1 /*
2 * FreeRTOS Kernel V11.1.0
3 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4 *
5 * SPDX-License-Identifier: MIT
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy of
8 * this software and associated documentation files (the "Software"), to deal in
9 * the Software without restriction, including without limitation the rights to
10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11 * the Software, and to permit persons to whom the Software is furnished to do so,
12 * subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in all
15 * copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
19 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
20 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
21 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * https://www.FreeRTOS.org
25 * https://github.com/FreeRTOS
26 *
27 */
28
29 /*
30 * A sample implementation of pvPortMalloc() and vPortFree() that combines
31 * (coalescences) adjacent memory blocks as they are freed, and in so doing
32 * limits memory fragmentation.
33 *
34 * See heap_1.c, heap_2.c and heap_3.c for alternative implementations, and the
35 * memory management pages of https://www.FreeRTOS.org for more information.
36 */
37 #include <stdlib.h>
38 #include <string.h>
39
40 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
41 * all the API functions to use the MPU wrappers. That should only be done when
42 * task.h is included from an application file. */
43 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
44
45 #include "FreeRTOS.h"
46 #include "task.h"
47
48 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE
49
50 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 0 )
51 #error This file must not be used if configSUPPORT_DYNAMIC_ALLOCATION is 0
52 #endif
53
54 #ifndef configHEAP_CLEAR_MEMORY_ON_FREE
55 #define configHEAP_CLEAR_MEMORY_ON_FREE 0
56 #endif
57
58 /* Block sizes must not get too small. */
59 #define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( xHeapStructSize << 1 ) )
60
61 /* Assumes 8bit bytes! */
62 #define heapBITS_PER_BYTE ( ( size_t ) 8 )
63
64 /* Max value that fits in a size_t type. */
65 #define heapSIZE_MAX ( ~( ( size_t ) 0 ) )
66
67 /* Check if multiplying a and b will result in overflow. */
68 #define heapMULTIPLY_WILL_OVERFLOW( a, b ) ( ( ( a ) > 0 ) && ( ( b ) > ( heapSIZE_MAX / ( a ) ) ) )
69
70 /* Check if adding a and b will result in overflow. */
71 #define heapADD_WILL_OVERFLOW( a, b ) ( ( a ) > ( heapSIZE_MAX - ( b ) ) )
72
73 /* Check if the subtraction operation ( a - b ) will result in underflow. */
74 #define heapSUBTRACT_WILL_UNDERFLOW( a, b ) ( ( a ) < ( b ) )
75
76 /* MSB of the xBlockSize member of an BlockLink_t structure is used to track
77 * the allocation status of a block. When MSB of the xBlockSize member of
78 * an BlockLink_t structure is set then the block belongs to the application.
79 * When the bit is free the block is still part of the free heap space. */
80 #define heapBLOCK_ALLOCATED_BITMASK ( ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 ) )
81 #define heapBLOCK_SIZE_IS_VALID( xBlockSize ) ( ( ( xBlockSize ) & heapBLOCK_ALLOCATED_BITMASK ) == 0 )
82 #define heapBLOCK_IS_ALLOCATED( pxBlock ) ( ( ( pxBlock->xBlockSize ) & heapBLOCK_ALLOCATED_BITMASK ) != 0 )
83 #define heapALLOCATE_BLOCK( pxBlock ) ( ( pxBlock->xBlockSize ) |= heapBLOCK_ALLOCATED_BITMASK )
84 #define heapFREE_BLOCK( pxBlock ) ( ( pxBlock->xBlockSize ) &= ~heapBLOCK_ALLOCATED_BITMASK )
85
86 /*-----------------------------------------------------------*/
87
88 /* Allocate the memory for the heap. */
89 #if ( configAPPLICATION_ALLOCATED_HEAP == 1 )
90
91 /* The application writer has already defined the array used for the RTOS
92 * heap - probably so it can be placed in a special segment or address. */
93 extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
94 #else
95 PRIVILEGED_DATA static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
96 #endif /* configAPPLICATION_ALLOCATED_HEAP */
97
98 /* Define the linked list structure. This is used to link free blocks in order
99 * of their memory address. */
100 typedef struct A_BLOCK_LINK
101 {
102 struct A_BLOCK_LINK * pxNextFreeBlock; /**< The next free block in the list. */
103 size_t xBlockSize; /**< The size of the free block. */
104 } BlockLink_t;
105
106 /* Setting configENABLE_HEAP_PROTECTOR to 1 enables heap block pointers
107 * protection using an application supplied canary value to catch heap
108 * corruption should a heap buffer overflow occur.
