Rework unicode encoding/decoding (Windows)

src/host/os_chdir.c

@@ -14,8 +14,14 @@ int do_chdir(lua_State* L, const char* path)
 	(void)(L);  /* warning: unused parameter */
 
 #if PLATFORM_WINDOWS
-	z = SetCurrentDirectoryW(utf8_towide(L, path));
+	wchar_t wide_buffer[PATH_MAX];
-	lua_pop(L, 1);
+	if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_buffer, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode path");
+		return lua_error(L);
+	}
+
+	z = SetCurrentDirectoryW(wide_buffer);
 #else
 	z = !chdir(path);
 #endif

src/host/os_copyfile.c

@@ -14,8 +14,22 @@ int os_copyfile(lua_State* L)
 	const char* dst = luaL_checkstring(L, 2);
 
 #if PLATFORM_WINDOWS
-	z = CopyFileW(utf8_towide(L, src), utf8_towide(L, dst), FALSE);
+	wchar_t wide_src[PATH_MAX];
-	lua_pop(L, 2);
+	wchar_t wide_dst[PATH_MAX];
+
+	if (MultiByteToWideChar(CP_UTF8, 0, src, -1, wide_src, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode source path");
+		return lua_error(L);
+	}
+
+	if (MultiByteToWideChar(CP_UTF8, 0, dst, -1, wide_dst, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode source path");
+		return lua_error(L);
+	}
+
+	z = CopyFileW(wide_src, wide_dst, FALSE);
 #else
 	lua_pushfstring(L, "cp \"%s\" \"%s\"", src, dst);
 	z = (system(lua_tostring(L, -1)) == 0);

src/host/os_getcwd.c

@@ -24,9 +24,9 @@ int do_getcwd(char* buffer, size_t size)
 	int result;
 
 #if PLATFORM_WINDOWS
-	wchar_t wbuffer[MAX_PATH];
+	wchar_t wbuffer[PATH_MAX];
 
-	result = (GetCurrentDirectoryW(MAX_PATH, wbuffer) != 0);
+	result = (GetCurrentDirectoryW(PATH_MAX, wbuffer) != 0);
 	if (result) {
 		WideCharToMultiByte(CP_UTF8, 0, wbuffer, -1, buffer, size, NULL, NULL);
 

src/host/os_isdir.c

@@ -19,7 +19,12 @@ int os_isdir(lua_State* L)
 #ifdef _WIN32
 	int attr;
 
-	const wchar_t* wide_path = utf8_towide(L, path);
+	wchar_t wide_path[PATH_MAX];
+	if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_path, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode path");
+		return lua_error(L);
+	}
 #endif
 
 	/* empty path is equivalent to ".", must be true */
@@ -45,10 +50,6 @@ int os_isdir(lua_State* L)
 		lua_pushboolean(L, 0);
 	}
 
-#ifdef _WIN32
-	lua_remove(L, -2); /* pop wide string */
-#endif
-
 	return 1;
 }
 

src/host/os_isfile.c

@@ -21,9 +21,15 @@ int do_isfile(lua_State* L, const char* filename)
 	(void)(L);  /* warning: unused parameter */
 
 #if PLATFORM_WINDOWS
-	DWORD attrib = GetFileAttributesW(utf8_towide(L, filename));
+	wchar_t wide_path[PATH_MAX];
-	lua_pop(L, 1);
 
+	if (MultiByteToWideChar(CP_UTF8, 0, filename, -1, wide_path, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode filepath");
+		return lua_error(L);
+	}
+
+	DWORD attrib = GetFileAttributesW(wide_path);
 	if (attrib != INVALID_FILE_ATTRIBUTES)
 	{
 		return (attrib & FILE_ATTRIBUTE_DIRECTORY) == 0;

src/host/os_islink.c

@@ -14,9 +14,14 @@ int os_islink(lua_State* L)
 
 #if PLATFORM_WINDOWS
 	{
-		DWORD attr = GetFileAttributesW(utf8_towide(L, path));
+		wchar_t wide_path[PATH_MAX];
-		lua_pop(L, 1);
+		if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_path, PATH_MAX) == 0)
+		{
+			lua_pushstring(L, "unable to encode path");
+			return lua_error(L);
+		}
 
