Re: [PATCH v2 1/3] kernel-shark: Provide parsing for quotation marks in Record command line

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 18 Sep 2019 17:23:17 +0300
"Yordan Karadzhov (VMware)" <y.karadz@gmail.com> wrote:

> +/**
> + * Separate the command line arguments inside the string taking into account
> + * possible shell quoting and new lines.
> + */
> +QStringList splitArguments(QString cmd)
> +{
> +	QString::SplitBehavior opt = QString::SkipEmptyParts;
> +	int i, progress = 0, size;
> +	QStringList argv;
> +	QChar quote = 0;
> +
> +	/* Remove all new lines. */
> +	cmd.replace("\\\n", " ");
> +
> +	size = cmd.count();
> +	auto lamMid = [&] () {return cmd.mid(progress, i - progress);};
> +	for (i = 0; i < size; ++i) {
> +		if (cmd[i] == '\\') {
> +			cmd.remove(i, 1);
> +			size --;
> +			continue;
> +		}
> +
> +		if (cmd[i] == '\'' || cmd[i] == '"') {
> +			if (quote.isNull()) {
> +				argv << lamMid().split(" ", opt);
> +				quote = cmd[i++];
> +				progress = i;
> +			} else if (quote == cmd[i]) {
> +				argv << lamMid();
> +				quote = 0;
> +				progress = ++i;
> +			}
> +		}
> +	}
> +
> +	argv << cmd.right(size - progress).split(" ", opt);
> +
> +	return argv;
> +}

I still find the above hard to read, but so be it ;-) 

Anyway, not quite yet. I just noticed that if I do:

  echo "this \" is \" a \"test"

The output has:

("echo", "this \" is \" a \"test")


We don't want to keep the backslash here. We want to remove it before
passing it as an argument.

The above should be:

("echo", "this " is " a "test")

(thinking that you put in the outside quotes. In other words, if I have:

 echo "hello \"there\""

We should break that up into: 
  arg0=echo
  arg1=hello "there"

-- Steve