use read_all in more places to improve safety

`readline' ops may not detect errors on partial reads.
This saves us some code to reduce cognitive overhead for
readers.  We'll also support reusing a destination buffers so it
can work more nicely with existing code.

13 files changed, 37 insertions, 42 deletions

diff --git a/lib/PublicInbox/Gcf2.pm b/lib/PublicInbox/Gcf2.pm
index 37262e28..4f163cde 100644
--- a/lib/PublicInbox/Gcf2.pm
+++ b/lib/PublicInbox/Gcf2.pm
@@ -9,7 +9,7 @@ use PublicInbox::Spawn qw(which popen_rd); # may set PERL_INLINE_DIRECTORY
 use Fcntl qw(SEEK_SET);
 use Time::HiRes qw(clock_gettime CLOCK_MONOTONIC);
 use IO::Handle; # autoflush
-use PublicInbox::Git;
+use PublicInbox::Git qw(read_all);
 use PublicInbox::Lock;
 
 BEGIN {
@@ -43,12 +43,11 @@ BEGIN {
                 # build them.
                 my $f = "$dir/gcf2_libgit2.h";
                 open my $src, '<', $f;
-                local $/;
-                $c_src = <$src> // die "read $f: $!";
+                $c_src = read_all($src);
         }
         unless ($c_src) {
                 seek($err, 0, SEEK_SET);
-                $err = do { local $/; <$err> };
+                $err = read_all($err);
                 die "E: libgit2 not installed: $err\n";
         }
         # append pkg-config results to the source to ensure Inline::C
diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index 35bd10ef..a460d155 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -550,11 +550,12 @@ sub modified ($;$) {
 
 # read_all/try_cat can probably be moved somewhere else...
 
-sub read_all ($;$) {
-        my ($fh, $len) = @_;
-        my $r = read($fh, my $buf, $len //= -s $fh);
+sub read_all ($;$$) {
+        my ($fh, $len, $bref) = @_;
+        $bref //= \(my $buf);
+        my $r = read($fh, $$bref, $len //= -s $fh);
         croak("$fh read ($r != $len)") if $len != $r;
-        $buf;
+        $$bref;
 }
 
 sub try_cat {
diff --git a/lib/PublicInbox/InboxWritable.pm b/lib/PublicInbox/InboxWritable.pm
index 65952aa2..6af72e71 100644
--- a/lib/PublicInbox/InboxWritable.pm
+++ b/lib/PublicInbox/InboxWritable.pm
@@ -7,6 +7,7 @@ use strict;
 use v5.10.1;
 use parent qw(PublicInbox::Inbox PublicInbox::Umask Exporter);
 use PublicInbox::Import;
+use PublicInbox::Git qw(read_all);
 use PublicInbox::Filter::Base qw(REJECT);
 use Errno qw(ENOENT);
 our @EXPORT_OK = qw(eml_from_path);
@@ -114,9 +115,8 @@ sub filter {
 sub eml_from_path ($) {
         my ($path) = @_;
         if (sysopen(my $fh, $path, O_RDONLY|O_NONBLOCK)) {
-                return unless -f $fh; # no FIFOs or directories
-                my $str = do { local $/; <$fh> } or return;
-                PublicInbox::Eml->new(\$str);
+                return unless -f $fh && -s _; # no FIFOs or directories
+                PublicInbox::Eml->new(\(my $str = read_all($fh, -s _)));
         } else { # ENOENT is common with Maildir
                 warn "failed to open $path: $!\n" if $! != ENOENT;
                 undef;
diff --git a/lib/PublicInbox/LeiALE.pm b/lib/PublicInbox/LeiALE.pm
index cc9a2095..b198af1c 100644
--- a/lib/PublicInbox/LeiALE.pm
+++ b/lib/PublicInbox/LeiALE.pm
@@ -9,7 +9,7 @@ package PublicInbox::LeiALE;
 use strict;
 use v5.10.1;
 use parent qw(PublicInbox::LeiSearch PublicInbox::Lock);
-use PublicInbox::Git;
+use PublicInbox::Git qw(read_all);
 use PublicInbox::Import;
 use PublicInbox::LeiXSearch;
 use Fcntl qw(SEEK_SET);
@@ -54,11 +54,7 @@ sub refresh_externals {
         $self->git->cleanup;
         my $lk = $self->lock_for_scope;
         my $cur_lxs = ref($lxs)->new;
-        my $orig = do {
-                local $/;
-                readline($self->{lockfh}) //
-                                die "readline($self->{lock_path}): $!";
-        };
+        my $orig = read_all($self->{lockfh});
         my $new = '';
         my $old = '';
         my $gone = 0;
@@ -91,8 +87,7 @@ sub refresh_externals {
         $new = $old = '';
         my $f = $self->git->{git_dir}.'/objects/info/alternates';
         if (open my $fh, '<', $f) {
-                local $/;
-                $old = <$fh> // die "readline($f): $!";
+                read_all($fh, -s $fh, \$old);
         }
         for my $x (@ibxish) {
                 $new .= $lei->canonpath_harder($x->git->{git_dir})."/objects\n";
diff --git a/lib/PublicInbox/LeiBlob.pm b/lib/PublicInbox/LeiBlob.pm
index d069d4a8..40f64bd9 100644
--- a/lib/PublicInbox/LeiBlob.pm
+++ b/lib/PublicInbox/LeiBlob.pm
@@ -10,6 +10,7 @@ use parent qw(PublicInbox::IPC);
 use PublicInbox::Spawn qw(run_wait popen_rd which);
 use PublicInbox::DS;
 use PublicInbox::Eml;
+use PublicInbox::Git qw(read_all);
 