+		DWORD attr = GetFileAttributesW(wide_path);
 		if (attr != INVALID_FILE_ATTRIBUTES) {
 			lua_pushboolean(L, (attr & FILE_ATTRIBUTE_REPARSE_POINT) != 0);
 			return 1;

src/host/os_match.c

@@ -21,11 +21,17 @@ typedef struct struct_MatchInfo
 int os_matchstart(lua_State* L)
 {
 	const char* mask = luaL_checkstring(L, 1);
+
+	wchar_t wide_mask[PATH_MAX];
+	if (MultiByteToWideChar(CP_UTF8, 0, mask, -1, wide_mask, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode mask");
+		return lua_error(L);
+	}
+
 	MatchInfo* m = (MatchInfo*)malloc(sizeof(MatchInfo));
 
-	m->handle = FindFirstFileW(utf8_towide(L, mask), &m->entry);
+	m->handle = FindFirstFileW(wide_mask, &m->entry);
-	lua_pop(L, 1);
-
 	m->is_first = 1;
 	lua_pushlightuserdata(L, m);
 	return 1;
@@ -43,7 +49,15 @@ int os_matchdone(lua_State* L)
 int os_matchname(lua_State* L)
 {
 	MatchInfo* m = (MatchInfo*)lua_touserdata(L, 1);
-	utf8_fromwide(L, m->entry.cFileName);
+
+	char filename[PATH_MAX];
+	if (WideCharToMultiByte(CP_UTF8, 0, m->entry.cFileName, -1, filename, PATH_MAX, NULL, NULL) == 0)
+	{
+		lua_pushstring(L, "unable to decode filename");
+		return lua_error(L);
+	}
+
+	lua_pushstring(L, filename);
 	return 1;
 }
 

src/host/os_rmdir.c

@@ -14,8 +14,14 @@ int os_rmdir(lua_State* L)
 	const char* path = luaL_checkstring(L, 1);
 
 #if PLATFORM_WINDOWS
-	z = RemoveDirectoryW(utf8_towide(L, path));
+	wchar_t wide_path[PATH_MAX];
-	lua_pop(L, 1);
+	if (MultiByteToWideChar(CP_UTF8, 0, path, -1, wide_path, PATH_MAX) == 0)
+	{
+		lua_pushstring(L, "unable to encode path");
+		return lua_error(L);
+	}
+
+	z = RemoveDirectoryW(wide_path);
 #else
 	z = (0 == rmdir(path));
 #endif

src/host/premake.h

@@ -87,12 +87,6 @@ void do_normalize(lua_State* L, char* buffer, const char* path);
 int do_pathsearch(lua_State* L, const char* filename, const char* path);
 void do_translate(char* value, const char sep);
 
-/* Unicode conversion helper functions (required for Windows systems) */
-#ifdef PLATFORM_WINDOWS
-const char* utf8_fromwide(lua_State* L, const wchar_t* wstr);
-const wchar_t* utf8_towide(lua_State* L, const char* str);
-#endif
-
 /* Built-in functions */
 int criteria_compile(lua_State* L);
 int criteria_delete(lua_State* L);

src/host/utf8handling.c

@@ -1,33 +0,0 @@
-/**
- * \file   utf8handking.c
- * \brief  Handles conversions between Unicode (UTF-8) and system native encoding (wide chars on Windows)
- * \author Copyright (c) 2017 Jérôme Leclercq and the Premake project
- */
-
-#include "premake.h"
-#include "stdlib.h"
-
-#ifdef PLATFORM_WINDOWS
-const char* utf8_fromwide(lua_State* L, const wchar_t* wstr)
-{
-	int size_required = WideCharToMultiByte(CP_UTF8, 0, wstr, -1, NULL, 0, NULL, NULL);
-
-	char* unicode_str = (char*) malloc(size_required * sizeof(char));
-	WideCharToMultiByte(CP_UTF8, 0, wstr, -1, unicode_str, size_required, NULL, NULL);
-
-	lua_pushstring(L, unicode_str);
-	free(unicode_str);
-	
-	return unicode_str;
-}
-
-const wchar_t* utf8_towide(lua_State* L, const char* str)
-{
-	int size_required = MultiByteToWideChar(CP_UTF8, 0, str, -1, NULL, 0);
-
-	wchar_t* wide_string = (wchar_t*) lua_newuserdata(L, size_required * sizeof(wchar_t));
-	MultiByteToWideChar(CP_UTF8, 0, str, -1, wide_string, size_required);
-
-	return wide_string;
-}
-#endif