[PATCH] ssl: disable copying for writes

[PATCH] ssl: disable copying for writes

[Eric Wong]

This is a partial revert of 551e670281bea77e727a732ba94275265ccae5f6
"fix output buffering with SSL_write".

With the patch to enable SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER
in <https://bugs.ruby-lang.org/issues/12126>, we can avoid
the hacky workaround we do.

We still implement our own trysendfile to avoid overhead
of string allocation kgio_trywrite and we still fill in
the missing kgio_trywritev addition.
---
  Consider this patch on hold.  Of course we cannot expect
  users to manually patch or run ruby-trunk in production.

  Pushed to the "ruby-accept_moving_write_buffer" branch
  in git://yhbt.net/yahns  I will rebase this branch as
  necessary.

 lib/yahns/openssl_client.rb | 23 ++++++-----------------
 1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/lib/yahns/openssl_client.rb b/lib/yahns/openssl_client.rb
index cd7d210..30ac0e0 100644
--- a/lib/yahns/openssl_client.rb
+++ b/lib/yahns/openssl_client.rb
@@ -36,18 +36,15 @@ def sync
   def yahns_init_ssl(ssl_ctx)
     @need_accept = true
     @ssl = OpenSSL::SSL::SSLSocket.new(self, ssl_ctx)
-    @ssl_blocked = nil
   end
 
   def kgio_trywrite(buf)
-    buf = @ssl_blocked = buf.dup
     case rv = @ssl.write_nonblock(buf, exception: false)
     when :wait_readable, :wait_writable
-      return rv # do not clear ssl_blocked
+      return rv
     when Integer
       rv = buf.bytesize == rv ? nil : buf.byteslice(rv, buf.bytesize - rv)
     end
-    @ssl_blocked = nil
     rv
   end
 
@@ -75,22 +72,14 @@ def kgio_tryread(len, buf)
   def trysendfile(io, offset, count)
     return 0 if count == 0
 
-    unless buf = @ssl_blocked
-      count = 0x4000 if count > 0x4000
-      buf = Thread.current[:yahns_sfbuf] ||= ''.dup
-      io.pos = offset
-      buf = io.read(count, buf) or return # nil for EOF
-      buf = @ssl_blocked = buf.dup
-    end
+    count = 0x4000 if count > 0x4000
+    buf = Thread.current[:yahns_sfbuf] ||= ''.dup
+    io.pos = offset
+    buf = io.read(count, buf) or return # nil for EOF
 
     # call write_nonblock directly since kgio_trywrite allocates
     # an unnecessary string
-    case rv = @ssl.write_nonblock(buf, exception: false)
-    when :wait_readable, :wait_writable
-      return rv # do not clear ssl_blocked
-    end
-    @ssl_blocked = nil
-    rv
+    @ssl.write_nonblock(buf, exception: false)
   end
 
   def close
-- 
EW