I'm reading about ELF file format and trying to create one without any library, to really understand how the things works. In fact, I was able to create one by setting all needed headers and put some op code to it print a string on std out. But how to create the string table and then the sections, to be honest, I have no code to show because I didn't understand even how to create the string table myself and set it to sh_name. I'd love any code example how to do this. I've search a lot on internet without luck. Even libelf doesn't show how to do it directly the explanation actually I get it's same as from standard elf document. I've tagged C and C++ but if you know how to do this in any other language please feel free to answer.
Related
as you can see the title explains a little.
I know several questions have alreay been asked about custom extensions, but i want also the file i'm using to be readable only from the program i'm writing, and if opened from the explorer,it would not be making any sense(maybe crypted).
The program i'm coding is a substitution cipher
in C++, and it works with two maps, so that every letter in the message would be found in one map, and substituted with the corresponding letter in the other.
I'm trying to store these 2 maps in a file, so how would you suggest i could acheive this ?
P.S: I couldn't find any similar question, If you do, please give me a link
Basically, I want to be to be able to pass data between Excel cells and
my C++ program. I don't have any experience in Excel/C++ interactions and I haven't been able to find a coherent explanation or documentation on any websites. If someone could link me some references or provide one themselves it would be much appreciated. Thanks.
If this is for a Windows system, you could always use one of the available managed Excel libraries, such as OfficeWriter or Aspose.
There also might be similar libraries specifically for c++, I know we (OfficeWriter) used to make one.
Edit: Looks like there are a few out there, like LibXL and BasicExcel.
If the application will run on an end user machine with Excel installed, you can easily use the Excel interop and keep Excel hidden.
In addition to LibXL and BasicExcel mentioned by smoore, there is:
ExcelFormat Library is an improved version of the BasicExcel library and will allow you to read and write simple values. It is free.
xlslib will also read and write simple values, I have not tried it tho. It is also free.
Number Duck, is a commercial library that I have written, It supports reading and writing values, formulas and pictures. The website has examples of how to use the features.
Are there any C/C++ libraries available that can be used in creating, loading and saving files in .odt-format?
Alternatively, where can I find tutorial-like information on implementing .odt(/ODF) specifications?
This site: OASIS OpenDocument Essentials seems to cover the problem, including howto-examples and shortcuts.It's quite nicely done and easy to follow.
Flexibility can be perceived as complexity. If you don't need the
flexibility, create a template ODT and just fill in the content as
needed. As mentioned, there exist XML parsers to actually handle IO.
ODT isn't a plaintext file, so some complexity/difficulty is expected.
– Ioan
From the link:
The Virtues of Cheating
As you begin to work with OpenDocument files, you may want to write a
program that constructs a document with some feature that isn’t
explained in this book—this is, after all, an “essentials” book. Just
start OpenOffice.org or KOffice, create a document that has the
feature you want, unpack the file, and look for the XML that
implements it. To get a better understanding of how things works,
change the XML, repack the document, and reload it. Once you know how
a feature works, don’t hesitate to copy and paste the XML from the
OpenDocument file into your program. In other words, cheat. It worked
for me when I was writing this book, and it can work for you too!
I am trying to develop a tool that inserts comments in C/C++ source files in pre-defined formats.
The comments could be:
file headers <-> file names required
class comments <-> class name required
function comments <-> function name required
Following points are required to be taken mind:
If the comments are already there in right format then leave them intact.
If the comments are broken them fix them and insert them.
Some desirable but non important features:
Check and fix the indentation.
Check if any breaks are missing in their respective cases.
Please suggest open-source / free libraries / logic to aid in this.
I guess you 've got two choices:
Generate the whole c/c++ code and headers from a template or scripting language and use this one to insert the preformated comments. This is of course not an option if you still got a lot of code.
Or you need a tool to parse the code into sth. you can further use. You could try doxygen to generate html, xml or some other format. Problem would still be, how to get the generated documentation back into your sources...
I was looking for a solution to store program settings or options or configuration in C++. These could be settings that are exposed in a GUI and need to be saved between runs of my code.
In my search I came across boost.PropertyTree which seemed to be a good choice. I know boost is well respected code so I'm comfortable using it and so I started developing using this. Then I come across boost.program_options which seems to allow you to do the same thing but also looks more specialized for the specific use-case of program settings.
Now I'm wondering which is the most appropriate for the job? (or is there a 3rd option that is better than both)
EDIT:
fyi this is for a plugin so it will not use command line options (as in, it's not even possible).
UPDATE
I ended up sticking with boost.PropertyTree. I needed to be able to save changed options back to the INI, and I didn't see a way of doing that with boost.program_options.
Use boost::program_options. It's exactly what it's for. In one library you get command line options, environment variables options and an INI-like configuration file parser. And they're all integrated together in the Right way, so when then the user specifies the same option in more than one of these sources the library knows the Right priority order to consider.
boost::property_tree on the other hand is a more generalized library. The library parses the text stream into a uniform data model. But You need to do the real parsing -- that of making sense of the blob of data for your needs. The library doesn't know when to expect a parameter when it sees a particular option string, or to disallow specific values or types of values for a particular option.
After some digging around I think boost.PropertyTree is still the best solution because it gives me the capability to save the options after changing them from within the program which is a requirement.
There is a non-Boost possibility too. Config4Cpp is a robust, simple-to-use and comprehensively documented configuration-file parser library that I wrote. It is available at www.config4star.org.
I suggest you read Chapter 3 (Preferences for a GUI Application) of the Practical Usage Guide manual to read an overview of how Config4Cpp can do what you want. Then open the Getting Started Guide manual, and skim-read Chapters 2 and 3, and Section 7.4 (you might prefer to read the PDF version of that manual). Doing that should give you sufficient details to help you decide if Config4Cpp suits your needs better or worse than Boost.
By the way, the indicated chapters and sections of documentation are short, so they shouldn't take long to read.