treewide: check alternates writes with eof + autodie

We must use eof() combined with close() to detect errors
in situations involving the readline()' op since `readline'
(and most buffered I/O libraries) have weak error detection
support.

This fixes error detection for files opened for read/write
access.  The next commit will fix error detection for read-only
files.

1 files changed, 15 insertions, 14 deletions

diff --git a/lib/PublicInbox/LeiToMail.pm b/lib/PublicInbox/LeiToMail.pm
index b07c2c90..e80163e2 100644
--- a/lib/PublicInbox/LeiToMail.pm
+++ b/lib/PublicInbox/LeiToMail.pm
@@ -12,6 +12,7 @@ use PublicInbox::Spawn qw(spawn);
 use IO::Handle; # ->autoflush
 use Fcntl qw(SEEK_SET SEEK_END O_CREAT O_EXCL O_WRONLY);
 use PublicInbox::Syscall qw(rename_noreplace);
+use autodie qw(open seek close);
 
 my %kw2char = ( # Maildir characters
         draft => 'D',
@@ -255,7 +256,7 @@ sub _buf2maildir ($$$$) {
                 $tmp = $dst.'tmp/'.$rand.$common;
         } while (!($ok = sysopen($fh, $tmp, O_CREAT|O_EXCL|O_WRONLY)) &&
                 $!{EEXIST} && ($rand = _rand.','));
-        if ($ok && print $fh $$buf and close($fh)) {
+        if ($ok && print $fh $$buf and $fh->close) {
                 $dst .= $dir; # 'new/' or 'cur/'
                 $rand = '';
                 do {
@@ -458,7 +459,7 @@ sub _pre_augment_maildir {
         require File::Path;
         File::Path::make_path(map { $dst.$_ } qw(tmp new cur));
         # for utime, so no opendir
-        open $self->{poke_dh}, '<', "${dst}cur" or die "open ${dst}cur: $!";
+        open $self->{poke_dh}, '<', "${dst}cur";
 }
 
 sub clobber_dst_prepare ($;$) {
@@ -538,11 +539,11 @@ sub _pre_augment_text {
                 $out = $lei->{$devfd};
         } else { # normal-looking path
                 if (-p $dst) {
-                        open $out, '>', $dst or die "open($dst): $!";
+                        open $out, '>', $dst;
                 } elsif (-f _ || !-e _) {
                         # text allows augment, HTML/Atom won't
                         my $mode = $lei->{opt}->{augment} ? '>>' : '>';
-                        open $out, $mode, $dst or die "open($mode, $dst): $!";
+                        open $out, $mode, $dst;
                 } else {
                         die "$dst is not a file or FIFO\n";
                 }
@@ -561,7 +562,7 @@ sub _pre_augment_mbox {
                 $out = $lei->{$devfd};
         } else { # normal-looking path
                 if (-p $dst) {
-                        open $out, '>', $dst or die "open($dst): $!";
+                        open $out, '>', $dst;
                 } elsif (-f _ || !-e _) {
                         require PublicInbox::MboxLock;
                         my $m = $lei->{opt}->{'lock'} //
@@ -574,7 +575,7 @@ sub _pre_augment_mbox {
                 $lei->{old_1} = $lei->{1}; # keep for spawning MUA
         }
         # Perl does SEEK_END even with O_APPEND :<
-        $self->{seekable} = seek($out, 0, SEEK_SET);
+        $self->{seekable} = $out->seek(0, SEEK_SET);
         if (!$self->{seekable} && !$!{ESPIPE} && !defined($devfd)) {
                 die "seek($dst): $!\n";
         }
@@ -616,7 +617,7 @@ sub _do_augment_mbox {
         if (my $zsfx = $self->{zsfx}) {
                 $rd = PublicInbox::MboxReader::zsfxcat($out, $zsfx, $lei);
         } else {
-                open($rd, '+>>&', $out) or die "dup: $!";
+                open($rd, '+>>&', $out);
         }
         my $dedupe;
         if ($opt->{augment}) {
@@ -636,7 +637,7 @@ sub _do_augment_mbox {
                 PublicInbox::MboxReader->$fmt($rd, \&_augment, $lei);
         }
         # maybe some systems don't honor O_APPEND, Perl does this:
-        seek($out, 0, SEEK_END) or die "seek $dst: $!";
+        seek($out, 0, SEEK_END);
         $dedupe->pause_dedupe if $dedupe;
 }
 
@@ -672,12 +673,12 @@ sub _pre_augment_v2 {
         $lei->{v2w} = $v2w;
         return if !$lei->{opt}->{shared};
         my $d = "$lei->{ale}->{git}->{git_dir}/objects";
-        my $al = "$dir/git/0.git/objects/info/alternates";
-        open my $fh, '+>>', $al or die "open($al): $!";
-        seek($fh, 0, SEEK_SET) or die "seek($al): $!";
-        grep(/\A\Q$d\E\n/, <$fh>) and return;
-        print $fh "$d\n" or die "print($al): $!";
-        close $fh or die "close($al): $!";
+        open my $fh, '+>>', my $f = "$dir/git/0.git/objects/info/alternates";
+        seek($fh, 0, SEEK_SET); # Perl did SEEK_END when it saw '>>'
+        my $seen = grep(/\A\Q$d\E\n/, <$fh>);
+        eof($fh) or die "not at `$f' EOF ($!)"; # $! was set by readline
+        print $fh "$d\n" if !$seen;
+        close $fh;
 }
 
 sub pre_augment { # fast (1 disk seek), runs in same process as post_augment