os_mem.lst

在51上运行的小的OS系统

              *********************************************************************************************************
              */
              
              void DT_XDATA *OSMemGet (OS_MEM DT_XDATA *pmem, INT8U DT_XDATA *err) REENTRANT
              {
                  void DT_XDATA *pblk;
              
              
                  OS_ENTER_CRITICAL();
                  if (pmem->OSMemNFree > 0) {                       /* See if there are any free memory blocks       */
                      pblk                = pmem->OSMemFreeList;    /* Yes, point to next free memory block          */
                      pmem->OSMemFreeList = *(void DT_XDATA * DT_XDATA *)pblk;         /*      Adjust pointer to new fre
             -e list          */
                      pmem->OSMemNFree--;                           /*      One less memory block in this partition  */
                      OS_EXIT_CRITICAL();
                      *err = OS_NO_ERR;                             /*      No error                                 */
                      return (pblk);                                /*      Return memory block to caller            */
                  } else {
                      OS_EXIT_CRITICAL();
                      *err = OS_MEM_NO_FREE_BLKS;                   /* No,  Notify caller of empty memory partition  */
                      return ((void DT_XDATA *)0);                           /*      Return NULL pointer to caller      
             -      */
                  }
              }
              /*$PAGE*/
              /*
              *********************************************************************************************************
              *                                    INITIALIZE MEMORY PARTITION MANAGER
              *
              * Description : This function is called by uC/OS-II to initialize the memory partition manager.  Your
              *               application MUST NOT call this function.
              *
              * Arguments   : none
              *
              * Returns     : none
              *********************************************************************************************************
              */
              
              void OSMemInit (void) REENTRANT
              {
                  OS_MEM DT_XDATA *pmem;
                  INT16U   i;
              
              
                  pmem = (OS_MEM DT_XDATA *)&OSMemTbl[0];                    /* Point to memory control block (MCB)     
             -      */
                  for (i = 0; i < (OS_MAX_MEM_PART - 1); i++) {     /* Init. list of free memory partitions          */
                      pmem->OSMemFreeList = (void DT_XDATA *)&OSMemTbl[i+1]; /* Chain list of free partitions           
             -      */
                      pmem->OSMemAddr     = (void DT_XDATA *)0;              /* Store start address of memory partition 
             -      */
                      pmem->OSMemNFree    = 0;                      /* No free blocks                                */
                      pmem->OSMemNBlks    = 0;                      /* No blocks                                     */
C51 COMPILER V8.08   OS_MEM                                                                11/08/2008 14:01:50 PAGE 4   

                      pmem->OSMemBlkSize  = 0;                      /* Zero size                                     */
                      pmem++;
                  }
                  OSMemTbl[OS_MAX_MEM_PART - 1].OSMemFreeList = (void DT_XDATA *)0;
                  OSMemFreeList                               = (OS_MEM DT_XDATA *)&OSMemTbl[0];
              }
              /*$PAGE*/
              /*
              *********************************************************************************************************
              *                                         RELEASE A MEMORY BLOCK
              *
              * Description : Returns a memory block to a partition
              *
              * Arguments   : pmem    is a pointer to the memory partition control block
              *
              *               pblk    is a pointer to the memory block being released.
              *
              * Returns     : OS_NO_ERR         if the memory block was inserted into the partition
              *               OS_MEM_FULL       if you are returning a memory block to an already FULL memory partition
              *                                 (You freed more blocks than you allocated!)
              *********************************************************************************************************
              */
              
              INT8U OSMemPut (OS_MEM DT_XDATA *pmem, void DT_XDATA *pblk) REENTRANT
              {
                  OS_ENTER_CRITICAL();
                  if (pmem->OSMemNFree >= pmem->OSMemNBlks) {  /* Make sure all blocks not already returned          */
                      OS_EXIT_CRITICAL();
                      return (OS_MEM_FULL);       
                  }
                  *(void DT_XDATA * DT_XDATA *)pblk      = pmem->OSMemFreeList;   /* Insert released block into free blo
             -ck list         */
                  pmem->OSMemFreeList = pblk;
                  pmem->OSMemNFree++;                          /* One more memory block in this partition            */
                  OS_EXIT_CRITICAL();
                  return (OS_NO_ERR);                          /* Notify caller that memory block was released       */
              }
              /*$PAGE*/
              /*
              *********************************************************************************************************
              *                                          QUERY MEMORY PARTITION
              *
              * Description : This function is used to determine the number of free memory blocks and the number of 
              *               used memory blocks from a memory partition.
              *
              * Arguments   : pmem    is a pointer to the memory partition control block
              *
              *               ppdata   is a pointer to a structure that will contain information about the memory
              *                       partition.
              *
              * Returns     : OS_NO_ERR         Always returns no error.
              *********************************************************************************************************
              */
              
              INT8U OSMemQuery (OS_MEM DT_XDATA *pmem, OS_MEM_DATA DT_XDATA *ppdata) REENTRANT
              {
                  OS_ENTER_CRITICAL();
                  ppdata->OSAddr     = pmem->OSMemAddr;
                  ppdata->OSFreeList = pmem->OSMemFreeList;
                  ppdata->OSBlkSize  = pmem->OSMemBlkSize;
                  ppdata->OSNBlks    = pmem->OSMemNBlks;
                  ppdata->OSNFree    = pmem->OSMemNFree;
C51 COMPILER V8.08   OS_MEM                                                                11/08/2008 14:01:50 PAGE 5   

                  OS_EXIT_CRITICAL();
                  ppdata->OSNUsed    = ppdata->OSNBlks - ppdata->OSNFree;
                  return (OS_NO_ERR);                         
              }
              #endif


MODULE INFORMATION:   STATIC OVERLAYABLE
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   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
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   IDATA SIZE       =   ----    ----
   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  0 WARNING(S),  0 ERROR(S)