Improving Error Handling: Missing PARTIAL_FILE and long switch-case refactoring

[laxerhd]

Description

While taking a look at error.h, I noticed that the ErrorCode enum entry PARTIAL_FILE is not used in the error.cpp switch statement. Is this intended?

I also wanted to ask if there was any specific reason for including CURLE_OBSOLETE46 while not adding the other obsolete cURL error codes? Are the others related to unsupported protocols?

PARTIAL_FILE and CURLE_OBSOLETE46 were both added in this commit when adding better cpr error codes in september.

Additionally error.cpp looks kind of scarry with its 200-line switch-case statement. I was wondering if using an unordered_map instead of the switch-case statement might make the code a bit more readable and easier to maintain.

For example:

static const std::unordered_map<std::int32_t, ErrorCode> curl_error_map = {
    {CURLE_OK, ErrorCode::OK},
    {CURLE_UNSUPPORTED_PROTOCOL, ErrorCode::UNSUPPORTED_PROTOCOL},
    // -- AND FOR ERROR CODES ONLY SUPPORTED IN SPECIFIC LIBCURL_VERSION --
#if LIBCURL_VERSION_NUM >= 0x074E00
    {CURLE_SETOPT_OPTION_SYNTAX, ErrorCode::SETOPT_OPTION_SYNTAX},
#endif
    ...
}

Example/How to Reproduce

Files to take a look at: error.cpp and error.h as well as this commit

Possible Fix

1. Adding PARTIAL_FILE-case to error.cpp
2. Include/Remove obsolete error codes for consistency
3. Refactor errror.cpp to use map instead of a switch-case

Where did you get it from?

GitHub (branch e.g. master)

Additional Context/Your Environment

• OS: -
• Version: -

[COM8]

@laxerhd thanks for bringing this to my attention.

• PARTIAL_FILE you are right. This is missing. It should map to CURLE_PARTIAL_FILE which was added in curl 7.1
• CURLE_OBSOLETE46 can be removed. There is no reason to include it.
• Map based approach: Yes! I really like this approach.

Would you like to create a PR for it?

[laxerhd]

Yeah, I can do that!