Polish API `char*` vs. `unsigned char*`

[sjaeckel]

e.g. the Base64 API uses unsigned char* where char* should have been used.

Check all API's that work with "strings" and correct this.

[karel-m]

The only issue I see with char* case is the fact that some people may assume that char* means passing/returning a string with NUL byte at the end, which is not our current behaviour.

For example libsodium adds NUL byte when encoding B64/HEX - https://download.libsodium.org/doc/helpers/

[sjaeckel]

passing/returning a string with NUL byte at the end, which is not our current behaviour.

well that's only true for our decoders, the encoders already NUL-terminate the output...

[karel-m]

You are right base64_encode and base64url_encode do append NUL byte; however, base32_encode does not (it should at least for consistency).

Decoders are IMO not a problem.

[sjaeckel]

base32_encode does not

yeah, it should! you can add it to #353 if you want to :)

Decoders are IMO not a problem.

nope, but I'd say either we change the existing API or we add base64_decode_str() etc. (which I'd prefer as the existing API has also its valid use-cases)

[karel-m]

yeah, it should! you can add it to #353 if you want to :)

I think #353 seems like ready to merge, I'd fix it in a separate PR. I also plan to suggest a small change to base64_decode where the relaxed mode seems to be more relaxed than it should be.

[sjaeckel]

I also plan to suggest a small change to base64_decode where the relaxed mode seems to be more relaxed than it should be.

oh kay... now I'm curious :)

[karel-m]

@sjaeckel do you see any troubles with switching to use 'char*' in base64_* ?

[sjaeckel]

@sjaeckel do you see any troubles with switching to use 'char*' in base64_* ?

not really

[karel-m]

FYI: there are two related PR #366 and #367

I would like to propose changing:

int base16_decode(const char *in, unsigned char *out, unsigned long *outlen)

to:

int base16_decode(const char *in, unsigned long inlen, unsigned char *out, unsigned long *outlen)

It will be consistent with base64_encode and base32_encode and IMO it is also a bit more developer-friendly as you do not need to safe-check in buffer before calling base16_decode.