1 files changed, 261 insertions, 0 deletions

diff --git a/meta/lib/oe/path.py b/meta/lib/oe/path.py
new file mode 100644
index 0000000000..1310e38fe1
--- /dev/null
+++ b/meta/lib/oe/path.py
@@ -0,0 +1,261 @@
+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"""
+    return os.path.normpath("/".join(paths))
+
+def relative(src, dest):
+    """ Return a relative path from src to dest.
+
+    >>> relative("/usr/bin", "/tmp/foo/bar")
+    ../../tmp/foo/bar
+
+    >>> relative("/usr/bin", "/usr/lib")
+    ../lib
+
+    >>> relative("/tmp", "/tmp/foo/bar")
+    foo/bar
+    """
+
+    if hasattr(os.path, "relpath"):
+        return os.path.relpath(dest, src)
+    else:
+        destlist = os.path.normpath(dest).split(os.path.sep)
+        srclist = os.path.normpath(src).split(os.path.sep)
+
+        # Find common section of the path
+        common = os.path.commonprefix([destlist, srclist])
+        commonlen = len(common)
+
+        # Climb back to the point where they differentiate
+        relpath = [ os.path.pardir ] * (len(srclist) - commonlen)
+        if commonlen < len(destlist):
+            # Add remaining portion
+            relpath += destlist[commonlen:]
+
+        return os.path.sep.join(relpath)
+
+def make_relative_symlink(path):
+    """ Convert an absolute symlink to a relative one """
+    if not os.path.islink(path):
+        return
+    link = os.readlink(path)
+    if not os.path.isabs(link):
+        return
+
+    # find the common ancestor directory
+    ancestor = path
+    depth = 0
+    while ancestor and not link.startswith(ancestor):
+        ancestor = ancestor.rpartition('/')[0]
+        depth += 1
+
+    if not ancestor:
+        print("make_relative_symlink() Error: unable to find the common ancestor of %s and its target" % path)
+        return
+
+    base = link.partition(ancestor)[2].strip('/')
+    while depth > 1:
+        base = "../" + base
+        depth -= 1
+
+    os.remove(path)
+    os.symlink(base, path)
+
+def format_display(path, metadata):
+    """ Prepare a path for display to the user. """
+    rel = relative(metadata.getVar("TOPDIR", True), path)
+    if len(rel) > len(path):
+        return path
+    else:
+        return rel
+
+def copytree(src, dst):
+    # We could use something like shutil.copytree here but it turns out to
+    # to be slow. It takes twice as long copying to an empty directory. 
+    # If dst already has contents performance can be 15 time slower
+    # This way we also preserve hardlinks between files in the tree.
+
+    bb.utils.mkdirhier(dst)
+    cmd = 'tar -cf - -C %s -p . | tar -xf - -C %s' % (src, dst)
+    check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+
+def copyhardlinktree(src, dst):
+    """ Make the hard link when possible, otherwise copy. """
+    bb.utils.mkdirhier(dst)
+    if os.path.isdir(src) and not len(os.listdir(src)):
+        return  
+
+    if (os.stat(src).st_dev ==  os.stat(dst).st_dev):
+        # Need to copy directories only with tar first since cp will error if two 
+        # writers try and create a directory at the same time
+        cmd = 'cd %s; find . -type d -print | tar -cf - -C %s -p --files-from - | tar -xf - -C %s' % (src, src, dst)
+        check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+        if os.path.isdir(src):
+            src = src + "/*"
+        cmd = 'cp -afl %s %s' % (src, dst)
+        check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+    else:
+        copytree(src, dst)
+
+def remove(path, recurse=True):
+    """Equivalent to rm -f or rm -rf"""
+    for name in glob.glob(path):
+        try:
+            os.unlink(name)
+        except OSError as exc:
+            if recurse and exc.errno == errno.EISDIR:
+                shutil.rmtree(name)
+            elif exc.errno != errno.ENOENT:
+                raise
+
+def symlink(source, destination, force=False):
+    """Create a symbolic link"""
+    try:
+        if force:
+            remove(destination)
+        os.symlink(source, destination)
+    except OSError as e:
+        if e.errno != errno.EEXIST or os.readlink(destination) != source:
+            raise
+
+class CalledProcessError(Exception):
+    def __init__(self, retcode, cmd, output = None):
+        self.retcode = retcode
+        self.cmd = cmd
+        self.output = output
+    def __str__(self):
+        return "Command '%s' returned non-zero exit status %d with output %s" % (self.cmd, self.retcode, self.output)
+
+# Not needed when we move to python 2.7
+def check_output(*popenargs, **kwargs):
+    r"""Run command with arguments and return its output as a byte string.
+
+    If the exit code was non-zero it raises a CalledProcessError.  The
+    CalledProcessError object will have the return code in the returncode
+    attribute and output in the output attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    >>> check_output(["ls", "-l", "/dev/null"])
+    'crw-rw-rw- 1 root root 1, 3 Oct 18  2007 /dev/null\n'
+
+    The stdout argument is not allowed as it is used internally.
+    To capture standard error in the result, use stderr=STDOUT.
+
+    >>> check_output(["/bin/sh", "-c",
+    ...               "ls -l non_existent_file ; exit 0"],
+    ...              stderr=STDOUT)
+    'ls: non_existent_file: No such file or directory\n'
+    """
+    if 'stdout' in kwargs:
+        raise ValueError('stdout argument not allowed, it will be overridden.')
+    process = subprocess.Popen(stdout=subprocess.PIPE, *popenargs, **kwargs)
+    output, unused_err = process.communicate()
+    retcode = process.poll()
+    if retcode:
+        cmd = kwargs.get("args")
+        if cmd is None:
+            cmd = popenargs[0]
+        raise CalledProcessError(retcode, cmd, output=output)
+    return output
+
+def find(dir, **walkoptions):
+    """ Given a directory, recurses into that directory,
+    returning all files as absolute paths. """
+
+    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, 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) = __realpath(os.path.join(start, d),
+                                           root, loop_cnt, assume_dir)
+
+        assert(__is_path_below(start, root))
+
+    return start
+
+def __realpath(file, root, loop_cnt, assume_dir):
+    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, assume_dir)
+
+    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, 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 __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, assume_dir)
+        else:
+            file = __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