[PATCH mock] Allow installation when /dev is mounted read-only

[Enrico Scholz]

This patch bind-mounts a custom /etc/rpm directory to set the
%_netsharedpath macro before doing the 'yum install' operation.

Else, installation of filesystem package will fail due to a cpio error.

Signed-off-by: Enrico Scholz <enrico.scholz at informatik.tu-chemnitz.de>
---

 mock.py |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/mock.py b/mock.py
index 3762324..6061907 100644
--- a/mock.py
+++ b/mock.py
@@ -500,6 +500,7 @@ class Root:
         # mount /dev
         if self.config.get('dev-template'):
             self._mount('none --bind -o ro', self.config['dev-template'], 'dev')
+            self._mount('none --bind',       os.path.join(self.statedir, 'rpm'), '/etc/rpm')
 
         # mount /dev/pts
         self._mount('devpts', 'dev/pts', 'dev/pts')
@@ -698,7 +699,15 @@ class Root:
         ret = rpmUtils.miscutils.unique(reqlist)
         self.drop()
         return ret
-    
+
+    def __create_rpm_macros_for_install(self):
+        p     = os.path.join(self.statedir, 'rpm')
+        fname = os.path.join(p,             'macros')
+        if not os.path.exists(fname):
+            self._ensure_dir(p)
+            f = open(fname, 'w')
+            f.write(self._expand_macro_string({'%_netsharedpath' : '/dev'}))
+                           
     def _prep_install(self):
         """prep chroot for installation"""
         # make chroot dir
@@ -715,6 +724,7 @@ class Root:
                      os.path.join(self.rootdir, 'etc/yum.repos.d')]:
             self._ensure_dir(item)
 
+        self.__create_rpm_macros_for_install()
         self._mountall()
 
         if not self.config.get('dev-template'):