Perl subroutine calltips - with PythonScript

Michael Vincent · Nov 19, 2020, 11:05 PM

@PeterJones said in Perl subroutine calltips - with PythonScript:

If you have just cpan, I forget whether it handles prereqs

I believe it does - I normally just use CPAN and it fetches what I need to build.

Cheers.

Ekopalypse · Nov 19, 2020, 11:05 PM

I have cpan and it keeps installing stuff - did I choose to install the world??

Ekopalypse · Nov 19, 2020, 11:06 PM

it does this now since ~10 minutes

Ekopalypse · Nov 19, 2020, 11:08 PM

finished - but no Win32::API. started cpan Win32::API now.

Michael Vincent · Nov 19, 2020, 11:11 PM

@Ekopalypse
@PeterJones

Is there a reason you build your own Perl? I have Strawberry 5.24 installed and doing this works:

That’s @Ekopalypse script from above using my “system” Strawberry Perl 5.24 DLL (the Perl that has my Win32::Mechanize::NotepadPlusPlus and all my other stull installed on it). Not sure why it’s printing “9” in the PythonScript console - is that what it’s supposed to do? I thought I’d get that string "print something ...

Cheers.

Ekopalypse · Nov 19, 2020, 11:13 PM

@Michael-Vincent

I get also 9 and from the function it seems correct to return an int.
See my previous post. RunPerl returns only an int. Not sure how to get the result (the print output), so far.

Michael Vincent · Nov 19, 2020, 11:14 PM

@Ekopalypse said in Perl subroutine calltips - with PythonScript:

I get also 9

Oh, OK - great then. Seems I may be able to keep testing along without having to build a Perl and just use my Strawberry install.

Cheers.

Ekopalypse · Nov 19, 2020, 11:16 PM

@Michael-Vincent

My Win32::API has been built but not installed because of failing tests I guess. Can you try the "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();" and see what happens?

Michael Vincent · Nov 19, 2020, 11:19 PM

This post is deleted!

Michael Vincent · Nov 19, 2020, 11:24 PM

@Ekopalypse said in Perl subroutine calltips - with PythonScript:

Can you try

from ctypes import CDLL, POINTER, c_int, c_char_p

perllib = CDLL(r'C:\Strawberry\perl\bin\perl524.dll')

["-le", "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"]

perllib.RunPerl.restype = c_int
perllib.RunPerl.argtypes = c_int, POINTER(c_char_p), POINTER(c_char_p)
args = (c_char_p * 2)(b"-le", b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();")
print(perllib.RunPerl(len(args),args, None))

It just prints 9 in the PythonScript console. No new tab is opened. If I run the command itself from a prompt:

C:\ > perl -e "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"

I get a new tab in Notepad++ as expected.

At least if it printed 42 we’d know we’re on to something …

Cheers.

Ekopalypse · Nov 19, 2020, 11:25 PM

Ja, 42 would be nice :-)
So 9 seems to be an error code.

Ekopalypse · Nov 19, 2020, 11:34 PM

@Michael-Vincent

Can you try one more thing?
Replace the RunPerl call with this
print(perllib.RunPerl(len(args), args, (c_char_p * 1)(b'')))
With the newFile code, please.

Michael Vincent · Nov 20, 2020, 12:18 AM

@Ekopalypse

Same 9.

I tried both:

from ctypes import CDLL, POINTER, c_int, c_char_p

perllib = CDLL(r'C:\Strawberry\perl\bin\perl524.dll')

["-e", "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"]

perllib.RunPerl.restype = c_int
perllib.RunPerl.argtypes = c_int, POINTER(c_char_p), POINTER(c_char_p)
args = (c_char_p * 2)(b"-e", b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();")
print(perllib.RunPerl(len(args),args,(c_char_p * 1)(b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();")))

and

from ctypes import CDLL, POINTER, c_int, c_char_p

perllib = CDLL(r'C:\Strawberry\perl\bin\perl524.dll')

["-e", "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"]

perllib.RunPerl.restype = c_int
perllib.RunPerl.argtypes = c_int, POINTER(c_char_p), POINTER(c_char_p)
args = (c_char_p * 2)(b"-e", b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();")
print(perllib.RunPerl(len(args),args,(c_char_p * 1)(b'')))

HOWEVER … this:

from ctypes import CDLL, POINTER, c_int, c_char_p

perllib = CDLL(r'C:\Strawberry\perl\bin\perl524.dll')

["use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"]

perllib.RunPerl.restype = c_int
perllib.RunPerl.argtypes = c_int, POINTER(c_char_p), POINTER(c_char_p)
args = (c_char_p * 1)(b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();")
print(perllib.RunPerl(len(args),args,None))

produces 0 in the PythonScript console.

