[Bugfix] Improve consistency in getgateway.h

[TzviPM]

Description

• change the file name of getgateway.c to getgateway.m for consistency (Note*: all C is valid Objective C)
• add include of <netinet/in.h> to getgateway.h as it contains definition for in_addr_h
  • Note: without this, if a build system tries to include getgateway.h before <netinet/in.h>, then in_addr_t will not be defined.

Related Issues

AFAIK, no explicit bugs exist for these changes

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated the version in pubspec.yaml and CHANGELOG.md.
• I updated/added relevant documentation (doc comments with ///).
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Breaking Change

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• Yes, this is a breaking change (please indicate a breaking change in CHANGELOG.md and increment major revision).
• No, this is not a breaking change.

[TzviPM]

@miquelbeltran are you the right person to review this? I'm not sure how to request a review, but this PR should be ready for one.

The failing check for code coverage seems irrelevant in this case, since I didn't really add any new code per say.

[miquelbeltran]

Thanks! Potentially is all good, but I need to build and run at least once before approving and merging.

[TzviPM]

I think this actually can't be merged as is. The getgateway.c file was copied from a stack overflow in 2015, which was released under a CC BY-SA 3.0 license.

Changing the file requires updating the header to specify that we made changes, linking to the license, and releasing our changes under the same license. I'm not sure how the current BSD license would have to be updated to exclude this file either.

I have asked the author if they would publish a github gist with the code and specify a more permissive license.

[miquelbeltran]

Thanks for checking! I made a comment about removing the header, but then I realized that the header was in the original file, so I removed my comment. I'm fine to keep the header as it is, or add the changes as you say.

[TzviPM]

to better track this: https://stackoverflow.com/a/29440193/2679603

[TzviPM]

Tracking issue: #1058. I will close this PR for now as it will not be mergeable with the current licensing issues.