Make Geany agnostic to Win32 API text encoding

win32-unicode.patch

diff --git a/src/win32.c b/src/win32.c
index 34b7d93..f5ffc9a 100644
--- a/src/win32.c
+++ b/src/win32.c
@@ -32,6 +32,10 @@
 /* Needed for SHGFP_TYPE */
 #define _WIN32_IE 0x0500
 
+#ifndef UNICODE
+# define UNICODE
+#endif
+
 #include "win32.h"
 
 #ifdef G_OS_WIN32
@@ -67,6 +71,71 @@
 static UINT_PTR dialog_timer = 0;
 
 
+// converts a UTF8 string into a TCHAR (wchar_t when UNICODE is defined)
+static TCHAR *win32_utf8_to_tchar_len(const gchar *utf8_string, gssize len)
+{
+	TCHAR *out_str = NULL;
+#ifdef UNICODE
+	// utf8 to wide
+	int size = MultiByteToWideChar(CP_UTF8, 0, utf8_string, len, NULL, 0);
+	if (size == 0)
+		return NULL;
+	out_str = g_malloc(size * sizeof(TCHAR));
+	if (out_str == NULL)
+		return NULL;
+	MultiByteToWideChar(CP_UTF8, 0, utf8_string, len, out_str, size);
+#else
+	// utf8 to ascii
+	if (len < 0)
+		len = strlen(utf8_string);
+	out_str = g_strndup(utf8_string, len);
+	for (gsize i = 0; i < len; i++)
+	{
+		if (out_str[i] > 127)
+			out_str[i] = '?';
+	}
+#endif
+	return out_str;
+}
+
+
+static inline TCHAR *win32_utf8_to_tchar(const gchar *utf8_string)
+{
+	return win32_utf8_to_tchar_len(utf8_string, -1);
+}
+
+
+// converts a TCHAR string (wchar_t when UNICODE is defined) to a UTF8 string
+static gchar *win32_tchar_to_utf8_len(const TCHAR *tchar_string, gssize len)
+{
+	gchar *out_str = NULL;
+#ifdef UNICODE
+		// wide to utf8
+		int size = WideCharToMultiByte(CP_UTF8, 0, tchar_string, len,
+			NULL, 0, NULL, NULL);
+		if (size == 0)
+			return NULL;
+		out_str = g_malloc(size);
+		if (out_str == NULL)
+			return NULL;
+		WideCharToMultiByte(CP_UTF8, 0, tchar_string, len, out_str, size,
+			NULL, NULL);
+#else
+		// ascii to utf8
+		if (len < 0)
+			len = strlen(tchar_string);
+		out_str = g_strndup(tchar_string, len);
+#endif
+	return out_str;
+}
+
+
+static inline gchar *win32_tchar_to_utf8(const TCHAR *tchar_string)
+{
+	return win32_tchar_to_utf8_len(tchar_string, -1);
+}
+
+
 G_INLINE_FUNC void win32_dialog_reset_timer(HWND hwnd)
 {
 	if (G_UNLIKELY(dialog_timer != 0))
@@ -132,11 +201,11 @@ UINT_PTR CALLBACK win32_dialog_hook_proc(HWND dlg, UINT msg, WPARAM wParam, LPAR
 }
 
 
-static wchar_t *get_file_filters(void)
+static TCHAR *get_file_filters(void)
 {
 	gchar *string;
 	guint i, j, len;
-	static wchar_t title[4096];
+	TCHAR *title;
 	GString *str = g_string_sized_new(100);
 	GString *all_patterns = g_string_sized_new(100);
 	GSList *node;
@@ -175,16 +244,17 @@ static wchar_t *get_file_filters(void)
 	g_strdelimit(string, "\t", '\0');
 	g_assert(string[len - 1] == 0x0);
 	MultiByteToWideChar(CP_UTF8, 0, string, len, title, G_N_ELEMENTS(title));
+	title = win32_utf8_to_tchar_len(string, len);
 	g_free(string);
 
 	return title;
 }
 
 
-static wchar_t *get_file_filter_all_files(void)
+static TCHAR *get_file_filter_all_files(void)
 {
 	guint len;
-	static wchar_t title[4096];
+	TCHAR *title;
 	gchar *filter;
 
