1 /*
2  * FreeRTOS Kernel V10.4.3
3  * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
6  * this software and associated documentation files (the "Software"), to deal in
7  * the Software without restriction, including without limitation the rights to
8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
9  * the Software, and to permit persons to whom the Software is furnished to do so,
10  * subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in all
13  * copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
17  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
18  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
19  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * https://www.FreeRTOS.org
23  * https://github.com/FreeRTOS
24  *
25  */
26 
27 /* Standard includes. */
28 #include <stdint.h>
29 #include <string.h>
30 
31 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
32  * all the API functions to use the MPU wrappers.  That should only be done when
33  * task.h is included from an application file. */
34 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
35 
36 /* FreeRTOS includes. */
37 #include "FreeRTOS.h"
38 #include "task.h"
39 #include "stream_buffer.h"
40 
41 #ifdef ESP_PLATFORM
42 #define taskCRITICAL_MUX &pxStreamBuffer->xStreamBufferMux
43 #undef taskENTER_CRITICAL
44 #undef taskEXIT_CRITICAL
45 #undef taskENTER_CRITICAL_ISR
46 #undef taskEXIT_CRITICAL_ISR
47 #define taskENTER_CRITICAL( )     portENTER_CRITICAL( taskCRITICAL_MUX )
48 #define taskEXIT_CRITICAL( )            portEXIT_CRITICAL( taskCRITICAL_MUX )
49 #define taskENTER_CRITICAL_ISR( )     portENTER_CRITICAL_ISR( taskCRITICAL_MUX )
50 #define taskEXIT_CRITICAL_ISR( )        portEXIT_CRITICAL_ISR( taskCRITICAL_MUX )
51 #endif
52 
53 #if ( configUSE_TASK_NOTIFICATIONS != 1 )
54     #error configUSE_TASK_NOTIFICATIONS must be set to 1 to build stream_buffer.c
55 #endif
56 
57 /* Lint e961, e9021 and e750 are suppressed as a MISRA exception justified
58  * because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
59  * for the header files above, but not in this file, in order to generate the
60  * correct privileged Vs unprivileged linkage and placement. */
61 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750 !e9021. */
62 
63 /* If the user has not provided application specific Rx notification macros,
64  * or #defined the notification macros away, then provide default implementations
65  * that uses task notifications. */
66 /*lint -save -e9026 Function like macros allowed and needed here so they can be overridden. */
67 
68 #ifndef sbRECEIVE_COMPLETED
69 #ifdef ESP_PLATFORM // IDF-3775
70     #define sbRECEIVE_COMPLETED( pxStreamBuffer )                         \
71     taskENTER_CRITICAL();                                                 \
72     {                                                                     \
73         if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )              \
74         {                                                                 \
75             ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToSend, \
76                                   ( uint32_t ) 0,                         \
77                                   eNoAction );                            \
78             ( pxStreamBuffer )->xTaskWaitingToSend = NULL;                \
79         }                                                                 \
80     }                                                                     \
81     taskEXIT_CRITICAL();
82 #else
83     #define sbRECEIVE_COMPLETED( pxStreamBuffer )                         \
84     vTaskSuspendAll();                                                    \
85     {                                                                     \
86         if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )              \
87         {                                                                 \
88             ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToSend, \
89                                   ( uint32_t ) 0,                         \
90                                   eNoAction );                            \
91             ( pxStreamBuffer )->xTaskWaitingToSend = NULL;                \
92         }                                                                 \
93     }                                                                     \
94     ( void ) xTaskResumeAll();
95 #endif // ESP_PLATFORM
96 #endif /* sbRECEIVE_COMPLETED */
97 
98 #ifndef sbRECEIVE_COMPLETED_FROM_ISR
99     #define sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer,                            \
100                                           pxHigherPriorityTaskWoken )                \
101     {                                                                                \
102         UBaseType_t uxSavedInterruptStatus;                                          \
103                                                                                      \
104         uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();  \
105         {                                                                            \
106             if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )                     \
107             {                                                                        \
108                 ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend, \
109                                              ( uint32_t ) 0,                         \
110                                              eNoAction,                              \
111                                              pxHigherPriorityTaskWoken );            \
112                 ( pxStreamBuffer )->xTaskWaitingToSend = NULL;                       \
113             }                                                                        \
114         }                                                                            \
115         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );                 \
116     }
117 #endif /* sbRECEIVE_COMPLETED_FROM_ISR */
118 
119 /* If the user has not provided an application specific Tx notification macro,
120  * or #defined the notification macro away, them provide a default implementation
121  * that uses task notifications. */
122 #ifndef sbSEND_COMPLETED
123 #ifdef ESP_PLATFORM // IDF-3755
124     #define sbSEND_COMPLETED( pxStreamBuffer )                               \
125     taskENTER_CRITICAL();                                                    \
126     {                                                                        \
127         if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )              \
128         {                                                                    \
129             ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToReceive, \
130                                   ( uint32_t ) 0,                            \
131                                   eNoAction );                               \
132             ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;                \
133         }                                                                    \
134     }                                                                        \
135     taskEXIT_CRITICAL();
136 #else
137     #define sbSEND_COMPLETED( pxStreamBuffer )                               \
138     vTaskSuspendAll();                                                       \
139     {                                                                        \
140         if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )              \
141         {                                                                    \
142             ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToReceive, \
143                                   ( uint32_t ) 0,                            \
144                                   eNoAction );                               \
145             ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;                \
146         }                                                                    \
147     }                                                                        \
148     ( void ) xTaskResumeAll();
149 #endif // ESP_PLATFORM
150 #endif /* sbSEND_COMPLETED */
151 
152 #ifndef sbSEND_COMPLETE_FROM_ISR
153     #define sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken )       \
154     {                                                                                   \
155         UBaseType_t uxSavedInterruptStatus;                                             \
156                                                                                         \
157         uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();     \
158         {                                                                               \
159             if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )                     \
160             {                                                                           \
161                 ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive, \
162                                              ( uint32_t ) 0,                            \
163                                              eNoAction,                                 \
164                                              pxHigherPriorityTaskWoken );               \
165                 ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;                       \
166             }                                                                           \
167         }                                                                               \
168         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );                    \
169     }
170 #endif /* sbSEND_COMPLETE_FROM_ISR */
171 /*lint -restore (9026) */
172 
173 /* The number of bytes used to hold the length of a message in the buffer. */
174 #define sbBYTES_TO_STORE_MESSAGE_LENGTH    ( sizeof( configMESSAGE_BUFFER_LENGTH_TYPE ) )
175 
176 /* Bits stored in the ucFlags field of the stream buffer. */
177 #define sbFLAGS_IS_MESSAGE_BUFFER          ( ( uint8_t ) 1 ) /* Set if the stream buffer was created as a message buffer, in which case it holds discrete messages rather than a stream. */
178 #define sbFLAGS_IS_STATICALLY_ALLOCATED    ( ( uint8_t ) 2 ) /* Set if the stream buffer was created using statically allocated memory. */
179 
180 /*-----------------------------------------------------------*/
181 
182 /* Structure that hold state information on the buffer. */
183 typedef struct StreamBufferDef_t                 /*lint !e9058 Style convention uses tag. */
184 {
185     volatile size_t xTail;                       /* Index to the next item to read within the buffer. */
186     volatile size_t xHead;                       /* Index to the next item to write within the buffer. */
187     size_t xLength;                              /* The length of the buffer pointed to by pucBuffer. */
188     size_t xTriggerLevelBytes;                   /* The number of bytes that must be in the stream buffer before a task that is waiting for data is unblocked. */
189     volatile TaskHandle_t xTaskWaitingToReceive; /* Holds the handle of a task waiting for data, or NULL if no tasks are waiting. */
190     volatile TaskHandle_t xTaskWaitingToSend;    /* Holds the handle of a task waiting to send data to a message buffer that is full. */
191     uint8_t * pucBuffer;                         /* Points to the buffer itself - that is - the RAM that stores the data passed through the buffer. */
192     uint8_t ucFlags;
193 
194     #if ( configUSE_TRACE_FACILITY == 1 )
195         UBaseType_t uxStreamBufferNumber; /* Used for tracing purposes. */
196     #endif
197 #ifdef ESP_PLATFORM
198     /* Mutex required due to SMP. This field shall be the last one of the structure. */
199     portMUX_TYPE xStreamBufferMux;
200 #endif // ESP_PLATFORM
201 } StreamBuffer_t;
202 
203 /*
204  * The number of bytes available to be read from the buffer.