109 */
110 #if ( configENABLE_HEAP_PROTECTOR == 1 )
111
112 /**
113 * @brief Application provided function to get a random value to be used as canary.
114 *
115 * @param pxHeapCanary [out] Output parameter to return the canary value.
116 */
117 extern void vApplicationGetRandomHeapCanary( portPOINTER_SIZE_TYPE * pxHeapCanary );
118
119 /* Canary value for protecting internal heap pointers. */
120 PRIVILEGED_DATA static portPOINTER_SIZE_TYPE xHeapCanary;
121
122 /* Macro to load/store BlockLink_t pointers to memory. By XORing the
123 * pointers with a random canary value, heap overflows will result
124 * in randomly unpredictable pointer values which will be caught by
125 * heapVALIDATE_BLOCK_POINTER assert. */
126 #define heapPROTECT_BLOCK_POINTER( pxBlock ) ( ( BlockLink_t * ) ( ( ( portPOINTER_SIZE_TYPE ) ( pxBlock ) ) ^ xHeapCanary ) )
127 #else
128
129 #define heapPROTECT_BLOCK_POINTER( pxBlock ) ( pxBlock )
130
131 #endif /* configENABLE_HEAP_PROTECTOR */
132
133 /* Assert that a heap block pointer is within the heap bounds. */
134 #define heapVALIDATE_BLOCK_POINTER( pxBlock ) \
135 configASSERT( ( ( uint8_t * ) ( pxBlock ) >= &( ucHeap[ 0 ] ) ) && \
136 ( ( uint8_t * ) ( pxBlock ) <= &( ucHeap[ configTOTAL_HEAP_SIZE - 1 ] ) ) )
137
138 /*-----------------------------------------------------------*/
139
140 /*
141 * Inserts a block of memory that is being freed into the correct position in
142 * the list of free memory blocks. The block being freed will be merged with
143 * the block in front it and/or the block behind it if the memory blocks are
144 * adjacent to each other.
145 */
146 static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert ) PRIVILEGED_FUNCTION;
147
148 /*
149 * Called automatically to setup the required heap structures the first time
150 * pvPortMalloc() is called.
151 */
152 static void prvHeapInit( void ) PRIVILEGED_FUNCTION;
153
154 /*-----------------------------------------------------------*/
155
156 /* The size of the structure placed at the beginning of each allocated memory
157 * block must by correctly byte aligned. */
158 static const size_t xHeapStructSize = ( sizeof( BlockLink_t ) + ( ( size_t ) ( portBYTE_ALIGNMENT - 1 ) ) ) & ~( ( size_t ) portBYTE_ALIGNMENT_MASK );
159
160 /* Create a couple of list links to mark the start and end of the list. */
161 PRIVILEGED_DATA static BlockLink_t xStart;
162 PRIVILEGED_DATA static BlockLink_t * pxEnd = NULL;
163
164 /* Keeps track of the number of calls to allocate and free memory as well as the
165 * number of free bytes remaining, but says nothing about fragmentation. */
166 PRIVILEGED_DATA static size_t xFreeBytesRemaining = ( size_t ) 0U;
167 PRIVILEGED_DATA static size_t xMinimumEverFreeBytesRemaining = ( size_t ) 0U;
168 PRIVILEGED_DATA static size_t xNumberOfSuccessfulAllocations = ( size_t ) 0U;
169 PRIVILEGED_DATA static size_t xNumberOfSuccessfulFrees = ( size_t ) 0U;
170
171 /*-----------------------------------------------------------*/
172
pvPortMalloc(size_t xWantedSize)173 void * pvPortMalloc( size_t xWantedSize )
174 {
175 BlockLink_t * pxBlock;
176 BlockLink_t * pxPreviousBlock;
177 BlockLink_t * pxNewBlockLink;
178 void * pvReturn = NULL;
179 size_t xAdditionalRequiredSize;
180
181 if( xWantedSize > 0 )
182 {
183 /* The wanted size must be increased so it can contain a BlockLink_t
184 * structure in addition to the requested amount of bytes. */
185 if( heapADD_WILL_OVERFLOW( xWantedSize, xHeapStructSize ) == 0 )
186 {
187 xWantedSize += xHeapStructSize;
188
