WinRcPath: improve performance (#512)

## Description

WinRcPath generally takes about 2 seconds to run, due to calling
multiple .bat files behind the scenes. This change reduces this time to
~0 seconds due to the following changes:

1. It will attempt to load the path from the cache, which is located a
$(WORKSPACE)/Conf/.rc_path. If the loading is a success and the rc_path
still exists, it will use it.

2. If the cache did not exist, or the path provided by the cache does
not exist, it will find the rc path via the .bat files. If that
succeeds, it will write the path to the cache.

- [ ] Impacts functionality?
- **Functionality** - Does the change ultimately impact how firmware
functions?
- Examples: Add a new library, publish a new PPI, update an algorithm,
...
- [ ] Impacts security?
- **Security** - Does the change have a direct security impact on an
application,
    flow, or firmware?
  - Examples: Crypto algorithm change, buffer overflow fix, parameter
    validation improvement, ...
- [ ] Breaking change?
- **Breaking change** - Will anyone consuming this change experience a
break
    in build or boot behavior?
- Examples: Add a new library class, move a module to a different repo,
call
    a function in a new library class in a pre-existing module, ...
- [ ] Includes tests?
  - **Tests** - Does the change include any explicit test code?
  - Examples: Unit tests, integration tests, robot tests, ...
- [ ] Includes documentation?
- **Documentation** - Does the change contain explicit documentation
additions
    outside direct code modifications (and comments)?
- Examples: Update readme file, add feature readme file, link to
documentation
    on an a separate Web page, ...

## How This Was Tested

1. Confirmed the plugin will create a cache file on first run and use it
in later runs
2. Confirmed updating the path in the cache to a wrong value will invoke
the typical means to find the cache and save the correct path into the
cache

## Integration Instructions

N/A

BaseTools/Plugin/WindowsResourceCompiler/WinRcPath.py

@@ -6,27 +6,42 @@
 # Copyright (c) Microsoft Corporation
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 ##
-import os
 import logging
 from edk2toolext.environment.plugintypes.uefi_build_plugin import IUefiBuildPlugin
 import edk2toollib.windows.locate_tools as locate_tools
 from edk2toolext.environment import shell_environment
 from edk2toolext.environment import version_aggregator
+from pathlib import Path
 
+# MU_CHANGE Entire File - Perf improvements
 class WinRcPath(IUefiBuildPlugin):
 
-    def do_post_build(self, thebuilder):
-        return 0
-
     def do_pre_build(self, thebuilder):
         #get the locate tools module
+
+        # Check if the rc.exe path is already cached and still exists
+        cache_path = Path(thebuilder.ws, "Conf", ".rc_path")
+        if cache_path.exists():
+            with open(cache_path, "r") as f:
+                rc_path = Path(f.readline().strip()).absolute()
+                if (rc_path / "rc.exe").exists():
+                    logging.debug(f"Found rc.exe folder in cache: {rc_path}")
+                    self._set_path(rc_path)
+                    return 0
+
+        # If it does not exist, try to find it with FindToolInWinSdk
         path = locate_tools.FindToolInWinSdk("rc.exe")
         if path is None:
             logging.critical("Failed to find rc.exe")
             return 1
-        else:
-            p = os.path.abspath(os.path.dirname(path))
-            shell_environment.GetEnvironment().set_shell_var("WINSDK_PATH_FOR_RC_EXE", p)
-            version_aggregator.GetVersionAggregator().ReportVersion("WINSDK_PATH_FOR_RC_EXE", p, version_aggregator.VersionTypes.INFO)
-            return 0
+
+        path = Path(path).absolute().parent
+        self._set_path(path)
+        cache_path.unlink(missing_ok=True)
+        with cache_path.open("w") as f:
+            f.write(str(path))
         return 0
+
+    def _set_path(self, path: Path):
+        shell_environment.GetEnvironment().set_shell_var("WINSDK_PATH_FOR_RC_EXE", str(path))
+        version_aggregator.GetVersionAggregator().ReportVersion("WINSDK_PATH_FOR_RC_EXE", str(path), version_aggregator.VersionTypes.INFO)