205  */
206 static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer ) PRIVILEGED_FUNCTION;
207 
208 /*
209  * Add xCount bytes from pucData into the pxStreamBuffer message buffer.
210  * Returns the number of bytes written, which will either equal xCount in the
211  * success case, or 0 if there was not enough space in the buffer (in which case
212  * no data is written into the buffer).
213  */
214 static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
215                                      const uint8_t * pucData,
216                                      size_t xCount ) PRIVILEGED_FUNCTION;
217 
218 /*
219  * If the stream buffer is being used as a message buffer, then reads an entire
220  * message out of the buffer.  If the stream buffer is being used as a stream
221  * buffer then read as many bytes as possible from the buffer.
222  * prvReadBytesFromBuffer() is called to actually extract the bytes from the
223  * buffer's data storage area.
224  */
225 static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
226                                         void * pvRxData,
227                                         size_t xBufferLengthBytes,
228                                         size_t xBytesAvailable,
229                                         size_t xBytesToStoreMessageLength ) PRIVILEGED_FUNCTION;
230 
231 /*
232  * If the stream buffer is being used as a message buffer, then writes an entire
233  * message to the buffer.  If the stream buffer is being used as a stream
234  * buffer then write as many bytes as possible to the buffer.
235  * prvWriteBytestoBuffer() is called to actually send the bytes to the buffer's
236  * data storage area.
237  */
238 static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
239                                        const void * pvTxData,
240                                        size_t xDataLengthBytes,
241                                        size_t xSpace,
242                                        size_t xRequiredSpace ) PRIVILEGED_FUNCTION;
243 
244 /*
245  * Read xMaxCount bytes from the pxStreamBuffer message buffer and write them
246  * to pucData.
247  */
248 static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
249                                       uint8_t * pucData,
250                                       size_t xMaxCount,
251                                       size_t xBytesAvailable ) PRIVILEGED_FUNCTION;
252 
253 /*
254  * Called by both pxStreamBufferCreate() and pxStreamBufferCreateStatic() to
255  * initialise the members of the newly created stream buffer structure.
256  */
257 static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
258                                           uint8_t * const pucBuffer,
259                                           size_t xBufferSizeBytes,
260                                           size_t xTriggerLevelBytes,
261                                           uint8_t ucFlags ) PRIVILEGED_FUNCTION;
262 
263 #ifdef ESP_PLATFORM
264 /**
265  * Called by xStreamBufferReset() to reset the members of the StreamBuffer, excluding
266  * its spinlock.
267  */
268 static void prvResetStreamBufferFields( StreamBuffer_t * const pxStreamBuffer,
269                                         uint8_t * const pucBuffer,
270                                         size_t xBufferSizeBytes,
271                                         size_t xTriggerLevelBytes,
272                                         uint8_t ucFlags ) PRIVILEGED_FUNCTION;
273 #endif
274 /*-----------------------------------------------------------*/
275 
276 #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
277 
xStreamBufferGenericCreate(size_t xBufferSizeBytes,size_t xTriggerLevelBytes,BaseType_t xIsMessageBuffer)278     StreamBufferHandle_t xStreamBufferGenericCreate( size_t xBufferSizeBytes,
279                                                      size_t xTriggerLevelBytes,
280                                                      BaseType_t xIsMessageBuffer )
281     {
282         uint8_t * pucAllocatedMemory;
283         uint8_t ucFlags;
284 
285         /* In case the stream buffer is going to be used as a message buffer
286          * (that is, it will hold discrete messages with a little meta data that
287          * says how big the next message is) check the buffer will be large enough
288          * to hold at least one message. */
289         if( xIsMessageBuffer == pdTRUE )
290         {
291             /* Is a message buffer but not statically allocated. */
292             ucFlags = sbFLAGS_IS_MESSAGE_BUFFER;
293             configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
294         }
295         else
296         {
297             /* Not a message buffer and not statically allocated. */
298             ucFlags = 0;
299             configASSERT( xBufferSizeBytes > 0 );
300         }
301 
302         configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
303 
304         /* A trigger level of 0 would cause a waiting task to unblock even when
305          * the buffer was empty. */
306         if( xTriggerLevelBytes == ( size_t ) 0 )
307         {
308             xTriggerLevelBytes = ( size_t ) 1;
309         }
310 
311         /* A stream buffer requires a StreamBuffer_t structure and a buffer.