189 /* Ensure that blocks are always aligned to the required number
190 * of bytes. */
191 if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )
192 {
193 /* Byte alignment required. */
194 xAdditionalRequiredSize = portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK );
195
196 if( heapADD_WILL_OVERFLOW( xWantedSize, xAdditionalRequiredSize ) == 0 )
197 {
198 xWantedSize += xAdditionalRequiredSize;
199 }
200 else
201 {
202 xWantedSize = 0;
203 }
204 }
205 else
206 {
207 mtCOVERAGE_TEST_MARKER();
208 }
209 }
210 else
211 {
212 xWantedSize = 0;
213 }
214 }
215 else
216 {
217 mtCOVERAGE_TEST_MARKER();
218 }
219
220 vTaskSuspendAll();
221 {
222 /* If this is the first call to malloc then the heap will require
223 * initialisation to setup the list of free blocks. */
224 if( pxEnd == NULL )
225 {
226 prvHeapInit();
227 }
228 else
229 {
230 mtCOVERAGE_TEST_MARKER();
231 }
232
233 /* Check the block size we are trying to allocate is not so large that the
234 * top bit is set. The top bit of the block size member of the BlockLink_t
235 * structure is used to determine who owns the block - the application or
236 * the kernel, so it must be free. */
237 if( heapBLOCK_SIZE_IS_VALID( xWantedSize ) != 0 )
238 {
239 if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) )
240 {
241 /* Traverse the list from the start (lowest address) block until
242 * one of adequate size is found. */
243 pxPreviousBlock = &xStart;
244 pxBlock = heapPROTECT_BLOCK_POINTER( xStart.pxNextFreeBlock );
245 heapVALIDATE_BLOCK_POINTER( pxBlock );
246
247 while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != heapPROTECT_BLOCK_POINTER( NULL ) ) )
248 {
249 pxPreviousBlock = pxBlock;
250 pxBlock = heapPROTECT_BLOCK_POINTER( pxBlock->pxNextFreeBlock );
251 heapVALIDATE_BLOCK_POINTER( pxBlock );
252 }
253
254 /* If the end marker was reached then a block of adequate size
255 * was not found. */
256 if( pxBlock != pxEnd )
257 {
258 /* Return the memory space pointed to - jumping over the
259 * BlockLink_t structure at its start. */
260 pvReturn = ( void * ) ( ( ( uint8_t * ) heapPROTECT_BLOCK_POINTER( pxPreviousBlock->pxNextFreeBlock ) ) + xHeapStructSize );
261 heapVALIDATE_BLOCK_POINTER( pvReturn );
262
263 /* This block is being returned for use so must be taken out
264 * of the list of free blocks. */
265 pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock;
266
267 /* If the block is larger than required it can be split into
268 * two. */
269 configASSERT( heapSUBTRACT_WILL_UNDERFLOW( pxBlock->xBlockSize, xWantedSize ) == 0 );
270
271 if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE )
272 {
273 /* This block is to be split into two. Create a new
274 * block following the number of bytes requested. The void
275 * cast is used to prevent byte alignment warnings from the
276 * compiler. */
277 pxNewBlockLink = ( void * ) ( ( ( uint8_t * ) pxBlock ) + xWantedSize );
278 configASSERT( ( ( ( size_t ) pxNewBlockLink ) & portBYTE_ALIGNMENT_MASK ) == 0 );
279
280 /* Calculate the sizes of two blocks split from the
281 * single block. */
282 pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize;
283 pxBlock->xBlockSize = xWantedSize;
284
285 /* Insert the new block into the list of free blocks. */
286 pxNewBlockLink->pxNextFreeBlock = pxPreviousBlock->pxNextFreeBlock;
287 pxPreviousBlock->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxNewBlockLink );
288 }
289 else
290 {
291 mtCOVERAGE_TEST_MARKER();
292 }
293
294 xFreeBytesRemaining -= pxBlock->xBlockSize;
295
