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|
// Copyright (C) 2015, The Duplicati Team
// http://www.duplicati.com, info@duplicati.com
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.Text;
using System.Text.RegularExpressions;
using Duplicati.Library.Common.IO;
using Duplicati.Library.Common;
using System.Globalization;
namespace Duplicati.Library.Utility
{
public static class Utility
{
/// <summary>
/// Size of buffers for copying stream
/// </summary>
public static long DEFAULT_BUFFER_SIZE => SystemContextSettings.Buffersize;
/// <summary>
/// A cache of the FileSystemCaseSensitive property, which is computed upon the first access.
/// </summary>
private static bool? CachedIsFSCaseSensitive;
/// <summary>
/// Gets the hash algorithm used for calculating a hash
/// </summary>
public static string HashAlgorithm => "SHA256";
/// <summary>
/// The EPOCH offset (unix style)
/// </summary>
public static readonly DateTime EPOCH = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
/// <summary>
/// The attribute value used to indicate error
/// </summary>
public const FileAttributes ATTRIBUTE_ERROR = (FileAttributes)(1 << 30);
/// <summary>
/// The callback delegate type used to collecting file information
/// </summary>
/// <param name="rootpath">The path that the file enumeration started at</param>
/// <param name="path">The current element</param>
/// <param name="attributes">The attributes of the element</param>
/// <returns>A value indicating if the folder should be recursed, ignored for other types</returns>
public delegate bool EnumerationFilterDelegate(string rootpath, string path, FileAttributes attributes);
/// <summary>
/// Copies the content of one stream into another
/// </summary>
/// <param name="source">The stream to read from</param>
/// <param name="target">The stream to write to</param>
public static long CopyStream(Stream source, Stream target)
{
return CopyStream(source, target, true);
}
/// <summary>
/// Copies the content of one stream into another
/// </summary>
/// <param name="source">The stream to read from</param>
/// <param name="target">The stream to write to</param>
/// <param name="tryRewindSource">True if an attempt should be made to rewind the source stream, false otherwise</param>
/// <param name="buf">Temporary buffer to use (optional)</param>
public static long CopyStream(Stream source, Stream target, bool tryRewindSource, byte[] buf = null)
{
if (tryRewindSource && source.CanSeek)
try { source.Position = 0; }
catch
{
// ignored
}
buf = buf ?? new byte[DEFAULT_BUFFER_SIZE];
int read;
long total = 0;
while ((read = source.Read(buf, 0, buf.Length)) != 0)
{
target.Write(buf, 0, read);
total += read;
}
return total;
}
/// <summary>
/// Copies the content of one stream into another
/// </summary>
/// <param name="source">The stream to read from</param>
/// <param name="target">The stream to write to</param>
/// <param name="cancelToken">Token to cancel the operation.</param>
public static async Task<long> CopyStreamAsync(Stream source, Stream target, CancellationToken cancelToken)
{
return await CopyStreamAsync(source, target, tryRewindSource: true, cancelToken: cancelToken).ConfigureAwait(false);
}
/// <summary>
/// Copies the content of one stream into another
/// </summary>
/// <param name="source">The stream to read from</param>
/// <param name="target">The stream to write to</param>
/// <param name="tryRewindSource">True if an attempt should be made to rewind the source stream, false otherwise</param>
/// <param name="cancelToken">Token to cancel the operation.</param>
/// <param name="buf">Temporary buffer to use (optional)</param>
public static async Task<long> CopyStreamAsync(Stream source, Stream target, bool tryRewindSource, CancellationToken cancelToken, byte[] buf = null)
{
if (tryRewindSource && source.CanSeek)
try { source.Position = 0; }
catch {}
buf = buf ?? new byte[DEFAULT_BUFFER_SIZE];
int read;
long total = 0;
while (true)
{
read = await source.ReadAsync(buf, 0, buf.Length, cancelToken).ConfigureAwait(false);
if (read == 0) break;
await target.WriteAsync(buf, 0, read, cancelToken).ConfigureAwait(false);
total += read;
}
return total;
}
/// <summary>
/// These are characters that must be escaped when using a globbing expression
/// </summary>
private static readonly string BADCHARS = @"\\|\+|\||\{|\[|\(|\)|\]|\}|\^|\$|\#|\.";
/// <summary>
/// Most people will probably want to use fileglobbing, but RegExp's are more flexible.