 sub get_git_dir ($$) {
         my ($lei, $d) = @_;
@@ -137,9 +138,8 @@ sub lei_blob {
                                         extract_attach($lei, $blob, $bref) :
                                         $lei->out($$bref);
                 if ($opt->{mail}) {
-                        my $eh = $rdr->{2};
-                        seek($eh, 0, 0);
-                        return $lei->child_error($cerr, do { local $/; <$eh> });
+                        seek($rdr->{2}, 0, 0);
+                        return $lei->child_error($cerr, read_all($rdr->{2}));
                 } # else: fall through to solver below
         }
 
diff --git a/lib/PublicInbox/LeiConfig.pm b/lib/PublicInbox/LeiConfig.pm
index b3495487..c47708d8 100644
--- a/lib/PublicInbox/LeiConfig.pm
+++ b/lib/PublicInbox/LeiConfig.pm
@@ -28,7 +28,7 @@ sub cfg_edit_done { # PktOp lei->do_env cb
                 $lei->cfg_dump($self->{-f});
         } or do {
                 seek($fh, 0, SEEK_SET);
-                return cfg_do_edit($self, do { local $/; <$fh> });
+                return cfg_do_edit($self, read_all($fh));
         };
         $self->cfg_verify($cfg) if $self->can('cfg_verify');
 }
diff --git a/lib/PublicInbox/LeiMailSync.pm b/lib/PublicInbox/LeiMailSync.pm
index 415459d5..74ef1362 100644
--- a/lib/PublicInbox/LeiMailSync.pm
+++ b/lib/PublicInbox/LeiMailSync.pm
@@ -10,7 +10,7 @@ use PublicInbox::Compat qw(uniqstr);
 use DBI qw(:sql_types); # SQL_BLOB
 use PublicInbox::ContentHash qw(git_sha);
 use Carp ();
-use PublicInbox::Git qw(%HEXLEN2SHA);
+use PublicInbox::Git qw(%HEXLEN2SHA read_all);
 
