How to get ruby mkmf to recognize a patched in function? - c

I'm interested in using ruby-prof and specifically interested in the memory profiling aspect of it. I'm trying to use it for ruby 1.9.3-p484 specifically. I know it requires a patch, and have essentially applied this albeit modified for p484.
Ruby compiles/builds fine and my irb for the ruby environment has those functions defined on GC
irb(main):001:0> GC.malloc_allocations
=> 56769
irb(main):002:0> GC.malloc_allocated_size
=> 11939060
I then try to gem install ruby-prof (using the gem binary from my custom ruby) and it installs fine. However, the mkmf extconf it runs over refuses to recognize the patched in functions. Irb confirms this.
irb(main):004:0> have_func("rb_gc_malloc_allocations")
checking for rb_gc_malloc_allocations()... no
=> false
irb(main):005:0> have_func("rb_gc_malloc_allocated_size")
checking for rb_gc_malloc_allocated_size()... no
=> false
I know the documentation for have_func says it checks the "common" (not sure what that means) header files first or any other header files you tell it to check. ruby-prof by default just checks the common headers (in their extconf.rb).
Unfortunately, I'm not too hot with C. Am I missing something with the patch? Do I need to put something in the ruby headers too? Some flags I need to pass to the gem install command so ruby-prof's extconf.rb finds the right function? Any suggestions?

So, I've figured this out finally (with some help from coworkers of course). It turns out that the function did need to be exposed as available in the ruby headers. The patch I posted in the question needed to be tweaked a bit to match what ruby-prof was expecting (and to expose the function in the headers).
I've put it up here in the hopes that it'll help out some future knowledge seeker.

Related

Is there a way to get help for some C functions inside of vim/Neovim?

This question may be a little off topic. But I was wondering if there was a way for me to look at the descriptions of C functions using vim or neovim. Is it possible to look at their documentations by doing something like :help? This would really be helpful since I wouldn't need to lookup to my browser everytime.
I am unclear about these things:
Can :help be my friend here ?
Can I use LSPs to do something like this ?
I am using latest Neovim inside Ubunutu 20.04 in WSL. Is this helpful somehow ?
By pressing K, the keyword under the cursor is looked up using a configured keyword lookup program, the default being man. This works pretty much out of the box for the C standard library.
For C++, you might want to look at something like cppman.
Well yes, you can get the description of C functions by using a LSP (language server plugin)! Here is an image of me using clangd as my LSP:
You'd "just" need to install the LSP and start it. I don't know how familiar you're with neovim, but just in case if you don't know how to install a plugin or to be more specifique: If you don't know how you can install a LSP server, then you can do the following:
There're plenty videos how to set up a LSP-Server for your language. Here's an example.
If you don't want to set up on your own, you can pick up one of the preconfigured neovim setups (some of my friends are recommending lunarvim)
But yeah, that's it. If you have any further questions feel free to ask them in the comments.
Happy vimming c(^-^)c
Let's explain how "K" command works in more detail.
You can run external commands by prefixing them with :! command. So running man tool is as easy as
:!man <C-R><C-W>
Here <C-R><C-W> is a special key combination used to put word under cursor from text buffer down to command line.
Same for showing Vim's built-in help page
:help <C-R><C-W>
As it feels tedious to type that, Vim also defines K Normal mode command that does pretty much the same thing. Except the tool name is taken from value of an option named "keywordprg".
So doing set keywordprg=man (default for *nix systems) makes K to invoke !man tool; while set keywordprg=:help is for bultin help.
Also, the option :h 'keywordprg' is made global or local-to-buffer, so any Vim buffer is able to overwrite global setting. For example, this is already done by standard runtime for "vim" and "help" buffers, so they call ":help" instead of "man".
The problem with :!man command is that it shows "black console". It'd be nice if we could capture man's output and open it inside Vim just like a builtin help page. Then we could also apply some pretty highlighting, assign key macros and all such. This is a pretty common trick and it is already done by a standard plugin shipped with Vim/Neovim.
A command that the plugin provides is called :Man, so you can open :Man man instead of :!man man, for example. The plugin is preactivated in Neovim; for Vim you still need to source one file manually. So to make use of this plugin you'll need something like this
set keywordprg=:Man
if !has("nvim")
source $VIMRUNTIME/ftplugin/man.vim
endif
The previous answer recommending cppman is the way to go. There is no need to install a bulky language server just for the purpose of having the hover functionality. However, make sure you're caching the man pages via cppman -c. Otherwise, there will be a noticeable delay since cppman is fetching the page from cppreference.com on the fly.
If you like popups for displaying documentation, convert the uncompressed man pages (groff -t -e -mandoc -Tascii <man-page> | col -bx), and set keywordprg to your own wrapper to search for keywords according to your needs.

