Fix gzip help text

[DL6ER]

What does this implement/fix?

The previously described flags --compress and --uncompress never existed.

New help text:

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Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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[DL6ER]

The corresponding code is here:

FTL/src/args.c

Lines 215 to 266 in 3b1aebd

	// Compression feature
	if((argc == 3 || argc == 4) &&
	(strcmp(argv[1], "gzip") == 0 || strcmp(argv[1], "--gzip") == 0))
	{
	// Enable stdout printing
	cli_mode = true;
	log_ctrl(false, true);
	// Get input and output file names
	const char *infile = argv[2];
	bool is_gz = strEndsWith(infile, ".gz");
	char *outfile = NULL;
	if(argc == 4)
	{
	// If an output file is given, we use it
	outfile = strdup(argv[3]);
	}
	else if(is_gz)
	{
	// If no output file is given, and this is a gzipped
	// file, we use the input file name without ".gz"
	// appended
	outfile = calloc(strlen(infile)-2, sizeof(char));
	memcpy(outfile, infile, strlen(infile)-3);
	}
	else
	{
	// If no output file is given, and this is not a gzipped
	// file, we use the input file name with ".gz" appended
	outfile = calloc(strlen(infile)+4, sizeof(char));
	strcpy(outfile, infile);
	strcat(outfile, ".gz");
	}
	bool success = false;
	if(is_gz)
	{
	// If the input file is already gzipped, we decompress it
	success = inflate_file(infile, outfile, true);
	}
	else
	{
	// If the input file is not gzipped, we compress it
	success = deflate_file(infile, outfile, true);
	}
	// Free allocated memory
	free(outfile);
	// Return exit code
	exit(success ? EXIT_SUCCESS : EXIT_FAILURE);
	}

[yubiuser]

I understand the changed help text, but it required a lot of mental energy. The whole reason for the change is

The previously described flags --compress and --uncompress never existed.

I'd like to suggest to implement them. This would make the handling way more intuitive and does not require to think around the corner.

pihole-FTL --gzip --compress file.txt --> file.txt.gz
pihole-FTL --gzip --compress file.txt out.gt--> out.gz
pihole-FTL --gzip --compress file.gz --> error/or file.gz.gz
pihole-FTL --gzip --uncompress file.txt.gz --> file.txt
pihole-FTL --gzip --uncompress file.txt --> error
pihole-FTL --gzip file.txt --> error
pihole-FTL --gzip file.gz --> error

[DL6ER]

Sometimes - actually quite often - less is more.

I would like to avoid introducing additional flags because shorter always seems to be better on the CLI. Of course, this is only true if understandability isn't decreased by this brevity. But I don't really think it's the case here. How about instead of describing its precisely, we instead only provide the examples and let them speak for themselves?

Like

[yubiuser]

Your suggestion sounds good. The text is short and easy to understand.