Zephyr builder: Add escaping for the 'vars' parameter

Fix the issue with passing the "vars" parameters from the configuration
moulin YAML file to the build.ninja context.

The 'vars' parameter of the Zephyr builder is placed into the bash -c
"... cmd ..." context. It requires an additional level of escaping to
be added to the 'vars' parameter.

But that is not enough. The 'vars' parameter is passed to the 'west
build' call. West, in turn, passes those 'vars' parameter to CMake.

On the CMake level, Zephyr splits all incoming CMake parameters into 2
parts:

1. Those, which start with the "CONFIG_" prefix
2. All the others

The first group of parameters is stored in the KConfig file. When users
pass a string to Kconfig through CMake, they are expected to pass it so
that quotes are correct seen from Kconfig, that is:

> cmake -DCONFIG_A_STRING=\"foo bar\"

In this case, to obtain the required level of escaping:

- the first group of parameters should be additionally escaped twice on
the moulin level
- the second group of parameters should be additionally escaped once on
the moulin level

As a result of this patch, the user can specify the 'vars' on the yaml
level in the following way:

        vars:
          - "CONFIG_KERNEL_BIN_NAME=\"%{KERNEL_BIN_NAME}\""
          - "MY_VARIABLE=\"1234567890\""

Signed-off-by: Mykhailo Androsiuk <[email protected]>

moulin/builders/zephyr.py

@@ -74,7 +74,7 @@ def gen_build(self):
 
         vars_node = self.conf.get("vars", None)
         if vars_node:
-            vars_vals = [x.as_str for x in vars_node]
+            vars_vals = [ZephyrBuilder.__escape_vars_vals(x.as_str) for x in vars_node]
             vars_value = " ".join([f"-D{var}" for var in vars_vals])
         else:
             vars_value = ""
@@ -102,6 +102,27 @@ def gen_build(self):
 
         return targets
 
+    @staticmethod
+    def __escape_vars_vals(var: str) -> str:
+        """
+        Escape the given variable value.
+
+        Parameters:
+        - var (str): The variable value to be escaped.
+
+        Returns:
+        - str: The escaped variable value.
+
+        If the variable value starts with "CONFIG_", double quotation mark escaping is added,
+        following the:
+        https://github.com/zephyrproject-rtos/zephyr/pull/49267/commits/d77597783a4c148b70c389c8996112f8b6d1e5ed
+        """
+        if var.startswith("CONFIG_"):
+            vars_vals = utils.escape(utils.escape(var))
+        else:
+            vars_vals = utils.escape(var)
+        return vars_vals
+
     def get_targets(self):
         "Return list of targets that are generated by this build"
         return [os.path.join(self.build_dir, t.as_str) for t in self.conf["target_images"]]