[FEAT] Add net module in lib_ccxr

[elbertronnie]

In raising this pull request, I confirm the following (please check boxes):

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This is an attempt to split #1495 into multiple independant PRs. Dependant on #1551, #1556 and #1553.

This PR adds networking primitives to send and receive captions across the internet. The networking functions are integrated into C codebase.

NOTE: I was able to test the TCP implementation but I could check if the UDP implementation is correct or not, since there is no way to send caption through UDP.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results:

Report Name	Tests Passed
Broken	13/13
CEA-708	2/14
DVB	4/7
DVD	3/3
DVR-MS	2/2
General	24/27
Hauppage	3/3
MP4	2/3
NoCC	10/10
Options	72/87
Teletext	21/21
WTV	9/13
XDS	26/34

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Your PR breaks these cases:

• ccextractor -autoprogram -out=srt -latin1 85271be4d2..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 1974a299f0..., Last passed: Never
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• ccextractor -svc all da904de35d..., Last passed: Never
• ccextractor -svc all[EUC-KR] b5d6aad89f..., Last passed: Never
• ccextractor -svc 1,2[UTF-8],3[EUC-KR],54 -out=txt da904de35d..., Last passed: Never
• ccextractor -autoprogram -out=srt -latin1 -1 a65d39ccb3..., Last passed: Never
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• ccextractor -stdout -quiet -nofc 79a51f3500..., Last passed: Never
• ccextractor -stdout -quiet -nofc 767b546f96..., Last passed: Never

Check the result page for more info.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results:

Report Name	Tests Passed
Broken	13/13
CEA-708	2/14
DVB	4/7
DVD	3/3
DVR-MS	2/2
General	24/27
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	85/87
Teletext	21/21
WTV	13/13
XDS	30/34

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Your PR breaks these cases:

• ccextractor -autoprogram -out=srt -latin1 85271be4d2..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 1974a299f0..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 132d7df7e9..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 99e5eaafdc..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -xds -latin1 -ucla e274a73653..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 -ucla -xds b22260d065..., Last passed: Never
• ccextractor -autoprogram -out=srt -latin1 -ucla c8dc039a88..., Last passed: Never
• ccextractor -autoprogram -out=ttxt -latin1 -ucla -xds 88cd42b89a..., Last passed: Never
• ccextractor -svc 1 -out=txt -nobom -noru ea83ff7bcb..., Last passed: Never
• ccextractor -svc 1 -out=txt f17524b53f..., Last passed: Never
• ccextractor -svc 1 -out=txt 80848c45f8..., Last passed: Never
• ccextractor -svc 1 -out=txt -nobom -noru b5d6aad89f..., Last passed: Never
• ccextractor -svc 1[EUC-KR] -out=txt -noru b5d6aad89f..., Last passed: Never
• ccextractor -svc 1 -out=srt da904de35d..., Last passed: Never
• ccextractor -svc 1 -out=sami da904de35d..., Last passed: Never
• ccextractor -svc 1[EUC-KR] b5d6aad89f..., Last passed: Never
• ccextractor -svc 1[EUC-KR] -noru b5d6aad89f..., Last passed: Never
• ccextractor -svc all da904de35d..., Last passed: Never
• ccextractor -svc all[EUC-KR] b5d6aad89f..., Last passed: Never
• ccextractor -svc 1,2[UTF-8],3[EUC-KR],54 -out=txt da904de35d..., Last passed: Never
• ccextractor -svc 1 c83f765c66..., Last passed: Never
• ccextractor --capfile /repository/Dictionary/MattS_dictionary.txt c83f765c66..., Last passed: Never
• ccextractor -stdout -quiet -nofc 79a51f3500..., Last passed: Never
• ccextractor -stdout -quiet -nofc 767b546f96..., Last passed: Never

Check the result page for more info.

[IshanGrover2004]

data.extend_from_slice("\0".as_bytes());

Is this necessary?? @elbertronnie

[IshanGrover2004]

Is this because C code uses memcpy. But still is this really needed?

[elbertronnie]

t = 1;
if (title != NULL)
    t += strlen(title);

// ------- other code -------

if (title != NULL)
    memcpy(end, title, t);
end += t;

Yes, because memcpy will also also copy the NUL character. This is necessary, otherwise how will the program know where one string starts and other ends. You are not passing the length of each string anyway.

[elbertronnie]

And I was busy for the past week, I will probably review both your PRs tomorrow or day after tomorrow.