From: Amos Jeffries <squid3@treenet.co.nz>
Date: Tue, 17 Nov 2015 06:50:47 +0000 (-0800)
Subject: Update docs and make pop() check the context being removed
X-Git-Tag: SQUID_4_0_3~5^2~6
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1fad8490070a8dcee0757657f239b2157736f22f;p=thirdparty%2Fsquid.git

Update docs and make pop() check the context being removed
---

diff --git a/src/Pipeline.cc b/src/Pipeline.cc
index 15190d618c..c1c044d5dc 100644
--- a/src/Pipeline.cc
+++ b/src/Pipeline.cc
@@ -47,12 +47,15 @@ Pipeline::terminateAll(int xerrno)
 }
 
 void
-Pipeline::pop()
+Pipeline::popMe(const ClientSocketContextPointer &which)
 {
     if (requests.empty())
         return;
 
     debugs(33, 3, "Pipeline " << (void*)this << " drop " << requests.front());
+    // in reality there may be multiple contexts doing processing in parallel.
+    // XXX: pipeline still assumes HTTP/1 FIFO semantics are obeyed.
+    assert(which == requests.front());
     requests.pop_front();
 }
 
diff --git a/src/Pipeline.h b/src/Pipeline.h
index ae040e1dd5..de0e463345 100644
--- a/src/Pipeline.h
+++ b/src/Pipeline.h
@@ -17,16 +17,19 @@ class ClientSocketContext;
 typedef RefCount<ClientSocketContext> ClientSocketContextPointer;
 
 /**
- * A queue of requests awaiting completion.
+ * A queue of transactions awaiting completion.
  *
- * Requests in the queue may be fully processed, but not yet delivered,
+ * Transactions in the queue may be fully processed, but not yet delivered,
  * or only partially processed.
  *
  * - HTTP/1 pipelined requests can be processed out of order but
  *   responses MUST be written to the client in-order.
+ *   The front() context is for the response writing transaction.
+ *   The back context may still be reading a request payload/body.
+ *   Other contexts are in deferred I/O state, but may be accumulating
+ *   payload/body data to be written later.
  *
- * - HTTP/2 multiplexed streams (aka requests) can be processed
- *   and delivered in any order.
+ * - HTTP/2 multiplexed streams can be processed and delivered in any order.
  *
  * For consistency we treat the pipeline as a FIFO queue in both cases.
  */
@@ -55,7 +58,7 @@ public:
     void terminateAll(const int xerrno);
 
     /// deregister the front request from the pipeline
-    void pop();
+    void popMe(const ClientSocketContextPointer &);
 
     /// Number of requests seen in this pipeline (so far).
     /// Includes incomplete transactions.
diff --git a/src/client_side.cc b/src/client_side.cc
index 904d2f0714..c497fa471a 100644
--- a/src/client_side.cc
+++ b/src/client_side.cc
@@ -260,7 +260,7 @@ ClientSocketContext::finished()
     assert(connRegistered_);
     connRegistered_ = false;
     assert(conn->pipeline.front() == this); // XXX: still assumes HTTP/1 semantics
-    conn->pipeline.pop();
+    conn->pipeline.popMe(ClientSocketContext::Pointer(this));
     conn->kick(); // kick anything which was waiting for us to finish
 }
 
@@ -2342,7 +2342,7 @@ clientTunnelOnError(ConnStateData *conn, ClientSocketContext *context, HttpReque
             debugs(33, 3, "Request will be tunneled to server");
             if (context) {
                 assert(conn->pipeline.front() == context); // XXX: still assumes HTTP/1 semantics
-                conn->pipeline.pop();
+                conn->pipeline.popMe(ClientSocketContextPointer(context));
             }
             Comm::SetSelect(conn->clientConnection->fd, COMM_SELECT_READ, NULL, NULL, 0);
             conn->fakeAConnectRequest("unknown-protocol", conn->preservedClientData);