windows argv to string module utility (#28970)

* windows argv to string module utility

* rebased PR with latest devel branch

lib/ansible/module_utils/powershell/Ansible.ModuleUtils.ArgvParser.psm1

@@ -0,0 +1,75 @@
+# Copyright (c) 2017 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+# The rules used in these functions are derived from the below
+# https://docs.microsoft.com/en-us/cpp/cpp/parsing-cpp-command-line-arguments
+# https://blogs.msdn.microsoft.com/twistylittlepassagesallalike/2011/04/23/everyone-quotes-command-line-arguments-the-wrong-way/
+
+Function Escape-Argument($argument, $force_quote=$false) {
+    # this converts a single argument to an escaped version, use Join-Arguments
+    # instead of this function as this only escapes a single string.
+
+    # check if argument contains a space, \n, \t, \v or "
+    if ($force_quote -eq $false -and $argument.Length -gt 0 -and $argument -notmatch "[ \n\t\v`"]") {
+        # argument does not need escaping (and we don't want to force it),
+        # return as is
+        return $argument
+    } else {
+        # we need to quote the arg so start with "
+        $new_argument = '"'
+
+        for ($i = 0; $i -lt $argument.Length; $i++) {
+            $num_backslashes = 0
+
+            # get the number of \ from current char until end or not a \
+            while ($i -ne ($argument.Length - 1) -and $argument[$i] -eq "\") {
+                $num_backslashes++
+                $i++
+            }
+
+            $current_char = $argument[$i]
+            if ($i -eq ($argument.Length -1) -and $current_char -eq "\") {
+                # We are at the end of the string so we need to add the same \
+                # * 2 as the end char would be a "
+                $new_argument += ("\" * ($num_backslashes + 1) * 2)
+            } elseif ($current_char -eq '"') {
+                # we have a inline ", we need to add the existing \ but * by 2
+                # plus another 1
+                $new_argument += ("\" * (($num_backslashes * 2) + 1))
+                $new_argument += $current_char
+            } else {
+                # normal character so no need to escape the \ we have counted
+                $new_argument += ("\" * $num_backslashes)
+                $new_argument += $current_char
+            }
+        }
+
+        # we need to close the special arg with a "
+        $new_argument += '"'
+        return $new_argument
+    }
+}
+
+Function Argv-ToString($arguments, $force_quote=$false) {
+    # Takes in a list of un escaped arguments and convert it to a single string
+    # that can be used when starting a new process. It will escape the
+    # characters as necessary in the list.
+    # While there is a CommandLineToArgvW function there is a no
+    # ArgvToCommandLineW that we can call to convert a list to an escaped
+    # string.
+    # You can also pass in force_quote so that each argument is quoted even
+    # when not necessary, by default only arguments with certain characters are
+    # quoted.
+    # TODO: add in another switch which will escape the args for cmd.exe
+
+    $escaped_arguments = @()
+    foreach ($argument in $arguments) {
+        $escaped_argument = Escape-Argument -argument $argument -force_quote $force_quote
+        $escaped_arguments += $escaped_argument
+    }
+
+    return ($escaped_arguments -join ' ')
+}
+
+# this line must stay at the bottom to ensure all defined module parts are exported
+Export-ModuleMember -Alias * -Function * -Cmdlet *