/// By converting from the weak globbing to the stronger regexp, we support both.
/// </summary>
/// <param name="globexp"></param>
/// <returns></returns>
public static string ConvertGlobbingToRegExp(string globexp)
{
//First escape all special characters
globexp = Regex.Replace(globexp, BADCHARS, @"\$&");
//Replace the globbing expressions with the corresponding regular expressions
globexp = globexp.Replace('?', '.').Replace("*", ".*");
return globexp;
}
/// <summary>
/// Convert literal path to the equivalent regular expression.
/// </summary>
public static string ConvertLiteralToRegExp(string literalPath)
{
// Escape all special characters
return Regex.Escape(literalPath);
}
/// <summary>
/// Returns a list of all files found in the given folder.
/// The search is recursive.
/// </summary>
/// <param name="basepath">The folder to look in</param>
/// <returns>A list of the full filenames</returns>
public static IEnumerable<string> EnumerateFiles(string basepath)
{
return EnumerateFileSystemEntries(basepath).Where(x => !x.EndsWith(Util.DirectorySeparatorString, StringComparison.Ordinal));
}
/// <summary>
/// Returns a list of folder names found in the given folder.
/// The search is recursive.
/// </summary>
/// <param name="basepath">The folder to look in</param>
/// <returns>A list of the full paths</returns>
public static IEnumerable<string> EnumerateFolders(string basepath)
{
return EnumerateFileSystemEntries(basepath).Where(x => x.EndsWith(Util.DirectorySeparatorString, StringComparison.Ordinal));
}
/// <summary>
/// Returns a list of all files and subfolders found in the given folder.
/// The search is recursive.
/// </summary>
/// <param name="basepath">The folder to look in.</param>
/// <returns>A list of the full filenames and foldernames. Foldernames ends with the directoryseparator char</returns>
public static IEnumerable<string> EnumerateFileSystemEntries(string basepath)
{
return EnumerateFileSystemEntries(basepath, (rootpath, path, attributes) => true, SystemIO.IO_OS.GetDirectories, Directory.GetFiles, null);
}
/// <summary>
/// A callback delegate used for applying alternate enumeration of filesystems
/// </summary>
/// <param name="path">The path to return data from</param>
/// <returns>A list of paths</returns>
public delegate string[] FileSystemInteraction(string path);
/// <summary>
/// A callback delegate used for extracting attributes from a file or folder
/// </summary>
/// <param name="path">The path to return data from</param>
/// <returns>Attributes for the file or folder</returns>
public delegate FileAttributes ExtractFileAttributes(string path);
/// <summary>
/// A callback delegate used for extracting attributes from a file or folder
/// </summary>
/// <param name="rootpath">The root folder where the path was found</param>
/// <param name="path">The path that produced the error</param>
/// <param name="ex">The exception for the error</param>
public delegate void ReportAccessError(string rootpath, string path, Exception ex);
/// <summary>
/// Returns a list of all files found in the given folder.
/// The search is recursive.
