# SPDX-License-Identifier: GPL-3.0-or-later
# Copyright (c) 2008-2026 Andrew Ziem.
#
# This work is licensed under the terms of the GNU GPL, version 3 or
# later.  See the COPYING file in the top-level directory.

"""
File-related utilities
"""

# standard imports
import contextlib
import errno
import glob
import json
import locale
import logging
import os
import os.path
import re
import sqlite3
import stat
import subprocess
import sys
import time
import urllib.parse
import urllib.request
from os import walk
from pathlib import Path

# local imports
import bleachbit
from bleachbit.Language import get_text as _
from bleachbit.Wipe import wipe_contents, wipe_name


logger = logging.getLogger(__name__)

if 'nt' == os.name:
    # pylint: disable=import-error, no-name-in-module
    from pywintypes import error as pywinerror
    import win32file
    from win32file import GetFileAttributesW, SetFileAttributesW
    from win32con import FILE_ATTRIBUTE_READONLY

    # pylint: disable=ungrouped-imports
    import bleachbit.Windows
    os_path_islink = os.path.islink
    os.path.islink = lambda path: os_path_islink(
        path) or bleachbit.Windows.is_junction(path)

if 'posix' == os.name:
    # pylint: disable=redefined-builtin
    from bleachbit.General import WindowsError
    # pylint: disable=invalid-name
    pywinerror = WindowsError


def _remove_windows_readonly(path):
    """Clear Windows read-only attribute so deletion/wiping succeeds

    Returns True if file was read-only and was cleared. Otherwise, False.
    """
    if os.name != 'nt':
        return False
    try:
        attrs = GetFileAttributesW(path)
    except pywinerror:
        return False
    if attrs & FILE_ATTRIBUTE_READONLY:
        SetFileAttributesW(path, attrs & ~FILE_ATTRIBUTE_READONLY)
        return True
    return False


def open_files_linux():
    """Return iterator of open files on Linux"""
    return glob.iglob("/proc/*/fd/*")


def get_filesystem_type(path):
    """Get file system type from the given path

    path: directory path

    Return value:
    A tuple of (file_system_type, device_name)
    file_system_type: vfat, ntfs, etc.
    device_name: C:, D:, etc.

    File system types seen
    * On Linux: btrfs,ext4, vfat, squashfs
    * On Windows: NTFS, FAT32, CDFS
    """
    try:
        # pylint: disable=import-outside-toplevel
        import psutil
    except ImportError:
        logger.warning(
            'To get the file system type from the given path, you need to install psutil package')
        return ("unknown", "none")

    path_obj = Path(path)
    if os.name == 'nt':
        if len(path) == 2 and path[1] == ':':
            path_obj = Path(path + '\\')

    # Get all partitions with Path objects as keys
    partitions = {}
    for partition in psutil.disk_partitions():
        mount_path = Path(partition.mountpoint)
        partitions[mount_path] = (partition.fstype, partition.device)

    # Exact match
    for mount_path, fs_info in partitions.items():
        if path_obj == mount_path:
            return fs_info

    # Try parent paths
    current = path_obj
    while current.parent != current:  # Stop at root
        current = current.parent
        for mount_path, fs_info in partitions.items():
            if current == mount_path:
                return fs_info

    return ("unknown", "none")


def open_files_lsof(run_lsof=None):
    """Return iterator of open files using lsof"""
    if run_lsof is None:
        def run_lsof():
            return subprocess.check_output(["lsof", "-Fn", "-n"])
    for f in run_lsof().split("\n"):
        if f.startswith("n/"):
            yield f[1:]  # Drop lsof's "n"


def open_files():
    """Return iterator of open files"""
    if sys.platform == 'linux':
        files = open_files_linux()
    elif 'darwin' == sys.platform or sys.platform.startswith('freebsd'):
        files = open_files_lsof()
    else:
        raise RuntimeError('unsupported platform for open_files()')
    for filename in files:
        try:
            target = os.path.realpath(filename)
        except TypeError:
            # happens, for example, when link points to
            # '/etc/password\x00 (deleted)'
            continue
        except PermissionError:
            # /proc/###/fd/0 with systemd
            # https://github.com/bleachbit/bleachbit/issues/1515
            continue
        else:
            yield target


class OpenFiles:

