resource/csdk/stack/src/ocobserve.c

   1 //******************************************************************
   2 //
   3 // Copyright 2014 Intel Mobile Communications GmbH All Rights Reserved.
   4 //
   5 //-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
   6 //
   7 // Licensed under the Apache License, Version 2.0 (the "License");
   8 // you may not use this file except in compliance with the License.
   9 // You may obtain a copy of the License at
  10 //
  11 //      http://www.apache.org/licenses/LICENSE-2.0
  12 //
  13 // Unless required by applicable law or agreed to in writing, software
  14 // distributed under the License is distributed on an "AS IS" BASIS,
  15 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16 // See the License for the specific language governing permissions and
  17 // limitations under the License.
  18 //
  19 //-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
  20
  21 #include <string.h>
  22 #include "ocstack.h"
  23 #include "ocstackconfig.h"
  24 #include "ocstackinternal.h"
  25 #include "ocobserve.h"
  26 #include "ocresourcehandler.h"
  27 #include "occoap.h"
  28 #include "utlist.h"
  29 #include "debug.h"
  30 #include "ocrandom.h"
  31 #include "ocmalloc.h"
  32 #include "ocserverrequest.h"
  33
  34 // Module Name
  35 #define MOD_NAME PCF("ocobserve")
  36
  37 #define TAG  PCF("OCStackObserve")
  38
  39 #define VERIFY_NON_NULL(arg) { if (!arg) {OC_LOG(FATAL, TAG, #arg " is NULL"); goto exit;} }
  40
  41 static struct ResourceObserver * serverObsList = NULL;
  42
  43 // send notifications based on the qos of the request
  44 // The qos passed as a parameter overrides what the client requested
  45 // If we want the client preference taking high priority make:
  46 // qos = resourceObserver->qos;
  47 OCQualityOfService DetermineObserverQoS(OCMethod method, ResourceObserver * resourceObserver,
  48         OCQualityOfService appQoS)
  49 {
  50     OCQualityOfService decidedQoS = appQoS;
  51     if(appQoS == OC_NA_QOS)
  52     {
  53         decidedQoS = resourceObserver->qos;
  54     }
  55
  56     if(appQoS != OC_HIGH_QOS)
  57     {
  58         OC_LOG_V(INFO, TAG, "Current NON count for this observer is %d",
  59                 resourceObserver->lowQosCount);
  60         #ifdef WITH_PRESENCE
  61         if((resourceObserver->forceHighQos \
  62                 || resourceObserver->lowQosCount >= MAX_OBSERVER_NON_COUNT) \
  63                 && method != OC_REST_PRESENCE)
  64         #else
  65         if(resourceObserver->forceHighQos \
  66                 || resourceObserver->lowQosCount >= MAX_OBSERVER_NON_COUNT)
  67         #endif
  68             {
  69             resourceObserver->lowQosCount = 0;
  70             // at some point we have to to send CON to check on the
  71             // availability of observer
  72             OC_LOG(INFO, TAG, PCF("This time we are sending the  notification as High qos"));
  73             decidedQoS = OC_HIGH_QOS;
  74             }
  75         else
  76         {
  77             (resourceObserver->lowQosCount)++;
  78         }
  79     }
  80     return decidedQoS;
  81 }
  82
  83 #ifdef WITH_PRESENCE
  84 OCStackResult SendAllObserverNotification (OCMethod method, OCResource *resPtr, uint32_t maxAge,
  85         OCResourceType *resourceType, OCQualityOfService qos)
  86 #else
  87 OCStackResult SendAllObserverNotification (OCMethod method, OCResource *resPtr, uint32_t maxAge,
  88         OCQualityOfService qos)
  89 #endif
  90 {
  91     OC_LOG(INFO, TAG, PCF("Entering SendObserverNotification"));
  92     OCStackResult result = OC_STACK_ERROR;
  93     ResourceObserver * resourceObserver = serverObsList;
  94     uint8_t numObs = 0;
  95     OCServerRequest * request = NULL;
