Test for read-only filesystems, fixes bug 378869
If any read-only filesystems need writing, bail out and display a
useful error message.
v2: Reformat, add a function to return an appropriate read-only checker
for the operating system, so that this can be extended to other OSes.
v3: minor formatting tweaks from bernalex, including use os.path.join()
instead of string concatenation
v4: Update copyright header, change the code in rochecker to open with
io.open in order to not break on non-ascii characters as reported by
Arfrever. Change get_ro_checker to use a dict as suggested by vapier.
v5: Fix comment format as requested by vapier.
v6: Change linux_ro_checker to use set.intersection instead of the
longer check-and-append system as suggested by vapier.
v7: rename rochecker -> writeable_check
diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py
index ed62323..7a4a3d2 100644
--- a/pym/portage/dbapi/vartree.py
+++ b/pym/portage/dbapi/vartree.py
@@ -1,4 +1,4 @@
-# Copyright 1998-2013 Gentoo Foundation
+# Copyright 1998-2014 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
from __future__ import unicode_literals
@@ -32,6 +32,7 @@
'portage.util.env_update:env_update',
'portage.util.listdir:dircache,listdir',
'portage.util.movefile:movefile',
+ 'portage.util.writeable_check:get_ro_checker',
'portage.util._dyn_libs.PreservedLibsRegistry:PreservedLibsRegistry',
'portage.util._dyn_libs.LinkageMapELF:LinkageMapELF@LinkageMap',
'portage.util._async.SchedulerInterface:SchedulerInterface',
@@ -3508,6 +3509,8 @@
This function does the following:
+ calls get_ro_checker to retrieve a function for checking whether Portage
+ will write to a read-only filesystem, then runs it against the directory list
calls self._preserve_libs if FEATURES=preserve-libs
calls self._collision_protect if FEATURES=collision-protect
calls doebuild(mydo=pkg_preinst)
@@ -3685,6 +3688,7 @@
eagain_error = False
myfilelist = []
+ mydirlist = []
mylinklist = []
paths_with_newlines = []
def onerror(e):
@@ -3717,6 +3721,9 @@
unicode_errors.append(new_parent[ed_len:])
break
+ relative_path = parent[srcroot_len:]
+ mydirlist.append(os.path.join("/", relative_path))
+
for fname in files:
try:
fname = _unicode_decode(fname,
@@ -3829,6 +3836,31 @@
for other in others_in_slot])
prepare_build_dirs(settings=self.settings, cleanup=cleanup)
+ # Check for read-only filesystems.
+ ro_checker = get_ro_checker()
+ rofilesystems = ro_checker(mydirlist)
+
+ if rofilesystems:
+ msg = _("One or more files installed to this package are "
+ "set to be installed to read-only filesystems. "
+ "Please mount the following filesystems as read-write "
+ "and retry.")
+ msg = textwrap.wrap(msg, 70)
+ msg.append("")
+ for f in rofilesystems:
+ msg.append("\t%s" % os.path.join(destroot,
+ f.lstrip(os.path.sep)))
+ msg.append("")
+ self._elog("eerror", "preinst", msg)
+
+ msg = _("Package '%s' NOT merged due to read-only file systems.") % \
+ self.settings.mycpv
+ msg += _(" If necessary, refer to your elog "
+ "messages for the whole content of the above message.")
+ msg = textwrap.wrap(msg, 70)
+ eerror(msg)
+ return 1
+
# check for package collisions
blockers = self._blockers
if blockers is None:
diff --git a/pym/portage/util/writeable_check.py b/pym/portage/util/writeable_check.py
new file mode 100644
index 0000000..e6ddce6
--- /dev/null
+++ b/pym/portage/util/writeable_check.py
@@ -0,0 +1,79 @@
+#-*- coding:utf-8 -*-
+# Copyright 2014 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+"""
+Methods to check whether Portage is going to write to read-only filesystems.
+Since the methods are not portable across different OSes, each OS needs its
+own method. To expand RO checking for different OSes, add a method which
+accepts a list of directories and returns a list of mounts which need to be
+remounted RW, then add "elif ostype == (the ostype value for your OS)" to
+get_ro_checker().
+"""
+from __future__ import unicode_literals
+
+import io
+import logging
+import re
+
+from portage import _encodings
+from portage.util import writemsg_level
+from portage.localization import _
+from portage.data import ostype
+
+
+def get_ro_checker():
+ """
+ Uses the system type to find an appropriate method for testing whether Portage
+ is going to write to any read-only filesystems.
+
+ @return:
+ 1. A method for testing for RO filesystems appropriate to the current system.
+ """
+ return _CHECKERS.get(ostype, empty_ro_checker)
+
+
+def linux_ro_checker(dir_list):
+ """
+ Use /proc/mounts to check that no directories installed by the ebuild are set
+ to be installed to a read-only filesystem.
+
+ @param dir_list: A list of directories installed by the ebuild.
+ @type dir_list: List
+ @return:
+ 1. A list of filesystems which are both set to be written to and are mounted
+ read-only, may be empty.
+ """
+ ro_filesystems = set()
+
+ try:
+ with io.open("/proc/mounts", mode='r', encoding=_encodings['content'],
+ errors='replace') as f:
+ roregex = re.compile(r'(\A|,)ro(\Z|,)')
+ for line in f:
+ if roregex.search(line.split(" ")[3].strip()) is not None:
+ romount = line.split(" ")[1].strip()
+ ro_filesystems.add(romount)
+
+ # If /proc/mounts can't be read, assume that there are no RO
+ # filesystems and return.
+ except EnvironmentError:
+ writemsg_level(_("!!! /proc/mounts cannot be read"),
+ level=logging.WARNING, noiselevel=-1)
+ return []
+
+ return set.intersection(ro_filesystems, set(dir_list))
+
+
+def empty_ro_checker(dir_list):
+ """
+ Always returns [], this is the fallback function if the system does not have
+ an ro_checker method defined.
+ """
+ return []
+
+
+# _CHECKERS is a map from ostype output to the appropriate function to return
+# in get_ro_checker.
+_CHECKERS = {
+ "Linux": linux_ro_checker,
+}
