From 254f3930e44c186ecd2a9b1c860ddbe9d16b183f Mon Sep 17 00:00:00 2001
From: rousskov <>
Date: Tue, 8 May 2007 22:37:59 +0000
Subject: [PATCH] 	Make sure the entire response body gets to ICAP, even
 when the 	end of it does not fit into the BodyPipe buffer.

	Re-enabled code that limits the amount of data the server may
	read depending on the available ICAP BodyPipe buffer size.
	While new BodyPipes limit the amount of data they accept, we
	still need the external limit because there is no code to keep
	pumping data into the pipe once the HTTP response ends and
	serverComplete() is called. If any body data is left in the
	HTTP server read buffer at the serverComplete() time, that data
	is lost and the client gets a truncated response.

	It is not clear whether it is better to stall the faster HTTP
	server I/O to let the slower ICAP server consume the body from
	the pipe OR to add code that will drain leftovers from the HTTP
	read buffer into the pipe.
---
 src/http.cc | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/http.cc b/src/http.cc
index 39997139f2..1924e5bbe0 100644
--- a/src/http.cc
+++ b/src/http.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: http.cc,v 1.520 2007/05/07 22:25:15 wessels Exp $
+ * $Id: http.cc,v 1.521 2007/05/08 16:37:59 rousskov Exp $
  *
  * DEBUG: section 11    Hypertext Transfer Protocol (HTTP)
  * AUTHOR: Harvest Derived
@@ -1237,17 +1237,18 @@ HttpStateData::maybeReadVirginBody()
     int read_sz = readBuf->spaceSize();
 
 #if ICAP_CLIENT
-#if RE_ENABLE_THIS_IF_NEEDED_OR_DELETE
-    // This code is not broken, but is probably not needed because we
-    // probably can read more than will fit into the BodyPipe buffer.
-
     if (virginBodyDestination != NULL) {
         /*
          * BodyPipe buffer has a finite size limit.  We
          * should not read more data from the network than will fit
-         * into the pipe buffer.  If totally full, don't register
-         * the read handler at all.  The ICAP side will call our
-         * icapSpaceAvailable() method when it has free space again.
+         * into the pipe buffer or we _lose_ what did not fit if
+         * the response ends sooner that BodyPipe frees up space:
+         * There is no code to keep pumping data into the pipe once
+         * response ends and serverComplete() is called.
+         *
+         * If the pipe is totally full, don't register the read handler.
+         * The BodyPipe will call our noteMoreBodySpaceAvailable() method
+         * when it has free space again.
          */
         int icap_space = virginBodyDestination->buf().potentialSpaceSize();
 
@@ -1257,8 +1258,6 @@ HttpStateData::maybeReadVirginBody()
         if (icap_space < read_sz)
             read_sz = icap_space;
     }
-
-#endif
 #endif
 
     debugs(11,9, HERE << (flags.do_next_read ? "may" : "wont") <<
-- 
2.47.2