Squashed 'yocto-poky/' content from commit ea562de
git-subtree-dir: yocto-poky
git-subtree-split: ea562de57590c966cd5a75fda8defecd397e6436
diff --git a/meta/lib/oe/cachedpath.py b/meta/lib/oe/cachedpath.py
new file mode 100644
index 0000000..0840cc4
--- /dev/null
+++ b/meta/lib/oe/cachedpath.py
@@ -0,0 +1,233 @@
+#
+# Based on standard python library functions but avoid
+# repeated stat calls. Its assumed the files will not change from under us
+# so we can cache stat calls.
+#
+
+import os
+import errno
+import stat as statmod
+
+class CachedPath(object):
+ def __init__(self):
+ self.statcache = {}
+ self.lstatcache = {}
+ self.normpathcache = {}
+ return
+
+ def updatecache(self, x):
+ x = self.normpath(x)
+ if x in self.statcache:
+ del self.statcache[x]
+ if x in self.lstatcache:
+ del self.lstatcache[x]
+
+ def normpath(self, path):
+ if path in self.normpathcache:
+ return self.normpathcache[path]
+ newpath = os.path.normpath(path)
+ self.normpathcache[path] = newpath
+ return newpath
+
+ def _callstat(self, path):
+ if path in self.statcache:
+ return self.statcache[path]
+ try:
+ st = os.stat(path)
+ self.statcache[path] = st
+ return st
+ except os.error:
+ self.statcache[path] = False
+ return False
+
+ # We might as well call lstat and then only
+ # call stat as well in the symbolic link case
+ # since this turns out to be much more optimal
+ # in real world usage of this cache
+ def callstat(self, path):
+ path = self.normpath(path)
+ self.calllstat(path)
+ return self.statcache[path]
+
+ def calllstat(self, path):
+ path = self.normpath(path)
+ if path in self.lstatcache:
+ return self.lstatcache[path]
+ #bb.error("LStatpath:" + path)
+ try:
+ lst = os.lstat(path)
+ self.lstatcache[path] = lst
+ if not statmod.S_ISLNK(lst.st_mode):
+ self.statcache[path] = lst
+ else:
+ self._callstat(path)
+ return lst
+ except (os.error, AttributeError):
+ self.lstatcache[path] = False
+ self.statcache[path] = False
+ return False
+
+ # This follows symbolic links, so both islink() and isdir() can be true
+ # for the same path ono systems that support symlinks
+ def isfile(self, path):
+ """Test whether a path is a regular file"""
+ st = self.callstat(path)
+ if not st:
+ return False
+ return statmod.S_ISREG(st.st_mode)
+
+ # Is a path a directory?
+ # This follows symbolic links, so both islink() and isdir()
+ # can be true for the same path on systems that support symlinks
+ def isdir(self, s):
+ """Return true if the pathname refers to an existing directory."""
+ st = self.callstat(s)
+ if not st:
+ return False
+ return statmod.S_ISDIR(st.st_mode)
+
+ def islink(self, path):
+ """Test whether a path is a symbolic link"""
+ st = self.calllstat(path)
+ if not st:
+ return False
+ return statmod.S_ISLNK(st.st_mode)
+
+ # Does a path exist?
+ # This is false for dangling symbolic links on systems that support them.
+ def exists(self, path):
+ """Test whether a path exists. Returns False for broken symbolic links"""
+ if self.callstat(path):
+ return True
+ return False
+
+ def lexists(self, path):
+ """Test whether a path exists. Returns True for broken symbolic links"""
+ if self.calllstat(path):
+ return True
+ return False
+
+ def stat(self, path):
+ return self.callstat(path)
+
+ def lstat(self, path):
+ return self.calllstat(path)
+
+ def walk(self, top, topdown=True, onerror=None, followlinks=False):
+ # Matches os.walk, not os.path.walk()
+
+ # We may not have read permission for top, in which case we can't
+ # get a list of the files the directory contains. os.path.walk
+ # always suppressed the exception then, rather than blow up for a
+ # minor reason when (say) a thousand readable directories are still
+ # left to visit. That logic is copied here.
+ try:
+ names = os.listdir(top)
+ except os.error as err:
+ if onerror is not None:
+ onerror(err)
+ return
+
+ dirs, nondirs = [], []
+ for name in names:
+ if self.isdir(os.path.join(top, name)):
+ dirs.append(name)
+ else:
+ nondirs.append(name)
+
+ if topdown:
+ yield top, dirs, nondirs
+ for name in dirs:
+ new_path = os.path.join(top, name)
+ if followlinks or not self.islink(new_path):
+ for x in self.walk(new_path, topdown, onerror, followlinks):
+ yield x
+ if not topdown:
+ yield top, dirs, nondirs
+
+ ## realpath() related functions
+ def __is_path_below(self, file, root):
+ return (file + os.path.sep).startswith(root)
+
+ def __realpath_rel(self, start, rel_path, root, loop_cnt, assume_dir):
+ """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 and not assume_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) = self.__realpath(os.path.join(start, d),
+ root, loop_cnt, assume_dir)
+
+ assert(self.__is_path_below(start, root))
+
+ return start
+
+ def __realpath(self, file, root, loop_cnt, assume_dir):
+ while self.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(self.__is_path_below(tdir, root))
+ else:
+ tdir = root
+
+ file = self.__realpath_rel(tdir, target, root, loop_cnt, assume_dir)
+
+ try:
+ is_dir = self.isdir(file)
+ except:
+ is_dir = False
+
+ return (file, is_dir)
+
+ def realpath(self, file, root, use_physdir = True, loop_cnt = 100, assume_dir = False):
+ """ 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. When 'assume_dir' is not set, missing
+ path components will raise an ENOENT error"""
+
+ 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 self.__is_path_below(file, root):
+ raise OSError(errno.EINVAL, "file '%s' is not below root" % file)
+
+ try:
+ if use_physdir:
+ file = self.__realpath_rel(root, file[(len(root) - 1):], root, loop_cnt, assume_dir)
+ else:
+ file = self.__realpath(file, root, loop_cnt, assume_dir)[0]
+ except OSError as 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