FreeRTOS port

[Joel Bodenmann]

We'd welcome any feedback and bug fixes for the FreeRTOS support that is now part of the master branch and therefore the upcoming 2.1 release.

~ Tectu

[m_b]

I am currently running uGFX (git download from 2014/07/31) with FreeRTOS (v7.3.0) on an Altera NiosII target platform (gcc v4.5.3) with a framebuffer display driver.

My problems were:

• freertos.h files in src\gos\gos module conflicted the original FreeRTOS.h file. I renamed them to freertos_gfx.h/c
  
• Missing type definitions in freertos_gfx.h such as, int8_t, uint8_t, etc. This might work on other platforms without modifications?
  
• freertos_gfx.c: renamed portTICK_PERIOD_MS to portTICK_RATE_MS. Again, this might be a platform/port/version issue.

[Joel Bodenmann]

Thank you very much for your feedback.

We are aware of the conflicting file names on a case insensitive operating system since a short while. The changes have been made but not yet tested and pushed. We will push a fix to the repository this evening (GTM+01:00).

About the definitions: Which FreeRTOS version are you using? We have tested with FreeRTOS 8.x without any problems so far. Neither did any user report a conflict there.

~ Tectu

[m_b]

I am running FreeRTOS v7.3.0.

A quick look-up on the FreeRTOS homepage might give an explanation:

http://www.freertos.org/upgrading-to-FreeRTOS-V8.html#stdint

[Joel Bodenmann]

Thank you for the link. We'll take a look if it's possible to make the types conditional by reading out the FreeRTOS version (is there such a macro?) at compile time. We are doing the same to support ChibiOS/RT 2.x and 3.x in the same way.

~ Tectu

[m_b]

Yes there is (defined in task.h)

Before FreeRTOS 8.x.x

#define tskKERNEL_VERSION_NUMBER "V7.3.0"

From FreeRTOS 8.x.x on

#define tskKERNEL_VERSION_NUMBER "V8.0.1"
#define tskKERNEL_VERSION_MAJOR 8
#define tskKERNEL_VERSION_MINOR 0
#define tskKERNEL_VERSION_BUILD 1

[Joel Bodenmann]

Too bad that they don't have separate macros for each individual digit before 8.x.

I don't know FreeRTOS that well, what do you think about this?

#if tskKERNEL_VERSION_MAJOR == 8
   /* Types for 8.x */
#else
   /* Types for 7.x (and lower?) */

I assume taht this should work as the tskKERNEL_VERSION_MAJOR macro should not be implemented at all at any < 8.x release.

~ Tectu

[m_b]

Yes that should work.

[steved]

Too bad that they don't have separate macros for each individual digit before 8.x.

#if tskKERNEL_VERSION_MAJOR == 8
   /* Types for 8.x */
#else
   /* Types for 7.x (and lower?) */

I assume taht this should work as the tskKERNEL_VERSION_MAJOR macro should not be implemented at all at any < 8.x release.

~ Tectu

Are undefined preprocessor symbols handled consistently across compilers?

Defensive coding might suggest:

#ifdef tskKERNEL_VERSION_MAJOR
#if tskKERNEL_VERSION_MAJOR == 8
   /* Types for 8.x */
#else
   /* Types for 7.x (and lower?) */
#endif
#else
   /* Types for 7.x (and lower?) */
#endif

[Joel Bodenmann]

Are undefined preprocessor symbols handled consistently across compilers?

I'm not sure, that's why I am asking ;-)

Thank you for your suggestion. Looks like a safe way to go.

~ Tectu

[inmarket]

The c standard says that undefined macro variables if used in an expression will evaluate as 0.

Not all compilers always follow the rules though.

Try...

#if defined (var) && var == 8

[Joel Bodenmann]

We have added the missing type definitions for the FreeRTOS 7.x versions: https://bitbucket.org/Tectu/ugfx/commit ... cabe37a83a

Can you please make sure that everything compiles fine?

~ Tectu

[Joel Bodenmann]

We also renamed the FreeRTOS files to avoid file name conflicts on case insensitive systems: https://bitbucket.org/Tectu/ugfx/commit ... e619ac333f

~ Tectu