 	/* create meta file filter "All files" */
@@ -193,18 +263,18 @@ static wchar_t *get_file_filter_all_files(void)
 	len = strlen(filter);
 	g_strdelimit(filter, "\t", '\0');
 	g_assert(filter[len - 1] == 0x0);
-	MultiByteToWideChar(CP_UTF8, 0, filter, len, title, G_N_ELEMENTS(title));
+	title = win32_utf8_to_tchar_len(filter, len);
 	g_free(filter);
 
 	return title;
 }
 
 
-static wchar_t *get_filters(gboolean project_files)
+static TCHAR *get_filters(gboolean project_files)
 {
 	gchar *string;
 	gint len;
-	static wchar_t title[1024];
+	TCHAR *title;
 
 	if (project_files)
 	{
@@ -221,7 +291,7 @@ static wchar_t *get_filters(gboolean project_files)
 	len = strlen(string);
 	g_strdelimit(string, "\t", '\0');
 	g_assert(string[len - 1] == 0x0);
-	MultiByteToWideChar(CP_UTF8, 0, string, len, title, G_N_ELEMENTS(title));
+	title = win32_utf8_to_tchar_len(string, len);
 	g_free(string);
 
 	return title;
@@ -230,20 +300,18 @@ static wchar_t *get_filters(gboolean project_files)
 
 /* Converts the given UTF-8 filename or directory name into something usable for Windows and
  * returns the directory part of the given filename. */
-static wchar_t *get_dir_for_path(const gchar *utf8_filename)
+static TCHAR *get_dir_for_path(const gchar *utf8_filename)
 {
-	static wchar_t w_dir[MAX_PATH];
+	TCHAR *w_dir;
 	gchar *result;
 
 	if (g_file_test(utf8_filename, G_FILE_TEST_IS_DIR))
-		result = (gchar*) utf8_filename;
+		result = g_strdup(utf8_filename);
 	else
 		result = g_path_get_dirname(utf8_filename);
 
-	MultiByteToWideChar(CP_UTF8, 0, result, -1, w_dir, G_N_ELEMENTS(w_dir));
-
-	if (result != utf8_filename)
-		g_free(result);
+	w_dir = win32_utf8_to_tchar(result);
+	g_free(result);
 
 	return w_dir;
 }
@@ -260,16 +328,16 @@ INT CALLBACK BrowseCallbackProc(HWND hwnd, UINT uMsg, LPARAM lp, LPARAM pData)
 	{
 		case BFFM_INITIALIZED:
 		{
-			SendMessageW(hwnd, BFFM_SETSELECTIONW, TRUE, pData);
+			SendMessage(hwnd, BFFM_SETSELECTIONW, TRUE, pData);
 			break;
 		}
 		case BFFM_SELCHANGED:
 		{
 			/* set the status window to the currently selected path. */
-			static wchar_t szDir[MAX_PATH];
-			if (SHGetPathFromIDListW((LPITEMIDLIST) lp, szDir))
+			TCHAR szDir[MAX_PATH];
+			if (SHGetPathFromIDList((LPITEMIDLIST) lp, szDir))
 			{
-				SendMessageW(hwnd, BFFM_SETSTATUSTEXTW, 0, (LPARAM) szDir);
+				SendMessage(hwnd, BFFM_SETSTATUSTEXTW, 0, (LPARAM) szDir);
 			}
 			break;
 		}
@@ -286,10 +354,10 @@ gchar *win32_show_folder_dialog(GtkWidget *parent, const gchar *title, const gch
 	BROWSEINFOW bi;
 	LPCITEMIDLIST pidl;
 	gchar *result = NULL;
-	wchar_t fname[MAX_PATH];
-	wchar_t w_title[512];
+	TCHAR fname[MAX_PATH];
+	TCHAR *w_title;
 
