resource.h

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/*
 * resource.h -- generic resource handling
 *
 * Copyright (C) 2010,2011,2014,2015 Olaf Bergmann <bergmann@tzi.org>
 *
 * This file is part of the CoAP library libcoap. Please see README for terms
 * of use.
 */

#ifndef _COAP_RESOURCE_H_
#define _COAP_RESOURCE_H_

# include <assert.h>

#ifndef COAP_RESOURCE_CHECK_TIME

#define COAP_RESOURCE_CHECK_TIME 2
#endif /* COAP_RESOURCE_CHECK_TIME */

#ifdef COAP_RESOURCES_NOHASH
#  include "utlist.h"
#else
#  include "uthash.h"
#endif

#include "hashkey.h"
#include "async.h"
#include "str.h"
#include "pdu.h"
#include "net.h"
#include "subscribe.h"

typedef void (*coap_method_handler_t)
  (coap_context_t  *,
   struct coap_resource_t *,
   const coap_endpoint_t *,
   coap_address_t *,
   coap_pdu_t *,
   str * /* token */,
   coap_pdu_t * /* response */);

#define COAP_ATTR_FLAGS_RELEASE_NAME  0x1
#define COAP_ATTR_FLAGS_RELEASE_VALUE 0x2

typedef struct coap_attr_t {
  struct coap_attr_t *next;
  str name;
  str value;
  int flags;
} coap_attr_t;

#define COAP_RESOURCE_FLAGS_RELEASE_URI 0x1

#define COAP_RESOURCE_FLAGS_NOTIFY_NON  0x0

#define COAP_RESOURCE_FLAGS_NOTIFY_CON  0x2

typedef struct coap_resource_t {
  unsigned int dirty:1;          
  unsigned int partiallydirty:1; 
  unsigned int observable:1;     
  unsigned int cacheable:1;      
  coap_method_handler_t handler[4];

  coap_key_t key;                
#ifdef COAP_RESOURCES_NOHASH
  struct coap_resource_t *next;
#else
  UT_hash_handle hh;
#endif

  coap_attr_t *link_attr; 
  coap_subscription_t *subscribers;  
  str uri;
  int flags;

} coap_resource_t;

coap_resource_t *coap_resource_init(const unsigned char *uri,
                                    size_t len, int flags);


static inline void
coap_resource_set_mode(coap_resource_t *r, int mode) {
  r->flags = (r->flags & !COAP_RESOURCE_FLAGS_NOTIFY_CON) | mode;
}

void coap_add_resource(coap_context_t *context, coap_resource_t *resource);

int coap_delete_resource(coap_context_t *context, coap_key_t key);

void coap_delete_all_resources(coap_context_t *context);

coap_attr_t *coap_add_attr(coap_resource_t *resource,
                           const unsigned char *name,
                           size_t nlen,
                           const unsigned char *val,
                           size_t vlen,
                           int flags);

coap_attr_t *coap_find_attr(coap_resource_t *resource,
                            const unsigned char *name,
                            size_t nlen);

void coap_delete_attr(coap_attr_t *attr);

typedef unsigned int coap_print_status_t;

#define COAP_PRINT_STATUS_MASK  0xF0000000u
#define COAP_PRINT_OUTPUT_LENGTH(v) ((v) & ~COAP_PRINT_STATUS_MASK)
#define COAP_PRINT_STATUS_ERROR 0x80000000u
#define COAP_PRINT_STATUS_TRUNC 0x40000000u

coap_print_status_t coap_print_link(const coap_resource_t *resource,
                                    unsigned char *buf,
                                    size_t *len,
                                    size_t *offset);

static inline void
coap_register_handler(coap_resource_t *resource,
                      unsigned char method,
                      coap_method_handler_t handler) {
  assert(resource);
  assert(method > 0 && (size_t)(method-1) < sizeof(resource->handler)/sizeof(coap_method_handler_t));
  resource->handler[method-1] = handler;
}

coap_resource_t *coap_get_resource_from_key(coap_context_t *context,
                                            coap_key_t key);

void coap_hash_request_uri(const coap_pdu_t *request, coap_key_t key);

coap_subscription_t *coap_add_observer(coap_resource_t *resource,
                                       const coap_endpoint_t *local_interface,
                                       const coap_address_t *observer,
                                       const str *token);

coap_subscription_t *coap_find_observer(coap_resource_t *resource,
                                        const coap_address_t *peer,
                                        const str *token);

void coap_touch_observer(coap_context_t *context,
                         const coap_address_t *observer,
                         const str *token);

int coap_delete_observer(coap_resource_t *resource,
                         const coap_address_t *observer,
                         const str *token);

void coap_check_notify(coap_context_t *context);

#ifdef COAP_RESOURCES_NOHASH

#define RESOURCES_ADD(r, obj) \
  LL_PREPEND((r), (obj))

#define RESOURCES_DELETE(r, obj) \
  LL_DELETE((r), (obj))

#define RESOURCES_ITER(r,tmp) \
  coap_resource_t *tmp;       \
  LL_FOREACH((r), tmp)

#define RESOURCES_FIND(r, k, res) {                         \
    coap_resource_t *tmp;                                   \
    (res) = tmp = NULL;                                     \
    LL_FOREACH((r), tmp) {                                  \
      if (memcmp((k), tmp->key, sizeof(coap_key_t)) == 0) { \
        (res) = tmp;                                        \
        break;                                              \
      }                                                     \
    }                                                       \
  }
#else /* COAP_RESOURCES_NOHASH */

#define RESOURCES_ADD(r, obj) \
  HASH_ADD(hh, (r), key, sizeof(coap_key_t), (obj))

#define RESOURCES_DELETE(r, obj) \
  HASH_DELETE(hh, (r), (obj))

#define RESOURCES_ITER(r,tmp)  \
  coap_resource_t *tmp, *rtmp; \
  HASH_ITER(hh, (r), tmp, rtmp)

#define RESOURCES_FIND(r, k, res) {                     \
    HASH_FIND(hh, (r), (k), sizeof(coap_key_t), (res)); \
  }

#endif /* COAP_RESOURCES_NOHASH */

coap_print_status_t coap_print_wellknown(coap_context_t *,
                                         unsigned char *,
                                         size_t *, size_t,
                                         coap_opt_t *);

void coap_handle_failed_notify(coap_context_t *,
                               const coap_address_t *,
                               const str *);

#endif /* _COAP_RESOURCE_H_ */