ucs2-lib/src/ucs_scheduler.c

   1 /*------------------------------------------------------------------------------------------------*/
   2 /* UNICENS V2.1.0-3491                                                                            */
   3 /* Copyright (c) 2017 Microchip Technology Germany II GmbH & Co. KG.                              */
   4 /*                                                                                                */
   5 /* This program is free software: you can redistribute it and/or modify                           */
   6 /* it under the terms of the GNU General Public License as published by                           */
   7 /* the Free Software Foundation, either version 2 of the License, or                              */
   8 /* (at your option) any later version.                                                            */
   9 /*                                                                                                */
  10 /* This program is distributed in the hope that it will be useful,                                */
  11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of                                 */
  12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                                  */
  13 /* GNU General Public License for more details.                                                   */
  14 /*                                                                                                */
  15 /* You should have received a copy of the GNU General Public License                              */
  16 /* along with this program.  If not, see <http://www.gnu.org/licenses/>.                          */
  17 /*                                                                                                */
  18 /* You may also obtain this software under a propriety license from Microchip.                    */
  19 /* Please contact Microchip for further information.                                              */
  20 /*------------------------------------------------------------------------------------------------*/
  21
  22 /*!
  23  * \file
  24  * \brief Implementation of the scheduler module. The module consists of the two classes
  25  *        CScheduler and CService.
  26  *
  27  * \cond UCS_INTERNAL_DOC
  28  * \addtogroup G_SCHEDULER
  29  * @{
  30  */
  31
  32 /*------------------------------------------------------------------------------------------------*/
  33 /* Includes                                                                                       */
  34 /*------------------------------------------------------------------------------------------------*/
  35 #include "ucs_scheduler.h"
  36 #include "ucs_misc.h"
  37
  38 /*------------------------------------------------------------------------------------------------*/
  39 /* Constants                                                                                      */
  40 /*------------------------------------------------------------------------------------------------*/
  41 const Srv_Event_t SRV_EMPTY_EVENT_MASK = (Srv_Event_t)0x00000000;   /*!< \brief Empty event mask */
  42
  43 /*------------------------------------------------------------------------------------------------*/
  44 /* Internal prototypes                                                                            */
  45 /*------------------------------------------------------------------------------------------------*/
  46 static bool Scd_SearchSlot(void *current_prio_ptr, void *new_prio_ptr);
  47
  48 /*------------------------------------------------------------------------------------------------*/
  49 /* Implementation of class CScheduler                                                             */
  50 /*------------------------------------------------------------------------------------------------*/
  51 /*! \brief Constructor of the scheduler class.
  52  *  \param self        Instance pointer
  53  *  \param init_ptr    Reference to the initialization data
  54  *  \param ucs_user_ptr User reference that needs to be passed in every callback function
  55  */
  56 void Scd_Ctor(CScheduler *self, Scd_InitData_t *init_ptr, void * ucs_user_ptr)
  57 {
  58     MISC_MEM_SET(self, 0, sizeof(*self));
  59     self->ucs_user_ptr = ucs_user_ptr;
  60     Dl_Ctor(&self->srv_list, ucs_user_ptr);
  61     Ssub_Ctor(&self->service_request_subject, ucs_user_ptr);
  62     (void)Ssub_AddObserver(&self->service_request_subject,
  63                            init_ptr->service_request_obs_ptr);
  64     self->scd_srv_is_running = false;
  65 }
  66
  67 /*! \brief  Add the given service to the scheduler. All services are arranged in priority order.
  68  *          A service with a higher priority will execute before a service with a lower priority.
  69  *  \param  self       Instance pointer
  70  *  \param  srv_ptr    Reference of the service which shall be added
  71  *  \return SCD_OK: Service added
  72  *  \return SCD_SRV_ALREADY_LISTED: Services already listed
  73  */
  74 Scd_Ret_t Scd_AddService(CScheduler *self, CService *srv_ptr)
  75 {
  76     Scd_Ret_t ret_val;
  77
  78     /* Check that service is not already part of scheduler */
  79     if(Dl_IsNodeInList(&self->srv_list, &srv_ptr->list_node) == false)
  80     {
  81         /* Search slot where the service must be inserted depending on the priority value.  */
  82         CDlNode *result_ptr = Dl_Foreach(&self->srv_list, &Scd_SearchSlot, &srv_ptr->priority);
  83
  84         if(result_ptr != NULL)   /* Slot found? */
  85         {
  86             Dl_InsertBefore(&self->srv_list, result_ptr, &srv_ptr->list_node);
  87         }
  88         else                    /* No slot found -> Insert as last node */
  89         {
  90             Dl_InsertTail(&self->srv_list, &srv_ptr->list_node);
  91         }
  92         /* Create back link service -> scheduler */
  93         srv_ptr->scd_ptr = self;
  94         Dln_SetData(&srv_ptr->list_node, &srv_ptr->priority);
  95         ret_val = SCD_OK;
  96     }
  97     else    /* Service is already part of schedulers list */
  98     {
  99         ret_val = SCD_SRV_ALREADY_LISTED;
 100     }
 101
 102     return ret_val;
 103 }
 104
 105 /*! \brief  Remove the given service from the schedulers list.
 106  *  \param  self       Instance pointer
 107  *  \param  srv_ptr    Reference of the service which shall be removed
 108  *  \return SCD_OK: Service removed
 109  *  \return SCD_UNKNOWN_SRV: Unknown service can not be removed
 110  */
 111 Scd_Ret_t Scd_RemoveService(CScheduler *self, CService *srv_ptr)
 112 {
 113     Scd_Ret_t ret_val = SCD_OK;
 114
 115     /* Error occurred? */
 116     if(Dl_Remove(&self->srv_list, &srv_ptr->list_node) == DL_UNKNOWN_NODE)
 117     {
 118         ret_val = SCD_UNKNOWN_SRV;
 119     }
 120
 121     return ret_val;
 122 }
 123
 124 /*! \brief Service function of the scheduler module.