296 if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining )
297 {
298 xMinimumEverFreeBytesRemaining = xFreeBytesRemaining;
299 }
300 else
301 {
302 mtCOVERAGE_TEST_MARKER();
303 }
304
305 /* The block is being returned - it is allocated and owned
306 * by the application and has no "next" block. */
307 heapALLOCATE_BLOCK( pxBlock );
308 pxBlock->pxNextFreeBlock = NULL;
309 xNumberOfSuccessfulAllocations++;
310 }
311 else
312 {
313 mtCOVERAGE_TEST_MARKER();
314 }
315 }
316 else
317 {
318 mtCOVERAGE_TEST_MARKER();
319 }
320 }
321 else
322 {
323 mtCOVERAGE_TEST_MARKER();
324 }
325
326 traceMALLOC( pvReturn, xWantedSize );
327 }
328 ( void ) xTaskResumeAll();
329
330 #if ( configUSE_MALLOC_FAILED_HOOK == 1 )
331 {
332 if( pvReturn == NULL )
333 {
334 vApplicationMallocFailedHook();
335 }
336 else
337 {
338 mtCOVERAGE_TEST_MARKER();
339 }
340 }
341 #endif /* if ( configUSE_MALLOC_FAILED_HOOK == 1 ) */
342
343 configASSERT( ( ( ( size_t ) pvReturn ) & ( size_t ) portBYTE_ALIGNMENT_MASK ) == 0 );
344 return pvReturn;
345 }
346 /*-----------------------------------------------------------*/
347
vPortFree(void * pv)348 void vPortFree( void * pv )
349 {
350 uint8_t * puc = ( uint8_t * ) pv;
351 BlockLink_t * pxLink;
352
353 if( pv != NULL )
354 {
355 /* The memory being freed will have an BlockLink_t structure immediately
356 * before it. */
357 puc -= xHeapStructSize;
358
359 /* This casting is to keep the compiler from issuing warnings. */
360 pxLink = ( void * ) puc;
361
362 heapVALIDATE_BLOCK_POINTER( pxLink );
363 configASSERT( heapBLOCK_IS_ALLOCATED( pxLink ) != 0 );
364 configASSERT( pxLink->pxNextFreeBlock == NULL );
365
366 if( heapBLOCK_IS_ALLOCATED( pxLink ) != 0 )
367 {
368 if( pxLink->pxNextFreeBlock == NULL )
369 {
370 /* The block is being returned to the heap - it is no longer
371 * allocated. */
372 heapFREE_BLOCK( pxLink );
373 #if ( configHEAP_CLEAR_MEMORY_ON_FREE == 1 )
374 {
375 /* Check for underflow as this can occur if xBlockSize is
376 * overwritten in a heap block. */
377 if( heapSUBTRACT_WILL_UNDERFLOW( pxLink->xBlockSize, xHeapStructSize ) == 0 )
378 {
379 ( void ) memset( puc + xHeapStructSize, 0, pxLink->xBlockSize - xHeapStructSize );
380 }
381 }
382 #endif
383
384 vTaskSuspendAll();
385 {
386 /* Add this block to the list of free blocks. */
387 xFreeBytesRemaining += pxLink->xBlockSize;
388 traceFREE( pv, pxLink->xBlockSize );
389 prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) );
390 xNumberOfSuccessfulFrees++;
391 }
392 ( void ) xTaskResumeAll();
393 }
394 else
395 {
396 mtCOVERAGE_TEST_MARKER();
397 }
398 }
399 else
400 {
401 mtCOVERAGE_TEST_MARKER();
402 }
403 }
404 }
405 /*-----------------------------------------------------------*/
406
xPortGetFreeHeapSize(void)407 size_t xPortGetFreeHeapSize( void )
408 {
409 return xFreeBytesRemaining;
410 }
411 /*-----------------------------------------------------------*/
412
xPortGetMinimumEverFreeHeapSize(void)413 size_t xPortGetMinimumEverFreeHeapSize( void )
414 {
415 return xMinimumEverFreeBytesRemaining;
416 }
417 /*-----------------------------------------------------------*/
418
vPortInitialiseBlocks(void)419 void vPortInitialiseBlocks( void )
420 {
421 /* This just exists to keep the linker quiet. */
422 }
423 /*-----------------------------------------------------------*/
424
pvPortCalloc(size_t xNum,size_t xSize)425 void * pvPortCalloc( size_t xNum,
426 size_t xSize )
427 {
428 void * pv = NULL;
429
430 if( heapMULTIPLY_WILL_OVERFLOW( xNum, xSize ) == 0 )
431 {