    """Cached way to determine whether a file is open by active process"""

    def __init__(self):
        self.last_scan_time = None
        self.files = []

    def file_qualifies(self, filename):
        """Return boolean whether filename qualifies to enter cache (check \
        against blacklist)"""
        return not filename.startswith("/dev") and \
            not filename.startswith("/proc")

    def scan(self):
        """Update cache"""
        self.last_scan_time = time.time()
        self.files = []
        for filename in open_files():
            if self.file_qualifies(filename):
                self.files.append(filename)

    def is_open(self, filename):
        """Return boolean whether filename is open by running process"""
        if self.last_scan_time is None or (time.time() - self.last_scan_time) > 10:
            self.scan()
        return os.path.realpath(filename) in self.files


def bytes_to_human(bytes_i):
    # type: (int) -> str
    """Display a file size in human terms (megabytes, etc.) using preferred standard (SI or IEC)"""

    if bytes_i < 0:
        return '-' + bytes_to_human(-bytes_i)

    from bleachbit.Options import options
    if options.get('units_iec'):
        prefixes = ['', 'Ki', 'Mi', 'Gi', 'Ti', 'Pi']
        base = 1024.0
    else:
        prefixes = ['', 'k', 'M', 'G', 'T', 'P']
        base = 1000.0

    assert isinstance(bytes_i, int)

    if 0 == bytes_i:
        return '0B'

    if bytes_i >= base ** 3:
        decimals = 2
    elif bytes_i >= base:
        decimals = 1
    else:
        decimals = 0

    for _exponent, prefix in enumerate(prefixes):
        if bytes_i < base:
            abbrev = round(bytes_i, decimals)
            suf = prefix
            return locale.str(abbrev) + suf + 'B'
        bytes_i /= base
    return 'A lot.'


def children_in_directory(top, list_directories=False):
    """Iterate files and, optionally, subdirectories in directory

    Directories are returned after children to avoid trying to delete
    a non-empty directory.
    """
    if isinstance(top, tuple):
        for top_ in top:
            yield from children_in_directory(top_, list_directories)
        return

    def _normalized_prefix(path):
        norm_path = os.path.normpath(path)
        if os.name == 'nt':
            norm_path = norm_path.lower()
        if not norm_path.endswith(os.sep):
            norm_path += os.sep
        return norm_path

    pending_dirs = [] if list_directories else None

    for (dirpath, dirnames, filenames) in walk(top, topdown=True, followlinks=False):
        if 'nt' == os.name and dirnames:
            # Avoid traversing Windows symlinks or junctions.
            link_dirnames = []
            for dirname in list(dirnames):
                if os.path.islink(os.path.join(dirpath, dirname)):
                    link_dirnames.append(dirname)
                    dirnames.remove(dirname)
            if list_directories:
                for dirname in link_dirnames:
                    yield os.path.join(dirpath, dirname)
        if list_directories:
            for dirname in dirnames:
                full_path = os.path.join(dirpath, dirname)
                pending_dirs.append((full_path, _normalized_prefix(full_path)))
        for filename in filenames:
            yield os.path.join(dirpath, filename)

    if list_directories:
        pending_dirs.sort(key=lambda x: len(x[1]))
        while pending_dirs:
            yield pending_dirs.pop()[0]


def clean_ini(path, section, parameter):
    """Delete sections and parameters (aka option) in the file

    Comments are not preserved.
    """

    def write(parser, ini_file):
        """
        Reimplementation of the original RowConfigParser write function.

