Fix prvWriteMessageToBuffer on big endian (#391)

prvWriteMessageToBuffer wrote the first sbBYTES_TO_STORE_MESSAGE_LENGTH
bytes of the size_t-typed length to the buffer as the data length. While
this functions on little endian, it copies the wrong bytes on big
endian. This fix converts the length to configMESSAGE_BUFFER_LENGTH_TYPE
first, and then copies the exact amount, thus fixing the issue.
Additionally it adds an assert to verify the size is not greater than
the max value of configMESSAGE_BUFFER_LENGTH_TYPE; previously this would
truncate silently.

Co-authored-by: Gaurav-Aggarwal-AWS <>
1 file changed
tree: 8bfe1fd24b43f97b32dbae170c4e34b175dab4a2
  1. .github/
  2. .gitmodules
  3. GitHub-FreeRTOS-Kernel-Home.url
  4. History.txt
  6. Quick_Start_Guide.url
  8. croutine.c
  9. event_groups.c
  10. include/
  11. list.c
  12. portable/
  13. queue.c
  14. stream_buffer.c
  15. tasks.c
  16. timers.c

Getting started

This repository contains FreeRTOS kernel source/header files and kernel ports only. This repository is referenced as a submodule in FreeRTOS/FreeRTOS repository, which contains pre-configured demo application projects under FreeRTOS/Demo directory.

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Additionally, for FreeRTOS kernel feature information refer to the Developer Documentation, and API Reference.

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  • The root of this repository contains the three files that are common to every port - list.c, queue.c and tasks.c. The kernel is contained within these three files. croutine.c implements the optional co-routine functionality - which is normally only used on very memory limited systems.

  • The ./portable directory contains the files that are specific to a particular microcontroller and/or compiler. See the readme file in the ./portable directory for more information.

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