 sub dbh_new {
         my ($self) = @_;
@@ -456,8 +456,7 @@ WHERE b.oidbin = ?
                         open my $fh, '<', $f or next;
                         # some (buggy) Maildir writers are non-atomic:
                         next unless -s $fh;
-                        local $/;
-                        my $raw = <$fh>;
+                        my $raw = read_all($fh, -s _);
                         if ($vrfy) {
                                 my $sha = $HEXLEN2SHA{length($oidhex)};
                                 my $got = git_sha($sha, \$raw)->hexdigest;
diff --git a/lib/PublicInbox/LeiSucks.pm b/lib/PublicInbox/LeiSucks.pm
index 35d0a8de..82aea8d4 100644
--- a/lib/PublicInbox/LeiSucks.pm
+++ b/lib/PublicInbox/LeiSucks.pm
@@ -12,6 +12,7 @@ use Config;
 use POSIX ();
 use PublicInbox::Config;
 use PublicInbox::IPC;
+use PublicInbox::Git qw(read_all);
 
 sub lei_sucks {
         my ($lei, @argv) = @_;
@@ -58,8 +59,8 @@ sub lei_sucks {
         for my $m (grep(m{^PublicInbox/}, sort keys %INC)) {
                 my $f = $INC{$m} // next; # lazy require failed (missing dep)
                 open my $fh, '<', $f or do { warn "open($f): $!"; next };
-                my $hex = sha1_hex('blob '.(-s $fh)."\0".
-                                (do { local $/; <$fh> } // die("read: $!")));
+                my $size = -s $fh;
+                my $hex = sha1_hex("blob $size\0".read_all($fh, $size));
                 push @out, '  '.$hex.' '.$m."\n";
         }
         push @out, <<'EOM';
diff --git a/lib/PublicInbox/MultiGit.pm b/lib/PublicInbox/MultiGit.pm
index 74a9e1df..35bd0251 100644
--- a/lib/PublicInbox/MultiGit.pm
+++ b/lib/PublicInbox/MultiGit.pm
@@ -9,6 +9,7 @@ use PublicInbox::Spawn qw(run_die popen_rd);
 use PublicInbox::Import;
 use File::Temp 0.19;
 use List::Util qw(max);
+use PublicInbox::Git qw(read_all);
 
 sub new {
         my ($cls, $topdir, $all, $epfx) = @_;
@@ -31,7 +32,7 @@ sub read_alternates {
                         qr!\A\Q../../$self->{epfx}\E/([0-9]+)\.git/objects\z! :
                         undef;
                 $$moderef = (stat($fh))[2] & 07777;
-                for my $rel (split(/^/m, do { local $/; <$fh> })) {
+                for my $rel (split(/^/m, read_all($fh, -s _))) {
                         chomp(my $dir = $rel);
                         my $score;
                         if (defined($is_edir) && $dir =~ $is_edir) {
diff --git a/lib/PublicInbox/ViewVCS.pm b/lib/PublicInbox/ViewVCS.pm
index 8a90c2d6..86c46e69 100644
--- a/lib/PublicInbox/ViewVCS.pm
+++ b/lib/PublicInbox/ViewVCS.pm
@@ -17,6 +17,7 @@ use strict;
 use v5.10.1;
 use File::Temp 0.19 (); # newdir
 use PublicInbox::SolverGit;
+use PublicInbox::Git qw(read_all);
 use PublicInbox::GitAsyncCat;
 use PublicInbox::WwwStream qw(html_oneshot);
 use PublicInbox::Linkify;
@@ -61,12 +62,9 @@ sub dbg_log ($) {
                 warn "seek(log): $!";
                 return '<pre>debug log seek error</pre>';
         }
-        $log = do { local $/; <$log> } // do {
-                if (!eof($log)) {
-                        warn "readline(log): $!";
-                        return '<pre>debug log read error</pre>';
-                }
-                '';
+        $log = eval { read_all($log) } // do {
+                warn "read(log): $@";
+                return '<pre>debug log read error</pre>';
         };
         return '' if $log eq '';
         $ctx->{-linkify} //= PublicInbox::Linkify->new;
@@ -251,7 +249,7 @@ EOM
         if (-s $fh > $MAX_SIZE) {
                 print $zfh "---\n patch is too large to show\n";
         } else { # prepare flush_diff:
-                read($fh, $x, -s _);
+                read_all($fh, -s _, \$x);
                 utf8_maybe($x);
                 $ctx->{-apfx} = $ctx->{-spfx} = $upfx;
                 $x =~ s/\r?\n/\n/gs;
diff --git a/lib/PublicInbox/WWW.pm b/lib/PublicInbox/WWW.pm
index 9919f975..86fd7e22 100644
--- a/lib/PublicInbox/WWW.pm
+++ b/lib/PublicInbox/WWW.pm
@@ -587,9 +587,9 @@ sub stylesheets_prepare ($$) {
                                 next;
                         };
                         my $ctime = 0;
-                        my $local = do { local $/; <$fh> };
+                        my $local = read_all($fh, -s $fh);
                         if ($local =~ /\S/) {
-                                $ctime = sprintf('%x',(stat($fh))[10]);
+                                $ctime = sprintf('%x',(stat(_))[10]);
                                 $local = $mini->($local);
                         }
 