Cheers.

Ekopalypse · Nov 20, 2020, 1:50 PM

Ok, I should have installed strawberry perl in first place, solved all my issues.

First success

from ctypes import CDLL, POINTER, c_int, c_char_p

perllib = CDLL(r'D:\strawberry\perl\bin\perl532.dll')

perllib.RunPerl.restype = c_int
perllib.RunPerl.argtypes = c_int, POINTER(c_char_p), POINTER(c_char_p)

__args = [b"",
          b"-le",
          b"use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();"]
          
args = (c_char_p * len(__args))(*__args)
x = perllib.RunPerl(len(args), args, None)
print(x)

This works, but only one time. A second call results in a
OSError: exception: access violation writing 0x0000000000000024

Seems some cleanup needs to be done afterwards.

Michael Vincent · Nov 20, 2020, 2:29 PM

@Ekopalypse said in Perl subroutine calltips - with PythonScript:

Seems some cleanup needs to be done afterwards.

Yes, in my late night Google-ing I saw lots of references to free(args) after the RunPerl() call.

Examples:
https://comp.lang.perl.misc.narkive.com/r7M6eENL/dll-unload-question-for-embedded-perl-on-windows
https://www.nntp.perl.org/group/perl.wxperl.users/2017/01/msg9715.html

Cheers.

PeterJones · Nov 20, 2020, 2:36 PM

@Ekopalypse said in Perl subroutine calltips - with PythonScript:

__args = [b"", …

Weird. If I don’t have the empty zeroth argument, the call fails (x==9). I wonder why it needs the blank argument…

Michael Vincent · Nov 20, 2020, 2:42 PM

@PeterJones said in Perl subroutine calltips - with PythonScript:

I wonder why it needs the blank argument…

I read some stuff on Par::Packer and it seems the first argument may be the optional path to the perl executable.

https://oliverbetz.de/pages/Artikel/Portable-Perl-Applications

Cheers.

Ekopalypse · Nov 20, 2020, 4:57 PM

Hmm … it looks like freeing the interpreter is the issue.
I tried to replicate what RunPerl is doing and when I use this

from ctypes import CDLL, POINTER, c_int, c_char_p, c_void_p, byref

perllib = CDLL(r'D:\strawberry\perl\bin\perl532.dll')

# perllib.RunPerl.restype = c_int
# perllib.RunPerl.argtypes = [c_int, POINTER(c_char_p), POINTER(c_char_p)]

# Perl_sys_init3(int* argc, char*** argv, char*** env)
perllib.Perl_sys_init3.argtypes = [POINTER(c_int), POINTER(POINTER(c_char_p)), POINTER(POINTER(c_char_p))]

# PerlInterpreter * perl_alloc(void)
perllib.perl_alloc.restype = c_void_p
perllib.perl_alloc.argtypes = []

# void perl_construct(pTHXx)
perllib.perl_construct.argtypes = [c_void_p]

# int perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)  # only 4 params ??
perllib.perl_parse.restype = c_int
perllib.perl_parse.argtypes = [c_void_p, c_void_p, c_int, POINTER(c_char_p), POINTER(c_char_p)]  # we need 5 params according to RunPerl

# int perl_run(pTHXx)
perllib.perl_run.restype = c_int
perllib.perl_run.argtypes = [c_void_p]

__args = [b"", b"D:\\scripts\\perl\\1.pl" ]
# ********************************  content of 1.pl  ********************************
# use strict;
# use warnings;

# my $timestamp = localtime(time);

# sub logit {
	# my $message = shift;
	# my $filename = 'D:/report.txt';
	# open(my $fh, '>>', $filename) or die "Could not open file '$filename' $!";
	# print $fh $timestamp, " $message\n";
	# close $fh;
# }