312          * Both are allocated in a single call to pvPortMalloc().  The
313          * StreamBuffer_t structure is placed at the start of the allocated memory
314          * and the buffer follows immediately after.  The requested size is
315          * incremented so the free space is returned as the user would expect -
316          * this is a quirk of the implementation that means otherwise the free
317          * space would be reported as one byte smaller than would be logically
318          * expected. */
319         if( xBufferSizeBytes < ( xBufferSizeBytes + 1 + sizeof( StreamBuffer_t ) ) )
320         {
321             xBufferSizeBytes++;
322             pucAllocatedMemory = ( uint8_t * ) pvPortMalloc( xBufferSizeBytes + sizeof( StreamBuffer_t ) ); /*lint !e9079 malloc() only returns void*. */
323         }
324         else
325         {
326             pucAllocatedMemory = NULL;
327         }
328 
329         if( pucAllocatedMemory != NULL )
330         {
331             prvInitialiseNewStreamBuffer( ( StreamBuffer_t * ) pucAllocatedMemory,       /* Structure at the start of the allocated memory. */ /*lint !e9087 Safe cast as allocated memory is aligned. */ /*lint !e826 Area is not too small and alignment is guaranteed provided malloc() behaves as expected and returns aligned buffer. */
332                                           pucAllocatedMemory + sizeof( StreamBuffer_t ), /* Storage area follows. */ /*lint !e9016 Indexing past structure valid for uint8_t pointer, also storage area has no alignment requirement. */
333                                           xBufferSizeBytes,
334                                           xTriggerLevelBytes,
335                                           ucFlags );
336 
337             traceSTREAM_BUFFER_CREATE( ( ( StreamBuffer_t * ) pucAllocatedMemory ), xIsMessageBuffer );
338         }
339         else
340         {
341             traceSTREAM_BUFFER_CREATE_FAILED( xIsMessageBuffer );
342         }
343 
344         return ( StreamBufferHandle_t ) pucAllocatedMemory; /*lint !e9087 !e826 Safe cast as allocated memory is aligned. */
345     }
346 
347 #endif /* configSUPPORT_DYNAMIC_ALLOCATION */
348 /*-----------------------------------------------------------*/
349 
350 #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
351 
xStreamBufferGenericCreateStatic(size_t xBufferSizeBytes,size_t xTriggerLevelBytes,BaseType_t xIsMessageBuffer,uint8_t * const pucStreamBufferStorageArea,StaticStreamBuffer_t * const pxStaticStreamBuffer)352     StreamBufferHandle_t xStreamBufferGenericCreateStatic( size_t xBufferSizeBytes,
353                                                            size_t xTriggerLevelBytes,
354                                                            BaseType_t xIsMessageBuffer,
355                                                            uint8_t * const pucStreamBufferStorageArea,
356                                                            StaticStreamBuffer_t * const pxStaticStreamBuffer )
357     {
358         StreamBuffer_t * const pxStreamBuffer = ( StreamBuffer_t * ) pxStaticStreamBuffer; /*lint !e740 !e9087 Safe cast as StaticStreamBuffer_t is opaque Streambuffer_t. */
359         StreamBufferHandle_t xReturn;
360         uint8_t ucFlags;
361 
362         configASSERT( pucStreamBufferStorageArea );
363         configASSERT( pxStaticStreamBuffer );
364         configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
365 
366         /* A trigger level of 0 would cause a waiting task to unblock even when
367          * the buffer was empty. */
368         if( xTriggerLevelBytes == ( size_t ) 0 )
369         {
370             xTriggerLevelBytes = ( size_t ) 1;
371         }
372 
373         if( xIsMessageBuffer != pdFALSE )
374         {
375             /* Statically allocated message buffer. */
376             ucFlags = sbFLAGS_IS_MESSAGE_BUFFER | sbFLAGS_IS_STATICALLY_ALLOCATED;
377         }
378         else
379         {
380             /* Statically allocated stream buffer. */
381             ucFlags = sbFLAGS_IS_STATICALLY_ALLOCATED;
382         }
383 
384         /* In case the stream buffer is going to be used as a message buffer
385          * (that is, it will hold discrete messages with a little meta data that
386          * says how big the next message is) check the buffer will be large enough
387          * to hold at least one message. */
388         configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
389 
390         #if ( configASSERT_DEFINED == 1 )
391             {
392                 /* Sanity check that the size of the structure used to declare a
393                  * variable of type StaticStreamBuffer_t equals the size of the real
394                  * message buffer structure. */
395                 volatile size_t xSize = sizeof( StaticStreamBuffer_t );
396                 configASSERT( xSize == sizeof( StreamBuffer_t ) );
397             } /*lint !e529 xSize is referenced is configASSERT() is defined. */
398         #endif /* configASSERT_DEFINED */
399 
400         if( ( pucStreamBufferStorageArea != NULL ) && ( pxStaticStreamBuffer != NULL ) )
401         {
402             prvInitialiseNewStreamBuffer( pxStreamBuffer,
403                                           pucStreamBufferStorageArea,
404                                           xBufferSizeBytes,
405                                           xTriggerLevelBytes,
406                                           ucFlags );
407 
408             /* Remember this was statically allocated in case it is ever deleted
409              * again. */
410             pxStreamBuffer->ucFlags |= sbFLAGS_IS_STATICALLY_ALLOCATED;
411 
412             traceSTREAM_BUFFER_CREATE( pxStreamBuffer, xIsMessageBuffer );
413 
414             xReturn = ( StreamBufferHandle_t ) pxStaticStreamBuffer; /*lint !e9087 Data hiding requires cast to opaque type. */
415         }
416         else
417         {
418             xReturn = NULL;
419             traceSTREAM_BUFFER_CREATE_STATIC_FAILED( xReturn, xIsMessageBuffer );
420         }
421 
422         return xReturn;
423     }
424 
425 #endif /* ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
426 /*-----------------------------------------------------------*/
427 
vStreamBufferDelete(StreamBufferHandle_t xStreamBuffer)428 void vStreamBufferDelete( StreamBufferHandle_t xStreamBuffer )
429 {
430     StreamBuffer_t * pxStreamBuffer = xStreamBuffer;
431 
432     configASSERT( pxStreamBuffer );
433 
434     traceSTREAM_BUFFER_DELETE( xStreamBuffer );
435 
436     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_STATICALLY_ALLOCATED ) == ( uint8_t ) pdFALSE )
437     {
438         #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
439             {
440                 /* Both the structure and the buffer were allocated using a single call
441                 * to pvPortMalloc(), hence only one call to vPortFree() is required. */
442                 vPortFree( ( void * ) pxStreamBuffer ); /*lint !e9087 Standard free() semantics require void *, plus pxStreamBuffer was allocated by pvPortMalloc(). */
443             }
444         #else
445             {
446                 /* Should not be possible to get here, ucFlags must be corrupt.
447                  * Force an assert. */
448                 configASSERT( xStreamBuffer == ( StreamBufferHandle_t ) ~0 );
449             }
450         #endif
451     }
452     else
453     {
454         /* The structure and buffer were not allocated dynamically and cannot be
455          * freed - just scrub the structure so future use will assert. */
456         ( void ) memset( pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) );
457     }
458 }
459 /*-----------------------------------------------------------*/
460 
xStreamBufferReset(StreamBufferHandle_t xStreamBuffer)461 BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer )
462 {
463     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
464     BaseType_t xReturn = pdFAIL;
465 
466     #if ( configUSE_TRACE_FACILITY == 1 )
467         UBaseType_t uxStreamBufferNumber;
468     #endif
469 
470     configASSERT( pxStreamBuffer );
471 
472     #if ( configUSE_TRACE_FACILITY == 1 )
473         {
474             /* Store the stream buffer number so it can be restored after the
475              * reset. */
476             uxStreamBufferNumber = pxStreamBuffer->uxStreamBufferNumber;
477         }
478     #endif
479 
480     /* Can only reset a message buffer if there are no tasks blocked on it. */
481     taskENTER_CRITICAL();
482     {
483         if( pxStreamBuffer->xTaskWaitingToReceive == NULL )
484         {
485             if( pxStreamBuffer->xTaskWaitingToSend == NULL )
486             {
487                 #ifdef ESP_PLATFORM
488                     /* As we just entered a critical section, we must NOT reset the spinlock field.
