Can't use spiram.h functions when building with cpp. (IDFGH-4861)

[mongonta0716]

Functions in spiram.h cannot be used when built with cpp because extern "C" is not defined in spiram.h.

[CLAassistant]

All committers have signed the CLA.

[Alvin1Zhang]

Thanks for your contribution.

[ginkgm]

Hi @mongonta0716 ,

Thanks for your contribution!

Generally speaking, it's non-public API, so we don't suggest you use that header directly, and haven't add CPP guard for it. But since you have your use case, we will accept this.

[mongonta0716]

Hi @ginkgm ,Thanks for your reply.

I noticed this API while doing research on devices with 8MB of PSRAM. I'm sorry I didn't know it was non-public.

Is there any other API to know the total amount of PSRAM?

[igrr]

Hi @mongonta0716, thank you for the PR. Your fix has been cherry-picked as 897496d with a subsequent commit applying similar fix for other chips. esp_spiram_get_chip_size function indeed looks like the correct one to use for the purpose you have mentioned.