How to compress multiple folders into one archive? - delphi

I have some compression components (like KAZip, JVCL, zLib) and exactly know how to use them to compress files, but i want to compress multiple folders into one single archive and keep folders structure after extract, how can i do it?
in all those components i just can give a list of files to compress, i can not give struct of folders to extract, there is no way (or i couldn't find) to tell every file must be extracted where:
i have a file named myText.txt in folder FOLDER_A and have a file with same name myText.txt in folder FOLDER_B:
|
|__________ FOLDER_A
| |________ myText.txt
|
|__________ FOLDER_B
| |________ myText.txt
|
i can give a list of files to compress: myList(myText.txt, myText.txt) but i cant give the structure for uncompress files, what is best way to found which file belongs to which folder?

The zip format just does not have folders. Well, it kinda does, but they are kind of empty placeholders, only inserted if you need metadata storage like user access rights. But other than those rather rare advanced things - there is no need for folders at all. What is really done - and what you can observe opening zip file in the notepad and scrolling to the end - is that each file has its path in it, starting with "archive root". In your exanple the zip file should have two entries (two files):
FOLDER_A/myText.txt
FOLDER_B/myText.txt
Note, that the separators used are true slashes, common to UNIX world, not back-slashes used in DOS/Windows world. Some libraries would fix back-slashes it for you, some would not - just do your tests.
Now, let's assume that that tree is contained in D:\TEMP\Project - just for example.
D:\TEMP\Project\FOLDER_A\myText.txt
D:\TEMP\Project\FOLDER_B\myText.txt
There are two more questions (other than path separators): are there more folders within D:\TEMP\Project\ that should be ignored, rather than zipped (like maybe D:\TEMP\Project\FOLDER_C\*.* ? and does your zip-library have direct API to pack the folders wit hall its internal subfolder and files or should you do it file by file ?
Those three questions you should ask yourself and check while choosing the library. The code drafts would be somewhat different.
Now let's start drafting for the libraries themselves:
The default variant is just using Delphi itself.
Enumerate the files in the folder: http://docwiki.embarcadero.com/CodeExamples/XE3/en/DirectoriesAndFilesEnumeraion_(Delphi)
If that enumeration results in absolute paths then strip the common D:\TEMP\Project from the beginning: something like If AnsiStartsText('D:\TEMP\Project\', filename) then Delete(filename, 1, Length('D:\TEMP\Project\'));. You should get paths relative to chosen containing place. Especially if you do not compress the whole path and live some FOLDER_C out of archive.
Maybe you should also call StringReplace to change '\' into '/' on filenames
then you can zip them using http://docwiki.embarcadero.com/Libraries/XE2/en/System.Zip.TZipFile.Add - take care to specify correct relative ArchiveFileName like aforementioned FOLDER_A/myText.txt
You can use ZipMaster library. It is very VCL-bound and may cause troubles using threads or DLLs. But for simple applications it just works. http://www.delphizip.org/
Last version page have links to "setup" package which had both sources, help and demos. Among demos there is an full-featured archive browser, capable of storing folders. So, you just can read the code directly from it. http://www.delphizip.org/191/v191.html
You talked about JVCL, that means you already have Jedi CodeLib installed. And JCL comes with a proper class and function, that judging by name can directly do what you want it too: function TJclSevenzipCompressArchive.AddDirectory(const PackedName: WideString; const DirName: string = ''; RecurseIntoDir: Boolean = False; AddFilesInDir: Boolean = False): Integer;
Actually all those libraries are rather similar on basic level, when i made XLSX export i just made a uniform zipping API, that is used with no difference what an actual zipping engine is installed. But it works with in-memory TStream rather than on-disk files, so would not help you directly. But i just learned than apart of few quirks (like instant vs postponed zipping) on ground level all those libs works the same.