489                      * Thus, call `prvResetStreamBufferFields` instead of `prvInitialiseNewStreamBuffer`
490                      */
491                     prvResetStreamBufferFields( pxStreamBuffer,
492                                                 pxStreamBuffer->pucBuffer,
493                                                 pxStreamBuffer->xLength,
494                                                 pxStreamBuffer->xTriggerLevelBytes,
495                                                 pxStreamBuffer->ucFlags );
496 
497                 #else  // ESP_PLATFORM
498                     prvInitialiseNewStreamBuffer( pxStreamBuffer,
499                                                   pxStreamBuffer->pucBuffer,
500                                                   pxStreamBuffer->xLength,
501                                                   pxStreamBuffer->xTriggerLevelBytes,
502                                                   pxStreamBuffer->ucFlags );
503                 #endif // ESP_PLATFORM
504                 xReturn = pdPASS;
505 
506                 #if ( configUSE_TRACE_FACILITY == 1 )
507                     {
508                         pxStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
509                     }
510                 #endif
511 
512                 traceSTREAM_BUFFER_RESET( xStreamBuffer );
513             }
514         }
515     }
516     taskEXIT_CRITICAL();
517 
518     return xReturn;
519 }
520 /*-----------------------------------------------------------*/
521 
xStreamBufferSetTriggerLevel(StreamBufferHandle_t xStreamBuffer,size_t xTriggerLevel)522 BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer,
523                                          size_t xTriggerLevel )
524 {
525     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
526     BaseType_t xReturn;
527 
528     configASSERT( pxStreamBuffer );
529 
530     /* It is not valid for the trigger level to be 0. */
531     if( xTriggerLevel == ( size_t ) 0 )
532     {
533         xTriggerLevel = ( size_t ) 1;
534     }
535 
536     /* The trigger level is the number of bytes that must be in the stream
537      * buffer before a task that is waiting for data is unblocked. */
538     if( xTriggerLevel <= pxStreamBuffer->xLength )
539     {
540         pxStreamBuffer->xTriggerLevelBytes = xTriggerLevel;
541         xReturn = pdPASS;
542     }
543     else
544     {
545         xReturn = pdFALSE;
546     }
547 
548     return xReturn;
549 }
550 /*-----------------------------------------------------------*/
551 
xStreamBufferSpacesAvailable(StreamBufferHandle_t xStreamBuffer)552 size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer )
553 {
554     const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
555     size_t xSpace;
556 
557     configASSERT( pxStreamBuffer );
558 
559     xSpace = pxStreamBuffer->xLength + pxStreamBuffer->xTail;
560     xSpace -= pxStreamBuffer->xHead;
561     xSpace -= ( size_t ) 1;
562 
563     if( xSpace >= pxStreamBuffer->xLength )
564     {
565         xSpace -= pxStreamBuffer->xLength;
566     }
567     else
568     {
569         mtCOVERAGE_TEST_MARKER();
570     }
571 
572     return xSpace;
573 }
574 /*-----------------------------------------------------------*/
575 
xStreamBufferBytesAvailable(StreamBufferHandle_t xStreamBuffer)576 size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer )
577 {
578     const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
579     size_t xReturn;
580 
581     configASSERT( pxStreamBuffer );
582 
583     xReturn = prvBytesInBuffer( pxStreamBuffer );
584     return xReturn;
585 }
586 /*-----------------------------------------------------------*/
587 
xStreamBufferSend(StreamBufferHandle_t xStreamBuffer,const void * pvTxData,size_t xDataLengthBytes,TickType_t xTicksToWait)588 size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer,
589                           const void * pvTxData,
590                           size_t xDataLengthBytes,
591                           TickType_t xTicksToWait )
592 {
593     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
594     size_t xReturn, xSpace = 0;
595     size_t xRequiredSpace = xDataLengthBytes;
596     TimeOut_t xTimeOut;
597     size_t xMaxReportedSpace = 0;
598 
599     configASSERT( pvTxData );
600     configASSERT( pxStreamBuffer );
601 
602     /* The maximum amount of space a stream buffer will ever report is its length
603      * minus 1. */
604     xMaxReportedSpace = pxStreamBuffer->xLength - ( size_t ) 1;
605 
606     /* This send function is used to write to both message buffers and stream
607      * buffers.  If this is a message buffer then the space needed must be
608      * increased by the amount of bytes needed to store the length of the
609      * message. */
610     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
611     {
612         xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
613 
614         /* Overflow? */
615         configASSERT( xRequiredSpace > xDataLengthBytes );
616 
617         /* If this is a message buffer then it must be possible to write the
618          * whole message. */
619         if( xRequiredSpace > xMaxReportedSpace )
620         {
621             /* The message would not fit even if the entire buffer was empty,
622              * so don't wait for space. */
623             xTicksToWait = ( TickType_t ) 0;
624         }
625         else
626         {
627             mtCOVERAGE_TEST_MARKER();
628         }
629     }
630     else
631     {
632         /* If this is a stream buffer then it is acceptable to write only part
633          * of the message to the buffer.  Cap the length to the total length of
634          * the buffer. */
635         if( xRequiredSpace > xMaxReportedSpace )
636         {
637             xRequiredSpace = xMaxReportedSpace;
638         }
639         else
640         {
641             mtCOVERAGE_TEST_MARKER();
642         }
643     }
644 
645     if( xTicksToWait != ( TickType_t ) 0 )
646     {
647         vTaskSetTimeOutState( &xTimeOut );
648 
649         do
650         {
651             /* Wait until the required number of bytes are free in the message
652              * buffer. */
653             taskENTER_CRITICAL();
654             {
655                 xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
656 
657                 if( xSpace < xRequiredSpace )
658                 {
659                     /* Clear notification state as going to wait for space. */
660                     ( void ) xTaskNotifyStateClear( NULL );
661 
662                     /* Should only be one writer. */
663                     configASSERT( pxStreamBuffer->xTaskWaitingToSend == NULL );
664                     pxStreamBuffer->xTaskWaitingToSend = xTaskGetCurrentTaskHandle();
665                 }
666                 else
667                 {
668                     taskEXIT_CRITICAL();
669                     break;
670                 }
671             }
672             taskEXIT_CRITICAL();
673 
674             traceBLOCKING_ON_STREAM_BUFFER_SEND( xStreamBuffer );
675             ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
676             pxStreamBuffer->xTaskWaitingToSend = NULL;
677         } while( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE );
678     }
679     else
680     {
681         mtCOVERAGE_TEST_MARKER();
682     }
683 
684     if( xSpace == ( size_t ) 0 )
685     {
686         xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
687     }
688     else
689     {
690         mtCOVERAGE_TEST_MARKER();
691     }
692 
693     xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
694 
695     if( xReturn > ( size_t ) 0 )
696     {
697         traceSTREAM_BUFFER_SEND( xStreamBuffer, xReturn );
698 
699         /* Was a task waiting for the data? */
