I'm working on a system for serialization/deserialization, and I'm trying to get some really fancy stuff going with functions. My goal is to serialize objects containing functions in a human-readable and reversible manner (the serialized files will need processing after the loadfile() step). I need a way to get the actual source of a function, and it looks like I can't always do that with debug.getinfo().
I know that debug.getinfo() will give be the file and line where it was defined (or the source of the function, depending on its origin). Is there a way I can read the function text from that file? I'd be willing to use some kind of parser utilities to do so. Maybe there are Lua packages for parsing Lua code?
Perhaps there's a way I can get loadfile() or require() to automatically retain function source somewhere?
Yes, I know you can get all sorts of information out of debug.getinfo, but it was unable to deal with functions loaded through stdin...
uberblah#glade-m:~$ lua
Lua 5.1.5 Copyright (C) 1994-2012 Lua.org, PUC-Rio
> a = function() print("hello, world!") end
> require("serpent")
> s = require("serpent")
> =s.block(debug.getinfo(a))
{
currentline = -1,
func = loadstring("LuaQ\000\000\000\000\000\000\000\000\000=stdin\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000A#\000\000#\000\000�\000\000\000\000\000\000\000\000\000\000\000print\000\000\000\000\000\000\000\000hello, world!\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000",'#serialized') --[[function: 0x2068a30]],
lastlinedefined = 1,
linedefined = 1,
namewhat = "",
nups = 0,
short_src = "stdin",
source = "=stdin",
what = "Lua"
} --[[table: 0x206cf80]]
> f = io.open("stdin", "r")
> =f
nil
SOLUTION FOR SOURCE FROM STDIN...
1) Capture all STDIN, write it to a file
2) Load the information from that file, instead of from stdin
3) debug will track the function line numbers in that file
Using debug.getinfo you can get source, linedefined, and lastlinedefined. Unless you format your code really weirdly you should be able to extract the complete code of your function from this info. There is no need to parse code, just to get the correct set of lines.
You want to disasseble the bytecode into Lua statements and expressions. Try http://chunkspy.luaforge.net/. Or maybe http://luadec.luaforge.net/ but I haven't used them so can't give much more info. Luac (Lua compiler) also has -l switch which produces assembly listing that could potentially be parsed. Then there is lbci (bhttp://www.tecgraf.puc-rio.br/~lhf/ftp/lua/#lbci). You might find Getting the AST of a function useful. Finally, I suggest you do a search for "lua decompiler".
Related
I'm using Photoshop script. I get files from folders. My problem is that when I get the files and place them in an array the array contains hidden files that are in the folder for example ".DS_Store". I can get around this by using:
if (folders[i] != "~/Downloads/start/.DS_Store"){}
But I would like to use something better as I sometimes look in lots of folders and don't know the "~/Downloads/start/" part.
I tried to use indexOf but Photoshop script does not allow indexOf. Does anybody know of a way to check if ".DS_Store" is in the string "~/Downloads/start/.DS_Store" that works in Photoshop script?
I see this answer but I don't know how to use it to test: Photoshop script to ignore .ds_store
For anyone else looking for a solution to this problem, rather than explicitly trying to skip hidden files like .DS_Store, you can use the Folder Object's getFiles() method and pass an expression to build an array of file types you actually want to open. A simple way to use this method is as follows:
// this expression will match strings that end with .jpg, .tif, or .psd and ignore the case
var fileTypes = new RegExp(/\.(jpg|tif|psd)$/i);
// declare our path
var myFolder = new Folder("~/Downloads/start/");
// create array of files utilizing the expression to filter file types
var myFiles = myFolder.getFiles(fileTypes);
// loop through all the files in our array and do something
for (i = 0; i < myFiles.length; i++) {
var fileToOpen = myFiles[i];
open(fileToOpen);
// do stuff...
}
For anybody looking I used the Polyfill found here:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf
indexOf() was added to the ECMA-262 standard in the 5th edition; as
such it may not be present in all browsers. You can work around this
by utilizing the following code at the beginning of your scripts. This
will allow you to use indexOf() when there is still no native support.
This algorithm matches the one specified in ECMA-262, 5th edition,
assuming TypeError and Math.abs() have their original values.
I am trying to identify when a file is PNG or JPG to apply it as a wallpaper. I am using the SHGetFileInfo to get the type name with the .szTypeName variable, but I just realized that it changes if the OS is in another language.
