Perl subroutine calltips - with PythonScript

PeterJones

The other thing I realized: you probably won’t have all the prerequisite modules installed. I normally use the cpanm utility, which distributes with strawberry perl, and that automatically downloads and installs prereqs before the module you’re trying to install. Without such a tool (and if you built your own perl, which I think you did to get the DLL), I don’t know that you have that.

I think the make process will tell you what prereqs you’re missing … but it’s been a long time since I’ve done a complicated manual install of a module.

Oh, yep, there, you posted the error while I was typing. You’re going to have to install at least Win32::API first… doing that manually is a pain.

When you built your own perl, did you at least get cpan, if not cpanm? I think one or both would be in the same directory as perl.exe… if you have cpanm, just do cpanm Win32::Mechanize::NotepadPlusPlus, and everything should work. If you have just cpan, I forget whether it handles prereqs; try cpan Win32::Mechanize::NotepadPlusPlus; if that’s not sufficient, do the missing prereqs one at a time with the cpan client. If you have neither… um… That’s going to be tough.

Michael Vincent

@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

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

Ekopalypse

it does this now since ~10 minutes

Ekopalypse

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

Michael Vincent

@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

@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

@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

@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

This post is deleted!

Michael Vincent

@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

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

Ekopalypse

@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

@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

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

@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

@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

@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

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

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.