所以,我正在尝试在 golang 中制作一个简单的 AOT 虚拟机,它在输入时读取字节码文件。我基本上是在尝试将字节写入文件,然后使用 ioutil
读取它们,但是我遇到了 null 取消引用错误。
这是我用于写入文件的 python 代码:
btest = open("test.thief", "w")
bytes_to_write = bytearray([1, 44, 56, 55, 55, 0])
btest.write(bytes_to_write)
btest.close()
这是我用来读取字节的 go 文件中的代码
package main
import (
"fmt"
"io/ioutil"
"os"
)
func main() {
//gets command line args
userArgs := os.Args[1:]
bytes, err := ioutil.ReadFile(userArgs[0]) // just pass the file name
if err != nil {
fmt.Print(err)
}
fmt.Println(bytes)
machine := NewEnv()
ReadBytes(machine, bytes)
}
这是我得到的错误:
Joshuas-MacBook-Pro-3:thief Josh$ ./bin/Thief test.thief
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xb code=0x1 addr=0x0 pc=0x2af3]
goroutine 1 [running]:
main.ReadBytes(0xc82000e390, 0xc82000c480, 0x6, 0x206)
/Users/Josh/thief/src/Thief/read.go:26 +0x353
main.main()
/Users/Josh/thief/src/Thief/Main.go:18 +0x1f2
我也试过用 python 代码以二进制模式打开文件,但它产生了同样的错误。基本上这样做的目标是我希望能够提取字节数组,但也有一种编写主题的方法。
我写错字节了吗?
这是十六进制转储:
012c 3837 3700
编辑:
这是我剩下的go文件
opfuncs.go
package main
//file for machine functions and operations
//prints string format of some bytes
func print(env Env, data []byte) {
fmt.Println(string(data))
}
var OPERS map[byte]func(Env, []byte)
//0 is reserved as the null terminator
func init(){
OPERS = map[byte]func(Env, []byte){
1:print,
}
}
env.go
package main
//file for the env struct
type Env struct {
items map[string]interface{}
}
func NewEnv() Env {
return Env{make(map[string]interface{})}
}
//general getter
func (self *Env) get(key string) interface{} {
val, has := self.items[key]
if has {
return val
} else {
return nil
}
}
//general setter
func (self *Env) set(key string, value interface{}) {
self.items[key] = value
}
func (self *Env) contains(key string) bool {
_, has := self.items[key]
return has
}
func (self *Env) declare(key string) {
self.items[key] = Null{}
}
func (self *Env) is_null(key string) bool {
_, ok := self.items[key].(Null)
return ok
}
//deletes an item from storage
func (self *Env) del(key string) {
delete(self.items, key)
}
阅读.go
package main
//file that contains the reading function for the VM
func ReadBytes(env Env, in []byte) {
bytes := make([]byte, 1)
fn := byte(0)
mode := 0
for i:=0;i<len(in);i++ {
switch mode {
case 0:
fn = byte(i)
mode = 1
case 1:
if i != len(in)-1 {
if in[i+1] == 0 {
bytes = append(bytes, in[i])
mode = 2
} else {
bytes = append(bytes, in[i])
}
} else {
bytes = append(bytes, in[i])
}
case 2:
OPERS[fn](env, bytes)
mode = 0
fn = byte(0)
bytes = make([]byte, 1)
}
}
}
最佳答案
如果使用 Python 3,文件必须以二进制模式打开:
btest = open("test.thief", "wb")
关于python - 写入后无法使用 go 从文件中读取字节,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/41647802/