This is my code:
SHFILEINFOW fileInfo;
UINT sizeFile = sizeof(fileInfo);
UINT Flags = SHGFI_TYPENAME | SHGFI_USEFILEATTRIBUTES;
// Getting file info to find out if it has JPG or PNG format
SHGetFileInfoW(argv[1], 0, &fileInfo, sizeFile, Flags);
This is how I am validating:
if (wcscmp(fileInfo.szTypeName, L"JPG File") == 0)
{
//Code here
}
When the OS is in spanish, the value changes to "Archivo JPG" so I would have to validate against all language, and does not make sense.
Any idea what other function I can use?
This API is meant to be used to produce a user-facing string representation for known file types1). It is not meant to be used to implement code logic.
More importantly, it doesn't try to parse the file contents. It works off of the file extension alone. If you rename an Excel workbook MySpreadsheet.xlsx to MySpreadsheet.png, it will happily report, that this is a "PNG File".
The solution to your problem is simple: You don't have to do anything, other than filtering on the file extension. Use PathFindExtension (or PathCchFindExtension for Windows 8 and above) to get the file extension from a fully qualified path name.
This can fail, in case the user appended the wrong file extension. Arguably, this isn't something your application should fix, though.
As an aside, you pass SHGFI_USEFILEATTRIBUTES to SHGetFileInfoW but decided to not pass any file attributes (second argument) to the call. This is a bug. See What does SHGFI_USEFILEATTRIBUTES mean? for details.
1) It is the moral equivalent of SHGFI_DISPLAYNAME. The only thing you can do with display names is display them.
My problem is the same as the one mentioned in this answer. I've been trying to understand the code and this is what I learned:
It is failing in the file parse_xml.cgi, tries to get messages (return $message{$name}) from a file named messages (located in the html_en directory).
The $messages value comes from the method GetMessageHash in file adminprotocol-lib.pl:
sub GetMessageHash
{
return $ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"}
}
The $ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"} is set in the file streamingadminserver.pl:
$ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"} = $messages{"en"}
I dont know anything about Perl so I have no idea of what the problem can be, for what I saw $messages{"en"} has the correct value (if I do print($messages{"en"}{'SunStr'} I get the value "Sun")).
However, if I try to do print($ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"}{'SunStr'} I get nothing. Seems like $ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"} is not set
I tried this simple example and it worked fine:
$ENV{"HELLO"} = "hello";
print($ENV{"HELLO"});
and it works fine, prints "hello".
Any idea of what the problem can be?
Looks like $messages{"en"} is a HashRef: A pointer to some memory address holding a key-value-store. You could even print the associated memory address:
perl -le 'my $hashref = {}; print $hashref;'
HASH(0x1548e78)
0x1548e78 is the address, but it's only valid within the same running process. Re-run the sample command and you'll get different addresses each time.
HASH(0x1548e78) is also just a human-readable representation of the real stored value. Setting $hashref2="HASH(0x1548e78)"; won't create a real reference, just a copy of the human-readable string.
You could easily proof this theory using print $ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"} in both script.
Data::Dumper is typically used to show the contents of the referenced hash (memory location):
use Data::Dumper;
print Dumper($messages{"en"});
# or
print Dumper($ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"});
This will also show if the pointer/reference could be dereferenced in both scripts.
The solution for your problem is probably passing the value instead of the HashRef:
$ENV{"QTSSADMINSERVER_EN_SUN"} = $messages{"en"}->{SunStr};
Best Practice is using a -> between both keys. The " or ' quotes for the key also optional if the key is a plain word.
But passing everything through environment variables feels wrong. They might not be able to hold references on OSX (I don't know). You might want to extract the string storage to a include file and load it via require.
See http://www.perlmaven.com/ or http://learn.perl.org for more about Perl.
fix code:
$$ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"} = $messages{"en"};
sub GetMessageHash
{
return $$ENV{"QTSSADMINSERVER_EN_MESSAGEHASH"};
}
ref:
https://github.com/guangbin79/dss6.0.3-linux-patch
i am new to matlab. While working through the Matlab GUI, i faced a problem which is as follows..i want to have 2 figure files, with one figure file calling the other. i know that just by calling the name of the 2nd fig file from the first fig file, we can call the 2nd figure. however, i also wish to send some parameters from one fig file to another.here i need to send the arguments and also obtain these parameters so as to do further processing.i havent been able to find a solution to this problem. i would be glad if someone helps me out with this problem. thanking you in advance
There are three ways I found to do this:
Method 1: Use setappdata and getappdata like so:
setappdata(0,'some_var',value)
some_other_var = getappdata(0,'some_var')
You would use setappdata() in the m-file for fig1 to store whatever data you wanted to pass around, and then call getappdata() in another m-file to retrieve it. The argument 0 to the two functions specifies the MATLAB root workspace, which is accessible by your program everywhere (i.e. it is global). As such, when you close your figures that data will still be available. You may want to use rmappdata to remove them.
