[gentoo-portage-dev] [PATCH] LinkageMapELF: compute mulilib category for preserved libs (bug 598080)

[Zac Medico]

When support for parsing ELF headers in order to compute multilib
category was added in commit f1c1b8a77eebf7713b32e5f9945690f60f4f46de,
the LinkageMapELF class was not updated to do the same for preserved
libraries. This has resulted in incorrect preserve-libs handling
as reported in bug 598080, for ABIs including x32 where the
_approx_multilib_categories mapping is insufficient. This patch fixes
LinkageMapELF to compute the multilib category for each preserved
library, in the same way as the _post_src_install_soname_symlinks
function, so that the LinkageMapELF.findConsumers method will operate
correctly with preserved libraries of all ABIs.

Fixes: f1c1b8a77eeb ("Generate soname dependency metadata (bug 282639)")
X-Gentoo-bug: 598080
X-Gentoo-bug-url: https://bugs.gentoo.org/598080
---
 pym/portage/util/_dyn_libs/LinkageMapELF.py | 33 +++++++++++++++++++++++------
 1 file changed, 26 insertions(+), 7 deletions(-)

diff --git a/pym/portage/util/_dyn_libs/LinkageMapELF.py b/pym/portage/util/_dyn_libs/LinkageMapELF.py
index 0b09fe5..a063621 100644
--- a/pym/portage/util/_dyn_libs/LinkageMapELF.py
+++ b/pym/portage/util/_dyn_libs/LinkageMapELF.py
@@ -4,6 +4,7 @@
 import errno
 import logging
 import subprocess
+import sys
 
 import portage
 from portage import _encodings
@@ -12,6 +13,7 @@ from portage import _unicode_decode
 from portage import _unicode_encode
 from portage.cache.mappings import slot_dict_class
 from portage.const import EPREFIX
+from portage.dep.soname.multilib_category import compute_multilib_category
 from portage.exception import CommandNotFound, InvalidData
 from portage.localization import _
 from portage.util import getlibpaths
@@ -20,6 +22,12 @@ from portage.util import normalize_path
 from portage.util import varexpand
 from portage.util import writemsg_level
 from portage.util._dyn_libs.NeededEntry import NeededEntry
+from portage.util.elf.header import ELFHeader
+
+if sys.hexversion >= 0x3000000:
+	_unicode = str
+else:
+	_unicode = unicode
 
 # Map ELF e_machine values from NEEDED.ELF.2 to approximate multilib
 # categories. This approximation will produce incorrect results on x32
@@ -283,15 +291,26 @@ class LinkageMapELF(object):
 					l = l[3:].rstrip("\n")
 					if not l:
 						continue
-					fields = l.split(";")
-					if len(fields) < 5:
-						writemsg_level(_("\nWrong number of fields " \
-							"returned from scanelf: %s\n\n") % (l,),
+					try:
+						entry = NeededEntry.parse("scanelf", l)
+					except InvalidData as e:
+						writemsg_level("\n%s\n\n" % (e,),
 							level=logging.ERROR, noiselevel=-1)
 						continue
-					fields[1] = fields[1][root_len:]
-					owner = plibs.pop(fields[1], None)
-					lines.append((owner, "scanelf", ";".join(fields)))
+					try:
+						with open(_unicode_encode(entry.filename,
+							encoding=_encodings['fs'],
+							errors='strict'), 'rb') as f:
+							elf_header = ELFHeader.read(f)
+					except EnvironmentError as e:
+						if e.errno != errno.ENOENT:
+							raise
+						# File removed concurrently.
+						continue
+					entry.multilib_category = compute_multilib_category(elf_header)
+					entry.filename = entry.filename[root_len:]
+					owner = plibs.pop(entry.filename, None)
+					lines.append((owner, "scanelf", _unicode(entry)))
 				proc.wait()
 				proc.stdout.close()
 
-- 
2.7.4