table.insert test

main.c

@@ -32,7 +32,12 @@ static size_t native_print(LVM *lvm, void *ud, size_t argn, set_LValueU *heap, L
 
 static size_t table_insert(LVM *lvm, void *ud, size_t argn, set_LValueU *heap, LRegSet *regset) {
 	LTable *tbl = (LTable*) (regset->regs[0].u & ~LTAG_MASK);
+	if(argn == 2) {
 		ltable_insert(tbl, regset->regs[1], 0);
+	} else if(argn > 2) {
+		size_t idx = lvalue_to_int32(regset->regs[1]);
+		ltable_insert(tbl, regset->regs[2], idx);
+	}
 	return 0;
 }
 

table.h

@@ -241,9 +241,20 @@ static inline size_t ltable_len(LTable *self) {
 	return ret;
 }
 
-static inline void ltable_insert(LTable *self, LValue val, size_t index) {
+static inline bool ltable_insert(LTable *self, LValue val, size_t index) {
 	lrwl_write_lock(&self->lock);
-	index = ltable_len_nolock(self) + 1;
+	size_t len = ltable_len_nolock(self);
+	if(index == 0) {
+		index = len + 1;
+	}
+	bool success = false;
+	if(index <= len + 1) {
+		for(size_t i = len; i >= index; i--) {
+			ltable_set_nolock(self, lvalue_from_int32(i + 1), ltable_get_nolock(self, lvalue_from_int32(i)));
+		}
 		ltable_set_nolock(self, lvalue_from_int32(index), val);
+		success = true;
+	}
 	lrwl_write_unlock(&self->lock);
+	return success;
 }

table_insert.lua

@@ -0,0 +1,13 @@
+t = {}
+
+for i = 50, 1, -1 do
+	table.insert(t, 1, i)
+end
+
+for i = 50, 1, -1 do
+	table.insert(t, i)
+end
+
+for i = 1, #t do
+	print(t[i])
+end