 125  *  \param self   Instance pointer
 126  */
 127 void Scd_Service(CScheduler *self)
 128 {
 129     CService *current_srv_ptr = (CService *)(void*)self->srv_list.head;
 130
 131     /* Scheduler service is running. Important for event handling */
 132     self->scd_srv_is_running = true;
 133
 134     while(current_srv_ptr != NULL)   /* Process registered services */
 135     {
 136         if(current_srv_ptr->service_fptr != NULL)
 137         {
 138             /* Are events pending for the current service */
 139             if(current_srv_ptr->event_mask != SRV_EMPTY_EVENT_MASK)
 140             {
 141                 /* Execute service callback function */
 142                 current_srv_ptr->service_fptr(current_srv_ptr->instance_ptr);
 143                 /* Was the current service removed from the schedulers list? */
 144                 if((current_srv_ptr->list_node.prev == NULL) && (current_srv_ptr->list_node.next == NULL))
 145                 {
 146                     break;  /* Abort scheduler service */
 147                 }
 148             }
 149         }
 150         current_srv_ptr = (CService *)(void*)current_srv_ptr->list_node.next;
 151     }
 152     /* Scheduler services finished */
 153     self->scd_srv_is_running = false;
 154 }
 155
 156 /*! \brief  Searches for pending events.
 157  *  \param  self   Instance pointer
 158  *  \return true: At least one event is active
 159  *  \return false: No event is pending
 160  */
 161 bool Scd_AreEventsPending(CScheduler *self)
 162 {
 163     bool ret_val = false;
 164     CService *current_srv_ptr = (CService *)(void*)self->srv_list.head;
 165
 166     while(current_srv_ptr != NULL)
 167     {
 168         if(current_srv_ptr->event_mask != SRV_EMPTY_EVENT_MASK)
 169         {
 170             ret_val = true;
 171             break;
 172         }
 173         current_srv_ptr = (CService *)(void*)current_srv_ptr->list_node.next;
 174     }
 175
 176     return ret_val;
 177 }
 178
 179 /*! \brief  Searches the slot where the new service has to be inserted. The position depends on
 180  *          the given priority. If a the priority of the new service is higher than the priority
 181  *          of the current service \c true is returned which stops the search.
 182  *  \param  current_prio_ptr   Current service which is analyzed
 183  *  \param  new_prio_ptr       Priority of the new service
 184  *  \return false: The priority of the current service is greater than the new priority
 185  *  \return true: The priority of the current service is less than or equal to the new priority
 186  */
 187 static bool Scd_SearchSlot(void *current_prio_ptr, void *new_prio_ptr)
 188 {
 189     uint8_t current_prio_ptr_ = *((uint8_t *)current_prio_ptr);
 190     uint8_t new_prio_ = *((uint8_t*)new_prio_ptr);
 191     bool ret_val = false;
 192
 193     if(current_prio_ptr_ <= new_prio_)
 194     {
 195         ret_val = true;
 196     }
 197
 198     return ret_val;
 199 }
 200
 201 /*------------------------------------------------------------------------------------------------*/
 202 /* Implementation of class CService                                                               */
 203 /*------------------------------------------------------------------------------------------------*/
 204 /*! \brief Parameter constructor of the service class.
 205  *  \param self            Instance pointer
 206  *  \param instance_ptr    Reference to object which contains the corresponding service
 207  *  \param priority        Priority of the service
 208  *  \param service_fptr    Service callback
 209  */
 210 void Srv_Ctor(CService *self, uint8_t priority, void *instance_ptr, Srv_Cb_t service_fptr)
 211 {
 212     MISC_MEM_SET(self, 0, sizeof(*self));
 213     Dln_Ctor(&self->list_node, NULL);
 214     self->priority = priority;
 215     self->instance_ptr = instance_ptr;
 216     self->service_fptr = service_fptr;
 217 }
 218
 219 /*! \brief Sets events for the given service according to the given event mask.
 220  *  \param self        Instance pointer
 221  *  \param event_mask  Mask of the events to be set
 222  */
 223 void Srv_SetEvent(CService *self, Srv_Event_t event_mask)
 224 {
 225     self->event_mask |= event_mask;
 226     if(self->scd_ptr->scd_srv_is_running == false)
 227     {
 228         Ssub_Notify(&self->scd_ptr->service_request_subject, NULL, false);
 229     }
 230 }
 231
 232 /*! \brief The function returns the current state of all event bits of the service.
 233  *  \param self            Instance pointer
 234  *  \param event_mask_ptr  Reference to the memory of the returned event mask
 235  */
 236 void Srv_GetEvent(CService *self, Srv_Event_t *event_mask_ptr)
 237 {
 238     *event_mask_ptr = self->event_mask;
 239 }
 240
 241 /*! \brief Clears events for the given service according to the given event mask.
 242  *  \param self       Instance pointer
 243  *  \param event_mask Mask of the events to be clear
 244  */
 245 void Srv_ClearEvent(CService *self, Srv_Event_t event_mask)
 246 {
 247     self->event_mask &= ~event_mask;
 248 }
 249
 250 /*!
 251  * @}
 252  * \endcond
 253  */
 254
 255 /*------------------------------------------------------------------------------------------------*/
 256 /* End of file                                                                                    */
 257 /*------------------------------------------------------------------------------------------------*/
 258