fix: fix out of root static file serving on windows

fix #1982

packages/vite/src/node/server/middlewares/static.ts

@@ -62,18 +62,19 @@ export function serveStaticMiddleware(
 }
 
 export function serveRawFsMiddleware(): Connect.NextHandleFunction {
-  const fsRoot =
-    os.platform() == 'win32' ? process.cwd().split(path.sep)[0] + '/' : '/'
-  const serveFromRoot = sirv(fsRoot, sirvOptions)
+  const isWin = os.platform() === 'win32'
+  const serveFromRoot = sirv('/', sirvOptions)
 
   return (req, res, next) => {
-    const url = req.url!
+    let url = req.url!
     // In some cases (e.g. linked monorepos) files outside of root will
     // reference assets that are also out of served root. In such cases
     // the paths are rewritten to `/@fs/` prefixed paths and must be served by
     // searching based from fs root.
     if (url.startsWith(FS_PREFIX)) {
-      req.url = decodeURI(url.slice(FS_PREFIX.length))
+      url = url.slice(FS_PREFIX.length)
+      if (isWin) url = url.replace(/^[A-Z]:/i, '')
+      req.url = decodeURI(url)
       serveFromRoot(req, res, next)
     } else {
       next()