Refactor spawn.c

This moves some code of parse_command() out into a new helper function.
No functional changes intended.

Signed-off-by: Uli Schlachter <psychon@znc.in>

spawn.c

@@ -369,6 +369,48 @@ spawn_callback(gpointer user_data)
         unsetenv("DESKTOP_STARTUP_ID");
 }
 
+/** Convert a Lua table of string to a char** array.
+ * \param L The Lua VM state.
+ * \param idx The index of the table that we should parse
+ * \return The argv array.
+ */
+static gchar **
+parse_table_array(lua_State *L, int idx, GError **error)
+{
+    gchar **argv = NULL;
+    size_t i, len;
+
+    luaL_checktype(L, idx, LUA_TTABLE);
+    idx = luaA_absindex(L, idx);
+    len = luaA_rawlen(L, idx);
+
+    /* First verify that the table is sane: All integer keys must contain
+     * strings. Do this by pushing them all onto the stack.
+     */
+    for (i = 0; i < len; i++)
+    {
+        lua_rawgeti(L, idx, i+1);
+        if (lua_type(L, -1) != LUA_TSTRING)
+        {
+            g_set_error(error, G_SPAWN_ERROR, 0,
+                    "Non-string argument at table index %zd", i+1);
+            return NULL;
+        }
+    }
+
+    /* From this point on nothing can go wrong and so we can safely allocate
+     * memory.
+     */
+    argv = g_new0(gchar *, len + 1);
+    for (i = 0; i < len; i++)
+    {
+        argv[len - i - 1] = g_strdup(lua_tostring(L, -1));
+        lua_pop(L, 1);
+    }
+
+    return argv;
+}
+
 /** Parse a command line.
  * \param L The Lua VM state.
  * \param idx The index of the argument that we should parse
@@ -378,7 +420,6 @@ static gchar **
 parse_command(lua_State *L, int idx, GError **error)
 {
     gchar **argv = NULL;
-    idx = luaA_absindex(L, idx);
 
     if (lua_isstring(L, idx))
     {
@@ -388,31 +429,7 @@ parse_command(lua_State *L, int idx, GError **error)
     }
     else if (lua_istable(L, idx))
     {
-        size_t i, len = luaA_rawlen(L, idx);
-
-        /* First verify that the table is sane: All integer keys must contain
-         * strings. Do this by pushing them all onto the stack.
-         */
-        for (i = 0; i < len; i++)
-        {
-            lua_rawgeti(L, idx, i+1);
-            if (lua_type(L, -1) != LUA_TSTRING)
-            {
-                g_set_error(error, G_SPAWN_ERROR, 0,
-                        "Non-string argument at table index %zd", i+1);
-                return NULL;
-            }
-        }
-
-        /* From this point on nothing can go wrong and so we can safely allocate
-         * memory.
-         */
-        argv = g_new0(gchar *, len + 1);
-        for (i = 0; i < len; i++)
-        {
-            argv[len - i - 1] = g_strdup(lua_tostring(L, -1));
-            lua_pop(L, 1);
-        }
+        argv = parse_table_array(L, idx, error);
     }
     else
     {