700         if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
701         {
702             sbSEND_COMPLETED( pxStreamBuffer );
703         }
704         else
705         {
706             mtCOVERAGE_TEST_MARKER();
707         }
708     }
709     else
710     {
711         mtCOVERAGE_TEST_MARKER();
712         traceSTREAM_BUFFER_SEND_FAILED( xStreamBuffer );
713     }
714 
715     return xReturn;
716 }
717 /*-----------------------------------------------------------*/
718 
xStreamBufferSendFromISR(StreamBufferHandle_t xStreamBuffer,const void * pvTxData,size_t xDataLengthBytes,BaseType_t * const pxHigherPriorityTaskWoken)719 size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer,
720                                  const void * pvTxData,
721                                  size_t xDataLengthBytes,
722                                  BaseType_t * const pxHigherPriorityTaskWoken )
723 {
724     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
725     size_t xReturn, xSpace;
726     size_t xRequiredSpace = xDataLengthBytes;
727 
728     configASSERT( pvTxData );
729     configASSERT( pxStreamBuffer );
730 
731     /* This send function is used to write to both message buffers and stream
732      * buffers.  If this is a message buffer then the space needed must be
733      * increased by the amount of bytes needed to store the length of the
734      * message. */
735     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
736     {
737         xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
738     }
739     else
740     {
741         mtCOVERAGE_TEST_MARKER();
742     }
743 
744     xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
745     xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
746 
747     if( xReturn > ( size_t ) 0 )
748     {
749         /* Was a task waiting for the data? */
750         if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
751         {
752             sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
753         }
754         else
755         {
756             mtCOVERAGE_TEST_MARKER();
757         }
758     }
759     else
760     {
761         mtCOVERAGE_TEST_MARKER();
762     }
763 
764     traceSTREAM_BUFFER_SEND_FROM_ISR( xStreamBuffer, xReturn );
765 
766     return xReturn;
767 }
768 /*-----------------------------------------------------------*/
769 
prvWriteMessageToBuffer(StreamBuffer_t * const pxStreamBuffer,const void * pvTxData,size_t xDataLengthBytes,size_t xSpace,size_t xRequiredSpace)770 static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
771                                        const void * pvTxData,
772                                        size_t xDataLengthBytes,
773                                        size_t xSpace,
774                                        size_t xRequiredSpace )
775 {
776     BaseType_t xShouldWrite;
777     size_t xReturn;
778 
779     if( xSpace == ( size_t ) 0 )
780     {
781         /* Doesn't matter if this is a stream buffer or a message buffer, there
782          * is no space to write. */
783         xShouldWrite = pdFALSE;
784     }
785     else if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) == ( uint8_t ) 0 )
786     {
787         /* This is a stream buffer, as opposed to a message buffer, so writing a
788          * stream of bytes rather than discrete messages.  Write as many bytes as
789          * possible. */
790         xShouldWrite = pdTRUE;
791         xDataLengthBytes = configMIN( xDataLengthBytes, xSpace );
792     }
793     else if( xSpace >= xRequiredSpace )
794     {
795         /* This is a message buffer, as opposed to a stream buffer, and there
796          * is enough space to write both the message length and the message itself
797          * into the buffer.  Start by writing the length of the data, the data
798          * itself will be written later in this function. */
799         xShouldWrite = pdTRUE;
800         ( void ) prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) &( xDataLengthBytes ), sbBYTES_TO_STORE_MESSAGE_LENGTH );
801     }
802     else
803     {
804         /* There is space available, but not enough space. */
805         xShouldWrite = pdFALSE;
806     }
807 
808     if( xShouldWrite != pdFALSE )
809     {
810         /* Writes the data itself. */
811         xReturn = prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) pvTxData, xDataLengthBytes ); /*lint !e9079 Storage buffer is implemented as uint8_t for ease of sizing, alignment and access. */
812     }
813     else
814     {
815         xReturn = 0;
816     }
817 
818     return xReturn;
819 }
820 /*-----------------------------------------------------------*/
821 
xStreamBufferReceive(StreamBufferHandle_t xStreamBuffer,void * pvRxData,size_t xBufferLengthBytes,TickType_t xTicksToWait)822 size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer,
823                              void * pvRxData,
824                              size_t xBufferLengthBytes,
825                              TickType_t xTicksToWait )
826 {
827     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
828     size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
829 
830     configASSERT( pvRxData );
831     configASSERT( pxStreamBuffer );
832 
833     /* This receive function is used by both message buffers, which store
834      * discrete messages, and stream buffers, which store a continuous stream of
835      * bytes.  Discrete messages include an additional
836      * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
837      * message. */
838     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
839     {
840         xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
841     }
842     else
843     {
844         xBytesToStoreMessageLength = 0;
845     }
846 
847     if( xTicksToWait != ( TickType_t ) 0 )
848     {
849         /* Checking if there is data and clearing the notification state must be
850          * performed atomically. */
851         taskENTER_CRITICAL();
852         {
853             xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
854 
855             /* If this function was invoked by a message buffer read then
856              * xBytesToStoreMessageLength holds the number of bytes used to hold
857              * the length of the next discrete message.  If this function was
858              * invoked by a stream buffer read then xBytesToStoreMessageLength will
859              * be 0. */
860             if( xBytesAvailable <= xBytesToStoreMessageLength )
861             {
862                 /* Clear notification state as going to wait for data. */
863                 ( void ) xTaskNotifyStateClear( NULL );
864 
865                 /* Should only be one reader. */
866                 configASSERT( pxStreamBuffer->xTaskWaitingToReceive == NULL );
867                 pxStreamBuffer->xTaskWaitingToReceive = xTaskGetCurrentTaskHandle();
868             }
869             else
870             {
871                 mtCOVERAGE_TEST_MARKER();
872             }
873         }
874         taskEXIT_CRITICAL();
875 
876         if( xBytesAvailable <= xBytesToStoreMessageLength )
877         {
878             /* Wait for data to be available. */
879             traceBLOCKING_ON_STREAM_BUFFER_RECEIVE( xStreamBuffer );
880             ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
881             pxStreamBuffer->xTaskWaitingToReceive = NULL;
882 
883             /* Recheck the data available after blocking. */
884             xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
885         }
886         else
887         {
888             mtCOVERAGE_TEST_MARKER();
889         }
890     }
891     else
892     {
893         xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
894     }
895 
