BBC: Blead Breaks File::AptFetch, Logfile::Read, others

[cjg-cguevara]

This is a bug report for perl from "Carlos Guevara" carlos@carlosguevara.com,
generated with the help of perlbug 1.42 running under perl 5.37.4.

---

[Please describe your issue here]

BBC: Blead Breaks File::Replace

Please see http://matrix.cpantesters.org/?dist=File::Replace

[Please do not change anything below this line]

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Flags:
category=core
severity=low

Site configuration information for perl 5.37.4:

Configured by cpan at Wed Aug 31 13:05:00 EDT 2022.

Summary of my perl5 (revision 5 version 37 subversion 4) configuration:
Commit id: e4bbbfe
Platform:
osname=openbsd
osvers=7.1
archname=OpenBSD.amd64-openbsd-thread-multi
uname='openbsd cjg-openbsd7 7.1 generic#3 amd64 '
config_args='-des -Dprefix=/bin/perl-blead -Dscriptdir=/bin/perl-blead/bin -Dusedevel -Duse64bitall -Duseithreads'
hint=recommended
useposix=true
d_sigaction=define
useithreads=define
usemultiplicity=define
use64bitint=define
use64bitall=define
uselongdouble=undef
usemymalloc=n
default_inc_excludes_dot=define
Compiler:
cc='cc'
ccflags ='-pthread -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include'
optimize='-O2'
cppflags='-pthread -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include'
ccversion=''
gccversion='OpenBSD Clang 13.0.0'
gccosandvers=''
intsize=4
longsize=8
ptrsize=8
doublesize=8
byteorder=12345678
doublekind=3
d_longlong=define
longlongsize=8
d_longdbl=define
longdblsize=16
longdblkind=3
ivtype='long'
ivsize=8
nvtype='double'
nvsize=8
Off_t='off_t'
lseeksize=8
alignbytes=8
prototype=define
Linker and Libraries:
ld='cc'
ldflags ='-pthread -Wl,-E -fstack-protector-strong -L/usr/local/lib'
libpth=/usr/lib/clang/13.0.0/lib /usr/lib /usr/local/lib
libs=-lpthread -lm -lutil -lc
perllibs=-lpthread -lm -lutil -lc
libc=/usr/lib/libc.so.96.1
so=so
useshrplib=false
libperl=libperl.a
gnulibc_version=''
Dynamic Linking:
dlsrc=dl_dlopen.xs
dlext=so
d_dlsymun=undef
ccdlflags=' '
cccdlflags='-DPIC -fPIC '
lddlflags='-shared -fPIC -L/usr/local/lib -fstack-protector-strong'

---

@inc for perl 5.37.4:
/home/cpan/bin/perl-blead/lib/site_perl/5.37.4/OpenBSD.amd64-openbsd-thread-multi
/home/cpan/bin/perl-blead/lib/site_perl/5.37.4
/home/cpan/bin/perl-blead/lib/5.37.4/OpenBSD.amd64-openbsd-thread-multi
/home/cpan/bin/perl-blead/lib/5.37.4

---

Environment for perl 5.37.4:
HOME=/home/cpan
LANG (unset)
LANGUAGE (unset)
LC_ALL=C
LD_LIBRARY_PATH (unset)
LOGDIR (unset)
PATH=/home/cpan/bin/perl-blead/bin:/home/cpan/bin:/home/cpan/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/X11R6/bin:/usr/local/bin:/usr/local/sbin:/usr/games
PERL_BADLANG (unset)
SHELL=/usr/local/bin/bash

[jkeenan]

Bisection points to 80c1f1e.

80c1f1e45e8ef8c27d170fae7ade41971fe20218 is the first bad commit
commit 80c1f1e45e8ef8c27d170fae7ade41971fe20218
Author: Tony Cook <tony@develop-help.com>
Date:   Tue Aug 16 15:52:04 2022 +1000
Commit:     Tony Cook <tony@develop-help.com>
CommitDate: Wed Aug 31 10:51:09 2022 +1000

    only clear the stream error state in readline() for glob()
...

@tonycoz, can you take a look?

[jkeenan]

Also affected by this commit: Log::Log4perl (as originally reported in #20208).

[bram-perl]

Reducing t/50_inplace.t of File::Replace to a minimal test case:

#!/usr/bin/perl -l

use strict;
use warnings;

use POSIX qw/dup dup2/;


sub s1 {
    print "\teof() is " . (eof() ? "true" : "false");
    while (<>) {
        chomp;
        print "\t<>: $ARGV: $.: $_";
    }
}

print "First call";
{
    open my $fh, "<", "foobar1" or die "Failed to open foobar1: $!";
    my $saved_fd = dup(0);
    dup2(fileno $fh, 0) or die "dup2 failed: $!";

    s1();

    dup2( $saved_fd, 0 ) or die "restore dup2: $!";
    POSIX::close( $saved_fd) or die "close saved: $!";
}

print "Second call";
{
    open my $fh, "<", "foobar2" or die "Failed to open foobar2: $!";
    my $saved_fd = dup(0);
    dup2(fileno $fh, 0) or die "dup2 failed: $!";

    s1();

    dup2( $saved_fd, 0 ) or die "restore dup2: $!";
    POSIX::close( $saved_fd) or die "close saved: $!";
}

Before running create the necessary files:

$ echo "BBBB: foobar :BBBB" > foobar2
$ echo "AAAA: foobar :AAAA" > foobar1

Running with 80c1f1e:

$ ./perl -Ilib gh-20207.pl
First call
        eof() is false
        <>: -: 1: AAAA: foobar :AAAA
Second call
        eof() is true

Running with 80c1f1e~1:

$ ./perl -Ilib gh-20207.pl
First call
        eof() is false
        <>: -: 1: AAAA: foobar :AAAA
Second call
        eof() is false
        <>: -: 1: BBBB: foobar :BBBB

With the old code 'eof' of STDIN was cleared,
with the new code it no longer is.

[tonycoz]

Reducing t/50_inplace.t of File::Replace to a minimal test case:

I see what's happening, but I think it's case of the test depending on the now fixed bug.

We read to end of file on *STDIN and the eof flag is set on PerlIO_stdin(), the underlying fd is modified to point at another file which isn't at end of file. With the old code clearerr() is called once we get to eof() (the bug) which also clears eof, but with the fix that no longer happens.

We could modify readline() to clear eof() rather than calling clearerr() (which clears both error and eof state), but I don't think it would be correct behaviour.

[andk]

Also affected: WHYNOT/File-AptFetch-v0.1.14.tar.gz
Sample report: http://www.cpantesters.org/cpan/report/caa6bb86-3b0e-11ed-a22f-a51cc21cab27

[tonycoz]

Also affected: WHYNOT/File-AptFetch-v0.1.14.tar.gz

Patch attached to ticket at https://rt.cpan.org/Ticket/Display.html?id=144442

[andk]

Also affected:

• JANPAZ/Logfile-Read-0.6.tar.gz http://www.cpantesters.org/cpan/report/8ef83580-3f21-11ed-8a39-7b29e48453bc
• TOBEYA/Nagios-Cmd-0.05.tar.gz http://www.cpantesters.org/cpan/report/ded30156-3ec3-11ed-84dd-5990dd8453bc

[andk]

Also affected: BOOK/Log-Procmail-0.12.tar.gz http://www.cpantesters.org/cpan/report/ef21d450-40c2-11ed-b3c4-fccdf10bed05

[tonycoz]

Logfile::Read patch at https://rt.cpan.org/Ticket/Display.html?id=144592