/// </summary>
/// <param name="rootpath">The folder to look in</param>
/// <param name="callback">The function to call with the filenames</param>
/// <param name="folderList">A function to call that lists all folders in the supplied folder</param>
/// <param name="fileList">A function to call that lists all files in the supplied folder</param>
/// <param name="attributeReader">A function to call that obtains the attributes for an element, set to null to avoid reading attributes</param>
/// <param name="errorCallback">An optional function to call with error messages.</param>
/// <returns>A list of the full filenames</returns>
public static IEnumerable<string> EnumerateFileSystemEntries(string rootpath, EnumerationFilterDelegate callback, FileSystemInteraction folderList, FileSystemInteraction fileList, ExtractFileAttributes attributeReader, ReportAccessError errorCallback = null)
{
var lst = new Stack<string>();
if (IsFolder(rootpath, attributeReader))
{
rootpath = Util.AppendDirSeparator(rootpath);
try
{
var attr = attributeReader?.Invoke(rootpath) ?? FileAttributes.Directory;
if (callback(rootpath, rootpath, attr))
lst.Push(rootpath);
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, rootpath, ex);
callback(rootpath, rootpath, FileAttributes.Directory | ATTRIBUTE_ERROR);
}
while (lst.Count > 0)
{
var f = lst.Pop();
yield return f;
try
{
foreach (var s in folderList(f))
{
var sf = Util.AppendDirSeparator(s);
try
{
var attr = attributeReader?.Invoke(sf) ?? FileAttributes.Directory;
if (callback(rootpath, sf, attr))
lst.Push(sf);
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, sf, ex);
callback(rootpath, sf, FileAttributes.Directory | ATTRIBUTE_ERROR);
}
}
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, f, ex);
callback(rootpath, f, FileAttributes.Directory | ATTRIBUTE_ERROR);
}
string[] files = null;
if (fileList != null)
{
try
{
files = fileList(f);
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, f, ex);
callback(rootpath, f, FileAttributes.Directory | ATTRIBUTE_ERROR);
}
}
if (files != null)
{
foreach (var s in files)
{
try
{
var attr = attributeReader?.Invoke(s) ?? FileAttributes.Normal;
if (!callback(rootpath, s, attr))
continue;
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, s, ex);
callback(rootpath, s, ATTRIBUTE_ERROR);
continue;
}
yield return s;
}
}
}
}
else
{
try
{
var attr = attributeReader?.Invoke(rootpath) ?? FileAttributes.Normal;
if (!callback(rootpath, rootpath, attr))
yield break;
}
catch (System.Threading.ThreadAbortException)
{
throw;
}
catch (Exception ex)
{
errorCallback?.Invoke(rootpath, rootpath, ex);
callback(rootpath, rootpath, ATTRIBUTE_ERROR);
yield break;
}
yield return rootpath;
}
}
/// <summary>
/// Test if specified path is a folder
/// </summary>
/// <param name="path">Path to test</param>
/// <param name="attributeReader">Function to use for testing path</param>
/// <returns>True if path is refers to a folder</returns>
public static bool IsFolder(string path, ExtractFileAttributes attributeReader)
{
if (attributeReader == null)
return true;
try
{
return attributeReader(path).HasFlag(FileAttributes.Directory);
}
catch
{
return false;
}
}
/// <summary>
/// Tests if path refers to a file, or folder, <b>below</b> the parent folder
/// </summary>
/// <param name="fileOrFolderPath">File or folder to test</param>
/// <param name="parentFolder">Candidate parent folder</param>
/// <returns>True if below parent folder, false otherwise
/// (note that this returns false if the two argument paths are identical!)</returns>
public static bool IsPathBelowFolder(string fileOrFolderPath, string parentFolder)
{
var sanitizedParentFolder = Util.AppendDirSeparator(parentFolder);