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_title = win32_utf8_to_tchar(title);
 
 	if (parent == NULL)
 		parent = main_widgets.window;
@@ -302,16 +370,16 @@ gchar *win32_show_folder_dialog(GtkWidget *parent, const gchar *title, const gch
 	bi.lParam = (LPARAM) get_dir_for_path(initial_dir);
 	bi.ulFlags = BIF_DONTGOBELOWDOMAIN | BIF_RETURNONLYFSDIRS | BIF_STATUSTEXT | BIF_USENEWUI;
 
-	pidl = SHBrowseForFolderW(&bi);
+	pidl = SHBrowseForFolder(&bi);
+
+	g_free(w_title);
+	g_free((gchar*) bi.lParam);
 
 	/* convert the strange Windows folder list item something into an usual path string ;-) */
 	if (pidl != 0)
 	{
-		if (SHGetPathFromIDListW(pidl, fname))
-		{
-			result = g_malloc0(MAX_PATH * 2);
-			WideCharToMultiByte(CP_UTF8, 0, fname, -1, result, MAX_PATH * 2, NULL, NULL);
-		}
+		if (SHGetPathFromIDList(pidl, fname))
+			result = win32_tchar_to_utf8(fname);
 		/* SHBrowseForFolder() probably leaks memory here, but how to free the allocated memory? */
 	}
 	return result;
@@ -330,13 +398,17 @@ gchar *win32_show_project_open_dialog(GtkWidget *parent, const gchar *title,
 {
 	OPENFILENAMEW of;
 	gint retval;
-	wchar_t fname[MAX_PATH];
-	wchar_t w_title[512];
+	TCHAR fname[MAX_PATH];
+	TCHAR *w_title;
+	TCHAR *w_filter;
+	TCHAR *w_dir;
 	gchar *filename;
 
 	fname[0] = '\0';
 
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_title = win32_utf8_to_tchar(title);
+	w_filter = get_filters(project_file_filter);
+	w_dir = get_dir_for_path(initial_dir);
 
 	if (parent == NULL)
 		parent = main_widgets.window;
@@ -345,23 +417,26 @@ gchar *win32_show_project_open_dialog(GtkWidget *parent, const gchar *title,
 	memset(&of, 0, sizeof of);
 	of.lStructSize = sizeof of;
 	of.hwndOwner = GDK_WINDOW_HWND(gtk_widget_get_window(parent));
-	of.lpstrFilter = get_filters(project_file_filter);
+	of.lpstrFilter = w_filter;
 
 	of.lpstrCustomFilter = NULL;
 	of.nFilterIndex = 0;
 	of.lpstrFile = fname;
-	of.lpstrInitialDir = get_dir_for_path(initial_dir);
+	of.lpstrInitialDir = w_dir;
 	of.nMaxFile = 2048;
 	of.lpstrFileTitle = NULL;
 	of.lpstrTitle = w_title;
-	of.lpstrDefExt = L"";
+	of.lpstrDefExt = TEXT("");
 	of.Flags = OFN_PATHMUSTEXIST | OFN_EXPLORER | OFN_HIDEREADONLY |
 		OFN_ENABLEHOOK | OFN_ENABLESIZING;
 	of.lpfnHook = win32_dialog_explorer_hook_proc;
 	if (! allow_new_file)
 		of.Flags |= OFN_FILEMUSTEXIST;
 
-	retval = GetOpenFileNameW(&of);
+	retval = GetOpenFileName(&of);
+	g_free(w_title);
+	g_free(w_filter);
+	g_free(w_dir);
 
 	if (! retval)
 	{
@@ -374,9 +449,8 @@ gchar *win32_show_project_open_dialog(GtkWidget *parent, const gchar *title,
 		}
 		return NULL;
 	}
-	/* convert the resulting filename into UTF-8 (from whatever encoding it has at this moment) */
-	filename = g_malloc0(MAX_PATH * 2);
-	WideCharToMultiByte(CP_UTF8, 0, fname, -1, filename, MAX_PATH * 2, NULL, NULL);
+
+	filename = win32_tchar_to_utf8(fname);
 
