diff options
Diffstat (limited to 'buildstream/utils.py')
| -rw-r--r-- | buildstream/utils.py | 120 |
1 files changed, 30 insertions, 90 deletions
diff --git a/buildstream/utils.py b/buildstream/utils.py index 12407ba30..a4e84097b 100644 --- a/buildstream/utils.py +++ b/buildstream/utils.py @@ -34,7 +34,6 @@ import string import subprocess import tempfile import itertools -import functools from contextlib import contextmanager import psutil @@ -767,37 +766,31 @@ def _copy_directories(srcdir, destdir, target): 'directory expected: {}'.format(old_dir)) -@functools.lru_cache(maxsize=64) -def _resolve_symlinks(path): - return os.path.realpath(path) - - -def _ensure_real_directory(root, destpath): - # The realpath in the sandbox may refer to a file outside of the - # sandbox when any of the direcory branches are a symlink to an - # absolute path. - # - # This should not happen as we rely on relative_symlink_target() below - # when staging the actual symlinks which may lead up to this path. - # - destpath_resolved = _resolve_symlinks(destpath) - if not destpath_resolved.startswith(_resolve_symlinks(root)): - raise UtilError('Destination path resolves to a path outside ' + - 'of the staging area\n\n' + - ' Destination path: {}\n'.format(destpath) + - ' Real path: {}'.format(destpath_resolved)) - - # Ensure the real destination path exists before trying to get the mode - # of the real destination path. - # - # It is acceptable that chunks create symlinks inside artifacts which - # refer to non-existing directories, they will be created on demand here - # at staging time. - # - if not os.path.exists(destpath_resolved): - os.makedirs(destpath_resolved) - - return destpath_resolved +# _ensure_real_directory() +# +# Ensure `path` is a real directory and there are no symlink components. +# +# Symlink components are allowed in `root`. +# +def _ensure_real_directory(root, path): + destpath = root + for name in os.path.split(path): + destpath = os.path.join(destpath, name) + try: + deststat = os.lstat(destpath) + if not stat.S_ISDIR(deststat.st_mode): + relpath = destpath[len(root):] + + if stat.S_ISLNK(deststat.st_mode): + filetype = 'symlink' + elif stat.S_ISREG(deststat.st_mode): + filetype = 'regular file' + else: + filetype = 'special file' + + raise UtilError('Destination is a {}, not a directory: {}'.format(filetype, relpath)) + except FileNotFoundError: + os.makedirs(destpath) # _process_list() @@ -836,6 +829,10 @@ def _process_list(srcdir, destdir, filelist, actionfunc, result, srcpath = os.path.join(srcdir, path) destpath = os.path.join(destdir, path) + # Ensure that the parent of the destination path exists without symlink + # components. + _ensure_real_directory(destdir, os.path.dirname(path)) + # Add to the results the list of files written if report_written: result.files_written.append(path) @@ -847,11 +844,6 @@ def _process_list(srcdir, destdir, filelist, actionfunc, result, # The destination directory may not have been created separately permissions.extend(_copy_directories(srcdir, destdir, path)) - # Ensure that broken symlinks to directories have their targets - # created before attempting to stage files across broken - # symlink boundaries - _ensure_real_directory(destdir, os.path.dirname(destpath)) - try: file_stat = os.lstat(srcpath) mode = file_stat.st_mode @@ -865,13 +857,7 @@ def _process_list(srcdir, destdir, filelist, actionfunc, result, if stat.S_ISDIR(mode): # Ensure directory exists in destination - if not os.path.exists(destpath): - _ensure_real_directory(destdir, destpath) - - dest_stat = os.lstat(_resolve_symlinks(destpath)) - if not stat.S_ISDIR(dest_stat.st_mode): - raise UtilError('Destination not a directory. source has {}' - ' destination has {}'.format(srcpath, destpath)) + _ensure_real_directory(destdir, path) permissions.append((destpath, os.stat(srcpath).st_mode)) elif stat.S_ISLNK(mode): @@ -880,7 +866,6 @@ def _process_list(srcdir, destdir, filelist, actionfunc, result, continue target = os.readlink(srcpath) - target = _relative_symlink_target(destdir, destpath, target) os.symlink(target, destpath) elif stat.S_ISREG(mode): @@ -918,51 +903,6 @@ def _process_list(srcdir, destdir, filelist, actionfunc, result, os.chmod(d, perms) -# _relative_symlink_target() -# -# Fetches a relative path for symlink with an absolute target -# -# @root: The staging area root location -# @symlink: Location of the symlink in staging area (including the root path) -# @target: The symbolic link target, which may be an absolute path -# -# If @target is an absolute path, a relative path from the symbolic link -# location will be returned, otherwise if @target is a relative path, it will -# be returned unchanged. -# -# Using relative symlinks helps to keep the target self contained when staging -# files onto the target. -# -def _relative_symlink_target(root, symlink, target): - - if os.path.isabs(target): - # First fix the input a little, the symlink itself must not have a - # trailing slash, otherwise we fail to remove the symlink filename - # from its directory components in os.path.split() - # - # The absolute target filename must have its leading separator - # removed, otherwise os.path.join() will discard the prefix - symlink = symlink.rstrip(os.path.sep) - target = target.lstrip(os.path.sep) - - # We want a relative path from the directory in which symlink - # is located, not from the symlink itself. - symlinkdir, _ = os.path.split(_resolve_symlinks(symlink)) - - # Create a full path to the target, including the leading staging - # directory - fulltarget = os.path.join(_resolve_symlinks(root), target) - - # now get the relative path from the directory where the symlink - # is located within the staging root, to the target within the same - # staging root - newtarget = os.path.relpath(fulltarget, symlinkdir) - - return newtarget - else: - return target - - # _set_deterministic_user() # # Set the uid/gid for every file in a directory tree to the process' |