Can the meson project version be assigned dynamically?

I am new to Meson so please forgive me if this is a stupid question.
Simple Version of the Question:
I want to be able to assign a dynamic version number to the meson project version at build time. Essentially meson.project_version()=my_dynamic_var or project( 'my_cool_project', 'c', version : my_dynamic_var') (which of course won't work).
I would rather not pre-process the file if I don't have to.
Some background if anybody cares:
My build system dynamically comes up with a version number for the project. In my case, it is using a bash script. I have no problem getting that version into my top level meson.build file using run_command and scraping stdout from there. I have read that using doing it this way is bad form so if there is another way to do this.. I am all ears.
I am also able to create and pass the correct -DPRODUCT_VERSION="<my_dynamic_var>" via add_global_arguments so I COULD just settle for that.. but I would like the meson project itself to carry the same version for the logs and so I can use meson.project_version() to get the version in subprojects for languages other than c/c++.
The short answer, as noted in comments to the question, appears to be no. There is no direct way to set the version dynamically in the project call.
However, there are some work arounds, and the first looks promising for the simple case:
(1) use meson rewriting capability
$ meson rewrite kwargs set project / version 1.0.0
Then obviously use an environment variable instead of 1.0.0.
(2) write a wrapper script which reads the version from the environment and substitutes it into your meson.build file in the project call.
(3) adopt conan.io and have your meson files generated.
(4) use build options. This option, while not as good as (1) might work for other work flows.
Here's how option (4) works.
create a meson_options.txt file in your meson root directory
add the following line:
option('version', type : 'string', value : '0.0.0', description : 'project version')
then create a meson.build file that reads this option.
project('my_proj', 'cpp')
version = get_option('version')
message(version)
conf_data = configuration_data()
conf_data.set('version', version)
When you go to generate your project, you have an extra step of setting options.
$ meson build && cd build
$ meson configure -Dversion=$BUILD_VERSION
Now the version is available as a build option, then we use a configuration_data object to make it available for substitution into header/source files (which you might want to get it into shared libraries or what not).
configure_file(
input : 'config.hpp.in',
output : 'config.hpp',
configuration : conf_data
)
And config.hpp.in looks something like this:
#pragma once
#include <string>
const static std::string VERSION = "#version#";
When we do the configure_file call, #version# will get substituted for the version string we set in the meson configure step.
So this way is pretty convoluted, but like I said, you may still end up doing some of it, e.g. to print copyright info and what not.
As of 0.60.3 you may directly assign version from run_command which means the following will work without any meson_options.txt.
project('randomName', 'cpp',
version : run_command('git', 'rev-parse', '--short', 'HEAD').stdout().strip(),
default_options : [])
In particular, it is also possible to assign the result of a bash script, simply invoke it instead of git.

