1 files changed, 132 insertions, 0 deletions
diff --git a/redo/comctl32_windows.go b/redo/comctl32_windows.go
new file mode 100644
index 0000000..6b3d6e5
--- /dev/null
+++ b/redo/comctl32_windows.go
@@ -0,0 +1,132 @@
+// 25 february 2014
+
+package ui
+
+import (
+	"fmt"
+	"io/ioutil"
+	"syscall"
+	"unsafe"
+)
+
+// pretty much every constant here except _WM_USER is from commctrl.h, except where noted
+
+var (
+	comctlManifestCookie t_ULONG_PTR
+)
+
+/*
+Windows requires a manifest file to enable Common Controls version 6.
+The only way to not require an external manifest is to synthesize the manifest ourselves.
+We can use the activation context API to load it at runtime.
+References:
+- http://stackoverflow.com/questions/4308503/how-to-enable-visual-styles-without-a-manifest
+- http://support.microsoft.com/kb/830033
+*/
+func forceCommonControls6() error {
+	manifestfile, err := ioutil.TempFile("", "gouicomctl32v6manifest")
+	if err != nil {
+		return fmt.Errorf("error creating synthesized manifest file: %v", err)
+	}
+	_, err = manifestfile.Write(manifest)
+	if err != nil {
+		return fmt.Errorf("error writing synthesized manifest file: %v", err)
+	}
+	filename := manifestfile.Name()
+	// we now have to close the file, otherwise ActivateActCtx() will complain that it's in use by another program
+	// if ioutil.TempFile() ever changes so that the file is deleted when it is closed, this will need to change
+	manifestfile.Close()
+
+	var actctx s_ACTCTXW
+
+	actctx.cbSize = uint32(unsafe.Sizeof(actctx))
+	// make this context the process default, just to be safe
+	actctx.dwFlags = c_ACTCTX_FLAG_SET_PROCESS_DEFAULT
+	actctx.lpSource = syscall.StringToUTF16Ptr(filename)
+
+	res, err := f_CreateActCtxW(&actctx)
+	if res == c_INVALID_HANDLE_VALUE {
+		return fmt.Errorf("error creating activation context for synthesized manifest file: %v", err)
+	}
+	res, err = f_ActivateActCtx(res, &comctlManifestCookie)
+	if res == c_FALSE {
+		return fmt.Errorf("error activating activation context for synthesized manifest file: %v", err)
+	}
+	return nil
+}
+
+func initCommonControls() (err error) {
+	var icc s_INITCOMMONCONTROLSEX
+
+	err = forceCommonControls6()
+	if err != nil {
+		return fmt.Errorf("error forcing Common Controls version 6 (or newer): %v", err)
+	}
+
+	icc.dwSize = uint32(unsafe.Sizeof(icc))
+	icc.dwICC = c_ICC_PROGRESS_CLASS
+
+	// TODO call LoadLibraryW() directly
+	comctl32 := syscall.NewLazyDLL("comctl32.dll")
+	r1, _, err := comctl32.NewProc("InitCommonControlsEx").Call(uintptr(unsafe.Pointer(&icc)))
+	if r1 == c_FALSE {
+		return fmt.Errorf("error initializing Common Controls (comctl32.dll); Windows last error: %v", err)
+	}
+	fv_SetWindowSubclass = comctl32.NewProc("SetWindowSubclass")
+	fv_RemoveWindowSubclass = comctl32.NewProc("RemoveWindowSubclass")
+	fv_DefSubclassProc = comctl32.NewProc("DefSubclassProc")
+	return nil
+}
+
+// Common Controls class names.
+const (
+	// x (lowercase) prefix to avoid being caught by the constants generator
+	x_PROGRESS_CLASS = "msctls_progress32"
+)
+
+// this isn't generated by the constants generator because we need to load it from the correct version of comctl32.dll
+
+var (
+	fv_SetWindowSubclass *syscall.LazyProc
+	fv_RemoveWindowSubclass *syscall.LazyProc
+	fv_DefSubclassProc *syscall.LazyProc
+)
+
+func f_SetWindowSubclass(hwnd uintptr, subproc uintptr, id t_UINT_PTR, data t_DWORD_PTR) (uintptr, error) {
+	r1, _, err := fv_SetWindowSubclass.Call(hwnd, subproc, uintptr(id), uintptr(data))
+	return r1, err
+}
+
+func f_RemoveWindowSubclass(hwnd uintptr, subproc uintptr, id t_UINT_PTR) (uintptr, error) {
+	r1, _, err := fv_RemoveWindowSubclass.Call(hwnd, subproc, uintptr(id))
+	return r1, err
+}
+
+func f_DefSubclassProc(hwnd uintptr, uMsg t_UINT, wParam t_WPARAM, lParam t_LPARAM, id t_UINT_PTR, data t_DWORD_PTR) t_LRESULT {
+	r1, _, _ := fv_DefSubclassProc.Call(hwnd, uintptr(uMsg), uintptr(wParam), uintptr(lParam), uintptr(id), uintptr(data))
+	return t_LRESULT(r1)
+}
+
+var manifest = []byte(`<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+<assemblyIdentity
+    version="1.0.0.0"
+    processorArchitecture="*"
+    name="CompanyName.ProductName.YourApplication"
+    type="win32"
+/>
+<description>Your application description here.</description>
+<dependency>
+    <dependentAssembly>
+        <assemblyIdentity
+            type="win32"
+            name="Microsoft.Windows.Common-Controls"
+            version="6.0.0.0"
+            processorArchitecture="*"
+            publicKeyToken="6595b64144ccf1df"
+            language="*"
+        />
+    </dependentAssembly>
+</dependency>
+</assembly>
+`)