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	Wed, 29 Apr 2020 20:33:12 +0000 (UTC)
Date: Wed, 29 Apr 2020 20:33:11 +0000
From: Eric Wong <e@yhbt.net>
To: meta@public-inbox.org
Subject: Re: [PATCH] git: various minor speedups
Message-ID: <20200429203311.GA20984@dcvr>
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Eric Wong <e@yhbt.net> wrote:
> Best off all, there's less code :>

And even less...

> --- a/lib/PublicInbox/Git.pm
> +++ b/lib/PublicInbox/Git.pm
> @@ -125,59 +125,49 @@ sub _bidi_pipe {
>  	$self->{$in} = $in_r;
>  }
>  
> -sub read_cat_in_full ($$$) {
> -	my ($self, $in, $left) = @_;
> -	my $offset = 0;
> -	my $buf = '';
> -	while ($left > 0) {
> -		my $r = read($in, $buf, $left, $offset);
> -		defined($r) or fail($self, "read failed: $!");
> -		$r == 0 and fail($self, 'exited unexpectedly');
> -		$left -= $r;
> -		$offset += $r;
> -	}
> -	my $r = read($in, my $lf, 1);
> -	defined($r) or fail($self, "read failed: $!");
> -	fail($self, 'newline missing after blob') if ($r != 1 || $lf ne "\n");
> +sub read_cat_in_full ($$) {
> +	my ($self, $left) = @_;
> +	++$left; # for final "\n" added by git
> +	my $r = read($self->{in}, my $buf, $left) == $left or
> +		fail($self, 'short read');
> +	chop($buf) eq "\n" or fail($self, 'newline missing after blob');
>  	\$buf;
>  }

No need to save `$r', and `$len' makes a better name for
a single read() than `$left' with the new code.  Will squash
this in:

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index f1911534..057135ef 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -126,10 +126,9 @@ sub _bidi_pipe {
 }
 
 sub read_cat_in_full ($$) {
-	my ($self, $left) = @_;
-	++$left; # for final "\n" added by git
-	my $r = read($self->{in}, my $buf, $left) == $left or
-		fail($self, 'short read');
+	my ($self, $len) = @_;
+	++$len; # for final "\n" added by git
+	read($self->{in}, my $buf, $len) == $len or fail($self, 'short read');
 	chop($buf) eq "\n" or fail($self, 'newline missing after blob');
 	\$buf;
 }