...in with the new.

1 files changed, 134 insertions, 0 deletions

diff --git a/comctl32_windows.c b/comctl32_windows.c
new file mode 100644
index 0000000..841aa80
--- /dev/null
+++ b/comctl32_windows.c
@@ -0,0 +1,134 @@
+// 17 july 2014
+
+#include "winapi_windows.h"
+
+static ULONG_PTR comctlManifestCookie;
+static HMODULE comctl32;
+
+// these are listed as WINAPI in both Microsoft's and MinGW's headers, but not on MSDN for some reason
+BOOL (*WINAPI fv_SetWindowSubclass)(HWND, SUBCLASSPROC, UINT_PTR, DWORD_PTR);
+BOOL (*WINAPI fv_RemoveWindowSubclass)(HWND, SUBCLASSPROC, UINT_PTR);
+LRESULT (*WINAPI fv_DefSubclassProc)(HWND, UINT, WPARAM, LPARAM);
+HIMAGELIST (*WINAPI fv_ImageList_Create)(int, int, UINT, int, int);
+int (*WINAPI fv_ImageList_Add)(HIMAGELIST, HBITMAP, HBITMAP);
+BOOL (*WINAPI fv_ImageList_Destroy)(HIMAGELIST);
+
+#define wantedICCClasses ( \
+	ICC_PROGRESS_CLASS |		/* progress bars */		\
+	ICC_TAB_CLASSES |			/* tabs */				\
+	ICC_LISTVIEW_CLASSES |		/* list views */			\
+	0)
+
+// note that this is an 8-bit character string we're writing; see the encoding clause
+static const char manifest[] = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\" manifestVersion=\"1.0\">\n<assemblyIdentity\n    version=\"1.0.0.0\"\n    processorArchitecture=\"*\"\n    name=\"CompanyName.ProductName.YourApplication\"\n    type=\"win32\"\n/>\n<description>Your application description here.</description>\n<dependency>\n    <dependentAssembly>\n        <assemblyIdentity\n            type=\"win32\"\n            name=\"Microsoft.Windows.Common-Controls\"\n            version=\"6.0.0.0\"\n            processorArchitecture=\"*\"\n            publicKeyToken=\"6595b64144ccf1df\"\n            language=\"*\"\n        />\n    </dependentAssembly>\n</dependency>\n</assembly>\n";
+
+/*
+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
+Because neither Go nor MinGW have ways to compile in resources like this (as far as I know), we have to do the work ourselves.
+*/
+DWORD initCommonControls(char **errmsg)
+{
+	WCHAR temppath[MAX_PATH + 1];
+	WCHAR filename[MAX_PATH + 1];
+	HANDLE file;
+	DWORD nExpected, nGot;
+	ACTCTX actctx;
+	HANDLE ac;
+	INITCOMMONCONTROLSEX icc;
+	FARPROC f;
+	// this is listed as WINAPI in both Microsoft's and MinGW's headers, but not on MSDN for some reason
+	BOOL (*WINAPI ficc)(const LPINITCOMMONCONTROLSEX);
+
+	if (GetTempPathW(MAX_PATH + 1, temppath) == 0) {
+		*errmsg = "error getting temporary path for writing manifest file";
+		return GetLastError();
+	}
+	if (GetTempFileNameW(temppath, L"manifest", 0, filename) == 0) {
+		*errmsg = "error getting temporary filename for writing manifest file";
+		return GetLastError();
+	}
+	file = CreateFileW(filename, GENERIC_WRITE,
+		0,			// don't share while writing
+		NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+	if (file == NULL) {
+		*errmsg = "error creating manifest file";
+		return GetLastError();
+	}
+	nExpected = (sizeof manifest / sizeof manifest[0]) - 1;		// - 1 to omit the terminating null character)
+	SetLastError(0);		// catch errorless short writes
+	if (WriteFile(file, manifest, nExpected, &nGot, NULL) == 0) {
+		*errmsg = "error writing manifest file";
+		return GetLastError();
+	}
+	if (nGot != nExpected) {
+		DWORD lasterr;
+
+		lasterr = GetLastError();
+		*errmsg = "short write to manifest file";
+		if (lasterr == 0)
+			*errmsg = "short write to manifest file without error code";
+		return lasterr;
+	}
+	if (CloseHandle(file) == 0) {
+		*errmsg = "error closing manifest file (this IS an error here because not doing so will prevent Windows from being able to use the manifest file in an activation context)";
+		return GetLastError();
+	}
+
+	ZeroMemory(&actctx, sizeof (ACTCTX));
+	actctx.cbSize = sizeof (ACTCTX);
+	actctx.dwFlags = ACTCTX_FLAG_SET_PROCESS_DEFAULT;
+	actctx.lpSource = filename;
+	ac = CreateActCtx(&actctx);
+	if (ac == INVALID_HANDLE_VALUE) {
+		*errmsg = "error creating activation context for synthesized manifest file";
+		return GetLastError();
+	}
+	if (ActivateActCtx(ac, &comctlManifestCookie) == FALSE) {
+		*errmsg = "error activating activation context for synthesized manifest file";
+		return GetLastError();
+	}
+
+	ZeroMemory(&icc, sizeof (INITCOMMONCONTROLSEX));
+	icc.dwSize = sizeof (INITCOMMONCONTROLSEX);
+	icc.dwICC = wantedICCClasses;
+
+	comctl32 = LoadLibraryW(L"comctl32.dll");
+	if (comctl32 == NULL) {
+		*errmsg = "error loading comctl32.dll";
+		return GetLastError();
+	}
+
+	// GetProcAddress() only takes a multibyte string
+#define LOAD(fn) f = GetProcAddress(comctl32, fn); \
+	if (f == NULL) { \
+		*errmsg = "error loading " fn "()"; \
+		return GetLastError(); \
+	}
+
+	LOAD("InitCommonControlsEx");
+	ficc = (BOOL (*WINAPI)(const LPINITCOMMONCONTROLSEX)) f;
+	LOAD("SetWindowSubclass");
+	fv_SetWindowSubclass = (BOOL (*WINAPI)(HWND, SUBCLASSPROC, UINT_PTR, DWORD_PTR)) f;
+	LOAD("RemoveWindowSubclass");
+	fv_RemoveWindowSubclass = (BOOL (*WINAPI)(HWND, SUBCLASSPROC, UINT_PTR)) f;
+	LOAD("DefSubclassProc");
+	fv_DefSubclassProc = (LRESULT (*WINAPI)(HWND, UINT, WPARAM, LPARAM)) f;
+	LOAD("ImageList_Create");
+	fv_ImageList_Create = (HIMAGELIST (*WINAPI)(int, int, UINT, int, int)) f;
+	LOAD("ImageList_Add");
+	fv_ImageList_Add = (int (*WINAPI)(HIMAGELIST, HBITMAP, HBITMAP)) f;
+	LOAD("ImageList_Destroy");
+	fv_ImageList_Destroy = (BOOL (*WINAPI)(HIMAGELIST)) f;
+
+	if ((*ficc)(&icc) == FALSE) {
+		*errmsg = "error initializing Common Controls (comctl32.dll)";
+		return GetLastError();
+	}
+
+	return 0;
+}