I have a script library stored in .../lib/ that I want to embed into my program. So far, that sounds simple: On Windows, I'd use Windows Resource Files - on MacOS, I'd put them into a Resource folder and use the proper API to access the current bundle and it's resources. On plain Linux, I am not too sure how to do it... But, I want to be cross-platform anyway.
Now, I know that there are tools like IncBin (https://github.com/graphitemaster/incbin) and alike, but they are best used for single files. What I have, however, might even require some kind of file system abstraction.
So here is the few guesses and estimates I did. I'd like to know if there is possibly a better solution - or others, in general.
Create a Zip file and use MiniZ in order to read it's contents off a char array. Basically, running the zip file through IncBin and passing it as a buffer to MiniZ to let me work on that.
Use an abstracted FS layer like PhysicsFS or TTVFS and add the possibility to work off a Zip file or any other kind of archive.
Are there other solutions? Thanks!
I had this same issue, and I solved it by locating the library relative to argv[0]. But that only works if you invoke the program by its absolute path -- i.e., not via $PATH in the shell. So I invoke my program by a one-line script in ~/bin, or any other directory that's in your search path:
exec /wherever/bin/program "$#"
When the program is run, argv[0] is set to "/wherever/bin/program", and it knows to look in "/wherever/lib" for the related scripts.
Of course if you're installing directly into standard locations, you can rely on the standard directory structure, such as /usr/local/bin/program for the executable and /etc/program for related scripts & config files. The technique above is just when you want to be able to install a whole bundle in an arbitrary place.
EDIT: If you don't want the one-line shell script, you can also say:
alias program=/wherever/bin/program
Related
I'm compiling CEF (Chromium Embedded Framework) for our local html5 presentation.
I should say I'm very new for all this (CEF and C++).
I've already optimized cefclient project for the presentation, but I need to embed all html/js/css/etc files into project (reading from local storage is not an option).
As I understood, I should use .zip or .pak (renamed zip) files to embed. But how can I use them inside the project?
Should I use some lib for unzipping (zlib?) or there is another popular way? And how can I be sure that files will be compiled into project?
Sorry for such basic questions but there are very few information about this (or google hates me today).
Thank you for any help!
UPD: found great tool - WBEA (http://asterclick.drclue.net/WBEA.html), it looks like exactly what I want to, but works pretty slow (with JS).
UPD 2: It turns out that there are many ways to make HTML5 desktop application, for example Node-Webkit.
Here is an article that compares some of them http://clintberry.com/2013/html5-apps-desktop-2013/
You need:
Create zip file whitin your resources.
Embed it as win32 resource (after this step you will get correct executable with .zip file inside).
Create custom scheme handler to access this zip file.
CefZipReader class will be handly to implement handler from step 3.
Look around, may be something like what you want already exist somewhere.
This sounds very similar to self extracting installers.
No need to compile anything, just concatenate the zip to the end of the executable. All you need to do is find the offset at runtime from the start of the executable. This can be done easily by writing a large magic number and looking for it later.
Example Linux:
cat app magic_number data > new_app
Example Windows:
copy app.exe /B + magic.dat /B + data.dat /B new_app.exe
I'm beginning development on an acoustic spectrum analysis tool (inspired by spek) written in C++ with gtkmm (C++ bindings for the GTK+ GUI toolkit). I would imagine that I should know how to do this by now, however...
My directory structure is a-la-GNOME, e.g src/, data/, po/, man/. The specific situation that presented the need for my inquiry is the use of a GTK UI Manager that will be located in data/ui. For this specific situation, I want to be able to load the user-interface from this file in an install-independent manner (e.g. loading of the file does not depend on a make install; the executable may be run [and load the UI file] either from src/ after running make [thus compiling the sources into the selfsame exectuable] or from its install prefix). How would I refer to the UI file in my source code (keeping in mind that the loading of the file is not performed by creating a file object (fopen(...)) but rather by passing a file location as a string argument to (UIManager).add_ui_from_file(...))?
In addition to this particular situation of a UI file, how would I do similar references to files (i.e. databases, INI files, XML schemas) by using the autotools build process? Is there a piece of relevant Automake code to quickly set up a project to use this type of directory structure?
simply try to use both files (with the un-installed taking precedence):
if(!(UIManager).add_ui_from_file(../data/ui/mygui))
(UIManager).add_ui_from_file(/incalled/location/mygui)
In Glom, I created a helper function that tries both locations, with both locations being defined in the Makefile.am (this is simpler if you have only one Makefile.am, by using non-recursive automake, which is simpler anyway):
http://git.gnome.org/browse/glom/tree/glom/glade_utils.h#n38
I want to open a number of files (log4cxx configs, other logs etc) relative to binary's location.
Unfortunately, both getwd() and getcwd() are giving me the directory, from which I try to run binary at known path, instead of giving me the path where the binary is located (and where the data is).
How to get the app's path to use it with chdir()? Any methods besides argv[0] and without trying to parse /proc/$PID/ (that's not portable enough)?
Walk the PATH and find an executable of the same name as argv[0]?
However, it would probably be better to provide the user a way to configure where the data is. An env var or config file or CL parameter or something. It's very frustrating dealing with programs that try to be helpful but are actually just stupid.
