panda.net.ftp.parser.UnixFTPEntryParser Maven / Gradle / Ivy
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package panda.net.ftp.parser;
import java.text.ParseException;
import java.util.List;
import java.util.ListIterator;
import panda.net.ftp.FTPClientConfig;
import panda.net.ftp.FTPFile;
/**
* Implementation FTPFileEntryParser and FTPFileListParser for standard Unix Systems. This class is
* based on the logic of Daniel Savarese's DefaultFTPListParser, but adapted to use regular
* expressions and to fit the new FTPFileEntryParser interface.
*
* @version $Id: UnixFTPEntryParser.java 1697290 2015-08-24 00:33:56Z sebb $
* @see panda.net.ftp.FTPFileEntryParser FTPFileEntryParser (for usage instructions)
*/
public class UnixFTPEntryParser extends ConfigurableFTPFileEntryParserImpl {
static final String DEFAULT_DATE_FORMAT = "MMM d yyyy"; // Nov 9 2001
static final String DEFAULT_RECENT_DATE_FORMAT = "MMM d HH:mm"; // Nov 9 20:06
static final String NUMERIC_DATE_FORMAT = "yyyy-MM-dd HH:mm"; // 2001-11-09 20:06
/**
* Some Linux distributions are now shipping an FTP server which formats file listing dates in
* an all-numeric format: "yyyy-MM-dd HH:mm. This is a very welcome development,
* and hopefully it will soon become the standard. However, since it is so new, for now, and
* possibly forever, we merely accomodate it, but do not make it the default.
*
* For now end users may specify this format only via
* UnixFTPEntryParser(FTPClientConfig). Steve Cohen - 2005-04-17
*/
public static final FTPClientConfig NUMERIC_DATE_CONFIG = new FTPClientConfig(FTPClientConfig.SYST_UNIX,
NUMERIC_DATE_FORMAT, null, null, null, null);
/**
* this is the regular expression used by this parser. Permissions: r the file is readable w the
* file is writable x the file is executable - the indicated permission is not granted L
* mandatory locking occurs during access (the set-group-ID bit is on and the group execution
* bit is off) s the set-user-ID or set-group-ID bit is on, and the corresponding user or group
* execution bit is also on S undefined bit-state (the set-user-ID bit is on and the user
* execution bit is off) t the 1000 (octal) bit, or sticky bit, is on [see chmod(1)], and
* execution is on T the 1000 bit is turned on, and execution is off (undefined bit- state) e
* z/OS external link bit Final letter may be appended: + file has extended security attributes
* (e.g. ACL) Note: local listings on MacOSX also use '@'; this is not allowed for here as does
* not appear to be shown by FTP servers {@code @} file has extended attributes
*/
private static final String REGEX = "([bcdelfmpSs-])" // file type
+ "(((r|-)(w|-)([xsStTL-]))((r|-)(w|-)([xsStTL-]))((r|-)(w|-)([xsStTL-])))\\+?" // permissions
+ "\\s*" // separator TODO why allow it to be omitted??
+ "(\\d+)" // link count
+ "\\s+" // separator
+ "(?:(\\S+(?:\\s\\S+)*?)\\s+)?" // owner name (optional spaces)
+ "(?:(\\S+(?:\\s\\S+)*)\\s+)?" // group name (optional spaces)
+ "(\\d+(?:,\\s*\\d+)?)" // size or n,m
+ "\\s+" // separator
/*
* numeric or standard format date: yyyy-mm-dd (expecting hh:mm to follow) MMM [d]d [d]d
* MMM N.B. use non-space for MMM to allow for languages such as German which use
* diacritics (e.g. umlaut) in some abbreviations.
*/
+ "((?:\\d+[-/]\\d+[-/]\\d+)|(?:\\S{3}\\s+\\d{1,2})|(?:\\d{1,2}\\s+\\S{3}))"
+ "\\s+" // separator
/*
* year (for non-recent standard format) - yyyy or time (for numeric or recent standard
* format) [h]h:mm
*/
+ "(\\d+(?::\\d+)?)" // (20)
+ "\\s" // separator
+ "(.*)"; // the rest (21)
// if true, leading spaces are trimmed from file names
// this was the case for the original implementation
private final boolean trimLeadingSpaces;
/**
* The default constructor for a UnixFTPEntryParser object.
*
* @exception IllegalArgumentException Thrown if the regular expression is unparseable. Should
* not be seen under normal conditions. It it is seen, this is a sign that
* REGEX is not a valid regular expression.
*/
public UnixFTPEntryParser() {
this(null);
}
/**
* This constructor allows the creation of a UnixFTPEntryParser object with something other than
* the default configuration.
*
* @param config The {@link FTPClientConfig configuration} object used to configure this parser.
* @exception IllegalArgumentException Thrown if the regular expression is unparseable. Should
* not be seen under normal conditions. It it is seen, this is a sign that
* REGEX is not a valid regular expression.