        This function is 99% same as its origin. The only change is
        removing a cast to str. This is needed to handle unicode chars.
        """
        if parser._defaults:
            ini_file.write("[DEFAULT]\n")
            for (key, value) in parser._defaults.items():
                value_str = str(value).replace('\n', '\n\t')
                ini_file.write(f"{key} = {value_str}\n")
            ini_file.write("\n")
        for section in parser._sections:
            ini_file.write(f"[{section}]\n")
            for (key, value) in parser._sections[section].items():
                if key == "__name__":
                    continue
                if (value is not None) or (parser._optcre == parser.OPTCRE):
                    # The line below is the only changed line of the original function.
                    # This is the original line for reference:
                    # key = " = ".join((key, str(value).replace('\n', '\n\t')))
                    key = " = ".join((key, value.replace('\n', '\n\t')))
                ini_file.write(f"{key}\n")
            ini_file.write("\n")

    encoding = detect_encoding(path) or 'utf_8_sig'

    # read file to parser
    config = bleachbit.RawConfigParser(delimiters='=')
    config.optionxform = lambda option: option
    config.write = write
    with open(path, 'r', encoding=encoding) as fp:
        config.read_file(fp)

    # change file
    changed = False
    if config.has_section(section):
        if parameter is None:
            changed = True
            config.remove_section(section)
        elif config.has_option(section, parameter):
            changed = True
            config.remove_option(section, parameter)

    # write file
    if changed:
        from bleachbit.Options import options
        fp.close()
        if options.get('shred'):
            delete(path, True)
        with open(path, 'w', encoding=encoding, newline='') as fp:
            config.write(config, fp)


def clean_json(path, target):
    """Delete key in the JSON file"""
    changed = False
    targets = target.split('/')

    # read file to parser
    with open(path, 'r', encoding='utf-8-sig') as f:
        js = json.load(f)

    # change file
    pos = js
    while True:
        new_target = targets.pop(0)
        if not isinstance(pos, dict):
            break
        if new_target in pos and len(targets) > 0:
            # descend
            pos = pos[new_target]
        elif new_target in pos:
            # delete terminal target
            changed = True
            del pos[new_target]
        else:
            # target not found
            break
        if 0 == len(targets):
            # target not found
            break

    if changed:
        from bleachbit.Options import options
        if options.get('shred'):
            delete(path, True)
        # write file
        with open(path, 'w', encoding='utf-8') as f:
            json.dump(js, f)


def _truncate_locked_file(path):
    """Best-effort truncate of a locked file (Windows).

    Returns True if truncation succeeded, False otherwise.
    Shared locks allow truncation, exclusive locks prevent it.
    """
    try:
        with open(path, 'r+b') as handle:
            handle.truncate(0)
        return True
    except (OSError, PermissionError):
        logger.debug("Unable to truncate locked file %s", path)
        return False


def delete_file(path, shred):
    """"Delete a file

    - File must exist.
    - Not for use with directories.
    - Does not check the user's preferences.

    Returns True.
    """
    # wipe contents
    if shred and not is_hard_link(path):
        try:
            wipe_contents(path)
        except pywinerror as e:  # pylint: disable=possibly-used-before-assignment
            # 2 = The system cannot find the file specified.
            # This can happen with a broken symlink
            # https://github.com/bleachbit/bleachbit/issues/195
            if 2 != e.winerror:
                raise
            # If a broken symlink, try os.remove() below.
        except IOError as e:
            # permission denied (13) happens shredding MSIE 8 on Windows 7
            logger.debug("IOError #%s shredding '%s'",
                         e.errno, path)
    if shred:
        # wipe name
        os.remove(wipe_name(path))
        return True
    # Code below is shred == False
    try:
        os.remove(path)
    except PermissionError as e:
        if os.name == 'nt' and hasattr(e, 'winerror'):
            if e.winerror == 32:
                # File is locked, try to truncate it first
                _truncate_locked_file(path)
                # Command.py watches for this exception.
                raise WindowsError(e.errno, e.strerror,
                                   e.filename, e.winerror) from e
            if e.errno == errno.EACCES and e.winerror == 5 and \
                    _remove_windows_readonly(path):
                # If read-only attribute was removed, try again.
                os.remove(path)
                return True
        raise
    except WindowsError as e:
        if e.winerror == 32:
            # File is locked, try to truncate it first
            _truncate_locked_file(path)
        raise
    return True


def delete(path, shred=False, ignore_missing=False, allow_shred=True):
    """Delete path that is either file, directory, link or FIFO.