896     /* Whether receiving a discrete message (where xBytesToStoreMessageLength
897      * holds the number of bytes used to store the message length) or a stream of
898      * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
899      * available must be greater than xBytesToStoreMessageLength to be able to
900      * read bytes from the buffer. */
901     if( xBytesAvailable > xBytesToStoreMessageLength )
902     {
903         xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable, xBytesToStoreMessageLength );
904 
905         /* Was a task waiting for space in the buffer? */
906         if( xReceivedLength != ( size_t ) 0 )
907         {
908             traceSTREAM_BUFFER_RECEIVE( xStreamBuffer, xReceivedLength );
909             sbRECEIVE_COMPLETED( pxStreamBuffer );
910         }
911         else
912         {
913             mtCOVERAGE_TEST_MARKER();
914         }
915     }
916     else
917     {
918         traceSTREAM_BUFFER_RECEIVE_FAILED( xStreamBuffer );
919         mtCOVERAGE_TEST_MARKER();
920     }
921 
922     return xReceivedLength;
923 }
924 /*-----------------------------------------------------------*/
925 
xStreamBufferNextMessageLengthBytes(StreamBufferHandle_t xStreamBuffer)926 size_t xStreamBufferNextMessageLengthBytes( StreamBufferHandle_t xStreamBuffer )
927 {
928     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
929     size_t xReturn, xBytesAvailable, xOriginalTail;
930     configMESSAGE_BUFFER_LENGTH_TYPE xTempReturn;
931 
932     configASSERT( pxStreamBuffer );
933 
934     /* Ensure the stream buffer is being used as a message buffer. */
935     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
936     {
937         xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
938 
939         if( xBytesAvailable > sbBYTES_TO_STORE_MESSAGE_LENGTH )
940         {
941             /* The number of bytes available is greater than the number of bytes
942              * required to hold the length of the next message, so another message
943              * is available.  Return its length without removing the length bytes
944              * from the buffer.  A copy of the tail is stored so the buffer can be
945              * returned to its prior state as the message is not actually being
946              * removed from the buffer. */
947             xOriginalTail = pxStreamBuffer->xTail;
948             ( void ) prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempReturn, sbBYTES_TO_STORE_MESSAGE_LENGTH, xBytesAvailable );
949             xReturn = ( size_t ) xTempReturn;
950             pxStreamBuffer->xTail = xOriginalTail;
951         }
952         else
953         {
954             /* The minimum amount of bytes in a message buffer is
955              * ( sbBYTES_TO_STORE_MESSAGE_LENGTH + 1 ), so if xBytesAvailable is
956              * less than sbBYTES_TO_STORE_MESSAGE_LENGTH the only other valid
957              * value is 0. */
958             configASSERT( xBytesAvailable == 0 );
959             xReturn = 0;
960         }
961     }
962     else
963     {
964         xReturn = 0;
965     }
966 
967     return xReturn;
968 }
969 /*-----------------------------------------------------------*/
970 
xStreamBufferReceiveFromISR(StreamBufferHandle_t xStreamBuffer,void * pvRxData,size_t xBufferLengthBytes,BaseType_t * const pxHigherPriorityTaskWoken)971 size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer,
972                                     void * pvRxData,
973                                     size_t xBufferLengthBytes,
974                                     BaseType_t * const pxHigherPriorityTaskWoken )
975 {
976     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
977     size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
978 
979     configASSERT( pvRxData );
980     configASSERT( pxStreamBuffer );
981 
982     /* This receive function is used by both message buffers, which store
983      * discrete messages, and stream buffers, which store a continuous stream of
984      * bytes.  Discrete messages include an additional
985      * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
986      * message. */
987     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
988     {
989         xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
990     }
991     else
992     {
993         xBytesToStoreMessageLength = 0;
994     }
995 
996     xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
997 
998     /* Whether receiving a discrete message (where xBytesToStoreMessageLength
999      * holds the number of bytes used to store the message length) or a stream of
1000      * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
1001      * available must be greater than xBytesToStoreMessageLength to be able to
1002      * read bytes from the buffer. */
1003     if( xBytesAvailable > xBytesToStoreMessageLength )
1004     {
1005         xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable, xBytesToStoreMessageLength );
1006 
1007         /* Was a task waiting for space in the buffer? */
1008         if( xReceivedLength != ( size_t ) 0 )
1009         {
1010             sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
1011         }
1012         else
1013         {
1014             mtCOVERAGE_TEST_MARKER();
1015         }
1016     }
1017     else
1018     {
1019         mtCOVERAGE_TEST_MARKER();
1020     }
1021 
1022     traceSTREAM_BUFFER_RECEIVE_FROM_ISR( xStreamBuffer, xReceivedLength );
1023 
1024     return xReceivedLength;
1025 }
1026 /*-----------------------------------------------------------*/
1027 
prvReadMessageFromBuffer(StreamBuffer_t * pxStreamBuffer,void * pvRxData,size_t xBufferLengthBytes,size_t xBytesAvailable,size_t xBytesToStoreMessageLength)1028 static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
1029                                         void * pvRxData,
1030                                         size_t xBufferLengthBytes,
1031                                         size_t xBytesAvailable,
1032                                         size_t xBytesToStoreMessageLength )
1033 {
1034     size_t xOriginalTail, xReceivedLength, xNextMessageLength;
1035     configMESSAGE_BUFFER_LENGTH_TYPE xTempNextMessageLength;
1036 
1037     if( xBytesToStoreMessageLength != ( size_t ) 0 )
1038     {
1039         /* A discrete message is being received.  First receive the length
1040          * of the message.  A copy of the tail is stored so the buffer can be
1041          * returned to its prior state if the length of the message is too
1042          * large for the provided buffer. */
1043         xOriginalTail = pxStreamBuffer->xTail;
1044         ( void ) prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempNextMessageLength, xBytesToStoreMessageLength, xBytesAvailable );
1045         xNextMessageLength = ( size_t ) xTempNextMessageLength;
1046 
1047         /* Reduce the number of bytes available by the number of bytes just
1048          * read out. */
1049         xBytesAvailable -= xBytesToStoreMessageLength;
1050 
1051         /* Check there is enough space in the buffer provided by the
1052          * user. */
1053         if( xNextMessageLength > xBufferLengthBytes )
1054         {
1055             /* The user has provided insufficient space to read the message
1056              * so return the buffer to its previous state (so the length of
1057              * the message is in the buffer again). */
1058             pxStreamBuffer->xTail = xOriginalTail;
1059             xNextMessageLength = 0;
1060         }
1061         else
1062         {
1063             mtCOVERAGE_TEST_MARKER();
1064         }
1065     }
1066     else
1067     {
1068         /* A stream of bytes is being received (as opposed to a discrete
1069          * message), so read as many bytes as possible. */
