MERGECOMMIT: gcoap: Add file server RIOT-OS#14397

sys/Makefile

@@ -215,6 +215,9 @@ endif
 ifneq (,$(filter ztimer_xtimer_compat,$(USEMODULE)))
   FILTER += xtimer
 endif
+ifneq (,$(filter coapfileserver,$(USEMODULE)))
+    DIRS += net/application_layer/coapfileserver
+endif
 
 DIRS += $(dir $(wildcard $(addsuffix /Makefile, $(filter-out $(FILTER), $(USEMODULE)))))
 

sys/Makefile.dep

@@ -554,6 +554,10 @@ ifneq (,$(filter devfs,$(USEMODULE)))
   USEMODULE += vfs
 endif
 
+ifneq (,$(filter coapfileserver,$(USEMODULE)))
+  USEMODULE += vfs
+endif
+
 ifneq (,$(filter vfs_default,$(USEMODULE)))
   USEMODULE += vfs
   DEFAULT_MODULE += vfs_auto_mount

sys/include/net/coap.h

@@ -36,6 +36,7 @@ extern "C" {
  * @{
  */
 #define COAP_OPT_URI_HOST       (3)
+#define COAP_OPT_ETAG           (4)
 #define COAP_OPT_OBSERVE        (6)
 #define COAP_OPT_LOCATION_PATH  (8)
 #define COAP_OPT_URI_PATH       (11)

sys/include/net/coapfileserver.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2020 chrysn
+ *
+ * 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     net_coapfileserver
+ * @{
+ *
+ * @file
+ * @brief       Resource handler for the CoAP file system server
+ *
+ * @author      chrysn <chrysn@fsfe.org>
+ *
+ * @}
+ */
+
+#ifndef NET_COAPFILESERVER_H
+#define NET_COAPFILESERVER_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <net/nanocoap.h>
+
+/** File server starting point
+ *
+ * This struct needs to be present at the ctx of a coapfileserver_handler entry
+ * in a resource list.
+ *
+ */
+struct coapfileserver_entry {
+    /** Path in the VFS that should be served.
+     *
+     * This does not need a trailing slash. */
+    char *nameprefix;
+    /** Number of leading path components to ignore as they are the common prefix.
+     *
+     * If the file server is bound to the "/" resource, make this 0; if there
+     * is an entry
+     *
+     * ``{ "/files/sd", COAP_GET | COAP_MATCH_SUBTREE, coapfileserver_handler, files_sd }``
+     *
+     * then ``files_sd.strip_path`` needs to be 2.
+     *
+     * */
+    uint8_t strip_path;
+};
+
+/**
+ * File server handler
+ *
+ * Serve a directory from the VFS as a CoAP resource tree.
+ *
+ * @p ctx pointer to a @ref coapfileserver_entry
+ *
+ * @see net_coapfileserver
+ */
+ssize_t coapfileserver_handler(coap_pkt_t *pdu, uint8_t *buf, size_t len, void *ctx);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NET_COAPFILESERVER_H */
+
+/** @} */

sys/net/application_layer/coapfileserver/Makefile

@@ -0,0 +1,5 @@
+MODULE = coapfileserver
+
+SRC = coapfileserver.c
+
+include $(RIOTBASE)/Makefile.base