432 pv = pvPortMalloc( xNum * xSize );
433
434 if( pv != NULL )
435 {
436 ( void ) memset( pv, 0, xNum * xSize );
437 }
438 }
439
440 return pv;
441 }
442 /*-----------------------------------------------------------*/
443
prvHeapInit(void)444 static void prvHeapInit( void ) /* PRIVILEGED_FUNCTION */
445 {
446 BlockLink_t * pxFirstFreeBlock;
447 portPOINTER_SIZE_TYPE uxStartAddress, uxEndAddress;
448 size_t xTotalHeapSize = configTOTAL_HEAP_SIZE;
449
450 /* Ensure the heap starts on a correctly aligned boundary. */
451 uxStartAddress = ( portPOINTER_SIZE_TYPE ) ucHeap;
452
453 if( ( uxStartAddress & portBYTE_ALIGNMENT_MASK ) != 0 )
454 {
455 uxStartAddress += ( portBYTE_ALIGNMENT - 1 );
456 uxStartAddress &= ~( ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK );
457 xTotalHeapSize -= ( size_t ) ( uxStartAddress - ( portPOINTER_SIZE_TYPE ) ucHeap );
458 }
459
460 #if ( configENABLE_HEAP_PROTECTOR == 1 )
461 {
462 vApplicationGetRandomHeapCanary( &( xHeapCanary ) );
463 }
464 #endif
465
466 /* xStart is used to hold a pointer to the first item in the list of free
467 * blocks. The void cast is used to prevent compiler warnings. */
468 xStart.pxNextFreeBlock = ( void * ) heapPROTECT_BLOCK_POINTER( uxStartAddress );
469 xStart.xBlockSize = ( size_t ) 0;
470
471 /* pxEnd is used to mark the end of the list of free blocks and is inserted
472 * at the end of the heap space. */
473 uxEndAddress = uxStartAddress + ( portPOINTER_SIZE_TYPE ) xTotalHeapSize;
474 uxEndAddress -= ( portPOINTER_SIZE_TYPE ) xHeapStructSize;
475 uxEndAddress &= ~( ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK );
476 pxEnd = ( BlockLink_t * ) uxEndAddress;
477 pxEnd->xBlockSize = 0;
478 pxEnd->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( NULL );
479
480 /* To start with there is a single free block that is sized to take up the
481 * entire heap space, minus the space taken by pxEnd. */
482 pxFirstFreeBlock = ( BlockLink_t * ) uxStartAddress;
483 pxFirstFreeBlock->xBlockSize = ( size_t ) ( uxEndAddress - ( portPOINTER_SIZE_TYPE ) pxFirstFreeBlock );
484 pxFirstFreeBlock->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxEnd );
485
486 /* Only one block exists - and it covers the entire usable heap space. */
487 xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;
488 xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;
489 }
490 /*-----------------------------------------------------------*/
491
prvInsertBlockIntoFreeList(BlockLink_t * pxBlockToInsert)492 static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert ) /* PRIVILEGED_FUNCTION */
493 {
494 BlockLink_t * pxIterator;
495 uint8_t * puc;
496
497 /* Iterate through the list until a block is found that has a higher address
498 * than the block being inserted. */
499 for( pxIterator = &xStart; heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) < pxBlockToInsert; pxIterator = heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) )
500 {
501 /* Nothing to do here, just iterate to the right position. */
502 }
503
504 if( pxIterator != &xStart )
505 {
506 heapVALIDATE_BLOCK_POINTER( pxIterator );
507 }
508
509 /* Do the block being inserted, and the block it is being inserted after
510 * make a contiguous block of memory? */
511 puc = ( uint8_t * ) pxIterator;
512
513 if( ( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert )
514 {
515 pxIterator->xBlockSize += pxBlockToInsert->xBlockSize;
516 pxBlockToInsert = pxIterator;
517 }
518 else
519 {
520 mtCOVERAGE_TEST_MARKER();
521 }
522