return fileOrFolderPath.StartsWith(sanitizedParentFolder, ClientFilenameStringComparison) &&
!fileOrFolderPath.Equals(sanitizedParentFolder, ClientFilenameStringComparison);
}
/// <summary>
/// Returns parent folder of path
/// </summary>
/// <param name="path">Full file or folder path</param>
/// <param name="forceTrailingDirectorySeparator">If true, return value always has trailing separator</param>
/// <returns>Parent folder of path (containing folder for file paths, parent folder for folder paths)</returns>
public static string GetParent(string path, bool forceTrailingDirectorySeparator)
{
var len = path.Length - 1;
if (len > 1 && path[len] == Path.DirectorySeparatorChar)
{
len--;
}
var last = path.LastIndexOf(Path.DirectorySeparatorChar, len);
if (last == -1 || last == 0 && len == 0)
return null;
if (last == 0 && !Platform.IsClientWindows)
return Util.DirectorySeparatorString;
var parent = path.Substring(0, last);
if (forceTrailingDirectorySeparator ||
Platform.IsClientWindows && parent.Length == 2 && parent[1] == ':' && char.IsLetter(parent[0]))
{
parent += Path.DirectorySeparatorChar;
}
return parent;
}
/// <summary>
/// Given a collection of unique folders, returns only parent-most folders
/// </summary>
/// <param name="folders">Collection of unique folders</param>
/// <returns>Parent-most folders of input collection</returns>
public static IEnumerable<string> SimplifyFolderList(ICollection<string> folders)
{
if (!folders.Any())
return folders;
var result = new LinkedList<string>();
result.AddFirst(folders.First());
foreach (var folder1 in folders)
{
bool addFolder = true;
LinkedListNode<string> next;
for (var node = result.First; node != null; node = next)
{
next = node.Next;
var folder2 = node.Value;
if (IsPathBelowFolder(folder1, folder2))
{
// higher-level folder already present
addFolder = false;
break;
}
if (IsPathBelowFolder(folder2, folder1))
{
// retain folder1
result.Remove(node);
}
}
if (addFolder)
{
result.AddFirst(folder1);
}
}
return result.Distinct();
}
/// <summary>
/// Given a collection of file paths, return those NOT contained within specified collection of folders
/// </summary>
/// <param name="files">Collection of files to filter</param>
/// <param name="folders">Collection of folders to use as filter</param>
/// <returns>Files not in any of specified <c>folders</c></returns>
public static IEnumerable<string> GetFilesNotInFolders(IEnumerable<string> files, IEnumerable<string> folders)
{
return files.Where(x => folders.All(folder => !IsPathBelowFolder(x, folder)));
}
/// <summary>
/// Calculates the size of files in a given folder
/// </summary>
/// <param name="folder">The folder to examine</param>
/// <returns>The combined size of all files that match the filter</returns>
public static long GetDirectorySize(string folder)
{
return EnumerateFolders(folder).Sum((path) => new FileInfo(path).Length);
}
/// <summary>
/// Some streams can return a number that is less than the requested number of bytes.
/// This is usually due to fragmentation, and is solved by issuing a new read.
/// This function wraps that functionality.
/// </summary>
/// <param name="stream">The stream to read</param>
/// <param name="buf">The buffer to read into</param>
/// <param name="count">The amount of bytes to read</param>
/// <returns>The actual number of bytes read</returns>
public static int ForceStreamRead(Stream stream, byte[] buf, int count)
{
int a;
int index = 0;
do
{
a = stream.Read(buf, index, count);
index += a;
count -= a;
} while (a != 0 && count > 0);
return index;
}
/// <summary>
/// Some streams can return a number that is less than the requested number of bytes.
/// This is usually due to fragmentation, and is solved by issuing a new read.
/// This function wraps that functionality.
