[PATCH 6 of 8] Added new run-time prefix option for configure files

[Per Olav Høydahl Ohme]

# HG changeset patch
# User Per Olav Hoydahl Ohme <phoydahl at cisco.com>
# Date 1405683324 -7200
#      Fri Jul 18 13:35:24 2014 +0200
# Node ID 0d4f62e2c8115cb0d8b372fcabe7e8582a54d299
# Parent  fae8ad3d60a2e4ffeac836eb4c05cf29f39c0824
Added new run-time prefix option for configure files.
Needed in case configure files are relocated after build.

diff -r fae8ad3d60a2 -r 0d4f62e2c811 auto/configure
--- a/auto/configure	Fri Jul 18 13:35:24 2014 +0200
+++ b/auto/configure	Fri Jul 18 13:35:24 2014 +0200
@@ -79,6 +79,9 @@
 if [ ".$NGX_CONF_PREFIX" != "." ]; then
     have=NGX_CONF_PREFIX value="\"$NGX_CONF_PREFIX/\"" . auto/define
 fi
+if [ "$NGX_RT_CONF_PREFIX" ]; then
+    have=NGX_RT_CONF_PREFIX value="\"$NGX_RT_CONF_PREFIX\"" . auto/define
+fi
 
 have=NGX_SBIN_PATH value="\"$NGX_SBIN_PATH\"" . auto/define
 have=NGX_CONF_PATH value="\"$NGX_CONF_PATH\"" . auto/define
diff -r fae8ad3d60a2 -r 0d4f62e2c811 auto/options
--- a/auto/options	Fri Jul 18 13:35:24 2014 +0200
+++ b/auto/options	Fri Jul 18 13:35:24 2014 +0200
@@ -9,6 +9,7 @@
 NGX_SBIN_PATH=
 NGX_CONF_PREFIX=
 NGX_CONF_PATH=
+NGX_RT_CONF_PREFIX=
 NGX_ERROR_LOG_PATH=
 NGX_PID_PATH=
 NGX_LOCK_PATH=
@@ -182,6 +183,7 @@
         --prefix=*)                      NGX_PREFIX="$value"        ;;
         --sbin-path=*)                   NGX_SBIN_PATH="$value"     ;;
         --conf-path=*)                   NGX_CONF_PATH="$value"     ;;
+        --rt-conf-prefix=*)              NGX_RT_CONF_PREFIX="$value";;
         --error-log-path=*)              NGX_ERROR_LOG_PATH="$value";;
         --pid-path=*)                    NGX_PID_PATH="$value"      ;;
         --lock-path=*)                   NGX_LOCK_PATH="$value"     ;;
@@ -365,6 +367,7 @@
                                      worker processes
 
   --crossbuild=PLATFORM              set target platform for crossbuild
+  --rt-conf-prefix=PATH              set run-time prefix for configure files
 
   --build=NAME                       set build name
   --builddir=DIR                     set build directory
diff -r fae8ad3d60a2 -r 0d4f62e2c811 src/core/ngx_conf_file.c
--- a/src/core/ngx_conf_file.c	Fri Jul 18 13:35:24 2014 +0200
+++ b/src/core/ngx_conf_file.c	Fri Jul 18 13:35:24 2014 +0200
@@ -120,6 +120,18 @@
 
         /* open configuration file */
 
+#ifdef NGX_RT_CONF_PREFIX
+        char rt_prefixed_data[512];
+        snprintf(rt_prefixed_data, 512, "%s%s", NGX_RT_CONF_PREFIX,
+                 filename->data);
+        fd = ngx_open_file(rt_prefixed_data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
+        if (fd == NGX_INVALID_FILE) {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
+                               ngx_open_file_n " \"%s\" failed",
+                               rt_prefixed_data);
+            return NGX_CONF_ERROR;
+        }
+#else
         fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
         if (fd == NGX_INVALID_FILE) {
             ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
@@ -127,6 +139,7 @@
                                filename->data);
             return NGX_CONF_ERROR;
         }
+#endif
 
         prev = cf->conf_file;