IO: added fs_writeable function

Author: mgerhardy

src/modules/io/Filesystem.cpp

@@ -27,6 +27,7 @@ extern bool fs_mkdir(const char *path);
 extern bool fs_rmdir(const char *path);
 extern bool fs_unlink(const char *path);
 extern bool fs_exists(const char *path);
+extern bool fs_writeable(const char *path);
 extern bool fs_hidden(const char *path);
 extern bool fs_chdir(const char *path);
 extern core::String fs_realpath(const char *path);

src/modules/io/system/Null.cpp

@@ -33,6 +33,10 @@ bool fs_exists(const char *path) {
 	return false;
 }
 
+bool fs_writeable(const char *path) {
+	return false;
+}
+
 bool fs_chdir(const char *path) {
 	return false;
 }

src/modules/io/system/Unix.cpp

@@ -281,6 +281,10 @@ core::String fs_readlink(const char *path) {
 	return buf;
 }
 
+bool fs_writeable(const char *path) {
+	return access(path, W_OK) == 0;
+}
+
 static int fs_scandir_filter(const struct dirent *dent) {
 	return strcmp(dent->d_name, ".") != 0 && strcmp(dent->d_name, "..") != 0;
 }

src/modules/io/system/Windows.cpp

@@ -135,14 +135,22 @@ bool fs_hidden(const char *path) {
 bool fs_exists(const char *path) {
 	WCHAR *wpath = io_UTF8ToStringW(path);
 	priv::denormalizePath(wpath);
-	const int ret = _waccess(wpath, 00);
+	const int ret = _waccess(wpath, 0);
 	SDL_free(wpath);
 	if (ret != 0) {
 		Log::debug("Failed to access %s: %s", path, strerror(errno));
 	}
 	return ret == 0;
 }
 
+bool fs_writeable(const char *path) {
+	WCHAR *wpath = io_UTF8ToStringW(path);
+	priv::denormalizePath(wpath);
+	const int ret = _waccess(wpath, 2);
+	SDL_free(wpath);
+	return ret == 0;
+}
+
 bool fs_chdir(const char *path) {
 	WCHAR *wpath = io_UTF8ToStringW(path);
 	priv::denormalizePath(wpath);