/// </summary>
/// <param name="stream">The stream to read.</param>
/// <param name="buf">The buffer to read into.</param>
/// <param name="count">The amount of bytes to read.</param>
/// <returns>The number of bytes read</returns>
public static async Task<int> ForceStreamReadAsync(this System.IO.Stream stream, byte[] buf, int count)
{
int a;
int index = 0;
do
{
a = await stream.ReadAsync(buf, index, count).ConfigureAwait(false);
index += a;
count -= a;
} while (a != 0 && count > 0);
return index;
}
/// <summary>
/// Compares two streams to see if they are binary equals
/// </summary>
/// <param name="stream1">One stream</param>
/// <param name="stream2">Another stream</param>
/// <param name="checkLength">True if the length of the two streams should be compared</param>
/// <returns>True if they are equal, false otherwise</returns>
public static bool CompareStreams(Stream stream1, Stream stream2, bool checkLength)
{
if (checkLength)
{
try
{
if (stream1.Length != stream2.Length)
return false;
}
catch
{
//We must read along, trying to determine if they are equals
}
}
int longSize = BitConverter.GetBytes((long)0).Length;
byte[] buf1 = new byte[longSize * 512];
byte[] buf2 = new byte[buf1.Length];
int a1, a2;
while ((a1 = ForceStreamRead(stream1, buf1, buf1.Length)) == (a2 = ForceStreamRead(stream2, buf2, buf2.Length)))
{
int ix = 0;
for (int i = 0; i < a1 / longSize; i++)
if (BitConverter.ToUInt64(buf1, ix) != BitConverter.ToUInt64(buf2, ix))
return false;
else
ix += longSize;
for (int i = 0; i < a1 % longSize; i++)
if (buf1[ix] != buf2[ix])
return false;
else
ix++;
if (a1 == 0)
break;
}
return a1 == a2;
}
/// <summary>
/// Calculates the hash of a given stream, and returns the results as an base64 encoded string
/// </summary>
/// <param name="stream">The stream to calculate the hash for</param>
/// <returns>The base64 encoded hash</returns>
public static string CalculateHash(Stream stream)
{
return Convert.ToBase64String(HashAlgorithmHelper.Create(HashAlgorithm).ComputeHash(stream));
}
/// <summary>
/// Reads a file, attempts to detect encoding
/// </summary>
/// <param name="filename">The path to the file to read</param>
/// <returns>The file contents</returns>
public static string ReadFileWithDefaultEncoding(string filename)
{
// Since StreamReader defaults to UTF8 and most text files will NOT be UTF8 without BOM,
// we need to detect the encoding (at least that it's not UTF8).
// So we read the first 4096 bytes and try to decode them as UTF8.
var buffer = new byte[4096];
using (var file = new FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.Read))
{
Utility.ForceStreamRead(file, buffer, 4096);
}
var enc = Encoding.UTF8;
try
{
// this will throw an error if not really UTF8
// ReSharper disable once ReturnValueOfPureMethodIsNotUsed
new UTF8Encoding(false, true).GetString(buffer);
}
catch (Exception)
{
enc = Encoding.Default;
}
// This will load the text using the BOM, or the detected encoding if no BOM.
using (var reader = new StreamReader(filename, enc, true))
{
// Remove all \r from the file and split on \n, then pass directly to ExtractOptions
return reader.ReadToEnd();
}
}
/// <summary>
/// Formats a size into a human readable format, eg. 2048 becomes "2 KB" or -2283 becomes "-2.23 KB%quot.
/// </summary>
/// <param name="size">The size to format</param>
/// <returns>A human readable string representing the size</returns>
public static string FormatSizeString(double size)
{
double sizeAbs = Math.Abs(size); // Allow formatting of negative sizes
if (sizeAbs >= 1024 * 1024 * 1024 * 1024L)
return Strings.Utility.FormatStringTB(size / (1024 * 1024 * 1024 * 1024L));
else if (sizeAbs >= 1024 * 1024 * 1024)
return Strings.Utility.FormatStringGB(size / (1024 * 1024 * 1024));
else if (sizeAbs >= 1024 * 1024)
return Strings.Utility.FormatStringMB(size / (1024 * 1024));
else if (sizeAbs >= 1024)
return Strings.Utility.FormatStringKB(size / 1024);
else
return Strings.Utility.FormatStringB((long) size); // safe to cast because lower than 1024 and thus well within range of long
}
public static System.Threading.ThreadPriority ParsePriority(string value)
{
if (string.IsNullOrEmpty(value) || value.Trim().Length == 0)
return System.Threading.ThreadPriority.Normal;
switch (value.ToLower(CultureInfo.InvariantCulture).Trim())
{
case "+2":
case "high":
case "highest":
return System.Threading.ThreadPriority.Highest;
case "+1":
case "abovenormal":
case "above normal":
return System.Threading.ThreadPriority.AboveNormal;
case "-1":
case "belownormal":
case "below normal":
return System.Threading.ThreadPriority.BelowNormal;
case "-2":
case "low":
case "lowest":
case "idle":
return System.Threading.ThreadPriority.Lowest;
default:
return System.Threading.ThreadPriority.Normal;
}
}
/// <summary>
/// Parses a string into a boolean value.