 	return filename;
 }
@@ -389,23 +463,26 @@ gboolean win32_show_document_open_dialog(GtkWindow *parent, const gchar *title,
 	OPENFILENAMEW of;
 	gint retval;
 	guint x;
-	gchar tmp[MAX_PATH];
-	wchar_t fname[MAX_PATH];
-	wchar_t w_dir[MAX_PATH];
-	wchar_t w_title[512];
+	TCHAR fname[MAX_PATH];
+	TCHAR *w_dir;
+	TCHAR *w_title;
+	TCHAR *w_filter;
 
 	fname[0] = '\0';
 
 	if (initial_dir != NULL)
-		MultiByteToWideChar(CP_UTF8, 0, initial_dir, -1, w_dir, G_N_ELEMENTS(w_dir));
+		w_dir = win32_utf8_to_tchar(initial_dir);
+	else
+		w_dir = g_malloc0(sizeof(TCHAR));
 
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_title = win32_utf8_to_tchar(title);
+	w_filter = get_file_filters();
 
 	/* initialise file dialog info struct */
 	memset(&of, 0, sizeof of);
 	of.lStructSize = sizeof of;
 	of.hwndOwner = GDK_WINDOW_HWND(gtk_widget_get_window(GTK_WIDGET(parent)));
-	of.lpstrFilter = get_file_filters();
+	of.lpstrFilter = w_filter;
 
 	of.lpstrCustomFilter = NULL;
 	of.nFilterIndex = GEANY_FILETYPES_NONE + 1;
@@ -414,12 +491,15 @@ gboolean win32_show_document_open_dialog(GtkWindow *parent, const gchar *title,
 	of.nMaxFile = 2048;
 	of.lpstrFileTitle = NULL;
 	of.lpstrTitle = w_title;
-	of.lpstrDefExt = L"";
+	of.lpstrDefExt = TEXT("");
 	of.Flags = OFN_ALLOWMULTISELECT | OFN_FILEMUSTEXIST | OFN_EXPLORER |
 		OFN_ENABLEHOOK | OFN_ENABLESIZING;
 	of.lpfnHook = win32_dialog_explorer_hook_proc;
 
-	retval = GetOpenFileNameW(&of);
+	retval = GetOpenFileName(&of);
+	g_free(w_dir);
+	g_free(w_title);
+	g_free(w_filter);
 
 	if (!retval)
 	{
@@ -429,22 +509,23 @@ gboolean win32_show_document_open_dialog(GtkWindow *parent, const gchar *title,
 			g_snprintf(error, sizeof error, "File dialog box error (%x)", (int)CommDlgExtendedError());
 			win32_message_dialog(NULL, GTK_MESSAGE_ERROR, error);
 		}
+		g_free(w_dir);
+		g_free(w_title);
 		return FALSE;
 	}
 
 	x = of.nFileOffset - 1;
 	if (x != wcslen(fname))
 	{	/* open a single file */
-		WideCharToMultiByte(CP_UTF8, 0, fname, -1, tmp, sizeof(tmp), NULL, NULL);
+		gchar *tmp = win32_tchar_to_utf8(fname);
 		document_open_file(tmp, of.Flags & OFN_READONLY, NULL, NULL);
+		g_free(tmp);
 	}
 	else
 	{	/* open multiple files */
 		gchar file_name[MAX_PATH];
-		gchar dir_name[MAX_PATH];
+		gchar *dir_name = win32_tchar_to_utf8(fname);
 
-		WideCharToMultiByte(CP_UTF8, 0, fname, of.nFileOffset,
-			dir_name, sizeof(dir_name), NULL, NULL);
 		for (; ;)
 		{
 			if (! fname[x])
@@ -452,15 +533,17 @@ gboolean win32_show_document_open_dialog(GtkWindow *parent, const gchar *title,
 				if (! fname[x + 1])
 					break;
 
-				WideCharToMultiByte(CP_UTF8, 0, fname + x + 1, -1,
-					tmp, sizeof(tmp), NULL, NULL);
+				gchar *tmp = win32_tchar_to_utf8(fname + x + 1);
 				g_snprintf(file_name, 511, "%s\\%s", dir_name, tmp);
+				g_free(tmp);
 