This is exactly the kind of thing autoconf lives for, and supporting those standard directories is pretty much mandatory if you ever want anyone other than the programmers who wrote your software to use it. Once set up properly, to debug out of your home directory all you have to do is pass a different --prefix= value to configure.
I have a C shell script that calls two
C programs - one after the another
with some file handling before,
in-between and afterwards.
Now, as such I have three different files - one C shell script and 2 .c files.
I need to give this script to other users. The problem is that I have to distribute three files - which the users must keep in the same folder and then execute the script.
Is there some better way to do this?
[I know I can make one C code file out of those two... but I will still be left with a shell script and a C code. Actually, the two C codes do entirely different things... so I want them to be separate]
Sounds like you're worried that your users aren't savy enough to figure out how to resolve issues like command not found errors and the like. If absolutely MUST hide "complexity" of a collection of files you could have your script create the other files. In most other circumstances I would suggest that this approach is only going to increase your support workload since semi-experienced users are less likely to know how to troubleshoot the process.
If you choose to rely on the presence of a compiler on the system that you are running on you can store the C code as a collection of cat $STRING >> file.c commands to to create your two C files, which you then compile and use.
If you would want to use pre-compiled programsn instead then the same basic process can be used except instead use xxd to both generate the strings in your script and reverse the conversion process to give you working binaries. Note: Remember to chmod the binary so that it is executable.
use shar command to create self-extracting archive.
or better yet use unzipsfx with AUTORUN option.
This provides users with ONE file, and only ONE command to execute (as opposed to one for untarring and one for execution).
NOTE: The unzip command to run should use "-n" option, that way only the first run would extract the files and the subsequent would skip the extraction.
Use a zip or tar file? And you do realize that .c files aren't executable, you need to compile & link them first?
You can include the c code inside the shell script as a here document:
#!/bin/bash
cat > code.c << EOF
line #1
line #2
...
EOF
# compile
# execute
If you want to get fancy, you can test for the existence of the executable and skip compiling them if they exists.
If you are doing much shell programming, the rest of the Advanced Bash-Scripting Guide is worth looking at as well.
C++ How to get a filename (and path) of the executing .so module in Unix?
Something similar to GetModuleFileName on Windows.
Although it is not a POSIX standard interface, the dladdr() function is available on many systems including Linux, Solaris, Darwin/Mac OS X, FreeBSD, HP-UX, and IRIX. This function takes an address, which could be a pointer to a static function within the module for example (if cast to void *), and fills in a Dl_info structure with information including the path name of the shared object containing that address (in the dli_fname member).
Unfortunately, there is no way to do that using UNIX or POSIX. If you need to use it to look up some sort of data, you should use the $PATH environment variable and search for the data in a path that is relative to each entry in $PATH. For example, it is not uncommon to store binaries in "installdir/bin" for some installation directory "installdir" and to store the associated data in "installdir/share/name_of_program" for some installation directory and some program named "name_of_program". If that is the case, then looking at "../share/name_of_program/name_of_resource_file" relative to each entry in getenv("PATH") is a good way of searching for resources. Another thing you could do is allow the necessary information to be provided on the commandline or in some configuration file, and only perform the search if needed as a fallback option.
Edit
Now that you've stated your rationale for this, I would advise you to simply use the QSettings class from Qt for your configuration information, as it uses the preferred native mechanism for each platform (the registry on Windows, a PLIST file on Mac OS X, the Gnome GConf database on Linux). You may want to take a look at my C++ Project Template as it uses Qt to do just this, and it provides simple commandline options to easily tweak the configuration settings ("--prefset", "--prefget", and "--preflist" manipulate QSettings).
That said, if you absolutely must use an XML configuration file of your own instead of using the preferred native mechanism, I strongly advise you to place the system-wide configuration in "installdir/etc" while placing your library in "installdir/lib" for some installation directory "installdir", as that is the typical place for configuration files on UNIX systems, and "installdir/lib" should ONLY be used for library files, not for configuration files and other errata. I suggest you place a user-specific version of the configuration file in "$XDG_CONFIG_HOME" (if it is defined) or in "$HOME/.config" (where "$HOME" is the user's home folder).
When searching for the system-wide configuration file, I would recommend that you search within $XDG_CONFIG_DIRS if it is defined; if it isn't defined, then falling back to "/etc/xdg" or searching for "../etc/name_of_your_program.conf.xml" relative to "$PATH" and possibly also relative to the "$LD_LIBRARY_PATH", "$DYLD_LIBRARY_PATH", "$DYLD_FALLBACK_LIBRARY_PATH"), the contents of "/etc/ld.so.conf" if it exists, and the contents of "/etc/ld.so.conf.d/*.conf" if those files exist, halting your search as soon as you encounter the first valid such configuration file would be a sensible approach.
Credit goes to Roger for pointing out the XDG Basedir Spec and for his excellent constructive criticisms.
Possible solutions:
You can read the /proc/{PID}/mmap file for the list of shared libraries. Where {PID} is the process pid (you can get it using getpid()).
Call the command line tool ldd for the program binary file (stored in argv[0]).
If you write a solution from scratch take a look of ldd commands source code from uClibc how to get the list of shared libs from an elf binary.