/// </summary>
/// <param name="value">The value to parse.</param>
/// <param name="defaultFunc">A delegate that returns the default value if <paramref name="value"/> is not a valid boolean value.</param>
/// <returns>The parsed value, or the value returned by <paramref name="defaultFunc"/>.</returns>
public static bool ParseBool(string value, Func<bool> defaultFunc)
{
if (String.IsNullOrWhiteSpace(value))
{
return defaultFunc();
}
switch (value.Trim().ToLower(CultureInfo.InvariantCulture))
{
case "1":
case "on":
case "true":
case "yes":
return true;
case "0":
case "off":
case "false":
case "no":
return false;
default:
return defaultFunc();
}
}
/// <summary>
/// Parses a string into a boolean value.
/// </summary>
/// <param name="value">The value to parse.</param>
/// <param name="default">The default value, in case <paramref name="value"/> is not a valid boolean value.</param>
/// <returns>The parsed value, or the default value.</returns>
public static bool ParseBool(string value, bool @default)
{
return ParseBool(value, () => @default);
}
/// <summary>
/// Parses an option from the option set, using the convention that if the option is set, it is true unless it parses to false, and false otherwise
/// </summary>
/// <param name="options">The set of options to look for the setting in</param>
/// <param name="value">The value to look for in the settings</param>
/// <returns></returns>
public static bool ParseBoolOption(IDictionary<string, string> options, string value)
{
string opt;
if (options.TryGetValue(value, out opt))
return ParseBool(opt, true);
else
return false;
}
/// <summary>
/// Parses an enum found in the options dictionary
/// </summary>
/// <returns>The parsed or default enum value.</returns>
/// <param name="options">The set of options to look for the setting in</param>
/// <param name="value">The value to look for in the settings</param>
/// <param name="default">The default value to return if there are no matches.</param>
/// <typeparam name="T">The enum type parameter.</typeparam>
public static T ParseEnumOption<T>(IDictionary<string, string> options, string value, T @default)
{
return options.TryGetValue(value, out var opt) ? ParseEnum(opt, @default) : @default;
}
/// <summary>
/// Attempts to parse an enum with case-insensitive lookup, returning the default value if there was no match
/// </summary>
/// <returns>The parsed or default enum value.</returns>
/// <param name="value">The string to parse.</param>
/// <param name="default">The default value to return if there are no matches.</param>
/// <typeparam name="T">The enum type parameter.</typeparam>
public static T ParseEnum<T>(string value, T @default)
{
foreach (var s in Enum.GetNames(typeof(T)))
if (s.Equals(value, StringComparison.OrdinalIgnoreCase))
return (T)Enum.Parse(typeof(T), s);
return @default;
}
/// <summary>
/// Converts a sequence of bytes to a hex string
/// </summary>
/// <returns>The array as hex string.</returns>
/// <param name="data">The data to convert</param>
public static string ByteArrayAsHexString(byte[] data)
{
return BitConverter.ToString(data).Replace("-", string.Empty);
}
/// <summary>
/// Converts a hex string to a byte array
/// </summary>
/// <returns>The string as byte array.</returns>
/// <param name="hex">The hex string</param>
/// <param name="data">The parsed data</param>
public static void HexStringAsByteArray(string hex, byte[] data)
{
for (var i = 0; i < hex.Length; i += 2)
data[i / 2] = Convert.ToByte(hex.Substring(i, 2), 16);
}
public static bool Which(string appname)
{
if (!Platform.IsClientPosix)
return false;
try
{
var psi = new System.Diagnostics.ProcessStartInfo("which", appname)