  96     OCEntityHandlerRequest ehRequest = {0};
  97     OCEntityHandlerResult ehResult = OC_EH_ERROR;
  98
  99     // Find clients that are observing this resource
 100     while (resourceObserver)
 101     {
 102         if (resourceObserver->resource == resPtr)
 103         {
 104             numObs++;
 105             #ifdef WITH_PRESENCE
 106             if(method != OC_REST_PRESENCE)
 107             {
 108             #endif
 109                 qos = DetermineObserverQoS(method, resourceObserver, qos);
 110                 result = AddServerRequest(&request, 0, 0, 0, 1, OC_REST_GET,
 111                         0, resPtr->sequenceNum, qos, resourceObserver->query,
 112                         NULL, NULL,
 113                         &resourceObserver->token, resourceObserver->addr,
 114                         resourceObserver->resUri, 0);
 115                 request->observeResult = OC_STACK_OK;
 116                 if(request && result == OC_STACK_OK)
 117                 {
 118                     result = FormOCEntityHandlerRequest(&ehRequest, (OCRequestHandle) request,
 119                                 request->method, (OCResourceHandle) resPtr, request->query,
 120                                 request->reqJSONPayload, request->numRcvdVendorSpecificHeaderOptions,
 121                                 request->rcvdVendorSpecificHeaderOptions, OC_OBSERVE_NO_OPTION, 0);
 122                     if(result == OC_STACK_OK)
 123                     {
 124                         ehResult = resPtr->entityHandler(OC_REQUEST_FLAG, &ehRequest);
 125                         if(ehResult == OC_EH_ERROR)
 126                         {
 127                             FindAndDeleteServerRequest(request);
 128                         }
 129                     }
 130                 }
 131             #ifdef WITH_PRESENCE
 132             }
 133             else
 134             {
 135                 OCEntityHandlerResponse ehResponse = {0};
 136                 unsigned char presenceResBuf[MAX_RESPONSE_LENGTH] = {0};
 137                 //This is effectively the implementation for the presence entity handler.
 138                 OC_LOG(DEBUG, TAG, PCF("This notification is for Presence"));
 139                 result = AddServerRequest(&request, 0, 0, 0, 1, OC_REST_GET,
 140                         0, OC_OBSERVE_NO_OPTION, OC_LOW_QOS,
 141                         NULL, NULL, NULL, &resourceObserver->token,
 142                         resourceObserver->addr, resourceObserver->resUri, 0);
 143                 if(result == OC_STACK_OK)
 144                 {
 145                     // we create the payload here
 146                     if(resourceType && resourceType->resourcetypename)
 147                     {
 148                         snprintf((char *)presenceResBuf, sizeof(presenceResBuf), "%u:%u:%s",
 149                                 resPtr->sequenceNum, maxAge, resourceType->resourcetypename);
 150                     }
 151                     else
 152                     {
 153                         snprintf((char *)presenceResBuf, sizeof(presenceResBuf), "%u:%u",
 154                                 resPtr->sequenceNum, maxAge);
 155                     }
 156                     ehResponse.ehResult = OC_EH_OK;
 157                     ehResponse.payload = presenceResBuf;
 158                     ehResponse.payloadSize = strlen((const char *)presenceResBuf) + 1;
 159                     ehResponse.persistentBufferFlag = 0;
 160                     ehResponse.requestHandle = (OCRequestHandle) request;
 161                     ehResponse.resourceHandle = (OCResourceHandle) resPtr;
 162                     strcpy((char *)ehResponse.resourceUri, (const char *)resourceObserver->resUri);