1070         xNextMessageLength = xBufferLengthBytes;
1071     }
1072 
1073     /* Read the actual data. */
1074     xReceivedLength = prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) pvRxData, xNextMessageLength, xBytesAvailable ); /*lint !e9079 Data storage area is implemented as uint8_t array for ease of sizing, indexing and alignment. */
1075 
1076     return xReceivedLength;
1077 }
1078 /*-----------------------------------------------------------*/
1079 
xStreamBufferIsEmpty(StreamBufferHandle_t xStreamBuffer)1080 BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer )
1081 {
1082     const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
1083     BaseType_t xReturn;
1084     size_t xTail;
1085 
1086     configASSERT( pxStreamBuffer );
1087 
1088     /* True if no bytes are available. */
1089     xTail = pxStreamBuffer->xTail;
1090 
1091     if( pxStreamBuffer->xHead == xTail )
1092     {
1093         xReturn = pdTRUE;
1094     }
1095     else
1096     {
1097         xReturn = pdFALSE;
1098     }
1099 
1100     return xReturn;
1101 }
1102 /*-----------------------------------------------------------*/
1103 
xStreamBufferIsFull(StreamBufferHandle_t xStreamBuffer)1104 BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer )
1105 {
1106     BaseType_t xReturn;
1107     size_t xBytesToStoreMessageLength;
1108     const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
1109 
1110     configASSERT( pxStreamBuffer );
1111 
1112     /* This generic version of the receive function is used by both message
1113      * buffers, which store discrete messages, and stream buffers, which store a
1114      * continuous stream of bytes.  Discrete messages include an additional
1115      * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the message. */
1116     if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
1117     {
1118         xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
1119     }
1120     else
1121     {
1122         xBytesToStoreMessageLength = 0;
1123     }
1124 
1125     /* True if the available space equals zero. */
1126     if( xStreamBufferSpacesAvailable( xStreamBuffer ) <= xBytesToStoreMessageLength )
1127     {
1128         xReturn = pdTRUE;
1129     }
1130     else
1131     {
1132         xReturn = pdFALSE;
1133     }
1134 
1135     return xReturn;
1136 }
1137 /*-----------------------------------------------------------*/
1138 
xStreamBufferSendCompletedFromISR(StreamBufferHandle_t xStreamBuffer,BaseType_t * pxHigherPriorityTaskWoken)1139 BaseType_t xStreamBufferSendCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
1140                                               BaseType_t * pxHigherPriorityTaskWoken )
1141 {
1142     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
1143     BaseType_t xReturn;
1144     UBaseType_t uxSavedInterruptStatus;
1145 
1146     configASSERT( pxStreamBuffer );
1147 
1148     uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
1149     {
1150         if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )
1151         {
1152             ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive,
1153                                          ( uint32_t ) 0,
1154                                          eNoAction,
1155                                          pxHigherPriorityTaskWoken );
1156             ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;
1157             xReturn = pdTRUE;
1158         }
1159         else
1160         {
1161             xReturn = pdFALSE;
1162         }
1163     }
1164     portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1165 
1166     return xReturn;
1167 }
1168 /*-----------------------------------------------------------*/
1169 
xStreamBufferReceiveCompletedFromISR(StreamBufferHandle_t xStreamBuffer,BaseType_t * pxHigherPriorityTaskWoken)1170 BaseType_t xStreamBufferReceiveCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
1171                                                  BaseType_t * pxHigherPriorityTaskWoken )
1172 {
1173     StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
1174     BaseType_t xReturn;
1175     UBaseType_t uxSavedInterruptStatus;
1176 
1177     configASSERT( pxStreamBuffer );
1178 
1179     uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
1180     {
1181         if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )
1182         {
1183             ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend,
1184                                          ( uint32_t ) 0,
1185                                          eNoAction,
1186                                          pxHigherPriorityTaskWoken );
1187             ( pxStreamBuffer )->xTaskWaitingToSend = NULL;
1188             xReturn = pdTRUE;
1189         }
1190         else
1191         {
1192             xReturn = pdFALSE;
1193         }
1194     }
1195     portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1196 
1197     return xReturn;
1198 }
1199 /*-----------------------------------------------------------*/
1200 
prvWriteBytesToBuffer(StreamBuffer_t * const pxStreamBuffer,const uint8_t * pucData,size_t xCount)1201 static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
1202                                      const uint8_t * pucData,
1203                                      size_t xCount )
1204 {
1205     size_t xNextHead, xFirstLength;
1206 
1207     configASSERT( xCount > ( size_t ) 0 );
1208 
1209     xNextHead = pxStreamBuffer->xHead;
1210 
1211     /* Calculate the number of bytes that can be added in the first write -
1212      * which may be less than the total number of bytes that need to be added if
1213      * the buffer will wrap back to the beginning. */
1214     xFirstLength = configMIN( pxStreamBuffer->xLength - xNextHead, xCount );
1215 
1216     /* Write as many bytes as can be written in the first write. */
1217     configASSERT( ( xNextHead + xFirstLength ) <= pxStreamBuffer->xLength );
1218     ( void ) memcpy( ( void * ) ( &( pxStreamBuffer->pucBuffer[ xNextHead ] ) ), ( const void * ) pucData, xFirstLength ); /*lint !e9087 memcpy() requires void *. */
1219 
1220     /* If the number of bytes written was less than the number that could be
1221      * written in the first write... */
1222     if( xCount > xFirstLength )
1223     {
1224         /* ...then write the remaining bytes to the start of the buffer. */
1225         configASSERT( ( xCount - xFirstLength ) <= pxStreamBuffer->xLength );
1226         ( void ) memcpy( ( void * ) pxStreamBuffer->pucBuffer, ( const void * ) &( pucData[ xFirstLength ] ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
1227     }
1228     else
1229     {
1230         mtCOVERAGE_TEST_MARKER();
1231     }
1232 
1233     xNextHead += xCount;
1234 
1235     if( xNextHead >= pxStreamBuffer->xLength )
1236     {
1237         xNextHead -= pxStreamBuffer->xLength;
1238     }
1239     else
1240     {
1241         mtCOVERAGE_TEST_MARKER();
1242     }
1243 
1244     pxStreamBuffer->xHead = xNextHead;
1245 
1246     return xCount;
1247 }
1248 /*-----------------------------------------------------------*/
1249 
prvReadBytesFromBuffer(StreamBuffer_t * pxStreamBuffer,uint8_t * pucData,size_t xMaxCount,size_t xBytesAvailable)1250 static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
1251                                       uint8_t * pucData,
1252                                       size_t xMaxCount,
1253                                       size_t xBytesAvailable )
1254 {
1255     size_t xCount, xFirstLength, xNextTail;
1256 
1257     /* Use the minimum of the wanted bytes and the available bytes. */
1258     xCount = configMIN( xBytesAvailable, xMaxCount );
1259 
1260     if( xCount > ( size_t ) 0 )
1261     {
1262         xNextTail = pxStreamBuffer->xTail;
1263 
1264         /* Calculate the number of bytes that can be read - which may be
