPAN_CTX
         if (gnrc_netif_is_6ln(gnrc_netif_get_by_pid(gnrc_wireless_interface))) {
             /* always update 6LoWPAN compression context so it does not time