 163                     result = OCDoResponse(&ehResponse);
 164                 }
 165             }
 166             #endif
 167         }
 168         resourceObserver = resourceObserver->next;
 169     }
 170     if (numObs == 0)
 171     {
 172         OC_LOG(INFO, TAG, PCF("Resource has no observers"));
 173         result = OC_STACK_NO_OBSERVERS;
 174     }
 175     return result;
 176 }
 177
 178 OCStackResult SendListObserverNotification (OCResource * resource,
 179         OCObservationId  *obsIdList, uint8_t numberOfIds,
 180         unsigned char *notificationJSONPayload, uint32_t maxAge,
 181         OCQualityOfService qos)
 182 {
 183     uint8_t numIds = numberOfIds;
 184     ResourceObserver *observation = NULL;
 185     uint8_t numSentNotification = 0;
 186     OCServerRequest * request = NULL;
 187     OCStackResult result = OC_STACK_ERROR;
 188     OCEntityHandlerResponse ehResponse = {0};
 189
 190     OC_LOG(INFO, TAG, PCF("Entering SendListObserverNotification"));
 191     while(numIds)
 192     {
 193         OC_LOG_V(INFO, TAG, "Need to notify observation id %d", *obsIdList);
 194         observation = NULL;
 195         observation = GetObserverUsingId (*obsIdList);
 196         if(observation)
 197         {
 198             // Found observation - verify if it matches the resource handle
 199             if (observation->resource == resource)
 200             {
 201                 qos = DetermineObserverQoS(OC_REST_GET, observation, qos);
 202
 203                 result = AddServerRequest(&request, 0, 0, 0, 1, OC_REST_GET,
 204                         0, resource->sequenceNum, qos, observation->query,
 205                         NULL, NULL, &observation->token,
 206                         observation->addr, observation->resUri, 0);
 207                 request->observeResult = OC_STACK_OK;
 208                 if(request && result == OC_STACK_OK)
 209                 {
 210                     memset(&ehResponse, 0, sizeof(OCEntityHandlerResponse));
 211                     ehResponse.ehResult = OC_EH_OK;
 212                     ehResponse.payload = (unsigned char *) OCMalloc(MAX_RESPONSE_LENGTH);
 213                     if(!ehResponse.payload)
 214                     {
 215                         FindAndDeleteServerRequest(request);
 216                         continue;
 217                     }
 218                     strcpy((char *)ehResponse.payload, (const char *)notificationJSONPayload);
 219                     ehResponse.payloadSize = strlen((const char *)ehResponse.payload) + 1;
 220                     ehResponse.persistentBufferFlag = 0;
 221                     ehResponse.requestHandle = (OCRequestHandle) request;
 222                     ehResponse.resourceHandle = (OCResourceHandle) resource;
 223                     result = OCDoResponse(&ehResponse);
 224                     if(result == OC_STACK_OK)
 225                     {
 226                         OCFree(ehResponse.payload);
 227                         FindAndDeleteServerRequest(request);
 228                     }
 229                 }
 230                 else
 231                 {
 232                     FindAndDeleteServerRequest(request);
 233                 }
 234
 235                 numSentNotification++;
 236             }
 237         }
 238         obsIdList++;
 239         numIds--;
 240     }
 241     if(numSentNotification == numberOfIds)
 242     {
 243         return OC_STACK_OK;
 244     }
 245     else if(numSentNotification == 0)
 246     {
 247         return OC_STACK_NO_OBSERVERS;
 248     }
 249     else
 250     {
 251         //TODO: we need to signal that not every one in the
 252         // list got an update, should we also indicate who did not receive on?