Related

Consuming contents of declare_directory

I have rule A implemented with a macro that uses declare_directory to produce a set of files:
output = ctx.actions.declare_directory("selected")
Names of those files are not known in advance. The implementation returns the directory created by declare_directory with the following:
return DefaultInfo(
files = depset([output]),
)
Rule A is included in "srcs" attribute of rule B. Rule B is also implemented with a macro. Unfortunately the list of files passed to B implementation through "srcs" attribute only contains the "selected" directory created by rule A instead of files residing in that directory.
I know that Args class supports expansion of directories so I could pass names of all files in "selected" directory to a single action. What I need, however, is a separate action for every individual file for parallelism and caching. What is the best way to achieve that?
This is one of the intended use cases of directory outputs (called TreeArtifacts in the implementation), and it's implemented using ActionTemplate:
https://github.com/bazelbuild/bazel/blob/c2100ad420618bb53754508da806b5624209d9be/src/main/java/com/google/devtools/build/lib/actions/ActionTemplate.java#L24-L57
However, this is not exposed to Starlark, and has only a couple usages currently, in the Android rules AndroidBinary.java and C++ rules CcCompilationHelper.java. The Android rules and C++ rules are going to be migrated over to Starlark, so this functionality might eventually be made available in Starlark, but I'm not sure of any concrete timelines. It would probably be good to file a feature request on Github.

What is the recommended way to make & load a library?

I want to make a small "library" to be used by my future maxima scripts, but I am not quite sure on how to proceed (I use wxMaxima). Maxima's documentation covers the save(), load() and loadFile() functions, yet does not provide examples. Therefore, I am not sure whether I am using the proper/best way or not. My current solution, which is based on this post, stores my library in the *.lisp format.
As a simple example, let's say that my library defines the cosSin(x) function. I open a new session and define this function as
(%i0) cosSin(x) := cos(x) * sin(x);
I then save it to a lisp file located in the /tmp/ directory.
(%i1) save("/tmp/lib.lisp");
I then open a new instance of maxima and load the library
(%i0) loadfile("/tmp/lib.lisp");
The cosSin(x) is now defined and can be called
(%i1) cosSin(%pi/4)
(%o1) 1/2
However, I noticed that a substantial number of the libraries shipped with maxima are of *.mac format: the /usr/share/maxima/5.37.2/share/ directory contains 428 *.mac files and 516 *.lisp files. Is it a better format? How would I generate such files?
More generally, what are the different ways a library can be saved and loaded? What is the recommended approach?
Usually people put the functions they need in a file name something.mac and then load("something.mac"); loads the functions into Maxima.
A file can contain any number of functions. A file can load other files, so if you have somethingA.mac and somethingB.mac, then you can have another file that just says load("somethingA.mac"); load("somethingB.mac");.
One can also create Lisp files and load them too, but it is not required to write functions in Lisp.
Unless you are specifically interested in writing Lisp functions, my advice is to write your functions in the Maxima language and put them in a file, using an ordinary text editor. Also, I recommend that you don't use save to save the functions to a file as Lisp code; just type the functions into a file, as Maxima code, with a plain text editor.
Take a look at the files in share to get a feeling for how other people have gone about it. I am looking right now at share/contrib/ggf.mac and I see it has a lengthy comment header describing its purpose -- such comments are always a good idea.
For principiants, like me,
Menu Edit:configure:Startup commands
Copy all the functions you have verified in the first box (this will write your wxmaxima-init.mac in the location indicated below)
Restart Wxmaxima.
Now you can access the functions whitout any load() command

