Can I overwrite a function in a compiled program with a custom version?

Question

Zhangxi Feng 2019-7-1

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/469687-can-i-overwrite-a-function-in-a-compiled-program-with-a-custom-version

评论： Zhangxi Feng 2019-7-2

I have a set of MATLAB functions with a main function that will be compiled. This program calls a function that requires the user to design part of it.

For example, I have a compiled program runFit.exe. The source code calls a wrapper.m that gets some parameters which the user defines how the parameters are actually used. I would need to include wrapper.m when I compile runFit.exe, but can the user write a new wrapper.m that gets used instead of the one compiled in the code? Or is the only way is to not compile the program?

Thanks!

Jesse

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Jan 2019-7-1

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/469687-can-i-overwrite-a-function-in-a-compiled-program-with-a-custom-version#answer_381497

This will not work. And if it works, it would conflict with the license conditions.

Do not provide parameters as M-functions, but as data files, e.g. in text format, as binary or MAT file. Then it is easy to let the user change the parameters without the need to parse and run an M-function.

8 个评论
显示 6更早的评论隐藏 6更早的评论

Steven Lord 2019-7-1

Not only is using eval bad practice, it won't work in a deployed application. From the documentation:

"The compiler secures your code against unauthorized changes. Deployable MATLAB® files are suspended or frozen at the time of compilation. This does not mean that you cannot deploy a flexible application—it means that you must design your application with flexibility in mind. If you want the end user to be able to choose between two different methods, for example, both methods must be available in the deployable archive.

The MATLAB Runtime only works on MATLAB code that was encrypted when the deployable archive was built. Any function or process that dynamically generates new MATLAB code will not work against the MATLAB Runtime."

You wrote "This parameter writing function will write input files with these parameters that are used in an another program that calculates some results that gets used in the error evaluation." Can you say more about this "another program" and how it interacts with those "input files"? Describe your workflow in a little more detail and we may be able to offer an alternate design that avoids trying to run dynamically generated MATLAB code.

Jan 2019-7-2

@Zhangxi Fend: It is a good programming practice to keep code for computations and input data separated. It is a standard for scientific software, that inputs can be provided by text or binary files. The ini files under Windows and the configuration files of Linux systems are famous examples. As soon, as the data are not included in a specific code, e.g. as Matlab code, it is possible in theory, to process them with different tools and to compare the results.

You can create your own file format and a Matlab function to import it. You can implement all kind of special cases, e.g. the number of parameters or of the needed files to be imported. There is no need to implement this as Matlab code, because these cases are such simple, that some simple tables are sufficient. This is even a good idea, if you do not compile the code. A strictly defined import functions is more reliable that creating a set of different codes to create the input data, because code must be tested exhaustively in every case. Even trivial code offers an infinite number of possible bugs. So prefer to write one code and test it exhaustively and provide the data as dull and static text/binary files.

Guillaume 2019-7-2

For example, some times it may need to write more parameters, sometimes less, and sometimes may need to write more than one file.

While allowing user to specify all this as matlab code may be the easiest for now, it's also the most fragile. The user have to be careful not to stomp over your own variables with their m code (maybe they're not even aware of your own variables, and one day a user overwrites one of your variable which slightly changes the behaviour of the code and results in slightly incorrect outputs. That goes unnoticed until the probe crashes into Mars because it's off by a few 100 meters).

The correct way to deal with this is to provide an input method completely independent of m code that allows for all these variations. It could be via configuration, a GUI, whatever. Yes, it'll be more work to start with, but ultimately a better usage experience.

Zhangxi Feng 2019-7-2

Thank you for your suggestions. I can definitely see a way to design an input file reader that dynamically recognizes the user's desired parameters and writes them according to the user's given conditions to achieve the level of flexibility for this.

请先登录，再进行评论。

Can I overwrite a function in a compiled program with a custom version?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

8 个评论
显示 6更早的评论隐藏 6更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

Can I overwrite a function in a compiled program with a custom version?

0 个评论 显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

8 个评论 显示 6更早的评论隐藏 6更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

8 个评论
显示 6更早的评论隐藏 6更早的评论