Common/FileSystem: Add a helper to get root directory list

src/common/file_system.cpp

@@ -4,6 +4,7 @@
 #include "log.h"
 #include "string_util.h"
 #include <algorithm>
+#include <cstdlib>
 #include <cstring>
 
 #ifdef __APPLE__
@@ -313,6 +314,33 @@ std::string_view GetFileTitleFromPath(const char* path)
     return std::string_view(path);
 }
 
+std::vector<std::string> GetRootDirectoryList()
+{
+  std::vector<std::string> results;
+
+#ifdef WIN32
+  char buf[256];
+  if (GetLogicalDriveStringsA(sizeof(buf), buf) != 0)
+  {
+    const char* ptr = buf;
+    while (*ptr != '\0')
+    {
+      const std::size_t len = std::strlen(ptr);
+      results.emplace_back(ptr, len);
+      ptr += len + 1u;
+    }
+  }
+#else
+  const char* home_path = std::getenv("HOME");
+  if (home_path)
+    results.push_back(home_path);
+
+  results.push_back("/");
+#endif
+
+  return results;
+}
+
 void BuildPathRelativeToFile(char* Destination, u32 cbDestination, const char* CurrentFileName, const char* NewFileName,
                              bool OSPath /* = true */, bool Canonicalize /* = true */)
 {

src/common/file_system.h

@@ -154,6 +154,9 @@ std::string_view GetFileNameFromPath(const char* path);
 /// Returns the file title (less the extension and path) from a filename.
 std::string_view GetFileTitleFromPath(const char* path);
 
+/// Returns a list of "root directories" (i.e. root/home directories on Linux, drive letters on Windows).
+std::vector<std::string> GetRootDirectoryList();
+
 // search for files
 bool FindFiles(const char* Path, const char* Pattern, u32 Flags, FindResultsArray* pResults);