refactored code a bit to avoid duplication

blitbuffer.c

@@ -20,9 +20,7 @@
 #include <string.h>
 #include "blitbuffer.h"
 
-static int newBlitBuffer(lua_State *L) {
-	int w = luaL_checkint(L, 1);
-	int h = luaL_checkint(L, 2);
+int newBlitBufferNative(lua_State *L, int w, int h, BlitBuffer **newBuffer) {
 	BlitBuffer *bb = (BlitBuffer*) lua_newuserdata(L, sizeof(BlitBuffer));
 	luaL_getmetatable(L, "blitbuffer");
 	lua_setmetatable(L, -2);
@@ -36,9 +34,18 @@ static int newBlitBuffer(lua_State *L) {
 	}
 	memset(bb->data, 0, bb->pitch * h);
 	bb->allocated = 1;
+	if(newBuffer != NULL) {
+		*newBuffer = bb;
+	}
 	return 1;
 }
 
+static int newBlitBuffer(lua_State *L) {
+	int w = luaL_checkint(L, 1);
+	int h = luaL_checkint(L, 2);
+	return newBlitBufferNative(L, w, h, NULL);
+}
+
 static int getWidth(lua_State *L) {
 	BlitBuffer *bb = (BlitBuffer*) luaL_checkudata(L, 1, "blitbuffer");
 	lua_pushinteger(L, bb->w);

blitbuffer.h

@@ -31,6 +31,7 @@ typedef struct BlitBuffer {
 	uint8_t allocated;
 } BlitBuffer;
 
+int newBlitBufferNative(lua_State *L, int w, int h, BlitBuffer **newBuffer);
 int luaopen_blitbuffer(lua_State *L);
 
 #endif

ft.c

@@ -112,18 +112,11 @@ static int renderGlyph(lua_State *L) {
 
 	lua_newtable(L);
 
-	BlitBuffer *bb = (BlitBuffer*) lua_newuserdata(L, sizeof(BlitBuffer));
-	luaL_getmetatable(L, "blitbuffer");
-	lua_setmetatable(L, -2);
-
-	bb->w = w;
-	bb->pitch = (w + 1) / 2;
-	bb->h = h;
-	bb->data = malloc(bb->pitch * h);
-	if(bb->data == NULL) {
-		return luaL_error(L, "cannot allocate memory for blitbuffer");
+	BlitBuffer *bb;
+	int result = newBlitBufferNative(L, w, h, &bb);
+	if(result != 1) {
+		return result;
 	}
-	bb->allocated = 1;
 
 	lua_setfield(L, -2, "bb");