# logit("test");
# **********************************************************************************


args = (c_char_p * len(__args))(*__args)

perllib.Perl_sys_init3(byref(c_int(len(args))), None, None)
my_perl = perllib.perl_alloc()
perllib.perl_construct(my_perl)
result = perllib.perl_parse(my_perl, None, len(args), args, None)
print('perl_parse', result)
result = perllib.perl_run(my_perl)
print('perl_run', result)
print(open(r'D:\report.txt', 'r').read())

I can run 1.pl multiple times

Ekopalypse · Nov 20, 2020, 10:19 PM

I guess I have a working “embedded” perl instance.


from ctypes import CDLL, POINTER, c_int, c_char_p, c_void_p, byref

perllib = CDLL(r'D:\strawberry\perl\bin\perl532.dll')

# Perl_sys_init3(int* argc, char*** argv, char*** env)
perllib.Perl_sys_init3.argtypes = [POINTER(c_int), POINTER(POINTER(c_char_p)), POINTER(POINTER(c_char_p))]

# PerlInterpreter * perl_alloc(void)
perllib.perl_alloc.restype = c_void_p
perllib.perl_alloc.argtypes = []

# void perl_construct(pTHXx)
perllib.perl_construct.argtypes = [c_void_p]

# int perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)  # only 4 params ??
perllib.perl_parse.restype = c_int
perllib.perl_parse.argtypes = [c_void_p, c_void_p, c_int, POINTER(c_char_p), POINTER(c_char_p)]  # we need 5 params according to RunPerl

# int perl_run(pTHXx)
perllib.perl_run.restype = c_int
perllib.perl_run.argtypes = [c_void_p]

# int perl_destruct(pTHXx)
perllib.perl_destruct.restype = c_int
perllib.perl_destruct.argtypes = [c_void_p]

# SV* Perl_eval_pv(pTHX_ const char *p, I32 croak_on_error)
perllib.Perl_eval_pv.restype = c_void_p
perllib.Perl_eval_pv.argtypes = [c_void_p, c_char_p, c_int]

# # SV * Perl_sv_pv(pTHX_ const IV i)
perllib.Perl_sv_pv.restype = c_char_p
perllib.Perl_sv_pv.argtypes = [c_void_p, c_void_p]


__args = [b"", b"-e", b"0"]  # test_npp
args = (c_char_p * len(__args))(*__args)

perllib.Perl_sys_init3(byref(c_int(len(args))), None, None)
my_perl = perllib.perl_alloc()
perllib.perl_construct(my_perl)
if perllib.perl_parse(my_perl, None, len(args), args, None) == 0:
    for perlcode in [b"reverse 'rekcaH lreP rehtonA tsuJ'", b"$a = 3; $a **= 2", b"$a = 3; $a **= "]:
        val = perllib.Perl_eval_pv(my_perl, c_char_p(perlcode), 0)
        print(perllib.Perl_sv_pv(my_perl, val))
else:
    print('Perl interpreter setup error.')

print(perllib.perl_destruct(my_perl))

Next step would be to identify errors (see last example code)
and make additional modules working. I assume this has something
to do with the @INC …
and of course make a class out of it for easy reuse.

Ekopalypse · Nov 23, 2020, 1:22 AM

I guess I have a working solution.
I’m afraid, it works, currently, only with PythonScript version 3.x
There is one open point, see TODO, which I can’t seem to find a solution for.

from ctypes import CDLL, POINTER, c_int, c_char_p, c_void_p, byref, CFUNCTYPE
from Npp import console

perllib = CDLL(r'D:\strawberry\perl\bin\perl532.dll')

# Perl_sys_init3(int* argc, char*** argv, char*** env)
Perl_sys_init3 = perllib.Perl_sys_init3
Perl_sys_init3.argtypes = [POINTER(c_int), POINTER(POINTER(c_char_p)), POINTER(POINTER(c_char_p))]

# PerlInterpreter * perl_alloc(void)
perl_alloc = perllib.perl_alloc
perl_alloc.restype = c_void_p
perl_alloc.argtypes = []

# void perl_construct(pTHXx)
perl_construct = perllib.perl_construct
perl_construct.argtypes = [c_void_p]

# int perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)  # only 4 params but pTHXx_ is a macro resulting in 5 params
xsinit = CFUNCTYPE(None, c_void_p)
perl_parse = perllib.perl_parse
perl_parse.restype = c_int
perl_parse.argtypes = [c_void_p, xsinit, c_int, POINTER(c_char_p), POINTER(c_char_p)]