{
RedirectStandardOutput = true,
RedirectStandardError = false,
RedirectStandardInput = false,
UseShellExecute = false
};
var pi = System.Diagnostics.Process.Start(psi);
pi.WaitForExit(5000);
if (pi.HasExited)
return pi.ExitCode == 0;
else
return false;
}
catch
{
}
return false;
}
/// <value>
/// Returns a value indicating if the filesystem, is case sensitive
/// </value>
public static bool IsFSCaseSensitive
{
get
{
if (!CachedIsFSCaseSensitive.HasValue)
{
var str = Environment.GetEnvironmentVariable("FILESYSTEM_CASE_SENSITIVE");
// TODO: This should probably be determined by filesystem rather than OS,
// OSX can actually have the disks formatted as Case Sensitive, but insensitive is default
CachedIsFSCaseSensitive = ParseBool(str, () => Platform.IsClientPosix && !Platform.IsClientOSX);
}
return CachedIsFSCaseSensitive.Value;
}
}
/// <summary>
/// Returns a value indicating if the app is running under Mono
/// </summary>
public static bool IsMono => Type.GetType("Mono.Runtime") != null;
/// <summary>
/// Gets the current Mono runtime version, will return 0.0 if not running Mono
/// </summary>
public static Version MonoVersion
{
get
{
try
{
var v = MonoDisplayVersion;
if (v != null)
{
var regex = new Regex(@"\d+\.\d+(\.\d+)?(\.\d+)?");
var match = regex.Match(v);
if (match.Success)
return new Version(match.Value);
}
}
catch
{
// ignored
}
return new Version();
}
}
/// <summary>
/// Gets the Mono display version, or null if not running Mono
/// </summary>
public static string MonoDisplayVersion
{
get
{
try
{
var t = Type.GetType("Mono.Runtime");
if (t != null)
{
var mi = t.GetMethod("GetDisplayName", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic);
if (mi != null)
return (string)mi.Invoke(null, null);
}
}
catch
{
// ignored
}
return null;
}
}
/// <summary>
/// Gets a string comparer that matches the client filesystems case sensitivity
/// </summary>
public static StringComparer ClientFilenameStringComparer => IsFSCaseSensitive ? StringComparer.Ordinal : StringComparer.OrdinalIgnoreCase;
/// <summary>
/// Gets the string comparision that matches the client filesystems case sensitivity
/// </summary>
public static StringComparison ClientFilenameStringComparison => IsFSCaseSensitive ? StringComparison.Ordinal : StringComparison.OrdinalIgnoreCase;
/// <summary>
/// The path to the users home directory
/// </summary>
public static readonly string HOME_PATH = Environment.GetFolderPath(Platform.IsClientPosix ? Environment.SpecialFolder.Personal : Environment.SpecialFolder.UserProfile);
/// <summary>
/// Regexp for matching environment variables on Windows (%VAR%)
/// </summary>
private static readonly Regex ENVIRONMENT_VARIABLE_MATCHER_WINDOWS = new Regex(@"\%(?<name>\w+)\%");
/// <summary>
/// Expands environment variables in a RegExp safe format
/// </summary>
/// <returns>The expanded string.</returns>
/// <param name="str">The string to expand.</param>
/// <param name="lookup">A lookup method that converts an environment key to an expanded string</param>
public static string ExpandEnvironmentVariablesRegexp(string str, Func<string, string> lookup = null)
{
if (lookup == null)
lookup = Environment.GetEnvironmentVariable;
return
// TODO: Should we switch to using the native format ($VAR or ${VAR}), instead of following the Windows scheme?
// IsClientLinux ? new Regex(@"\$(?<name>\w+)|(\{(?<name>[^\}]+)\})") : ENVIRONMENT_VARIABLE_MATCHER_WINDOWS
ENVIRONMENT_VARIABLE_MATCHER_WINDOWS.Replace(str, m => Regex.Escape(lookup(m.Groups["name"].Value)));
}
/// <summary>
/// Normalizes a DateTime instance by converting to UTC and flooring to seconds.