       If shred is enabled as a function parameter or the BleachBit global
       parameter, the path will be shredded unless allow_shred = False.

       All links are removed without following the link. This includes:
       * Linux symlink
       * Windows symlink (soft link)
       * Windows hard link
       * Windows junction
       * Windows .lnk files

       Returns True if the path was deleted, False otherwise.
    """
    from bleachbit.Options import options
    is_special = False
    path = extended_path(path)
    do_shred = allow_shred and (shred or options.get('shred'))
    if not os.path.lexists(path):
        if ignore_missing:
            return False
        raise OSError(2, 'No such file or directory', path)
    if 'posix' == os.name:
        # With certain (relatively rare) files on Windows os.lstat()
        # may return Access Denied
        mode = os.lstat(path)[stat.ST_MODE]
        is_special = stat.S_ISFIFO(mode) or stat.S_ISLNK(mode)
    if is_special:
        os.remove(path)
        return True
    if os.path.isdir(path):
        delpath = path
        # TRANSLATORS: Log message where %s is the pathname.
        not_empty_msg = _("Directory is not empty: %s")
        if do_shred:
            if not is_dir_empty(path):
                # Avoid renaming non-empty directory like
                # https://github.com/bleachbit/bleachbit/issues/783
                logger.info(not_empty_msg, path)
                return False
            delpath = wipe_name(path)
        try:
            os.rmdir(delpath)
        except OSError as e:
            # [Errno 39] Directory not empty
            # https://bugs.launchpad.net/bleachbit/+bug/1012930
            if errno.ENOTEMPTY == e.errno:
                logger.info(not_empty_msg, path)
                return False
            elif errno.EBUSY == e.errno:
                if os.name == 'posix' and os.path.ismount(path):
                    # TRANSLATORS: Log message where %s is the pathname.
                    logger.info(_("Skipping mount point: %s"), path)
                else:
                    # TRANSLATORS: Log message where %s is the pathname.
                    logger.info(_("Device or resource is busy: %s"), path)
                return False
            elif os.name == 'nt' and errno.EACCES == e.errno:
                # On Windows, read-only directories cause Access Denied
                if _remove_windows_readonly(delpath):
                    os.rmdir(delpath)
                else:
                    raise
            else:
                raise
        except WindowsError as e:
            # WindowsError: [Error 145] The directory is not empty:
            # 'C:\\Documents and Settings\\username\\Local Settings\\Temp\\NAILogs'
            # Error 145 may happen if the files are scheduled for deletion
            # during reboot.
            if 145 == e.winerror:
                logger.info(not_empty_msg, path)
                return False
            else:
                raise
        return True
    elif os.path.isfile(path):
        delete_file(path, do_shred)
        return True
    elif os.path.islink(path):
        os.remove(path)
        return True
    else:
        # TRANSLATORS: Log message where %s is the pathname.
        logger.info(_("Special file type cannot be deleted: %s"), path)
        return False


def detect_encoding(fn):
    """Detect the encoding of the file"""
    try:
        # pylint: disable=import-outside-toplevel
        import chardet
    except ImportError:
        logger.warning(
            'chardet module is not available to detect character encoding')
        return None

    with open(fn, 'rb') as f:
        detector = chardet.universaldetector.UniversalDetector()
        for line in f.readlines():
            detector.feed(line)
            if detector.done:
                break
        detector.close()
    return detector.result['encoding']


def ego_owner(filename):
    """Return whether current user owns the file

    POSIX only"""
    assert 'posix' == os.name
    # pylint: disable=no-member
    return os.lstat(filename).st_uid == os.getuid()


