diff options
| -rw-r--r-- | meta/lib/oe/path.py | 87 | ||||
| -rw-r--r-- | meta/lib/oe/tests/test_path.py | 89 |
2 files changed, 176 insertions, 0 deletions
diff --git a/meta/lib/oe/path.py b/meta/lib/oe/path.py index ea58bedc8b..0b34cebdab 100644 --- a/meta/lib/oe/path.py +++ b/meta/lib/oe/path.py @@ -2,6 +2,7 @@ import errno import glob import shutil import subprocess +import os.path def join(*paths): """Like os.path.join but doesn't treat absolute RHS specially""" @@ -161,3 +162,89 @@ def find(dir, **walkoptions): for root, dirs, files in os.walk(dir, **walkoptions): for file in files: yield os.path.join(root, file) + + +## realpath() related functions +def __is_path_below(file, root): + return (file + os.path.sep).startswith(root) + +def __realpath_rel(start, rel_path, root, loop_cnt): + """Calculates real path of symlink 'start' + 'rel_path' below + 'root'; no part of 'start' below 'root' must contain symlinks. """ + have_dir = True + + for d in rel_path.split(os.path.sep): + if not have_dir: + raise OSError(errno.ENOENT, "no such directory %s" % start) + + if d == os.path.pardir: # '..' + if len(start) >= len(root): + # do not follow '..' before root + start = os.path.dirname(start) + else: + # emit warning? + pass + else: + (start, have_dir) = __realpath(os.path.join(start, d), + root, loop_cnt) + + assert(__is_path_below(start, root)) + + return start + +def __realpath(file, root, loop_cnt): + while os.path.islink(file) and len(file) >= len(root): + if loop_cnt == 0: + raise OSError(errno.ELOOP, file) + + loop_cnt -= 1 + target = os.path.normpath(os.readlink(file)) + + if not os.path.isabs(target): + tdir = os.path.dirname(file) + assert(__is_path_below(tdir, root)) + else: + tdir = root + + file = __realpath_rel(tdir, target, root, loop_cnt) + + try: + is_dir = os.path.isdir(file) + except: + is_dir = false + + return (file, is_dir) + +def realpath(file, root, use_physdir = True, loop_cnt = 100): + """ Returns the canonical path of 'file' with assuming a toplevel + 'root' directory. When 'use_physdir' is set, all preceding path + components of 'file' will be resolved first; this flag should be + set unless it is guaranteed that there is no symlink in the path.""" + + root = os.path.normpath(root) + file = os.path.normpath(file) + + if not root.endswith(os.path.sep): + # letting root end with '/' makes some things easier + root = root + os.path.sep + + if not __is_path_below(file, root): + raise OSError(errno.EINVAL, "file '%s' is not below root" % file) + + try: + if use_physdir: + file = __realpath_rel(root, file[(len(root) - 1):], root, loop_cnt) + else: + file = __realpath(file, root, loop_cnt)[0] + except OSError, e: + if e.errno == errno.ELOOP: + # make ELOOP more readable; without catching it, there will + # be printed a backtrace with 100s of OSError exceptions + # else + raise OSError(errno.ELOOP, + "too much recursions while resolving '%s'; loop in '%s'" % + (file, e.strerror)) + + raise + + return file diff --git a/meta/lib/oe/tests/test_path.py b/meta/lib/oe/tests/test_path.py new file mode 100644 index 0000000000..e6aa601618 --- /dev/null +++ b/meta/lib/oe/tests/test_path.py @@ -0,0 +1,89 @@ +import unittest +import oe, oe.path +import tempfile +import os +import errno +import shutil + +class TestRealPath(unittest.TestCase): + DIRS = [ "a", "b", "etc", "sbin", "usr", "usr/bin", "usr/binX", "usr/sbin", "usr/include", "usr/include/gdbm" ] + FILES = [ "etc/passwd", "b/file" ] + LINKS = [ + ( "bin", "/usr/bin", "/usr/bin" ), + ( "binX", "usr/binX", "/usr/binX" ), + ( "c", "broken", "/broken" ), + ( "etc/passwd-1", "passwd", "/etc/passwd" ), + ( "etc/passwd-2", "passwd-1", "/etc/passwd" ), + ( "etc/passwd-3", "/etc/passwd-1", "/etc/passwd" ), + ( "etc/shadow-1", "/etc/shadow", "/etc/shadow" ), + ( "etc/shadow-2", "/etc/shadow-1", "/etc/shadow" ), + ( "prog-A", "bin/prog-A", "/usr/bin/prog-A" ), + ( "prog-B", "/bin/prog-B", "/usr/bin/prog-B" ), + ( "usr/bin/prog-C", "../../sbin/prog-C", "/sbin/prog-C" ), + ( "usr/bin/prog-D", "/sbin/prog-D", "/sbin/prog-D" ), + ( "usr/binX/prog-E", "../sbin/prog-E", None ), + ( "usr/bin/prog-F", "../../../sbin/prog-F", "/sbin/prog-F" ), + ( "loop", "a/loop", None ), + ( "a/loop", "../loop", None ), + ( "b/test", "file/foo", None ), + ] + + LINKS_PHYS = [ + ( "./", "/", "" ), + ( "binX/prog-E", "/usr/sbin/prog-E", "/sbin/prog-E" ), + ] + + EXCEPTIONS = [ + ( "loop", errno.ELOOP ), + ( "b/test", errno.ENOENT ), + ] + + def __del__(self): + try: + #os.system("tree -F %s" % self.tmpdir) + shutil.rmtree(self.tmpdir) + except: + pass + + def setUp(self): + self.tmpdir = tempfile.mkdtemp(prefix = "oe-test_path") + self.root = os.path.join(self.tmpdir, "R") + + os.mkdir(os.path.join(self.tmpdir, "_real")) + os.symlink("_real", self.root) + + for d in self.DIRS: + os.mkdir(os.path.join(self.root, d)) + for f in self.FILES: + file(os.path.join(self.root, f), "w") + for l in self.LINKS: + os.symlink(l[1], os.path.join(self.root, l[0])) + + def __realpath(self, file, use_physdir): + return oe.path.realpath(os.path.join(self.root, file), self.root, use_physdir) + + def test_norm(self): + for l in self.LINKS: + if l[2] == None: + continue + + target_p = self.__realpath(l[0], True) + target_l = self.__realpath(l[0], False) + + if l[2] != False: + self.assertEqual(target_p, target_l) + self.assertEqual(l[2], target_p[len(self.root):]) + + def test_phys(self): + for l in self.LINKS_PHYS: + target_p = self.__realpath(l[0], True) + target_l = self.__realpath(l[0], False) + + self.assertEqual(l[1], target_p[len(self.root):]) + self.assertEqual(l[2], target_l[len(self.root):]) + + def test_loop(self): + for e in self.EXCEPTIONS: + self.assertRaisesRegexp(OSError, r'\[Errno %u\]' % e[1], + self.__realpath, e[0], False) + |