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 replace_absolute_symlinks(basedir, d): """ Walk basedir looking for absolute symlinks and replacing them with relative ones. The absolute links are assumed to be relative to basedir (compared to make_relative_symlink above which tries to compute common ancestors using pattern matching instead) """ for walkroot, dirs, files in os.walk(basedir): for file in files + dirs: path = os.path.join(walkroot, file) if not os.path.islink(path): continue link = os.readlink(path) if not os.path.isabs(link): continue walkdir = os.path.dirname(path.rpartition(basedir)[2]) base = os.path.relpath(link, walkdir) bb.debug(2, "Replacing absolute path %s with relative path %s" % (link, base)) 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"), 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 --xattrs --xattrs-include='*' -cf - -S -C %s -p . | tar --xattrs --xattrs-include='*' -xf - -C %s" % (src, dst) subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT) def copyhardlinktree(src, dst): """Make a tree of hard links 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 --xattrs --xattrs-include='*' -cf - -S -C %s -p --no-recursion --files-from - | tar --xattrs --xattrs-include='*' -xhf - -C %s" % (src, src, dst) subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT) source = '' if os.path.isdir(src): if len(glob.glob('%s/.??*' % src)) > 0: source = './.??* ' source += './*' s_dir = src else: source = src s_dir = os.getcwd() cmd = 'cp -afl --preserve=xattr %s %s' % (source, os.path.realpath(dst)) subprocess.check_output(cmd, shell=True, cwd=s_dir, stderr=subprocess.STDOUT) else: copytree(src, dst) def copyhardlink(src, dst): """Make a hard link when possible, otherwise copy.""" # We need to stat the destination directory as the destination file probably # doesn't exist yet. dstdir = os.path.dirname(dst) if os.stat(src).st_dev == os.stat(dstdir).st_dev: os.link(src, dst) else: shutil.copy(src, dst) def remove(path, recurse=True): """ Equivalent to rm -f or rm -rf NOTE: be careful about passing paths that may contain filenames with wildcards in them (as opposed to passing an actual wildcarded path) - since we use glob.glob() to expand the path. Filenames containing square brackets are particularly problematic since the they may not actually expand to match the original filename. """ 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 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 def is_path_parent(possible_parent, *paths): """ Return True if a path is the parent of another, False otherwise. Multiple paths to test can be specified in which case all specified test paths must be under the parent in order to return True. """ def abs_path_trailing(pth): pth_abs = os.path.abspath(pth) if not pth_abs.endswith(os.sep): pth_abs += os.sep return pth_abs possible_parent_abs = abs_path_trailing(possible_parent) if not paths: return False for path in paths: path_abs = abs_path_trailing(path) if not path_abs.startswith(possible_parent_abs): return False return True def which_wild(pathname, path=None, mode=os.F_OK, *, reverse=False, candidates=False): """Search a search path for pathname, supporting wildcards. Return all paths in the specific search path matching the wildcard pattern in pathname, returning only the first encountered for each file. If candidates is True, information on all potential candidate paths are included. """ paths = (path or os.environ.get('PATH', os.defpath)).split(':') if reverse: paths.reverse() seen, files = set(), [] for index, element in enumerate(paths): if not os.path.isabs(element): element = os.path.abspath(element) candidate = os.path.join(element, pathname) globbed = glob.glob(candidate) if globbed: for found_path in sorted(globbed): if not os.access(found_path, mode): continue rel = os.path.relpath(found_path, element) if rel not in seen: seen.add(rel) if candidates: files.append((found_path, [os.path.join(p, rel) for p in paths[:index+1]])) else: files.append(found_path) return files