cmake_host_system_information: query windows registry

Fixes: #21240, #23367

1 files changed, 55 insertions, 0 deletions

diff --git a/Source/cmWindowsRegistry.h b/Source/cmWindowsRegistry.h
new file mode 100644
index 0000000..6f10b3a
--- /dev/null
+++ b/Source/cmWindowsRegistry.h
@@ -0,0 +1,55 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include <cm/optional>
+#include <cm/string_view>
+#include <cmext/string_view>
+
+class cmMakefile;
+
+class cmWindowsRegistry
+{
+public:
+  cmWindowsRegistry(cmMakefile&);
+
+  enum class View
+  {
+    Both,
+    Target,
+    Host,
+    Reg64_32,
+    Reg32_64,
+    Reg32,
+    Reg64
+  };
+
+  cm::optional<std::string> ReadValue(cm::string_view key,
+                                      View view = View::Both,
+                                      cm::string_view separator = "\0"_s)
+  {
+    return this->ReadValue(key, ""_s, view, separator);
+  }
+  cm::optional<std::string> ReadValue(cm::string_view key,
+                                      cm::string_view name,
+                                      View view = View::Both,
+                                      cm::string_view separator = "\0"_s);
+
+  cm::optional<std::vector<std::string>> GetValueNames(cm::string_view key,
+                                                       View view = View::Both);
+  cm::optional<std::vector<std::string>> GetSubKeys(cm::string_view key,
+                                                    View view = View::Both);
+
+  cm::string_view GetLastError() const;
+
+private:
+#if defined(_WIN32) && !defined(__CYGWIN__)
+  std::vector<View> ComputeViews(View view);
+
+  int TargetSize = 0;
+#endif
+  std::string LastError;
+};