 				/* convert the resulting filename into UTF-8 */
 				document_open_file(file_name, of.Flags & OFN_READONLY, NULL, NULL);
 			}
 			x++;
 		}
+
+		g_free(dir_name);
 	}
 	return (retval != 0);
 }
@@ -471,33 +554,30 @@ gchar *win32_show_document_save_as_dialog(GtkWindow *parent, const gchar *title,
 {
 	OPENFILENAMEW of;
 	gint retval;
-	gchar tmp[MAX_PATH];
-	wchar_t w_file[MAX_PATH];
-	wchar_t w_title[512];
+	TCHAR *w_file;
+	TCHAR *w_title;
+	TCHAR *w_filter;
 	int n;
 
-	w_file[0] = '\0';
-
-	/* Convert the name of the file for of.lpstrFile */
-	n = MultiByteToWideChar(CP_UTF8, 0, DOC_FILENAME(doc), -1, w_file, G_N_ELEMENTS(w_file));
-
 	/* If creating a new file name, convert and append the extension if any */
-	if (! doc->file_name && doc->file_type && doc->file_type->extension &&
-		n + 1 < (int)G_N_ELEMENTS(w_file))
+	if (! doc->file_name && doc->file_type && doc->file_type->extension)
 	{
-		w_file[n - 1] = L'.';
-		MultiByteToWideChar(CP_UTF8, 0, doc->file_type->extension, -1, &w_file[n],
-				G_N_ELEMENTS(w_file) - n - 1);
+		gchar *file = g_strdup_printf("%s.%s", DOC_FILENAME(doc), doc->file_type->extension);
+		w_file = win32_utf8_to_tchar(file);
+		g_free(file);
 	}
+	else
+		w_file = win32_utf8_to_tchar(DOC_FILENAME(doc));
 
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_title = win32_utf8_to_tchar(title);
+	w_filter = get_file_filter_all_files();
 
 	/* initialise file dialog info struct */
 	memset(&of, 0, sizeof of);
 	of.lStructSize = sizeof of;
 	of.hwndOwner = GDK_WINDOW_HWND(gtk_widget_get_window(GTK_WIDGET(parent)));
 
-	of.lpstrFilter = get_file_filter_all_files();
+	of.lpstrFilter = w_filter;
 	of.lpstrCustomFilter = NULL;
 	of.nFilterIndex = 0;
 
@@ -505,10 +585,13 @@ gchar *win32_show_document_save_as_dialog(GtkWindow *parent, const gchar *title,
 	of.nMaxFile = 2048;
 	of.lpstrFileTitle = NULL;
 	of.lpstrTitle = w_title;
-	of.lpstrDefExt = L"";
+	of.lpstrDefExt = TEXT("");
 	of.Flags = OFN_OVERWRITEPROMPT | OFN_EXPLORER | OFN_ENABLEHOOK | OFN_ENABLESIZING;
 	of.lpfnHook = win32_dialog_explorer_hook_proc;
-	retval = GetSaveFileNameW(&of);
+	retval = GetSaveFileName(&of);
+
+	g_free(w_title);
+	g_free(w_filter);
 
 	if (! retval)
 	{
@@ -519,12 +602,13 @@ gchar *win32_show_document_save_as_dialog(GtkWindow *parent, const gchar *title,
 			win32_message_dialog(NULL, GTK_MESSAGE_ERROR, error);
 			g_free(error);
 		}
+		g_free(w_file);
 		return NULL;
 	}
 
-	WideCharToMultiByte(CP_UTF8, 0, w_file, -1, tmp, sizeof(tmp), NULL, NULL);
-
-	return g_strdup(tmp);
+	gchar *result = win32_tchar_to_utf8(w_file);
+	g_free(w_file);
+	return result;
 }
 
 
@@ -534,16 +618,15 @@ gchar *win32_show_file_dialog(GtkWindow *parent, const gchar *title, const gchar
 {
 	OPENFILENAMEW of;
 	gint retval;
-	gchar tmp[MAX_PATH];
-	wchar_t w_file[MAX_PATH];
-	wchar_t w_title[512];
-
-	w_file[0] = '\0';
+	TCHAR *w_file;
+	TCHAR *w_title;
 
 	if (initial_file != NULL)
-		MultiByteToWideChar(CP_UTF8, 0, initial_file, -1, w_file, G_N_ELEMENTS(w_file));
+		w_file = win32_utf8_to_tchar(initial_file);
+	else
+		w_file = g_malloc0(sizeof(TCHAR));
 