# int perl_run(pTHXx)
perl_run = perllib.perl_run
perl_run.restype = c_int
perl_run.argtypes = [c_void_p]

# int perl_destruct(pTHXx)
perl_destruct = perllib.perl_destruct
perl_destruct.restype = c_int
perl_destruct.argtypes = [c_void_p]

# SV* Perl_eval_pv(pTHX_ const char *p, I32 croak_on_error)
Perl_eval_pv = perllib.Perl_eval_pv
Perl_eval_pv.restype = c_void_p
Perl_eval_pv.argtypes = [c_void_p, c_char_p, c_int]

# SV * Perl_sv_pv(pTHX_ const IV i)
Perl_sv_pv = perllib.Perl_sv_pv
Perl_sv_pv.restype = c_char_p
Perl_sv_pv.argtypes = [c_void_p, c_void_p]

# SV * Perl_sv_string_from_errnum(pTHX_ int errnum, SV *tgtsv)
Perl_sv_string_from_errnum = perllib.Perl_sv_string_from_errnum
Perl_sv_string_from_errnum.restype = c_void_p
Perl_sv_string_from_errnum.argtypes = [c_void_p, c_int, c_void_p]

# SV* Perl_get_sv(pTHX_ const char *name, I32 flags)
Perl_get_sv = perllib.Perl_get_sv
Perl_get_sv.restype = c_void_p
Perl_get_sv.argtypes = [c_void_p, c_char_p, c_int]

# void boot_DynaLoader (pTHX_ CV* cv)
boot_DynaLoader = perllib.boot_DynaLoader
boot_DynaLoader.argtypes = [c_void_p, c_char_p]

# Perl_newXS(pTHX_ const char *name, XSUBADDR_t subaddr, const char *filename)
Perl_newXS = perllib.Perl_newXS
Perl_newXS.argtypes = [c_void_p, c_char_p, c_void_p, c_char_p]


class PerlInterpreter:

    def __init__(self):
        Perl_sys_init3(byref(c_int(3)), None, None)


    @staticmethod
    def call(perlcode):
        # TODO: https://perldoc.perl.org/perlembed#Maintaining-a-persistent-interpreter
        # PL_exit_flags |= 0x2  # PERL_EXIT_DESTRUCT_END 
        # I assume, that this would avoid calling alloc, construct and parse over and over again.
        # but how can we set it, seems not to be exported.
        # Following code fails: ValueError: symbol 'PL_exit_flags' not found

        # exit_flags = c_int.in_dll(perllib, 'PL_exit_flags')
        # exit_flags.value |= 2
        
        my_perl = perl_alloc()
        perl_construct(my_perl)
        
        def xs_init(pTHX):
            # https://perldoc.perl.org/perlembed#Using-Perl-modules,-which-themselves-use-C-libraries,-from-your-C-program
            Perl_newXS(pTHX, 
                       b"DynaLoader::boot_DynaLoader", 
                       boot_DynaLoader, 
                       b'__FILE__' # Seems to work, but ... ??
                       )

        res = perl_parse(my_perl, xsinit(xs_init), 3, (c_char_p * 3)(*[b"", b"-e", b"0"]), None)
        if res != 0:
            _error = Perl_sv_pv(my_perl, 
                                Perl_sv_string_from_errnum(my_perl, res, None))

            perl_destruct(my_perl)
            raise(RuntimeError(f'Perl interpreter setup error. {_error.decode()}'))

        result = Perl_sv_pv(my_perl, 
                            Perl_eval_pv(my_perl, c_char_p(perlcode.encode()), 0))
        
        error = Perl_sv_pv(my_perl, Perl_get_sv(my_perl, "@".encode(), 0)).decode()

        perl_destruct(my_perl)
        return error, result.decode()


if __name__ == '__main__':
    perl = PerlInterpreter()
    for perlcode in [
                     "use Win32::Mechanize::NotepadPlusPlus qw/:main/; notepad->newFile();",
                     "reverse 'rekcaH lreP rehtonA tsuJ'", 
                     "$a = 3; $a **= 2",
                     "$a = 3; $a **= ",
                     ]:
        error, result = perl.call(perlcode)
        if error:
            console.writeError(error+'\n')
        else:
            print(result)