1 files changed, 90 insertions, 0 deletions
diff --git a/cli/util/windows.rs b/cli/util/windows.rs
new file mode 100644
index 000000000..0801ff2f5
--- /dev/null
+++ b/cli/util/windows.rs
@@ -0,0 +1,90 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+/// Ensures that stdin, stdout, and stderr are open and have valid HANDLEs
+/// associated with them. There are many places where a `std::fs::File` is
+/// constructed from a stdio handle; if the handle is null this causes a panic.
+pub fn ensure_stdio_open() {
+  #[cfg(windows)]
+  // SAFETY: winapi calls
+  unsafe {
+    use std::mem::size_of;
+    use winapi::shared::minwindef::DWORD;
+    use winapi::shared::minwindef::FALSE;
+    use winapi::shared::minwindef::TRUE;
+    use winapi::shared::ntdef::NULL;
+    use winapi::shared::winerror::ERROR_INVALID_HANDLE;
+    use winapi::um::errhandlingapi::GetLastError;
+    use winapi::um::fileapi::CreateFileA;
+    use winapi::um::fileapi::OPEN_EXISTING;
+    use winapi::um::handleapi::GetHandleInformation;
+    use winapi::um::handleapi::INVALID_HANDLE_VALUE;
+    use winapi::um::minwinbase::SECURITY_ATTRIBUTES;
+    use winapi::um::processenv::GetStdHandle;
+    use winapi::um::processenv::SetStdHandle;
+    use winapi::um::winbase::STD_ERROR_HANDLE;
+    use winapi::um::winbase::STD_INPUT_HANDLE;
+    use winapi::um::winbase::STD_OUTPUT_HANDLE;
+    use winapi::um::winnt::FILE_ATTRIBUTE_NORMAL;
+    use winapi::um::winnt::FILE_GENERIC_READ;
+    use winapi::um::winnt::FILE_GENERIC_WRITE;
+    use winapi::um::winnt::FILE_READ_ATTRIBUTES;
+    use winapi::um::winnt::FILE_SHARE_READ;
+    use winapi::um::winnt::FILE_SHARE_WRITE;
+
+    for std_handle in [STD_INPUT_HANDLE, STD_OUTPUT_HANDLE, STD_ERROR_HANDLE] {
+      // Check whether stdio handle is open.
+      let is_valid = match GetStdHandle(std_handle) {
+        NULL | INVALID_HANDLE_VALUE => false,
+        handle => {
+          // The stdio handle is open; check whether its handle is valid.
+          let mut flags: DWORD = 0;
+          match GetHandleInformation(handle, &mut flags) {
+            TRUE => true,
+            FALSE if GetLastError() == ERROR_INVALID_HANDLE => false,
+            FALSE => {
+              panic!("GetHandleInformation failed (error {})", GetLastError());
+            }
+            _ => unreachable!(),
+          }
+        }
+      };
+
+      if !is_valid {
+        // Open NUL device.
+        let desired_access = match std_handle {
+          STD_INPUT_HANDLE => FILE_GENERIC_READ,
+          _ => FILE_GENERIC_WRITE | FILE_READ_ATTRIBUTES,
+        };
+        let security_attributes = SECURITY_ATTRIBUTES {
+          nLength: size_of::<SECURITY_ATTRIBUTES>() as DWORD,
+          lpSecurityDescriptor: NULL,
+          bInheritHandle: TRUE,
+        };
+        let file_handle = CreateFileA(
+          b"\\\\?\\NUL\0" as *const _ as *mut _,
+          desired_access,
+          FILE_SHARE_READ | FILE_SHARE_WRITE,
+          &security_attributes as *const _ as *mut _,
+          OPEN_EXISTING,
+          FILE_ATTRIBUTE_NORMAL,
+          NULL,
+        );
+        match file_handle {
+          NULL => unreachable!(),
+          INVALID_HANDLE_VALUE => {
+            panic!("Could not open NUL device (error {})", GetLastError());
+          }
+          _ => {}
+        }
+
+        // Assign the opened NUL handle to the missing stdio handle.
+        let success = SetStdHandle(std_handle, file_handle);
+        match success {
+          TRUE => {}
+          FALSE => panic!("SetStdHandle failed (error {})", GetLastError()),
+          _ => unreachable!(),
+        }
+      }
+    }
+  }
+}