treewide: reduce $PATH checks for `git' executable HEAD master

Repeatedly checking $PATH for `git' when we need to call it
multiple times in quick succession doesn't seem useful.  So
avoid some expensive stat(2) syscalls to make things less bad
for systems which require expensive CPU vulnerability
mitigations.

This also saves a bunch of memory allocations since we do the
$PATH lookup in pure Perl to avoid doing the uncacheable lookup
in a vfork-ed child.

1 files changed, 6 insertions, 8 deletions

diff --git a/lib/PublicInbox/ViewVCS.pm b/lib/PublicInbox/ViewVCS.pm
index f47c2703..83a83698 100644
--- a/lib/PublicInbox/ViewVCS.pm
+++ b/lib/PublicInbox/ViewVCS.pm
@@ -106,7 +106,7 @@ sub stream_large_blob ($$) {
         my ($ctx, $res) = @_;
         $ctx->{-res} = $res;
         my ($git, $oid, $type, $size, $di) = @$res;
-        my $cmd = ['git', "--git-dir=$git->{git_dir}", 'cat-file', $type, $oid];
+        my $cmd = $git->cmd('cat-file', $type, $oid);
         my $qsp = PublicInbox::Qspawn->new($cmd);
         $ctx->{env}->{'qspawn.wcb'} = $ctx->{-wcb};
         $qsp->psgi_yield($ctx->{env}, undef, \&stream_blob_parse_hdr, $ctx);
@@ -368,10 +368,9 @@ sub stream_patch_parse_hdr { # {parse_hdr} for Qspawn
 sub show_patch ($$) {
         my ($ctx, $res) = @_;
         my ($git, $oid) = @$res;
-        my @cmd = ('git', "--git-dir=$git->{git_dir}",
-                qw(format-patch -1 --stdout -C),
+        my $cmd = $git->cmd(qw(format-patch -1 --stdout -C),
                 "--signature=git format-patch -1 --stdout -C $oid", $oid);
-        my $qsp = PublicInbox::Qspawn->new(\@cmd);
+        my $qsp = PublicInbox::Qspawn->new($cmd);
         $ctx->{env}->{'qspawn.wcb'} = $ctx->{-wcb};
         $ctx->{patch_oid} = $oid;
         $qsp->psgi_yield($ctx->{env}, undef, \&stream_patch_parse_hdr, $ctx);
@@ -400,8 +399,8 @@ sub show_other ($$) { # just in case...
         my ($git, $oid, $type, $size) = @$res;
         $size > $MAX_SIZE and return html_page($ctx, 200,
                 ascii_html($type)." $oid is too big to show\n". dbg_log($ctx));
-        my $cmd = ['git', "--git-dir=$git->{git_dir}",
-                qw(show --encoding=UTF-8 --no-color --no-abbrev), $oid ];
+        my $cmd = $git->cmd(qw(show --encoding=UTF-8
+                        --no-color --no-abbrev), $oid);
         my $qsp = PublicInbox::Qspawn->new($cmd);
         $qsp->{qsp_err} = \($ctx->{-qsp_err} = '');
         $qsp->psgi_qx($ctx->{env}, undef, \&show_other_result, $ctx);
@@ -487,8 +486,7 @@ sub show_tree ($$) { # also used by RepoTree
         my ($git, $oid, undef, $size) = @$res;
         $size > $MAX_SIZE and return html_page($ctx, 200,
                         "tree $oid is too big to show\n". dbg_log($ctx));
-        my $cmd = [ 'git', "--git-dir=$git->{git_dir}",
-                qw(ls-tree -z -l --no-abbrev), $oid ];
+        my $cmd = $git->cmd(qw(ls-tree -z -l --no-abbrev), $oid);
         my $qsp = PublicInbox::Qspawn->new($cmd);
         $ctx->{tree_oid} = $oid;
         $qsp->{qsp_err} = \($ctx->{-qsp_err} = '');