Merge the fcgi-proxy-dev branch to trunk, adding a FastCGI back end for

mod_proxy.  This log message is just a summary of the changes, for the
full original log messages see r357431:393955 in branches/fcgi-proxy-dev.

* modules/proxy/mod_proxy_fcgi.c: New file, holds the impementation of
  our new fcgi backend for mod_proxy.

* modules/proxy/fcgi_protocol.h: New file, holds constants and structures
  for the fcgi protocol.

* modules/proxy/mod_proxy_balancer.c
  (proxy_balancer_canon): Set up r->path_info, so the PATH_INFO env
   variable is correctly passed on to balancer workers.

* modules/proxy/config.m4: Build the new mod_proxy_fcgi module.

* support: Add fcgistarter to svn:ignore.

* support/Makefile.in: Build the new fcgistarter program.

* support/fcgistarter.c: New program, a helper for starting fcgi worker
  processes.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@396063 13f79535-47bb-0310-9956-ffa450edef68

modules/proxy/fcgi_protocol.h

@@ -0,0 +1,107 @@
+/* Copyright 2005 The Apache Software Foundation or its licensors, as
+ * applicable.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file fcgi_protocol.h
+ * @brief FastCGI protocol defines
+ *
+ * @addtogroup FCGI_defines
+ * @{
+ */
+
+#ifndef FCGI_PROTOCOL_H
+#define FCGI_PROTOCOL_H
+
+
+#define FCGI_VERSION 1
+
+#define FCGI_BEGIN_REQUEST       1
+#define FCGI_ABORT_REQUEST       2
+#define FCGI_END_REQUEST         3
+#define FCGI_PARAMS              4
+#define FCGI_STDIN               5
+#define FCGI_STDOUT              6
+#define FCGI_STDERR              7
+#define FCGI_DATA                8
+#define FCGI_GET_VALUES          9
+#define FCGI_GET_VALUES_RESULT  10
+#define FCGI_UNKNOWN_TYPE       11
+#define FCGI_MAXTYPE (FCGI_UNKNOWN_TYPE)
+
+typedef struct {
+    unsigned char version;
+    unsigned char type;
+    unsigned char requestIdB1;
+    unsigned char requestIdB0;
+    unsigned char contentLengthB1;
+    unsigned char contentLengthB0;
+    unsigned char paddingLength;
+    unsigned char reserved;
+} fcgi_header;
+
+#define FCGI_HDR_VERSION_OFFSET         0
+#define FCGI_HDR_TYPE_OFFSET            1
+#define FCGI_HDR_REQUEST_ID_B1_OFFSET   2
+#define FCGI_HDR_REQUEST_ID_B0_OFFSET   3
+#define FCGI_HDR_CONTENT_LEN_B1_OFFSET  4
+#define FCGI_HDR_CONTENT_LEN_B0_OFFSET  5
+#define FCGI_HDR_PADDING_LEN_OFFSET     6
+#define FCGI_HDR_RESERVED_OFFSET        7
+
+#define FCGI_BRB_ROLEB1_OFFSET       0
+#define FCGI_BRB_ROLEB0_OFFSET       1
+#define FCGI_BRB_FLAGS_OFFSET        2
+#define FCGI_BRB_RESERVED0_OFFSET    3
+#define FCGI_BRB_RESERVED1_OFFSET    4
+#define FCGI_BRB_RESERVED2_OFFSET    5
+#define FCGI_BRB_RESERVED3_OFFSET    6
+#define FCGI_BRB_RESERVED4_OFFSET    7
+
+/*
+ * Number of bytes in a fcgi_header.  Future versions of the protocol
+ * will not reduce this number.
+ */
+#define FCGI_HEADER_LEN  8
+
+/*
+ * Mask for flags component of FCGI_BeginRequestBody
+ */
+#define FCGI_KEEP_CONN  1
+
+/*
+ * Values for role component of FCGI_BeginRequestBody
+ */
+#define FCGI_RESPONDER  1
+#define FCGI_AUTHORIZER 2
+#define FCGI_FILTER     3
+
+typedef struct {
+    unsigned char roleB1;
+    unsigned char roleB0;
+    unsigned char flags;
+    unsigned char reserved[5];
+} fcgi_begin_request_body;
+
+/*
+ * Maximum size of the allowed environment.
+ */
+#define FCGI_MAX_ENV_SIZE  65535
+
+/* #define FCGI_DUMP_ENV_VARS */
+
+
+#endif /* FCGI_PROTOCOL_H */
+/** @} */