diff --git a/lib/PublicInbox/XapHelper.pm b/lib/PublicInbox/XapHelper.pm
index ae907766..ca993ca8 100644
--- a/lib/PublicInbox/XapHelper.pm
+++ b/lib/PublicInbox/XapHelper.pm
@@ -10,6 +10,7 @@ $GLP->configure(qw(require_order bundling no_ignore_case no_auto_abbrev));
 use PublicInbox::Search qw(xap_terms);
 use PublicInbox::CodeSearch;
 use PublicInbox::IPC;
+use PublicInbox::Git qw(read_all);
 use Socket qw(SOL_SOCKET SO_TYPE SOCK_SEQPACKET AF_UNIX);
 use PublicInbox::DS qw(awaitpid);
 use POSIX qw(:signal_h);
@@ -123,7 +124,7 @@ sub cmd_dump_roots {
         $req->{A} or return warn('dump_roots requires -A PREFIX');
         open my $fh, '<', $root2id_file or die "open($root2id_file): $!";
         my $root2id; # record format: $OIDHEX "\0" uint32_t
-        my @x = split(/\0/, do { local $/; <$fh> } // die "readline: $!");
+        my @x = split(/\0/, read_all($fh));
         while (@x) {
                 my $oidhex = shift @x;
                 $root2id->{$oidhex} = shift @x;
diff --git a/lib/PublicInbox/XapHelperCxx.pm b/lib/PublicInbox/XapHelperCxx.pm
index dbb0a915..83015379 100644
--- a/lib/PublicInbox/XapHelperCxx.pm
+++ b/lib/PublicInbox/XapHelperCxx.pm
@@ -8,6 +8,7 @@
 package PublicInbox::XapHelperCxx;
 use v5.12;
 use PublicInbox::Spawn qw(popen_rd which);
+use PublicInbox::Git qw(read_all);
 use PublicInbox::Search;
 use Fcntl qw(SEEK_SET);
 use Config;
@@ -34,7 +35,7 @@ sub xap_cfg (@) {
         chomp(my $ret = do { local $/; <$rd> });
         return $ret if close($rd);
         seek($err, 0, SEEK_SET) or die "seek: $!";
-        $err = do { local $/; <$err> };
+        $err = read_all($err);
         die <<EOM;
 @$cmd failed: Xapian development files missing? (\$?=$?)
 $err
@@ -70,8 +71,7 @@ sub build () {
         for (@srcs) {
                 say $fh qq(# line 1 "$_");
                 open my $rfh, '<', $_;
-                local $/;
-                print $fh readline($rfh);
+                print $fh read_all($rfh);
         }
         print $fh PublicInbox::Search::generate_cxx();
         print $fh PublicInbox::CodeSearch::generate_cxx();