523 /* Do the block being inserted, and the block it is being inserted before
524 * make a contiguous block of memory? */
525 puc = ( uint8_t * ) pxBlockToInsert;
526
527 if( ( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) )
528 {
529 if( heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) != pxEnd )
530 {
531 /* Form one big block from the two blocks. */
532 pxBlockToInsert->xBlockSize += heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )->xBlockSize;
533 pxBlockToInsert->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )->pxNextFreeBlock;
534 }
535 else
536 {
537 pxBlockToInsert->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxEnd );
538 }
539 }
540 else
541 {
542 pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock;
543 }
544
545 /* If the block being inserted plugged a gab, so was merged with the block
546 * before and the block after, then it's pxNextFreeBlock pointer will have
547 * already been set, and should not be set here as that would make it point
548 * to itself. */
549 if( pxIterator != pxBlockToInsert )
550 {
551 pxIterator->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxBlockToInsert );
552 }
553 else
554 {
555 mtCOVERAGE_TEST_MARKER();
556 }
557 }
558 /*-----------------------------------------------------------*/
559
vPortGetHeapStats(HeapStats_t * pxHeapStats)560 void vPortGetHeapStats( HeapStats_t * pxHeapStats )
561 {
562 BlockLink_t * pxBlock;
563 size_t xBlocks = 0, xMaxSize = 0, xMinSize = portMAX_DELAY; /* portMAX_DELAY used as a portable way of getting the maximum value. */
564
565 vTaskSuspendAll();
566 {
567 pxBlock = heapPROTECT_BLOCK_POINTER( xStart.pxNextFreeBlock );
568
569 /* pxBlock will be NULL if the heap has not been initialised. The heap
570 * is initialised automatically when the first allocation is made. */
571 if( pxBlock != NULL )
572 {
573 while( pxBlock != pxEnd )
574 {
575 /* Increment the number of blocks and record the largest block seen
576 * so far. */
577 xBlocks++;
578
579 if( pxBlock->xBlockSize > xMaxSize )
580 {
581 xMaxSize = pxBlock->xBlockSize;
582 }
583
584 if( pxBlock->xBlockSize < xMinSize )
585 {
586 xMinSize = pxBlock->xBlockSize;
587 }
588
589 /* Move to the next block in the chain until the last block is
590 * reached. */
591 pxBlock = heapPROTECT_BLOCK_POINTER( pxBlock->pxNextFreeBlock );
592 }
593 }
594 }
595 ( void ) xTaskResumeAll();
596
597 pxHeapStats->xSizeOfLargestFreeBlockInBytes = xMaxSize;
598 pxHeapStats->xSizeOfSmallestFreeBlockInBytes = xMinSize;
599 pxHeapStats->xNumberOfFreeBlocks = xBlocks;
600
601 taskENTER_CRITICAL();
602 {
603 pxHeapStats->xAvailableHeapSpaceInBytes = xFreeBytesRemaining;
604 pxHeapStats->xNumberOfSuccessfulAllocations = xNumberOfSuccessfulAllocations;
605 pxHeapStats->xNumberOfSuccessfulFrees = xNumberOfSuccessfulFrees;
606 pxHeapStats->xMinimumEverFreeBytesRemaining = xMinimumEverFreeBytesRemaining;
607 }
608 taskEXIT_CRITICAL();
609 }
610 /*-----------------------------------------------------------*/
611
612 /*
613 * Reset the state in this file. This state is normally initialized at start up.
614 * This function must be called by the application before restarting the
615 * scheduler.
616 */
vPortHeapResetState(void)617 void vPortHeapResetState( void )
618 {
619 pxEnd = NULL;
620
621 xFreeBytesRemaining = ( size_t ) 0U;
622 xMinimumEverFreeBytesRemaining = ( size_t ) 0U;
623 xNumberOfSuccessfulAllocations = ( size_t ) 0U;
624 xNumberOfSuccessfulFrees = ( size_t ) 0U;
625 }
626 /*-----------------------------------------------------------*/
627
