JSCTypes中的C ++ char指针-LPSTR缓冲区的JavaScript字符串 [英] Javascript String to C++ char pointer -LPSTR buffer in JSCTypes

问题描述

我正在使用JSCTypes从JavaScript访问DLL。我必须通过将字符缓冲区传递给以下API来接收数据：

  __ declspec（dllexport）WORD WINAPI receive（LPWORD lpwBufferSize， 
 LPSTR lpsBuffer）; 
  

我的jsctypes看起来像这样，

  let receive = libs.dll.declare（receive，
 ctypes.stdcall_abi，
 ctypes.int32_t，//返回类型 - 返回码
 ctypes .int32_t.ptr，//缓冲区大小
 ctypes.char.ptr，//缓冲区
）; 
 var bufferSize = new ctypes.int32_t（3000000）.address（）; // 3000000 
 var buffer = new ctypes.char（）。address（）; 
让rvopen = receive（bufferSize，buffer）; 
 return buffer.readString（）
  

使用上面的代码，我可以接收第一个时间正确，但xulrunner在接收函数调用后崩溃。
我试图重现这个产生这个问题与Windows上可用的常见DLL。这引发了一个异常，
未被捕获的异常：TypeError：ctypes.char.array（500）.address不是一个函数

$ $ p $ $ $ $ c> var hostName = exports.getString = function（）{
let lib = ctypes.open（'Ws2_32.dll'）;
let gethostname = lib.declare（gethostname，
ctypes.default_abi，
ctypes.int，
ctypes.char.ptr，
ctypes.int）;
var myArray = ctypes.char.array（500）.address（）;
gethostname（myArray，500）;
返回myArray.readString（）;
};

如果我放弃地址API调用并按如下方式尝试：

  var myArray = ctypes.char.array（64）; 
  

我遇到这个问题，虽然在C ++数组中被认为是指针。
$ blockquote
未捕获的异常：类型错误：预期类型指针，在文件''的第0行，第0列中得到ctypes.char.array（640000）'

我无法访问任何dll的源代码。我只有DLL的包含文件（.h）。我是一个Java开发人员，不知道我是否可以在没有源代码的情况下进行调试
任何帮助表示感谢！

解决方案

终于找到了解决办法，

 < code> 
 let charArray = ctypes.ArrayType（ctypes.char）; 
 let myArray = new charArray（500）; 
< / code> 
  

和函数原型是一样的

I am accessing the DLL from JavaScript using JSCTypes. I have to receive data by passing a character buffer to the following API,

__declspec(dllexport) WORD WINAPI receive( LPWORD  lpwBufferSize,
                                           LPSTR   lpsBuffer);

My jsctypes looks like this,

let receive = libs.dll.declare("receive",
                               ctypes.stdcall_abi,  
                               ctypes.int32_t,           // Return type - return code
                               ctypes.int32_t.ptr,       // buffer size
                               ctypes.char.ptr,          // Buffer
                               );
var bufferSize = new ctypes.int32_t(3000000).address(); //3000000
var buffer = new ctypes.char().address();
let rvopen = receive(bufferSize, buffer);
return buffer.readString()

With above code, I could receive data for the first time correctly but xulrunner crashes on receive function call in the subsequent times. I tried to reproduce this produce this issue with a common DLL available on windows. This throws an exception, uncaught exception: TypeError: ctypes.char.array(500).address is not a function

var hostName = exports.getString = function() {
    let lib = ctypes.open('Ws2_32.dll');
    let gethostname = lib.declare("gethostname",
                                  ctypes.default_abi,
                                  ctypes.int,
                                  ctypes.char.ptr,
                                  ctypes.int);
    var myArray = ctypes.char.array(500).address();
    gethostname(myArray, 500);
    return myArray.readString();
};

If I drop the address API call and try it as below,

var myArray = ctypes.char.array(64);

I run into this issue, although in C++ arrays are considered as pointers.

'uncaught exception: TypeError: expected type pointer, got ctypes.char.array(640000)' in file '' at line 0, col 0

I don't have access to any of the dll's source code. I just have the include file(.h) for the DLL. I am a Java developer and not sure if I can debug without the source code Any help appreciated!

解决方案

Have finally found a solution,

<code>
 let charArray= ctypes.ArrayType(ctypes.char);
 let myArray = new charArray(500);      
</code>

and the function prototype is the same

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