t/integration.t: switch PUT tests to MD5, reuse buffers

MD5 is faster, and these tests aren't meant to be secure,
they're just for checking for data corruption.
Furthermore, Content-MD5 is a supported HTTP trailer and
we can verify that here to obsolete other tests.

Furthermore, we can reuse buffers on env['rack.input'].read
calls to avoid malloc(3) and GC overhead.

Combined, these give roughly a 3% speedup for t/integration.t
on my system.

3 files changed, 29 insertions, 13 deletions

diff --git a/t/integration.ru b/t/integration.ru
index dab384d..086126a 100644
--- a/t/integration.ru
+++ b/t/integration.ru
@@ -55,8 +55,8 @@ end
 def rack_input_tests(env)
   return [ 100, {}, [] ] if /\A100-continue\z/i =~ env['HTTP_EXPECT']
   cap = 16384
-  require 'digest/sha1'
-  digest = Digest::SHA1.new
+  require 'digest/md5'
+  dig = Digest::MD5.new
   input = env['rack.input']
   case env['PATH_INFO']
   when '/rack_input/size_first'; input.size
@@ -68,11 +68,21 @@ def rack_input_tests(env)
   if buf = input.read(rand(cap))
     begin
       raise "#{buf.size} > #{cap}" if buf.size > cap
-      digest.update(buf)
+      dig.update(buf)
     end while input.read(rand(cap), buf)
+    buf.clear # remove this call if Ruby ever gets escape analysis
   end
-  [ 200, {'content-length' => '40', 'content-type' => 'text/plain'},
-    [ digest.hexdigest ] ]
+  h = { 'content-type' => 'text/plain' }
+  if env['HTTP_TRAILER'] =~ /\bContent-MD5\b/i
+    cmd5_b64 = env['HTTP_CONTENT_MD5'] or return [500, {}, ['No Content-MD5']]
+    cmd5_bin = cmd5_b64.unpack('m')[0]
+    if cmd5_bin != dig.digest
+      h['content-length'] = cmd5_b64.size.to_s
+      return [ 500, h, [ cmd5_b64 ] ]
+    end
+  end
+  h['content-length'] = '32'
+  [ 200, h, [ dig.hexdigest ] ]
 end
 
 run(lambda do |env|
diff --git a/t/integration.t b/t/integration.t
index 8433497..38a9675 100644
--- a/t/integration.t
+++ b/t/integration.t
@@ -27,7 +27,6 @@ my %PUT = (
         chunked_md5 => sub {
                 my ($in, $out, $path, %opt) = @_;
                 my $bs = $opt{bs} // 16384;
-                require Digest::MD5;
                 my $dig = Digest::MD5->new;
                 print $out <<EOM;
 PUT $path HTTP/1.1\r
@@ -186,8 +185,8 @@ SKIP: {
         CORE::open(my $rh, '<', 't/random_blob') or
                 skip "t/random_blob not generated $!", 1;
         $blob_size = -s $rh;
-        require Digest::SHA;
-        $blob_hash = Digest::SHA->new(1)->addfile($rh)->hexdigest;
+        require Digest::MD5;
+        $blob_hash = Digest::MD5->new->addfile($rh)->hexdigest;
 
         my $ck_hash = sub {
                 my ($sub, $path, %opt) = @_;
diff --git a/t/preread_input.ru b/t/preread_input.ru
index f0a1748..18af221 100644
--- a/t/preread_input.ru
+++ b/t/preread_input.ru
@@ -1,15 +1,22 @@
 #\-E none
-require 'digest/sha1'
+require 'digest/md5'
 require 'unicorn/preread_input'
 use Unicorn::PrereadInput
 nr = 0
 run lambda { |env|
   $stderr.write "app dispatch: #{nr += 1}\n"
   input = env["rack.input"]
-  dig = Digest::SHA1.new
-  while buf = input.read(16384)
-    dig.update(buf)
+  dig = Digest::MD5.new
+  if buf = input.read(16384)
+    begin
+      dig.update(buf)
+    end while input.read(16384, buf)
+    buf.clear # remove this call if Ruby ever gets escape analysis
+  end
+  if env['HTTP_TRAILER'] =~ /\bContent-MD5\b/i
+    cmd5_b64 = env['HTTP_CONTENT_MD5'] or return [500, {}, ['No Content-MD5']]
+    cmd5_bin = cmd5_b64.unpack('m')[0]
+    return [500, {}, [ cmd5_b64 ] ] if cmd5_bin != dig.digest
   end
-
   [ 200, {}, [ dig.hexdigest ] ]
 }