How to define and use precompiled variable in delphi directives

I want to define a precompile string variable and use it in {$include} directive in delphi, for example:
{$define FILE_NAME "lockfile"}
{$include FILE_NAME'.txt.1'}
{$include FILE_NAME'.txt.2'}
...
For security reasons (this is part of our licensing system), we don't want to use normal strings and file reading functions. Is there any capability for this purpose in Delphi?
The $INCLUDE directive does not support indirection on the file name. So, the following code:
const
someconst = 'foo';
{$INCLUDE someconst}
leads to the following error:
F1026 File not found: 'someconst.pas'
If you must use an include file, you must apply the indirection by some other means. One way could be to use the fact that the compiler will search for the included file by looking on the search path. So, if you place each client specific include file in a different directory, then you can add the client specific directory to the search path as part of your build process.
FWIW, I find it hard to believe that this will make your program more immune to hacking. I think that a more likely outcome is that your program will be just as susceptible to hacking, but that it will become much more difficult and error prone for you to build and distribute the program.
You requirement may be better satisfied by the proper use of a VCS system. You need "branches" for every customer where customer-specific files contains customer-specific data. This will avoid to litter your code with complex directive to manage each customer - file names stays the same, just their content is different in each branch. Adding a new customer just requires to create a new branch and update files there.
Then you just need get each branch and compile it for each customer to get the final executable(s) with customer specific data built in.

Lua - My documents path and file creation date

I'm planning to do a program with Lua that will first of all read specific files
and get information from those files. So my first question is whats the "my documents" path name? I have searched a lot of places, but I'm unable to find anything. My second question is how can I use the first four letters of a file name to see which one is the newest made?
Finding the files in "my documents" then find the newest created file and read it.
The reading part shouldn't be a problem, but navigating to "my documents" and finding the newest created file in a folder.
For your first question, depends how robust you want your script to be. You could use Lua's builtin os.getenv() to get a variety of environment vars related to user, such as USERNAME, USERPROFILE, HOMEDRIVE, HOMEPATH. Example:
username = os.getenv('USERNAME')
dir = 'C:\\users\\' .. username .. '\\Documents'
For the second question, there is no builtin mechanism in Windows to have the file creation or modification timestamp as part of the filename. You could read the creation or modification timestamp, via a C extension you create or using an existing Lua library like lfs. Or you could read the contents of a folder and parse the filenames if they were named according to the pattern you mention. Again there is nothing built into Lua to do this, you would either use os.execute() or lfs or, again, your own C extension module, or combinations of these.

Find long (>255) filenames

There are some folder with more than 100 files on it.
But all files and folders names broken with wrong encoding names (UTF->ANSI).
"C:\...\Госдача-Лечебни корпус\вертолетка\Госдача-Лечебни корпус\Госдача-Лечебни корпус\вертолетка\Госдача-Лечебни корпус\вертолетка\Госдача-Лечебни корпус\Госдача-Лечебни корпус\Госдача-Лечебни корпус\вертолетка\Госдача-Лечебни корпус\Госдача-Лечебни корпус\вертолетка\Госдача-Лечебни корпус\..."
Regular function Utf8ToAnsi finxing it, but FindFirst can't search folders with names longer than 255 symbols.
It gaves me only 70/100 files.
FindFirst wraps the Win32 API function FindFirstFile, and the Unicode version of that function can search paths up to 32,767 characters long if you prepend \\?\ to the path you're passing in, like \\?\C:\Folder\Folder\*.
Since Delphi 2009 and newer call the Unicode functions for you, you can just use FindFirst and co there. For Delphi 2007 and earlier (ANSI versions), you'll need to call FindFirstFile/FindNextFile/FindClose from Windows.pas directly. For more information check the Naming a file section of the platform SDK.
Do note that using \\?\ disables various bits of path processing though, so make sure it's a fully qualified path without any '.' or '..' entries. You can use the same trick to open file streams, rename, or copy files with longer paths.
The shell (Explorer) doesn't support this though, so you still need to limit those to at most MAX_PATH characters for things like SHFileOperation (to delete to the recycle bin) or ShellExecute. In many cases you can work around the problem by passing in the DOS 8.3 names instead of the long ones. FindFirst's TSearchRec doesn't expose the short names, but FindFirstFile's TWin32FindData structure does as cAlternateFileName.
Change the current directory (ChDir) to the deepest one you know about, and then pass a relative path to FindFirst or FindFirstFile.
No path component in that file name is longer than MAX_PATH characters, so you should be able to work your way into the directories one step at a time.
Beware that multithreaded programs may be sensitive to changes in the current directory since a process has only one current directory shared by all the threads.

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