[PATCH] insane.bbclass: Fix RPATH warning in the face of funny path strings

[Andy Ross <andy.ross@windriver.com>]

In toolchain edge cases it's possible for the RPATH of a library to be
set to something like "/usr/lib/../lib".  This should be detected as
"/usr/lib" and generate a warning.  Also clarify the warning text to
indicate potential link-time pollution from the host libraries.

Signed-off-by: Andy Ross <andy.ross@windriver.com>
---
 meta/classes/insane.bbclass | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/meta/classes/insane.bbclass b/meta/classes/insane.bbclass
index 556a176..ade0616 100644
--- a/meta/classes/insane.bbclass
+++ b/meta/classes/insane.bbclass
@@ -161,6 +161,17 @@ def package_qa_check_rpath(file,name, d, elf, messages):
             if dir in line:
                 messages.append("package %s contains bad RPATH %s in file %s" % (name, line, file))
 
+def rpath_norm(s):
+    import re
+    s = re.sub('[^/]+/\.\.(/|$)', '/', s) # snip ".." components
+    s = re.sub('/\.(/|$)', '/', s)        # snip "." components
+    s = re.sub('/+', '/', s)              # snip repeated slashes
+    s = re.sub('/$', '', s)               # snip trailing slash
+    return s
+
+def rpath_eq(a, b):
+    return rpath_norm(a) == rpath_norm(b)
+
 QAPATHTEST[useless-rpaths] = "package_qa_check_useless_rpaths"
 def package_qa_check_useless_rpaths(file, name, d, elf, messages):
     """
@@ -181,10 +192,13 @@ def package_qa_check_useless_rpaths(file, name, d, elf, messages):
     	m = rpath_re.match(line)
 	if m:
 	   rpath = m.group(1)
-	   if rpath == libdir or rpath == base_libdir:
-	      # The dynamic linker searches both these places anyway.  There is no point in
-	      # looking there again.
-	      messages.append("%s: %s contains probably-redundant RPATH %s" % (name, package_qa_clean_path(file, d), rpath))
+	   if rpath_eq(rpath, libdir) or rpath_eq(rpath, base_libdir):
+	      # The dynamic linker searches both these places anyway.
+	      # There is no point in looking there again.  And it may
+	      # be harmful: the RPATH may point to host directories
+	      # (e.g. /usr/lib) which will be searched at link time,
+	      # creating build issues.
+	      messages.append("%s: %s contains probably-redundant, possibly host-polluted RPATH %s" % (name, package_qa_clean_path(file, d), rpath))
 
 QAPATHTEST[dev-so] = "package_qa_check_dev"
 def package_qa_check_dev(path, name, d, elf, messages):
-- 
1.7.11.2