def exists_in_path(filename):
    """Returns boolean whether the filename exists in the path"""
    delimiter = ':'
    if 'nt' == os.name:
        delimiter = ';'
    path_env = os.getenv('PATH')
    if not path_env:
        return False
    assert not os.path.isabs(filename)
    for dirname in path_env.split(delimiter):
        if os.path.exists(os.path.join(dirname, filename)):
            return True
    return False


def exe_exists(pathname):
    """Returns boolean whether executable exists"""
    if os.path.isabs(pathname):
        return os.path.exists(pathname)
    else:
        return exists_in_path(pathname)


def execute_sqlite3(path, cmds):
    """Execute SQL commands on SQLite database

    Args:
        path (str): Path to the SQLite database file
        cmds (str): SQL commands to execute, separated by semicolons

    Raises:
        sqlite3.OperationalError: If there's an error executing the SQL commands
        sqlite3.DatabaseError: If there's a database-related error

    Returns:
        None
    """
    from bleachbit.Options import options
    assert isinstance(path, str)
    assert isinstance(cmds, str)
    with contextlib.closing(sqlite3.connect(path)) as conn:
        # overwrites deleted content with zeros
        # https://www.sqlite.org/pragma.html#pragma_secure_delete
        if options.get('shred'):
            conn.execute('PRAGMA secure_delete=ON')
            assert conn.execute('PRAGMA secure_delete').fetchone()[0] == 1

        for cmd in cmds.split(';'):
            try:
                conn.execute(cmd)
            except sqlite3.OperationalError as exc:
                if str(exc).find('no such function: ') >= 0:
                    # fixme: determine why randomblob and zeroblob are not
                    # available
                    logger.exception(exc.message)
                else:
                    raise sqlite3.OperationalError(f'{exc}: {path}')
            except sqlite3.DatabaseError as exc:
                raise sqlite3.DatabaseError(f'{exc}: {path}')

        conn.commit()

    bleachbit.General.gc_collect()


def expand_glob_join(pathname1, pathname2):
    """Join pathname1 and pathname1, expand pathname, glob, and return as list"""
    pathname3 = os.path.expanduser(os.path.expandvars(
        os.path.join(pathname1, pathname2)))
    ret = [pathname4 for pathname4 in glob.iglob(pathname3)]
    return ret


def extended_path(path):
    r"""Return the extended Windows pathname

    example: c:\foo\bar.txt to \\?\c:\foo\bar.txt

    The path is returned unchanged if:
    * Path was already extended
    * Path is a sysnative path
    * System is not Windows
    """
    # Do not extend the Sysnative paths because on some systems there are
    # problems with path resolution. For example:
    # https://github.com/bleachbit/bleachbit/issues/1574.
    if 'nt' == os.name and 'Sysnative' not in path.split(os.sep):
        if path.startswith(r'\\?'):
            return path
        if path.startswith(r'\\'):
            return '\\\\?\\unc\\' + path[2:]
        return '\\\\?\\' + path
    return path


def extended_path_undo(path):
    r"""Undo extended path

    For example: \\c:\foo\bar.txt -> c:\foo\bar.txt
    """
    if 'nt' == os.name:
        if path.startswith(r'\\?\unc'):
            return '\\' + path[7:]
        if path.startswith(r'\\?'):
            return path[4:]
    return path


def free_space(pathname):
    """Return free space in bytes

    pathname may be any directory within a valid file system.

    POSIX systems may reserve space for the root user, and this function
    returns the amount available to the current user for accurate
    estimation of completion time in wipe_path().
    """
    if 'nt' == os.name:
        # pylint: disable=import-error,import-outside-toplevel
        import psutil
        return psutil.disk_usage(pathname).free
    assert 'posix' == os.name
    # pylint: disable=no-member
    mystat = os.statvfs(pathname)
    if os.getuid() == 0:
        # root
        return mystat.f_bfree * mystat.f_bsize
    # non-root
    return mystat.f_bavail * mystat.f_bsize