1265          * less than the number wanted if the data wraps around to the start of
1266          * the buffer. */
1267         xFirstLength = configMIN( pxStreamBuffer->xLength - xNextTail, xCount );
1268 
1269         /* Obtain the number of bytes it is possible to obtain in the first
1270          * read.  Asserts check bounds of read and write. */
1271         configASSERT( xFirstLength <= xMaxCount );
1272         configASSERT( ( xNextTail + xFirstLength ) <= pxStreamBuffer->xLength );
1273         ( void ) memcpy( ( void * ) pucData, ( const void * ) &( pxStreamBuffer->pucBuffer[ xNextTail ] ), xFirstLength ); /*lint !e9087 memcpy() requires void *. */
1274 
1275         /* If the total number of wanted bytes is greater than the number
1276          * that could be read in the first read... */
1277         if( xCount > xFirstLength )
1278         {
1279             /*...then read the remaining bytes from the start of the buffer. */
1280             configASSERT( xCount <= xMaxCount );
1281             ( void ) memcpy( ( void * ) &( pucData[ xFirstLength ] ), ( void * ) ( pxStreamBuffer->pucBuffer ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
1282         }
1283         else
1284         {
1285             mtCOVERAGE_TEST_MARKER();
1286         }
1287 
1288         /* Move the tail pointer to effectively remove the data read from
1289          * the buffer. */
1290         xNextTail += xCount;
1291 
1292         if( xNextTail >= pxStreamBuffer->xLength )
1293         {
1294             xNextTail -= pxStreamBuffer->xLength;
1295         }
1296 
1297         pxStreamBuffer->xTail = xNextTail;
1298     }
1299     else
1300     {
1301         mtCOVERAGE_TEST_MARKER();
1302     }
1303 
1304     return xCount;
1305 }
1306 /*-----------------------------------------------------------*/
1307 
prvBytesInBuffer(const StreamBuffer_t * const pxStreamBuffer)1308 static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer )
1309 {
1310 /* Returns the distance between xTail and xHead. */
1311     size_t xCount;
1312 
1313     xCount = pxStreamBuffer->xLength + pxStreamBuffer->xHead;
1314     xCount -= pxStreamBuffer->xTail;
1315 
1316     if( xCount >= pxStreamBuffer->xLength )
1317     {
1318         xCount -= pxStreamBuffer->xLength;
1319     }
1320     else
1321     {
1322         mtCOVERAGE_TEST_MARKER();
1323     }
1324 
1325     return xCount;
1326 }
1327 /*-----------------------------------------------------------*/
1328 
prvInitialiseNewStreamBuffer(StreamBuffer_t * const pxStreamBuffer,uint8_t * const pucBuffer,size_t xBufferSizeBytes,size_t xTriggerLevelBytes,uint8_t ucFlags)1329 static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
1330                                           uint8_t * const pucBuffer,
1331                                           size_t xBufferSizeBytes,
1332                                           size_t xTriggerLevelBytes,
1333                                           uint8_t ucFlags )
1334 {
1335     /* Assert here is deliberately writing to the entire buffer to ensure it can
1336      * be written to without generating exceptions, and is setting the buffer to a
1337      * known value to assist in development/debugging. */
1338     #if ( configASSERT_DEFINED == 1 )
1339         {
1340             /* The value written just has to be identifiable when looking at the
1341              * memory.  Don't use 0xA5 as that is the stack fill value and could
1342              * result in confusion as to what is actually being observed. */
1343             const BaseType_t xWriteValue = 0x55;
1344             configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer );
1345         } /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */
1346     #endif
1347 
1348     ( void ) memset( ( void * ) pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) ); /*lint !e9087 memset() requires void *. */
1349     pxStreamBuffer->pucBuffer = pucBuffer;
1350     pxStreamBuffer->xLength = xBufferSizeBytes;
1351     pxStreamBuffer->xTriggerLevelBytes = xTriggerLevelBytes;
1352     pxStreamBuffer->ucFlags = ucFlags;
1353 #ifdef ESP_PLATFORM
1354     portMUX_INITIALIZE( &pxStreamBuffer->xStreamBufferMux );
1355 #endif // ESP_PLATFORM
1356 }
1357 
1358 
1359 #ifdef ESP_PLATFORM
1360 
1361     /** The goal of this function is to (re)set all the fields of the given StreamBuffer, except
1362      * its lock.
1363      */
prvResetStreamBufferFields(StreamBuffer_t * const pxStreamBuffer,uint8_t * const pucBuffer,size_t xBufferSizeBytes,size_t xTriggerLevelBytes,uint8_t ucFlags)1364     static void prvResetStreamBufferFields( StreamBuffer_t * const pxStreamBuffer,
1365                                             uint8_t * const pucBuffer,
1366                                             size_t xBufferSizeBytes,
1367                                             size_t xTriggerLevelBytes,
1368                                             uint8_t ucFlags )
1369     {
1370         #if ( configASSERT_DEFINED == 1 )
1371             {
1372                 /* The value written just has to be identifiable when looking at the
1373                 * memory.  Don't use 0xA5 as that is the stack fill value and could
1374                 * result in confusion as to what is actually being observed. */
1375                 const BaseType_t xWriteValue = 0x55;
1376                 configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer );
1377             } /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */
1378         #endif
1379 
1380         /* Do not include the spinlock in the part to reset!
1381          * Thus, make sure the spinlock is the last field of the structure. */
1382         _Static_assert( offsetof(StreamBuffer_t, xStreamBufferMux) == sizeof( StreamBuffer_t ) - sizeof(portMUX_TYPE),
1383                         "xStreamBufferMux must be the last field of structure StreamBuffer_t" );
1384         const size_t erasable = sizeof( StreamBuffer_t ) - sizeof(portMUX_TYPE);
1385         ( void ) memset( ( void * ) pxStreamBuffer, 0x00, erasable ); /*lint !e9087 memset() requires void *. */
1386         pxStreamBuffer->pucBuffer = pucBuffer;
1387         pxStreamBuffer->xLength = xBufferSizeBytes;
1388         pxStreamBuffer->xTriggerLevelBytes = xTriggerLevelBytes;
1389         pxStreamBuffer->ucFlags = ucFlags;
1390     }
1391 
1392 #endif // ESP_PLATFORM
1393 
1394 
1395 #if ( configUSE_TRACE_FACILITY == 1 )
1396 
uxStreamBufferGetStreamBufferNumber(StreamBufferHandle_t xStreamBuffer)1397     UBaseType_t uxStreamBufferGetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer )
1398     {
1399         return xStreamBuffer->uxStreamBufferNumber;
1400     }
1401 
1402 #endif /* configUSE_TRACE_FACILITY */
1403 /*-----------------------------------------------------------*/
1404 
1405 #if ( configUSE_TRACE_FACILITY == 1 )
1406 
vStreamBufferSetStreamBufferNumber(StreamBufferHandle_t xStreamBuffer,UBaseType_t uxStreamBufferNumber)1407     void vStreamBufferSetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer,
1408                                              UBaseType_t uxStreamBufferNumber )
1409     {
1410         xStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
1411     }
1412 
1413 #endif /* configUSE_TRACE_FACILITY */
1414 /*-----------------------------------------------------------*/
1415 
1416 #if ( configUSE_TRACE_FACILITY == 1 )
1417 
ucStreamBufferGetStreamBufferType(StreamBufferHandle_t xStreamBuffer)1418     uint8_t ucStreamBufferGetStreamBufferType( StreamBufferHandle_t xStreamBuffer )
1419     {
1420         return( xStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER );
1421     }
1422 
1423 #endif /* configUSE_TRACE_FACILITY */
1424 /*-----------------------------------------------------------*/
1425