sodepends: fix listing binaries, check libdepends, libprovides

• This fixes the problem when a library is needed by multiple binaries in a package, and only the last binary was listed, because the previous list was overridden on every scan.
• Check the sonames provided by the package and compare it with provides=() specified in PKGBUILD. Warn if provided but not specified, error if specified but not provided.
• Check the sonames required by the package and compare it with depends=() specified in PKGBUILD. Warn if a package provides a requred soname but not specified, and if a specified soname is not needed.

Namcap/rules/sodepends.py

@@ -35,41 +35,43 @@ from elftools.elf.dynamic import DynamicSection
 
 libcache = {'i686': {}, 'x86-64': {}}
 
-def scanlibs(fileobj, filename, custom_libs):
+def scanlibs(fileobj, filename, custom_libs, liblist, libdepends, libprovides):
 	"""
 	Find shared libraries in a file-like binary object
 
-	If it depends on a library, store that library's path.
-
-	returns: a dictionary { library => set(ELF files using that library) }
+	If it depends on a library or provides one, store that library's path.
 	"""
 
 	if not is_elf(fileobj):
 		return {}
 
 	elffile = ELFFile(fileobj)
-	sharedlibs = defaultdict(set)
 	for section in elffile.iter_sections():
 		if not isinstance(section, DynamicSection):
 			continue
 		for tag in section.iter_tags():
+			# DT_SONAME means it provides a library; ignore unversioned (mostly internal) libraries
+			if tag.entry.d_tag == 'DT_SONAME' and not tag.soname.endswith('.so'):
+				soname = tag.soname.rsplit('.so', 1)[0] + '.so'
+				libprovides[soname].add(filename)
 			# DT_NEEDED means shared library
 			if tag.entry.d_tag != 'DT_NEEDED':
 				continue
 			bitsize = elffile.elfclass
 			architecture = {32:'i686', 64:'x86-64'}[bitsize]
 			libname = tag.needed
+			soname = libname.rsplit('.so', 1)[0] + '.so'
+			libdepends[soname].add(filename)
 			if libname in custom_libs:
-				sharedlibs[custom_libs[libname][1:]].add(filename)
+				liblist[custom_libs[libname][1:]].add(filename)
 				continue
 			try:
 				libpath = os.path.abspath(
 						libcache[architecture][libname])[1:]
-				sharedlibs[libpath].add(filename)
+				liblist[libpath].add(filename)
 			except KeyError:
 				# We didn't know about the library, so add it for fail later
-				sharedlibs[libname].add(filename)
-	return sharedlibs
+				liblist[libname].add(filename)
 
 def finddepends(liblist):
 	"""
@@ -77,9 +79,13 @@ def finddepends(liblist):
 
 	Returns:
 	  dependlist -- a dictionary { package => set(libraries) }
+	  libdependlist -- a dictionary { soname => package }
 	  orphans -- the list of libraries without owners
+	  missing_provides -- the list of sonames without providers
 	"""
 	dependlist = defaultdict(set)
+	libdependlist = {}
+	missing_provides = {}
 
 	somatches = {}
 	actualpath = {}
@@ -108,9 +114,16 @@ def finddepends(liblist):
 				if j == actualpath[k] or (j.startswith(actualpath[k]) and so_end.match(j[len(actualpath[k]):])):
 					dependlist[pkg.name].add(k)
 					foundlibs.add(k)
+					# Check if the dependency can be satisfied by soname
+					soname = os.path.basename(k).rsplit('.so', 1)[0] + '.so'
+					stripped_provides = [Namcap.package.strip_depend_info(d) for d in pkg.provides]
+					if soname in stripped_provides:
+						libdependlist[soname] = pkg.name
+					else:
+						missing_provides[soname] = pkg.name
 
 	orphans = list(knownlibs - foundlibs)
-	return dependlist, orphans
+	return dependlist, libdependlist, orphans, missing_provides
 
 def filllibcache():
 	var = subprocess.Popen('ldconfig -p', 
@@ -133,8 +146,12 @@ class SharedLibsRule(TarballRule):
 	name = "sodepends"
 	description = "Checks dependencies caused by linked shared libraries"
 	def analyze(self, pkginfo, tar):
-		liblist = {}
+		liblist = defaultdict(set)
+		libdepends = defaultdict(set)
+		libprovides = defaultdict(set)
 		dependlist = {}
+		libdependlist = {}
+		missing_provides = {}
 		filllibcache()
 		os.environ['LC_ALL'] = 'C'
 		pkg_so_files = ['/' + n for n in tar.getnames() if '.so' in n]
@@ -151,16 +168,20 @@ class SharedLibsRule(TarballRule):
 				for n in pkg_so_files:
 					if any(n.startswith(rp) for rp in rpaths):
 						rpath_files[os.path.basename(n)] = n
-			liblist.update(scanlibs(f, entry.name, rpath_files))
+			scanlibs(f, entry.name, rpath_files, liblist, libdepends, libprovides)
 			f.close()
 
 		# Ldd all the files and find all the link and script dependencies
-		dependlist, orphans = finddepends(liblist)
+		dependlist, libdependlist, orphans, missing_provides = finddepends(liblist)
 
 		# Handle "no package associated" errors
 		self.warnings.extend([("library-no-package-associated %s", i)
 			for i in orphans])
 
+		# Hanle when a required soname does not provided by the associated package yet
+		self.infos.extend([("libdepends-missing-provides %s %s", (i, missing_provides[i]))
+			for i in missing_provides])
+
 		# Print link-level deps
 		for pkg, libraries in dependlist.items():
 			if isinstance(libraries, set):
@@ -173,6 +194,37 @@ class SharedLibsRule(TarballRule):
 					))
 				self.infos.append(("link-level-dependence %s in %s", (pkg, str(files))))
 
+		# Check for soname dependencies, filter out internal dependencies
+		libdependlist = dict(filter(lambda elem: elem[1] != pkginfo["name"], libdependlist.items()))
+
+		for i in libdependlist:
+			if i in pkginfo["depends"]:
+				self.infos.append(("libdepends-detected-satisfied %s %s (%s)", (i, libdependlist[i], str(list(libdepends[i])))))
+				continue
+			if i in pkginfo["optdepends"]:
+				self.warnings.append(("libdepends-detected-but-optional %s %s (%s)", (i, libdependlist[i], str(list(libdepends[i])))))
+				continue
+			self.warnings.append(("libdepends-detected-not-included %s %s (%s)", (i, libdependlist[i], str(list(libdepends[i])))))
+
+		for i in pkginfo["depends"]:
+			if i.endswith('.so') and i not in libdependlist:
+				self.warnings.append(("libdepends-not-needed %s", i))
+
+		self.infos.append(("libdepends-by-namcap-sight depends=(%s)", ' '.join(libdependlist) ))
+
+		# Check provided libraries
+		for i in libprovides:
+			if i in pkginfo["provides"]:
+				self.infos.append(("libprovides-satisfied %s %s", (i, str(list(libprovides[i])))))
+				continue
+			self.warnings.append(("libprovides-unsatisfied %s %s", (i, str(list(libprovides[i])))))
+
+		for i in pkginfo["provides"]:
+			if i.endswith('.so') and i not in libprovides:
+				self.errors.append(("libprovides-missing %s", i))
+
+		self.infos.append(("libprovides-by-namcap-sight provides=(%s)", ' '.join(libprovides) ))
+
 		# Check for packages in testing
 		for i in dependlist.keys():
 			p = Namcap.package.load_testing_package(i)