diff options
Diffstat (limited to 'import-layers/yocto-poky/meta/lib/oe/path.py')
| -rw-r--r-- | import-layers/yocto-poky/meta/lib/oe/path.py | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/import-layers/yocto-poky/meta/lib/oe/path.py b/import-layers/yocto-poky/meta/lib/oe/path.py new file mode 100644 index 000000000..413ebfb39 --- /dev/null +++ b/import-layers/yocto-poky/meta/lib/oe/path.py @@ -0,0 +1,243 @@ +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 + """ + + return os.path.relpath(dest, src) + +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 - --no-recursion | tar -xf - -C %s' % (src, src, dst) + check_output(cmd, shell=True, stderr=subprocess.STDOUT) + cmd = 'cd %s; find . -print0 | cpio --null -pdlu %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 |
