[nginx] Dynamic modules: do not overwrite old modules on install.

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/05c894a598ea
branches:  
changeset: 6425:05c894a598ea
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Thu Mar 10 16:50:13 2016 +0300
description:
Dynamic modules: do not overwrite old modules on install.

Just using "cp" is incorrect, as it will overwrite old files
possibly used by OS, leading to unexpected effects.  Changed
to "mv + cp", much like used for the main binary.

diffstat:

 auto/init    |   1 -
 auto/install |  18 ++++++++++++++++--
 auto/make    |   2 --
 3 files changed, 16 insertions(+), 5 deletions(-)

diffs (60 lines):

diff --git a/auto/init b/auto/init
--- a/auto/init
+++ b/auto/init
@@ -5,7 +5,6 @@
 
 NGX_MAKEFILE=$NGX_OBJS/Makefile
 NGX_MODULES_C=$NGX_OBJS/ngx_modules.c
-NGX_MODULES=
 
 NGX_AUTO_HEADERS_H=$NGX_OBJS/ngx_auto_headers.h
 NGX_AUTO_CONFIG_H=$NGX_OBJS/ngx_auto_config.h
diff --git a/auto/install b/auto/install
--- a/auto/install
+++ b/auto/install
@@ -169,17 +169,31 @@ END
 fi
 
 
-if test -n "$NGX_MODULES"; then
+if test -n "$DYNAMIC_MODULES"; then
     cat << END                                                >> $NGX_MAKEFILE
 
 	test -d '\$(DESTDIR)$NGX_MODULES_PATH' \
 		|| mkdir -p '\$(DESTDIR)$NGX_MODULES_PATH'
-	cp $NGX_MODULES '\$(DESTDIR)$NGX_MODULES_PATH'
 END
 
 fi
 
 
+for ngx_module in $DYNAMIC_MODULES
+do
+    ngx_module=$ngx_module$ngx_modext
+
+    cat << END                                                >> $NGX_MAKEFILE
+
+	test ! -f '\$(DESTDIR)$NGX_MODULES_PATH/$ngx_module' \
+		|| mv '\$(DESTDIR)$NGX_MODULES_PATH/$ngx_module' \
+			'\$(DESTDIR)$NGX_MODULES_PATH/$ngx_module.old'
+	cp $NGX_OBJS/$ngx_module '\$(DESTDIR)$NGX_MODULES_PATH/$ngx_module'
+END
+
+done
+
+
 # create Makefile
 
 cat << END >> Makefile
diff --git a/auto/make b/auto/make
--- a/auto/make
+++ b/auto/make
@@ -609,8 +609,6 @@ END
 
     ngx_obj=$NGX_OBJS$ngx_dirsep$ngx_module$ngx_modext
 
-    NGX_MODULES="$NGX_MODULES $ngx_obj"
-
     if [ "$NGX_PLATFORM" = win32 ]; then
         ngx_module_libs="$CORE_LIBS $ngx_module_libs"
     fi