 253         return OC_STACK_OK;
 254     }
 255 }
 256
 257 OCStackResult GenerateObserverId (OCObservationId *observationId)
 258 {
 259     ResourceObserver *resObs = NULL;
 260
 261     OC_LOG(INFO, TAG, PCF("Entering GenerateObserverId"));
 262     VERIFY_NON_NULL (observationId);
 263
 264     do
 265     {
 266         *observationId = OCGetRandomByte();
 267         // Check if observation Id already exists
 268         resObs = GetObserverUsingId (*observationId);
 269     } while (NULL != resObs);
 270
 271     OC_LOG_V(INFO, TAG, "Observation ID is %u", *observationId);
 272
 273     return OC_STACK_OK;
 274 exit:
 275     return OC_STACK_ERROR;
 276 }
 277
 278 OCStackResult AddObserver (const char         *resUri,
 279                            const char         *query,
 280                            OCObservationId    obsId,
 281                            OCCoAPToken        *token,
 282                            OCDevAddr          *addr,
 283                            OCResource         *resHandle,
 284                            OCQualityOfService qos)
 285 {
 286     ResourceObserver *obsNode = NULL;
 287
 288     obsNode = (ResourceObserver *) OCCalloc(1, sizeof(ResourceObserver));
 289     if (obsNode)
 290     {
 291         obsNode->observeId = obsId;
 292
 293         obsNode->resUri = (unsigned char *)OCMalloc(strlen(resUri)+1);
 294         VERIFY_NON_NULL (obsNode->resUri);
 295         memcpy (obsNode->resUri, resUri, strlen(resUri)+1);
 296
 297         obsNode->qos = qos;
 298         if(query)
 299         {
 300             obsNode->query = (unsigned char *)OCMalloc(strlen(query)+1);
 301             VERIFY_NON_NULL (obsNode->query);
 302             memcpy (obsNode->query, query, strlen(query)+1);
 303         }
 304
 305         obsNode->token.tokenLength = token->tokenLength;
 306         memcpy (obsNode->token.token, token->token, token->tokenLength);
 307
 308         obsNode->addr = (OCDevAddr *)OCMalloc(sizeof(OCDevAddr));
 309         VERIFY_NON_NULL (obsNode->addr);
 310         memcpy (obsNode->addr, addr, sizeof(OCDevAddr));
 311
 312         obsNode->resource = resHandle;
 313
 314         LL_APPEND (serverObsList, obsNode);
 315         return OC_STACK_OK;
 316     }
 317
 318 exit:
 319     if (obsNode)
 320     {
 321         OCFree(obsNode->resUri);
 322         OCFree(obsNode->query);
 323         OCFree(obsNode->addr);
 324         OCFree(obsNode);
 325     }
 326     return OC_STACK_NO_MEMORY;
 327 }
 328
 329 ResourceObserver* GetObserverUsingId (const OCObservationId observeId)
 330 {
 331     ResourceObserver *out = NULL;
 332
 333     if (observeId)
 334     {
 335         LL_FOREACH (serverObsList, out)
 336         {
 337             if (out->observeId == observeId)
 338             {
 339                 return out;
 340             }
 341         }
 342     }
 343     OC_LOG(INFO, TAG, PCF("Observer node not found!!"));
 344     return NULL;
 345 }
 346
 347 ResourceObserver* GetObserverUsingToken (const OCCoAPToken * token)
 348 {
 349     ResourceObserver *out = NULL;
 350
 351     if(token)
 352     {
 353         LL_FOREACH (serverObsList, out)
 354         {
 355             OC_LOG(INFO, TAG,PCF("comparing tokens"));
 356             OC_LOG_BUFFER(INFO, TAG, token->token, token->tokenLength);
 357             OC_LOG_BUFFER(INFO, TAG, out->token.token, out->token.tokenLength);
 358             if((out->token.tokenLength == token->tokenLength) &&
 359                (memcmp(out->token.token, token->token, token->tokenLength) == 0))
 360             {
 361                 return out;
 362             }
 363         }
 364     }
 365     OC_LOG(INFO, TAG, PCF("Observer node not found!!"));
 366     return NULL;
 367 }
 368
 369 OCStackResult DeleteObserverUsingToken (OCCoAPToken * token)
 370 {
 371     ResourceObserver *obsNode = NULL;
 372
 373     obsNode = GetObserverUsingToken (token);
 374     if (obsNode)
 375     {
 376         OC_LOG_V(INFO, TAG, PCF("deleting tokens"));
 377         OC_LOG_BUFFER(INFO, TAG, obsNode->token.token, obsNode->token.tokenLength);
 378         LL_DELETE (serverObsList, obsNode);
 379         OCFree(obsNode->resUri);
 380         OCFree(obsNode->query);
 381         OCFree(obsNode->addr);
 382         OCFree(obsNode);
 383     }
 384     // it is ok if we did not find the observer...
 385     return OC_STACK_OK;
 386 }
 387
 388 void DeleteObserverList()
 389 {
 390     ResourceObserver *out = NULL;
 391     ResourceObserver *tmp = NULL;
 392     LL_FOREACH_SAFE (serverObsList, out, tmp)
 393     {
 394         DeleteObserverUsingToken (&(out->token));
 395     }
 396     serverObsList = NULL;
 397 }