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_title = win32_utf8_to_tchar(title);
 
 	/* initialise file dialog info struct */
 	memset(&of, 0, sizeof of);
@@ -554,10 +637,12 @@ gchar *win32_show_file_dialog(GtkWindow *parent, const gchar *title, const gchar
 	of.nMaxFile = 2048;
 	of.lpstrFileTitle = NULL;
 	of.lpstrTitle = w_title;
-	of.lpstrDefExt = L"";
+	of.lpstrDefExt = TEXT("");
 	of.Flags = OFN_FILEMUSTEXIST | OFN_EXPLORER | OFN_ENABLEHOOK | OFN_ENABLESIZING;
 	of.lpfnHook = win32_dialog_explorer_hook_proc;
-	retval = GetOpenFileNameW(&of);
+	retval = GetOpenFileName(&of);
+
+	g_free(w_title);
 
 	if (! retval)
 	{
@@ -568,12 +653,13 @@ gchar *win32_show_file_dialog(GtkWindow *parent, const gchar *title, const gchar
 			win32_message_dialog(NULL, GTK_MESSAGE_ERROR, error);
 			g_free(error);
 		}
+		g_free(w_file);
 		return NULL;
 	}
 
-	WideCharToMultiByte(CP_UTF8, 0, w_file, -1, tmp, sizeof(tmp), NULL, NULL);
-
-	return g_strdup(tmp);
+	gchar *result = win32_tchar_to_utf8(w_file);
+	g_free(w_file);
+	return result;
 }
 
 
@@ -640,30 +726,32 @@ void win32_show_pref_file_dialog(GtkEntry *item)
 {
 	OPENFILENAMEW of;
 	gint retval, len;
-	wchar_t fname[MAX_PATH];
+	TCHAR *fname;
+	TCHAR *w_filter;
 	gchar tmp[MAX_PATH];
-	gchar **field, *filename;
+	gchar **field;
 
-	fname[0] = '\0';
+	w_filter = get_filters(FALSE);
 
 	/* cut the options from the command line */
 	field = g_strsplit(gtk_entry_get_text(GTK_ENTRY(item)), " ", 2);
 	if (field[0])
 	{
-		filename = g_find_program_in_path(field[0]);
+		gchar *filename = g_find_program_in_path(field[0]);
 		if (filename != NULL && g_file_test(filename, G_FILE_TEST_EXISTS))
-		{
-			MultiByteToWideChar(CP_UTF8, 0, filename, -1, fname, G_N_ELEMENTS(fname));
-			g_free(filename);
-		}
+			fname = win32_utf8_to_tchar(filename);
+		g_free(filename);
 	}
 
+	if (fname == NULL)
+		fname = g_malloc0(sizeof(TCHAR));
+
 	/* initialize file dialog info struct */
 	memset(&of, 0, sizeof of);
 	of.lStructSize = sizeof of;
 	of.hwndOwner = GDK_WINDOW_HWND(gtk_widget_get_window(ui_widgets.prefs_dialog));
 
-	of.lpstrFilter = get_filters(FALSE);
+	of.lpstrFilter = w_filter;
 	of.lpstrCustomFilter = NULL;
 	of.nFilterIndex = 1;
 
@@ -673,11 +761,13 @@ void win32_show_pref_file_dialog(GtkEntry *item)
 	/*of.lpstrInitialDir = g_get_home_dir();*/
 	of.lpstrInitialDir = NULL;
 	of.lpstrTitle = NULL;
-	of.lpstrDefExt = L"exe";
+	of.lpstrDefExt = TEXT("exe");
 	of.Flags = OFN_HIDEREADONLY | OFN_FILEMUSTEXIST | OFN_EXPLORER |
 		OFN_ENABLEHOOK | OFN_ENABLESIZING;
 	of.lpfnHook = win32_dialog_explorer_hook_proc;
-	retval = GetOpenFileNameW(&of);
+	retval = GetOpenFileName(&of);
+
+	g_free(w_filter);
 
 	if (!retval)
 	{
@@ -688,16 +778,21 @@ void win32_show_pref_file_dialog(GtkEntry *item)
 			win32_message_dialog(NULL, GTK_MESSAGE_ERROR, error);
 		}
 		g_strfreev(field);
+		g_free(fname);
 		return;
 	}
 