def getsize(path):
    """Return the actual file size considering spare files
       and symlinks"""
    if 'posix' == os.name:
        try:
            __stat = os.lstat(path)
        except OSError as e:
            # OSError: [Errno 13] Permission denied
            # can happen when a regular user is trying to find the size of /var/log/hp/tmp
            # where /var/log/hp is 0774 and /var/log/hp/tmp is 1774
            if errno.EACCES == e.errno:
                return 0
            raise
        return __stat.st_blocks * 512
    if 'nt' == os.name:
        # On rare files os.path.getsize() returns access denied, so first
        # try FindFilesW.
        # Also, apply prefix to use extended-length paths to support longer
        # filenames.
        try:
            # pylint: disable=c-extension-no-member
            finddata = win32file.FindFilesW(extended_path(path))
        except pywinerror as e:
            if e.winerror == 3:  # 3 = The system cannot find the path specified.
                raise OSError(errno.ENOENT, e.strerror, path)
            raise e
        if not finddata:
            # FindFilesW does not work for directories, so fall back to
            # getsize()
            return os.path.getsize(path)
        else:
            size = (finddata[0][4] * (0xffffffff + 1)) + finddata[0][5]
            return size
    return os.path.getsize(path)


def getsizedir(path):
    """Return the size of the contents of a directory"""
    total_bytes = sum(
        getsize(node)
        for node in children_in_directory(path, list_directories=False)
    )
    return total_bytes


def globex(pathname, regex):
    """Yield a list of files with pathname and filter by regex"""
    if isinstance(pathname, tuple):
        for singleglob in pathname:
            yield from globex(singleglob, regex)
    else:
        for path in glob.iglob(pathname):
            if re.search(regex, path):
                yield path


def guess_overwrite_paths():
    """Guess which partitions to overwrite (to hide deleted files)"""
    # In case overwriting leaves large files, placing them in
    # ~/.config makes it easy to find them and clean them.
    ret = []
    if 'posix' == os.name:
        home = os.path.expanduser('~/.cache')
        if not os.path.exists(home):
            home = os.path.expanduser("~")
        ret.append(home)
        # Debian on Docker did not have /tmp
        if os.path.exists('/tmp'):
            if not same_partition(home, '/tmp/'):
                ret.append('/tmp')
    elif 'nt' == os.name:
        localtmp = os.path.expandvars('$TMP')
        if not os.path.exists(localtmp):
            logger.warning(
                # TRANSLATORS: This is a warning log message. %s is the directory path.
                _("The environment variable TMP refers to a directory that does not exist: %s"), localtmp)
            localtmp = None
        for drive in bleachbit.Windows.get_fixed_drives():
            if localtmp and same_partition(localtmp, drive):
                ret.append(localtmp)
            else:
                ret.append(drive)
    else:
        raise NotImplementedError('Unsupported OS in guess_overwrite_paths')
    return ret


def human_to_bytes(human, hformat='si'):
    """Convert a string like 10.2GB into bytes.  By
    default use SI standard (base 10).  The format of the
    GNU command 'du' (base 2) also supported."""

    if 'si' == hformat:
        base = 1000
        suffixes = 'kMGTE'
    elif 'du' == hformat:
        base = 1024
        suffixes = 'KMGTE'
    else:
        raise ValueError(f"Invalid format: '{hformat}'")
    matches = re.match(r'^(\d+(?:\.\d+)?) ?([' + suffixes + ']?)B?$', human)
    if matches is None:
        raise ValueError(f"Invalid input for '{human}' (hformat='{hformat}')")
    (amount, suffix) = matches.groups()

    if '' == suffix:
        exponent = 0
    else:
        exponent = suffixes.find(suffix) + 1
    return int(float(amount) * base**exponent)


def is_dir_empty(dirname):
    """Returns boolean whether directory is empty.

    It assumes the path exists and is a directory.
    """
    with os.scandir(dirname) as it:
        for _entry in it:
            return False
    return True


def is_hard_link(path):
    """Check if a file is a hard link."""
    return os.path.isfile(path) and os.stat(path).st_nlink > 1


def is_normal_directory(path):
    """Check whether path is a non-link directory

    Returns False if:
        - path does not exist
        - path is a file
        - path is a reparse point
    Returns True if a normal directory
    """

    try:
        st = os.stat(path, follow_symlinks=False)
        is_dir = stat.S_ISDIR(st.st_mode)
        is_reparse = getattr(st, 'st_reparse_tag', 0) != 0
        return is_dir and not is_reparse
    except (OSError, ValueError):
        return False


def listdir(directory):
    """Return full path of files in directory.

