What are the steps involved in porting an Arduino library? I want to use the Adafruit CC3000 and its Arduino libraries on another platform. In this case it's the Arduino pin compatible PSOC4 Pioneer Kit. This is an ARM Cortex M0 based platform.

My question is: How would I go about porting a library like this? What are the steps, key files etc?

One obvious issue is that PSOC Creator does not readily support C++.

One positive might be that the Arduino Due board is based on the Atmel SAM3X8E ARM Cortex-M3 CPU.

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I did essentially the same thing with getting the Adafruit ST7735 library working in chipKIT. I started a support thread here which can lead you through my process.

I tackled it the same way I do general programming:
1-» Copy over Libraries, get it so your compiler can actually SEE them.
2-» Start trying to compile and then triage errors from the "top level" down:
3-» Look for stlib functions you recognize as should be working and fix those.
4-» Look for AVR specific code and comment those out. I normally also add my initials and a comment: ckck - bitbanging SPI, so I can search for these later.
Repeat 3 and 4 until it works or you quit. :)

Reach out to the forums for your target; they might have been there done that -- or like in my case, you introduce them to something that they want, so they dive in and help.