wrapper SDFS.info(FSInfo& info) is overflowed for SD Cards > 4GB

[luc-github]

Basic Infos

• [ x] This issue complies with the issue POLICY doc.
• [ x] I have read the documentation at readthedocs and the issue is not addressed there.
• [x ] I have tested that the issue is present in current master branch (aka latest git).
• [x ] I have searched the issue tracker for a similar issue.
• [ x] If there is a stack dump, I have decoded it.
• [x ] I have filled out all fields below.

Platform

• Hardware: ESP-12
• Core Version: latest git / 2.5.1
• Development Env: Arduino IDE
• Operating System: Windows

Settings in IDE

• Module: Generic ESP8266 Module
• Flash Mode: dio
• Flash Size: 4MB
• lwip Variant: v2 Lower Memory
• Reset Method: ck
• Flash Frequency: 40Mhz
• CPU Frequency: 160MHz
• Upload Using: SERIAL
• Upload Speed: 115200

Because storage is using size_t instead of uint64_t so size over 4GB are incorrects
size_t is ok for SPIFFS, which is the original usage for info(FSInfo& info), but now if used on SD in must be uint64_t for SD, but this may lead to some others compatibilities issues if used on SPIFFS, because lot of functions currently use size_t and several others does not support uint64_t.

FYR On ESP32 the struct usage originaly done to add additional parameters in transparent way was dropped to use independant functions instead, each one using proper type :
SPIFFS:

class SPIFFSFS : public FS
{
...
    size_t totalBytes();
    size_t usedBytes();

For SDFS:

class SDFS : 
....
sdcard_type_t cardType();
uint64_t cardSize();
uint64_t totalBytes();
uint64_t usedBytes();

Sorry I do not have solution to offer because this issue need a mitigation between compatibility and features.
But I hope it give clear base description to help for a decision.

[earlephilhower]

I see two options:
. fsinfo64 (and make fsinfo entries return min(MAX_SIZE_T, fsinfo64().field)`
. No need to preserve binary size/ABI, only source, so change them to uint64_t

@d-a-v, @devyte, thoughts?