Shows Missing library : ff while building echidna using stack install

I am trying to build echidna using stack install.
https://github.com/crytic/echidna
I am continuously getting the missing library error while installing at a progress state of 171/178.
I believe it to be more of stack error than library error. Error shown is as follows
I have tried installing the library but not getting any C library of such sort.ye
SO, i've installed every library using
sudo apt-get install lib*ff*-dev
isn't working yet.
-- While building package hevm-0.31 using:
/home/aman/.stack/setup-exe-cache/x86_64-linux/Cabal-simple_mPHDZzAJ_2.2.0.1_ghc-8.4.3 --builddir=.stack-work/dist/x86_64-linux/Cabal-2.2.0.1 configure --with-ghc=/home/aman/.stack/programs/x86_64-linux/ghc-8.4.3/bin/ghc --with-ghc-pkg=/home/aman/.stack/programs/x86_64-linux/ghc-8.4.3/bin/ghc-pkg --user --package-db=clear --package-db=global --package-db=/home/aman/.stack/snapshots/x86_64-linux/lts-12.10/8.4.3/pkgdb --package-db=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/pkgdb --libdir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/lib --bindir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/bin --datadir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/share --libexecdir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/libexec --sysconfdir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/etc --docdir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/doc/hevm-0.31 --htmldir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/doc/hevm-0.31 --haddockdir=/home/aman/Desktop/new/echidna2/echidna/.stack-work/install/x86_64-linux/lts-12.10/8.4.3/doc/hevm-0.31 --dependency=QuickCheck=QuickCheck-2.11.3-3XHQpBYb83U2mMvNz2AjQX --dependency=abstract-par=abstract-par-0.3.3-Ie3MD7O3orK6ZR8i7FuBEv --dependency=aeson=aeson-1.3.1.1-7JlrwYHW7OR9ca4RRZ9oOf --dependency=ansi-wl-pprint=ansi-wl-pprint-0.6.8.2-9fh9v74MJQDJeSHE7X3Co6 --dependency=async=async-2.2.1-7DQr5PBcpiwJNOuf7ZiSPa --dependency=base=base-4.11.1.0 --dependency=base16-bytestring=base16-bytestring-0.1.1.6-I0igvRcEwRNBMqqPC2yQBh --dependency=base64-bytestring=base64-bytestring-1.0.0.1-4OCIe2BZn8jKI191JIXI37 --dependency=binary=binary-0.8.5.1 --dependency=brick=brick-0.37.2-HmDqAExuwtV4o98FRmS9eK --dependency=bytestring=bytestring-0.10.8.2 --dependency=cereal=cereal-0.5.7.0-ILaYAmVTyR1IcEsGXXUCfI --dependency=containers=containers-0.5.11.0 --dependency=cryptonite=cryptonite-0.25-GgyZs9E1viv2owjaLxA3vq --dependency=data-dword=data-dword-0.3.1.2-CMzWV6RCGtK8L6wsVSErKS --dependency=deepseq=deepseq-1.4.3.0 --dependency=directory=directory-1.3.1.5 --dependency=fgl=fgl-5.6.0.0-E3fRSNebqkULRqplV3ljSc --dependency=filepath=filepath-1.4.2 --dependency=ghci-pretty=ghci-pretty-0.0.2-I5PJbL8ge6MChp3KxZbHqH --dependency=haskeline=haskeline-0.7.4.3-5EI2v7Zmtnz57a7mmnEGOS --dependency=lens=lens-4.16.1-B0f4CyKKTUGAKBzzY965AX --dependency=lens-aeson=lens-aeson-1.0.2-Jly9eqrxMbj6GutGwOKn69 --dependency=megaparsec=megaparsec-6.5.0-G48ltiRFbVUHATB1lTnNRx --dependency=memory=memory-0.14.16-GTCi0eCrvrnI3inLDBWVMK --dependency=monad-par=monad-par-0.3.4.8-Jjk0JT5qYVK4xEO13GFUu8 --dependency=mtl=mtl-2.2.2 --dependency=multiset=multiset-0.3.4.1-DOPR5uXspss8vZY4jdOdOo --dependency=operational=operational-0.2.3.5-4jEcCWo4nKu1T4LZlKqe58 --dependency=optparse-generic=optparse-generic-1.3.0-1jcIewFKPXBLcRetZisV2l --dependency=process=process-1.6.3.0 --dependency=quickcheck-text=quickcheck-text-0.1.2.1-2lR7Kay7WBV5AMKAdKDpZZ --dependency=regex-tdfa=regex-tdfa-1.2.3.1-9PkkapJrmiKFVG38JA02jN --dependency=restless-git=restless-git-0.7-83nBoDMPYLtJIx01bvXzKs --dependency=rosezipper=rosezipper-0.2-GAlMD5j8Qb83GzjCYQknnx --dependency=s-cargot=s-cargot-0.1.4.0-J9AhWfrUxDQ6YMTyzXkHth --dependency=scientific=scientific-0.3.6.2-5di0UflhS5I1xpiiCPzjKz --dependency=semver-range=semver-range-0.2.7-dBvW3ofcsgDQf0zazTsJd --dependency=temporary=temporary-1.3-5Z6bOFbSCb7VhnH5UnI2r --dependency=text=text-1.2.3.0 --dependency=text-format=text-format-0.3.2-Fd261TSu6ptAAzilVN6BFx --dependency=time=time-1.8.0.2 --dependency=transformers=transformers-0.5.5.0 --dependency=tree-view=tree-view-0.5-Kkrk0dCM0oj2Q4xwPbd7Gg --dependency=unordered-containers=unordered-containers-0.2.9.0-IkfpzvG0LzrHAbTzfMidvY --dependency=vector=vector-0.12.0.1-4awQG9XUvVEBfJgKGHBhOb --dependency=vty=vty-5.21-A2OCwk39Wv3J3RjR3BvHey --dependency=witherable=witherable-0.2-2RYbFmOnVolGAqiDDS1CLe --dependency=wreq=wreq-0.5.2.1-IjuXB0jwsxA7O3uIVjcJXu --extra-include-dirs=/home/aman/Downloads/Compressed/ff13c/source/ --extra-include-dirs=/usr/local/opt/readline/include --extra-lib-dirs=/usr/local/opt/readline/lib
Process exited with code: ExitFailure 1
Logs have been written to: /home/aman/Desktop/new/echidna2/echidna/.stack-work/logs/hevm-0.31.log
Configuring hevm-0.31...
Cabal-simple_mPHDZzAJ_2.2.0.1_ghc-8.4.3: Missing dependency on a foreign
library:
* Missing (or bad) C library: ff
This problem can usually be solved by installing the system package that
provides this library (you may need the "-dev" version). If the library is
already installed but in a non-standard location then you can use the flags
--extra-include-dirs= and --extra-lib-dirs= to specify where it is.If the
library file does exist, it may contain errors that are caught by the C
compiler at the preprocessing stage. In this case you can re-run configure
with the verbosity flag -v3 to see the error messages.
The stack install must find this library and end up successfully installing the library I'm using.
So, it is clear from the error provided above, that the installation was not able to find the libff file.
The best solution is to build the libff library manually and copy the required builds at the place it should be.
The best way to debug the problem is to look at the executed command closely and try to find the possible places where the libff should be...
Looking into the very 2nd error line, i.e. the complete command it was trying to execute
here, I sighted the following options being executed
--extra-include-dirs=/usr/local/opt/readline/include --extra-lib-dirs=/usr/local/opt/readline/lib
In order to solve this, I looked for the required libff library and cloned it from GitHub. I cloned the required dependencies and places them in the directory it should be.
https://github.com/scipr-lab/libff
I then followed the "Build guide" to build the required library.
Then with the superuser on, I created the directories, /usr/local/opt/readline/lib and /usr/local/opt/readline/include, and it was solved. And pasted the required builds in it.
Used stack install again, and it worked.
Note:
I thought many beginners may have similar problem while installing the required tools for their use. These small ideas may help them.