Method 2: Use guidata:
Assuming you created your GUI with GUIDE, then you have access to a structure called handles which is passed around everywhere and which you can edit, and so you can do this in a GUI callback:
handles.some_var = some_value
guidata(hObject,handles)
Then you can access handles.some_var elsewhere in some other callback (because handles is automatically passed into it for you) in your other m-file:
some_other_var = get(handles.some_var)
Method 3: Use UserData:
Store the variable you want from your first figure:
set(name_of_fig, 'UserData', some_var)
Then to get it from your other one:
some_other_var = get(name_of_fig, 'UserData')
(Disclaimer: My actual knowledge of MATLAB is not all that great, but it helps to be able to find good resources like this and this, and even this from the official docs. What I've written here may be wrong, so you should definitely consult the docs for more help.)
I would do like this (assuming you're using the GUI builder GUIDE).
Let's say that your figures/m-files are named firstFigure.fig/m and secondFigure.fig/m. In the code of firstFigure, just call secondFigure and pass your parameters as arguments:
someNumber = 1;
someText = 'test';
aMatrix = rand(3);
secondFigure(someNumber, someText, aMatrix);
The arguments will be available to secondFigure as a variable varargin in the callback functions
function varargout = secondFigure(varargin)
and
function secondFigure_OpeningFcn(hObject, eventdata, handles, varargin)
varagin is a cell structure; use cell2mat and char to convert it back:
theNumber = cell2mat(varargin(1));
theText = char(varargin(2));
theTextAgain = cell2mat(varargin(2));
theMatrix = cell2mat(varargin(3));
This may help:
http://www.mathworks.ch/matlabcentral/newsreader/view_thread/171989
The easiest method is to wrap the parameters in a cell array and send them directly to the GUI constructor. A call with two parameters might look like:
figure2({param1, param2})
Then you can unpack the arguments in the opening function (figure2_OpeningFcn) with code like:
handles.par1 = varargin{1}{1};
handles.par2 = varargin{1}{2};
These lines must be placed somewhere before the line that says guidata(hObject, handles);. Then you can access handles.par1 and handles.par2 directly in all the other callbacks.
I assume you are using GUIDE to generate your GUI. You can find figure2_OpeningFcn in figure2.m which will be located in the same directory as figure2.fig.
Note: you can also return values from a figure, returnvalue = my_figure({my_input}). If you'd like instructions on that too, leave a comment and I'll extend my answer.
I created a GUI and used uiimport to import a dataset into matlab workspace, I would like to pass this imported data to another function in matlab...How do I pass this imported dataset into another function....I tried doing diz...but it couldnt pick diz....it doesnt pick the data on the matlab workspace....any ideas??
[file_input, pathname] = uigetfile( ...
{'*.txt', 'Text (*.txt)'; ...
'*.xls', 'Excel (*.xls)'; ...
'*.*', 'All Files (*.*)'}, ...
'Select files');
uiimport(file_input);
M = dlmread(file_input);
X = freed(M);
I think that you need to assign the result of this statement:
uiimport(file_input);
to a variable, like this
dataset = uiimport(file_input);
and then pass that to your next function:
M = dlmread(dataset);
This is a very basic feature of Matlab, which suggests to me that you would find it valuable to read some of the on-line help and some of the documentation for Matlab. When you've done that you'll probably find neater and quicker ways of doing this.
EDIT: Well, #Tim, if all else fails RTFM. So I did, and my previous answer is incorrect. What you need to pass to dlmread is the name of the file to read. So, you either use uiimport or dlmread to read the file, but not both. Which one you use depends on what you are trying to do and on the format of the input file. So, go RTFM and I'll do the same. If you are still having trouble, update your question and provide details of the contents of the file.
In your script you have three ways to read the file. Choose one on them depending on your file format. But first I would combine file name with the path:
file_input = fullfile(pathname,file_input);
I wouldn't use UIIMPORT in a script, since user can change way to read the data, and variable name depends on file name and user.
With DLMREAD you can only read numerical data from the file. You can also skip some number of rows or columns with
M = dlmread(file_input,'\t',1,1);
skipping the first row and one column on the left.
Or you can define a range in kind of Excel style. See the DLMREAD documentation for more details.
The filename you pass to DLMREAD must be a string. Don't pass a file handle or any data. You will get "Filename must be a string", if it's not a string. Easy.
FREAD reads data from a binary file. See the documentation if you really have to do it.
There are many other functions to read the data from file. If you still have problems, show us an example of your file format, so we can suggest the best way to read it.