    Path may be a tuple of directories."""

    if isinstance(directory, tuple):
        for dirname in directory:
            yield from listdir(dirname)
        return
    dirname = os.path.expanduser(directory)
    if not os.path.lexists(dirname):
        return
    for filename in os.listdir(dirname):
        yield os.path.join(dirname, filename)


def same_partition(dir1, dir2):
    """Are both directories on the same partition?"""
    if 'nt' == os.name:
        try:
            return free_space(dir1) == free_space(dir2)
        except OSError as e:
            # psutil.disk_usage() raises OSError (with .winerror on Windows).
            # 5 = access denied: Microsoft Office 2010 Starter Edition has a
            #     virtual drive that gives access denied.
            #     https://bugs.launchpad.net/bleachbit/+bug/1372179
            #     https://bugs.launchpad.net/bleachbit/+bug/1474848
            #     https://github.com/az0/bleachbit/issues/27
            # 1326 = logon failure: disconnected network drive.
            if getattr(e, 'winerror', None) in (5, 1326):
                return dir1[0] == dir2[0]
            raise
    # pylint: disable=no-member
    stat1 = os.statvfs(dir1)
    stat2 = os.statvfs(dir2)
    return stat1[stat.ST_DEV] == stat2[stat.ST_DEV]


def truncate_f(f):
    """Truncate the file object"""
    try:
        f.truncate(0)
        f.flush()
        os.fsync(f.fileno())
    except OSError as e:
        if e.errno != errno.ENOSPC:
            raise


def uris_to_paths(file_uris):
    """Return a list of paths from text/uri-list"""
    assert isinstance(file_uris, (tuple, list))
    file_paths = []
    for file_uri in file_uris:
        if not file_uri:
            # ignore blank
            continue
        parsed_uri = urllib.parse.urlparse(file_uri)
        if parsed_uri.scheme == 'file':
            file_path = urllib.request.url2pathname(parsed_uri.path)
            if file_path[2] == ':':
                # remove front slash for Windows-style path
                file_path = file_path[1:]
            file_paths.append(file_path)
        else:
            logger.warning('Unsupported scheme: %s', file_uri)
    return file_paths


def whitelisted_posix(path, check_realpath=True):
    """Check whether this POSIX path is whitelisted"""
    from bleachbit.Options import options
    if check_realpath and os.path.islink(path):
        # also check the link name
        if whitelisted_posix(path, False):
            return True
        # resolve symlink
        path = os.path.realpath(path)
    for pathname in options.get_whitelist_paths():
        if pathname[0] == 'file' and path == pathname[1]:
            return True
        if pathname[0] == 'folder':
            if path == pathname[1]:
                return True
            if path.startswith(pathname[1] + os.sep):
                return True
    return False


def whitelisted_windows(path):
    """Check whether this Windows path is whitelisted"""
    from bleachbit.Options import options
    for pathname in options.get_whitelist_paths():
        # Windows is case insensitive
        if pathname[0] == 'file' and path.lower() == pathname[1].lower():
            return True
        if pathname[0] == 'folder':
            if path.lower() == pathname[1].lower():
                return True
            if path.lower().startswith(pathname[1].lower() + os.sep):
                return True
            # Simple drive letter like C:\ matches everything below
            if len(pathname[1]) == 3 and path.lower().startswith(pathname[1].lower()):
                return True
    return False


if 'nt' == os.name:
    whitelisted = whitelisted_windows
else:
    whitelisted = whitelisted_posix


def vacuum_sqlite3(path):
    """Vacuum SQLite database"""
    execute_sqlite3(path, 'vacuum')


openfiles = OpenFiles()