Biometric matching with futronic sdk using nodejs server

I have successfully taken bio-metric prints and posted to the node server using the futronic sdk. I want to be able to use this library likewise for matching in the server because that's where the bio-metric prints for all users are stored. I stubbled upon the node-ffi library that helps define equivalent C functions that I have exported and compiled it down to a .dll file.
Now the challenge here is that I have tried to port the ftrAnsiSDK functions but the ftrScanAPI.dll and the ftrAnsiSDK.dll file could not be compiled together. It gives this error:
...collect2.exe [Error] ld returned 5 exit status
When I compile and export the functions that are not dependent on these two libraries, my code works fine and the functions are easily exported and used in the node server. Please can any one give me a hint?
Here is the link to the repo. It consists of the lib and .dll library that is been used.
For the server code here is a snippet of what I am trying to achieve:
var libm = ffi.Library('lib/visystem', {
'HelloWorld': [ 'void', [] ],
'PrintErrorMessage': [ 'void', ['int'] ],
'CaprureImage': [ 'int', ['int','int','int'] ]});
The HelloWord and PrintErrorMessages are methods that I used as a test case to ensure the functions are being exported before I proceeded to the main functions (you can see the function definition in from the code in the repo.. ) that depends on the futronic lin and sdk.
I am currently using a 64-bit operation system and I installed the same program on a 32-bit machine to be sure, but it still did not compile and export the function. The code editor I am using is Dev++C.
Can anyone help or even give me hint on how to achieve this goal?
As a disclaimer, I'm not familiar with the Dev-C++ IDE or MinGW development.
However, after a cursory look at your github repo, according to your libvisystem.def file, it appears that the only functions that are exported by your DLL are:
HelloWorld
PrintErrorMessage
ReadTemplateFile
SaveBmpFile
SaveTemplateFile
This is also confirmed when looking at the libvisystem.a library header:
So you should probably start by manually add the rest of the exported functions in your dll.h to the def file, in a similar manner to the ones that are already there, and see if that changes anything.
NOTE:
I'm not sure whether the __declspec(dllexport) directive is ignored by the Dev-C++ compiler/linker and it uses the def file instead. Perhaps others on SO have an idea.

Portable access to sysconfdir via config.h

I'd like my application to have portable access to the configuration files installed during make install (dist_sysconf_DATA). Is it possible to access $(sysconfdir) via config.h?
It is, but you should not do this according to official voices (as in, I am not gonna search the manual for it now) so as to continue supporting overriding it for specific objects to be built.
make CPPFLAGS="-USYSCONFDIR -DSYSCONFDIR=/blah" thisoneobject.o
Hence, what one is supposed to do:
AM_CPPFLAGS = -DSYSCONFDIR=\"${sysconfdir}\"
If you're using autoheader, adding this to your configure.ac will output a SYSCONFDIR macro in your config.h, and it will be defined with the value $(sysconfdir) or ${prefix}/etc.
if test "x$sysconfdir" = 'x${prefix}/etc'; then
if test "x$prefix" = 'xNONE'; then
sysconfdir=$ac_default_prefix/etc
else
sysconfdir=$prefix/etc
fi
fi
AC_DEFINE_UNQUOTED([SYSCONFDIR], ["$sysconfdir"], [location of system configuration directory])
But I would strongly recommend against doing that, and instead, stick with using the -DSYSCONFDIR flag. It's less code and therefore less prone to something going wrong. Using a condition in configure.ac such I mentioned may not be portable or take into account every case that might be encountered. Using -DSYSCONFDIR is the best option. Sometimes appearance just doesn't matter.
What I believe is most commonly done (and this is what I do)
Add the following in your Makefile.am
AM_CPPFLAGS = -DSYSCONFIR='"$(sysconfdir)"'
And now you can access SYSCONFDIR in source

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