+	// FIXME: use win32_tchar_to_utf8() here
 	len = WideCharToMultiByte(CP_UTF8, 0, fname, -1, tmp, sizeof(tmp), NULL, NULL);
 	if ((of.nFileOffset - 1) != len)
 	{
+		gchar *filename;
 		if (g_strv_length(field) > 1)
+		{
 			/* add the command line args of the old command */
 			/** TODO this fails badly when the old command contained spaces, we need quoting here */
 			filename = g_strconcat(tmp, " ", field[1], NULL);
+		}
 		else
 		{
 			filename = g_strdup(tmp);
@@ -706,6 +801,7 @@ void win32_show_pref_file_dialog(GtkEntry *item)
 		g_free(filename);
 	}
 	g_strfreev(field);
+	g_free(fname);
 }
 
 
@@ -719,8 +815,8 @@ gboolean win32_message_dialog(GtkWidget *parent, GtkMessageType type, const gcha
 	guint t;
 	const gchar *title;
 	HWND parent_hwnd = NULL;
-	static wchar_t w_msg[512];
-	static wchar_t w_title[512];
+	TCHAR *w_msg;
+	TCHAR *w_title;
 
 	switch (type)
 	{
@@ -751,9 +847,8 @@ gboolean win32_message_dialog(GtkWidget *parent, GtkMessageType type, const gcha
 	}
 
 	/* convert the Unicode chars to wide chars */
-	/** TODO test if LANG == C then possibly skip conversion => g_win32_getlocale() */
-	MultiByteToWideChar(CP_UTF8, 0, msg, -1, w_msg, G_N_ELEMENTS(w_msg));
-	MultiByteToWideChar(CP_UTF8, 0, title, -1, w_title, G_N_ELEMENTS(w_title));
+	w_msg = win32_utf8_to_tchar(msg);
+	w_title = win32_utf8_to_tchar(title);
 
 	if (parent != NULL)
 		parent_hwnd = GDK_WINDOW_HWND(gtk_widget_get_window(parent));
@@ -761,7 +856,9 @@ gboolean win32_message_dialog(GtkWidget *parent, GtkMessageType type, const gcha
 		parent_hwnd = GDK_WINDOW_HWND(gtk_widget_get_window(main_widgets.window));
 
 	/* display the message box */
-	rc = MessageBoxW(parent_hwnd, w_msg, w_title, t);
+	rc = MessageBox(parent_hwnd, w_msg, w_title, t);
+	g_free(w_msg);
+	g_free(w_title);
 
 	if (type == GTK_MESSAGE_QUESTION && rc != IDYES)
 		ret = FALSE;
@@ -773,7 +870,7 @@ gboolean win32_message_dialog(GtkWidget *parent, GtkMessageType type, const gcha
 /* Little wrapper for _waccess(), returns errno or 0 if there was no error */
 gint win32_check_write_permission(const gchar *dir)
 {
-	static wchar_t w_dir[MAX_PATH];
+	TCHAR w_dir[MAX_PATH];
 	MultiByteToWideChar(CP_UTF8, 0, dir, -1, w_dir, G_N_ELEMENTS(w_dir));
 	if (_waccess(w_dir, R_OK | W_OK) != 0)
 		return errno;
@@ -794,7 +891,9 @@ void win32_open_browser(const gchar *uri)
 				uri++;
 		}
 	}
-	ShellExecute(NULL, "open", uri, NULL, NULL, SW_SHOWNORMAL);
+	TCHAR *w_uri = win32_utf8_to_tchar(uri);
+	ShellExecute(NULL, TEXT("open"), w_uri, NULL, NULL, SW_SHOWNORMAL);
+	g_free(w_uri);
 }
 
 
@@ -895,7 +994,7 @@ gchar *win32_expand_environment_variables(const gchar *str)
 
