* Introduce ap_proxy_transfer_between_connections

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1728478 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/modules/proxy/mod_proxy.h b/modules/proxy/mod_proxy.h
index 3f4ee651cbb5119c8d8e2c9407f806bc056c35d3..09671af22c61f6de419ada1acc62672041633ef4 100644 (file)
--- a/modules/proxy/mod_proxy.h
+++ b/modules/proxy/mod_proxy.h
@@ -1175,6 +1175,39 @@ PROXY_DECLARE(apr_status_t) ap_proxy_buckets_lifetime_transform(request_rec *r,
                                                       apr_bucket_brigade *from,
                                                       apr_bucket_brigade *to);
 
+/*
+ * Sends all data that can be read non blocking from the input filter chain of
+ * c_i and send it down the output filter chain of c_o. For reading it uses
+ * the bucket brigade bb_i which should be created from the bucket allocator
+ * associated with c_i. For sending through the output filter chain it uses
+ * the bucket brigade bb_o which should be created from the bucket allocator
+ * associated with c_o. In order to get the buckets from bb_i to bb_o
+ * ap_proxy_buckets_lifetime_transform is used.
+ *
+ * @param r     request_rec of the actual request. Used for logging purposes
+ * @param c_i   inbound connection conn_rec
+ * @param c_o   outbound connection conn_rec
+ * @param bb_i  bucket brigade for pulling data from the inbound connection
+ * @param bb_o  bucket brigade for sending data through the outbound connection
+ * @param name  string for logging from where data was pulled
+ * @param sent  if not NULL will be set to 1 if data was sent through c_o
+ * @param bsize maximum amount of data pulled in one iteration from c_i
+ * @param after if set flush data on c_o only once after the loop
+ * @return      apr_status_t of the operation. Could be any error returned from
+ *              either the input filter chain of c_i or the output filter chain
+ *              of c_o. APR_EPIPE if the outgoing connection was aborted.
+ */
+PROXY_DECLARE(apr_status_t) ap_proxy_transfer_between_connections(
+                                                       request_rec *r,
+                                                       conn_rec *c_i,
+                                                       conn_rec *c_o,
+                                                       apr_bucket_brigade *bb_i,
+                                                       apr_bucket_brigade *bb_o,
+                                                       const char *name,
+                                                       int *sent,
+                                                       apr_off_t bsize,
+                                                       int after);
+
 extern module PROXY_DECLARE_DATA proxy_module;
 
 #endif /*MOD_PROXY_H*/

diff --git a/modules/proxy/proxy_util.c b/modules/proxy/proxy_util.c
index 35e67f40d0badb5de6daee5e71965bc6935c77f6..92e0c9cd7a60ba599db01c54686962ef3e9a6b95 100644 (file)
--- a/modules/proxy/proxy_util.c
+++ b/modules/proxy/proxy_util.c
@@ -3735,6 +3735,90 @@ PROXY_DECLARE(apr_status_t) ap_proxy_buckets_lifetime_transform(request_rec *r,
     return rv;
 }
 
+PROXY_DECLARE(apr_status_t) ap_proxy_transfer_between_connections(
+                                                       request_rec *r,
+                                                       conn_rec *c_i,
+                                                       conn_rec *c_o,
+                                                       apr_bucket_brigade *bb_i,
+                                                       apr_bucket_brigade *bb_o,
+                                                       const char *name,
+                                                       int *sent,
+                                                       apr_off_t bsize,
+                                                       int after)
+{
+    apr_status_t rv;
+#ifdef DEBUGGING
+    apr_off_t len;
+#endif
+
+    do {
+        apr_brigade_cleanup(bb_i);
+        rv = ap_get_brigade(c_i->input_filters, bb_i, AP_MODE_READBYTES,
+                            APR_NONBLOCK_READ, bsize);
+        if (rv == APR_SUCCESS) {
+            if (c_o->aborted) {
+                return APR_EPIPE;
+            }
+            if (APR_BRIGADE_EMPTY(bb_i)) {
+                break;
+            }
+#ifdef DEBUGGING
+            len = -1;
+            apr_brigade_length(bb_i, 0, &len);
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO()
+                          "ap_proxy_transfer_between_connections: "
+                          "read %" APR_OFF_T_FMT
+                          " bytes from %s", len, name);
+#endif
+            if (sent) {
+                *sent = 1;
+            }
+            ap_proxy_buckets_lifetime_transform(r, bb_i, bb_o);
+            if (!after) {
+                apr_bucket *b;
+
+                /*
+                 * Do not use ap_fflush here since this would cause the flush
+                 * bucket to be sent in a separate brigade afterwards which
+                 * causes some filters to set aside the buckets from the first
+                 * brigade and process them when the flush arrives in the second
+                 * brigade. As set asides of our transformed buckets involve
+                 * memory copying we try to avoid this. If we have the flush
+                 * bucket in the first brigade they directly process the
+                 * buckets without setting them aside.
+                 */
+                b = apr_bucket_flush_create(bb_o->bucket_alloc);
+                APR_BRIGADE_INSERT_TAIL(bb_o, b);
+            }
+            rv = ap_pass_brigade(c_o->output_filters, bb_o);
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO()
+                              "ap_proxy_transfer_between_connections: "
+                              "error on %s - ap_pass_brigade",
+                              name);
+            }
+        } else if (!APR_STATUS_IS_EAGAIN(rv) && !APR_STATUS_IS_EOF(rv)) {
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO()
+                          "ap_proxy_transfer_between_connections: "
+                          "error on %s - ap_get_brigade",
+                          name);
+        }
+    } while (rv == APR_SUCCESS);
+
+    if (after) {
+        ap_fflush(c_o->output_filters, bb_o);
+    }
+
+    ap_log_rerror(APLOG_MARK, APLOG_TRACE2, rv, r,
+                  "ap_proxy_transfer_between_connections complete");
+
+    if (APR_STATUS_IS_EAGAIN(rv)) {
+        rv = APR_SUCCESS;
+    }
+
+    return rv;
+}
+
 void proxy_util_register_hooks(apr_pool_t *p)
 {
     APR_REGISTER_OPTIONAL_FN(ap_proxy_retry_worker);