*/
public UnixFTPEntryParser(FTPClientConfig config) {
this(config, false);
}
/**
* This constructor allows the creation of a UnixFTPEntryParser object with something other than
* the default configuration.
*
* @param config The {@link FTPClientConfig configuration} object used to configure this parser.
* @param trimLeadingSpaces if {@code true}, trim leading spaces from file names
* @exception IllegalArgumentException Thrown if the regular expression is unparseable. Should
* not be seen under normal conditions. It it is seen, this is a sign that
* REGEX is not a valid regular expression.
*/
public UnixFTPEntryParser(FTPClientConfig config, boolean trimLeadingSpaces) {
super(REGEX);
configure(config);
this.trimLeadingSpaces = trimLeadingSpaces;
}
/**
* Preparse the list to discard "total nnn" lines
*/
@Override
public List preParse(List original) {
ListIterator iter = original.listIterator();
while (iter.hasNext()) {
String entry = iter.next();
if (entry.matches("^total \\d+$")) { // NET-389
iter.remove();
}
}
return original;
}
/**
* Parses a line of a unix (standard) FTP server file listing and converts it into a usable
* format in the form of an FTPFile instance. If the file listing line doesn't
* describe a file, null is returned, otherwise a FTPFile instance
* representing the files in the directory is returned.
*
* @param entry A line of text from the file listing
* @return An FTPFile instance corresponding to the supplied entry
*/
// @Override
public FTPFile parseFTPEntry(String entry) {
FTPFile file = new FTPFile();
file.setRawListing(entry);
int type;
boolean isDevice = false;
if (matches(entry)) {
String typeStr = group(1);
String hardLinkCount = group(15);
String usr = group(16);
String grp = group(17);
String filesize = group(18);
String datestr = group(19) + " " + group(20);
String name = group(21);
if (trimLeadingSpaces) {
name = name.replaceFirst("^\\s+", "");
}
try {
file.setTimestamp(super.parseTimestamp(datestr));
}
catch (ParseException e) {
// intentionally do nothing
}
// A 'whiteout' file is an ARTIFICIAL entry in any of several types of
// 'translucent' filesystems, of which a 'union' filesystem is one.
// bcdelfmpSs-
switch (typeStr.charAt(0)) {
case 'd':
type = FTPFile.DIRECTORY_TYPE;
break;
case 'e': // NET-39 => z/OS external link
type = FTPFile.SYMBOLIC_LINK_TYPE;
break;
case 'l':
type = FTPFile.SYMBOLIC_LINK_TYPE;
break;
case 'b':
case 'c':
isDevice = true;
type = FTPFile.FILE_TYPE; // TODO change this if DEVICE_TYPE implemented
break;
case 'f':
case '-':
type = FTPFile.FILE_TYPE;
break;
default: // e.g. ? and w = whiteout
type = FTPFile.UNKNOWN_TYPE;
}
file.setType(type);
int g = 4;
for (int access = 0; access < 3; access++, g += 4) {
// Use != '-' to avoid having to check for suid and sticky bits
file.setPermission(access, FTPFile.READ_PERMISSION, (!group(g).equals("-")));
file.setPermission(access, FTPFile.WRITE_PERMISSION, (!group(g + 1).equals("-")));
String execPerm = group(g + 2);
if (!execPerm.equals("-") && !Character.isUpperCase(execPerm.charAt(0))) {
file.setPermission(access, FTPFile.EXECUTE_PERMISSION, true);
}
else {
file.setPermission(access, FTPFile.EXECUTE_PERMISSION, false);
}
}
if (!isDevice) {
try {
file.setHardLinkCount(Integer.parseInt(hardLinkCount));
}
catch (NumberFormatException e) {
// intentionally do nothing
}
}
file.setUser(usr);
file.setGroup(grp);
try {
file.setSize(Long.parseLong(filesize));
}
catch (NumberFormatException e) {
// intentionally do nothing
}
// oddball cases like symbolic links, file names
// with spaces in them.
if (type == FTPFile.SYMBOLIC_LINK_TYPE) {
int end = name.indexOf(" -> ");
// Give up if no link indicator is present
if (end == -1) {
file.setName(name);
}
else {
file.setName(name.substring(0, end));
file.setLink(name.substring(end + 4));
}
}
else {
file.setName(name);
}
return file;
}
return null;
}
/**
* Defines a default configuration to be used when this class is instantiated without a
* {@link FTPClientConfig FTPClientConfig} parameter being specified.
*
* @return the default configuration for this parser.
*/
@Override
protected FTPClientConfig getDefaultConfiguration() {
return new FTPClientConfig(FTPClientConfig.SYST_UNIX, DEFAULT_DATE_FORMAT, DEFAULT_RECENT_DATE_FORMAT, null,
null, null);
}
}