 
 /* From GDK (they got it from MS Knowledge Base article Q130698) */
-static gboolean resolve_link(HWND hWnd, wchar_t *link, gchar **lpszPath)
+static gboolean resolve_link(HWND hWnd, TCHAR *link, gchar **lpszPath)
 {
 	WIN32_FILE_ATTRIBUTE_DATA wfad;
 	HRESULT hres;
@@ -906,7 +1005,7 @@ static gboolean resolve_link(HWND hWnd, wchar_t *link, gchar **lpszPath)
 
 	/* Check if the file is empty first because IShellLink::Resolve for some reason succeeds
 	 * with an empty file and returns an empty "link target". (#524151) */
-	if (!GetFileAttributesExW(link, GetFileExInfoStandard, &wfad) ||
+	if (!GetFileAttributesEx(link, GetFileExInfoStandard, &wfad) ||
 		(wfad.nFileSizeHigh == 0 && wfad.nFileSizeLow == 0))
 	{
 	  return FALSE;
@@ -943,11 +1042,11 @@ static gboolean resolve_link(HWND hWnd, wchar_t *link, gchar **lpszPath)
 
 	if (SUCCEEDED(hres))
 	{
-		wchar_t wtarget[MAX_PATH];
+		TCHAR wtarget[MAX_PATH];
 
 		hres = pslW->lpVtbl->GetPath(pslW, wtarget, MAX_PATH, NULL, 0);
 		if (SUCCEEDED(hres))
-			*lpszPath = g_utf16_to_utf8(wtarget, -1, NULL, NULL, NULL);
+			*lpszPath = win32_tchar_to_utf8(wtarget);
 	}
 
 	if (ppf)
@@ -966,7 +1065,7 @@ static gboolean resolve_link(HWND hWnd, wchar_t *link, gchar **lpszPath)
 gchar *win32_get_shortcut_target(const gchar *file_name)
 {
 	gchar *path = NULL;
-	wchar_t *wfilename = g_utf8_to_utf16(file_name, -1, NULL, NULL, NULL);
+	TCHAR *wfilename = win32_utf8_to_tchar(file_name);
 	HWND hWnd = NULL;
 
 	if (main_widgets.window != NULL)
@@ -988,7 +1087,10 @@ gchar *win32_get_shortcut_target(const gchar *file_name)
 
 void win32_set_working_directory(const gchar *dir)
 {
-	SetCurrentDirectory(dir);
+	g_return_if_fail(dir != NULL);
+	TCHAR *w_dir = win32_utf8_to_tchar(dir);
+	SetCurrentDirectory(w_dir);
+	g_free(w_dir);
 }
 
 
@@ -1001,22 +1103,14 @@ gchar *win32_get_installation_dir(void)
 gchar *win32_get_user_config_dir(void)
 {
 	HRESULT hr;
-	wchar_t path[MAX_PATH];
+	TCHAR path[MAX_PATH];
 
-	hr = SHGetFolderPathAndSubDirW(NULL, CSIDL_APPDATA | CSIDL_FLAG_CREATE, NULL, SHGFP_TYPE_CURRENT, L"geany", path);
+	hr = SHGetFolderPathAndSubDir(NULL, CSIDL_APPDATA | CSIDL_FLAG_CREATE, NULL, SHGFP_TYPE_CURRENT, TEXT("geany"), path);
 	if (SUCCEEDED(hr))
 	{
-		// GLib always uses UTF-8 for filename encoding on Windows
-		int u8_size = WideCharToMultiByte(CP_UTF8, 0, path, -1, NULL, 0, NULL, NULL);
-		if (u8_size > 0)
-		{
-			gchar *u8_path = g_malloc0(u8_size + 1);
-			if (u8_path != NULL &&
-				WideCharToMultiByte(CP_UTF8, 0, path, -1, u8_path, u8_size, NULL, NULL))
-			{
-				return u8_path;
-			}
-		}
+		gchar *utf8_str = win32_tchar_to_utf8(path);
+		if (utf8_str != NULL)
+			return utf8_str;
 	}
 
 	// glib fallback