/// </summary>
/// <returns>The normalized date time</returns>
/// <param name="input">The input time</param>
public static DateTime NormalizeDateTime(DateTime input)
{
var ticks = input.ToUniversalTime().Ticks;
ticks -= ticks % TimeSpan.TicksPerSecond;
return new DateTime(ticks, DateTimeKind.Utc);
}
/// <summary>
/// Given a DateTime instance, return the number of elapsed seconds since the Unix epoch
/// </summary>
/// <returns>The number of elapsed seconds since the Unix epoch</returns>
/// <param name="input">The input time</param>
public static long NormalizeDateTimeToEpochSeconds(DateTime input)
{
// Note that we cannot return (new DateTimeOffset(input)).ToUnixTimeSeconds() here.
// The DateTimeOffset constructor will convert the provided DateTime to the UTC
// equivalent. However, if DateTime.MinValue is provided (for example, when creating
// a new backup), this can result in values that fall outside the DateTimeOffset.MinValue
// and DateTimeOffset.MaxValue bounds.
return (long) Math.Floor((NormalizeDateTime(input) - EPOCH).TotalSeconds);
}
/// <summary>
/// The format string for a DateTime
/// </summary>
//Note: Actually the K should be Z which is more correct as it is forced to be Z, but Z as a format specifier is fairly undocumented
public static string SERIALIZED_DATE_TIME_FORMAT = "yyyyMMdd'T'HHmmssK";
/// <summary>
/// Returns a string representation of a <see cref="System.DateTime"/> in UTC format
/// </summary>
/// <param name="dt">The <see cref="System.DateTime"/> instance</param>
/// <returns>A string representing the time</returns>
public static string SerializeDateTime(DateTime dt)
{
return dt.ToUniversalTime().ToString(SERIALIZED_DATE_TIME_FORMAT, System.Globalization.CultureInfo.InvariantCulture);
}
/// <summary>
/// Parses a serialized <see cref="System.DateTime"/> instance
/// </summary>
/// <param name="str">The string to parse</param>
/// <returns>The parsed <see cref="System.DateTime"/> instance</returns>
public static bool TryDeserializeDateTime(string str, out DateTime dt)
{
return DateTime.TryParseExact(str, SERIALIZED_DATE_TIME_FORMAT, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.AssumeUniversal, out dt);
}
/// <summary>
/// Parses a serialized <see cref="System.DateTime"/> instance
/// </summary>
/// <param name="str">The string to parse</param>
/// <returns>The parsed <see cref="System.DateTime"/> instance</returns>
public static DateTime DeserializeDateTime(string str)
{
if (!TryDeserializeDateTime(str, out var dt))
throw new Exception(Strings.Utility.InvalidDateError(str));
return dt;
}
/// <summary>
/// Gets the unique items from a collection.
/// </summary>
/// <typeparam name="T">The type of the elements in <paramref name="collection"/>.</typeparam>
/// <param name="collection">The collection to remove duplicate items from.</param>
/// <param name="duplicateItems">The duplicate items in <paramref name="collection"/>.</param>
/// <returns>The unique items from <paramref name="collection"/>.</returns>
public static ISet<T> GetUniqueItems<T>(IEnumerable<T> collection, out ISet<T> duplicateItems)
{
return GetUniqueItems(collection, EqualityComparer<T>.Default, out duplicateItems);
}
/// <summary>
/// Gets the unique items from a collection.
/// </summary>
/// <typeparam name="T">The type of the elements in <paramref name="collection"/>.</typeparam>
/// <param name="collection">The collection to remove duplicate items from.</param>
/// <param name="comparer">The <see cref="System.Collections.Generic.IEqualityComparer{T}"/> implementation to use when comparing values in the collection.</param>
/// <param name="duplicateItems">The duplicate items in <paramref name="collection"/>.</param>
/// <returns>The unique items from <paramref name="collection"/>.</returns>
public static ISet<T> GetUniqueItems<T>(IEnumerable<T> collection, IEqualityComparer<T> comparer, out ISet<T> duplicateItems)
{
var uniqueItems = new HashSet<T>(comparer);
duplicateItems = new HashSet<T>(comparer);
foreach (var item in collection)
{
if (!uniqueItems.Add(item))
duplicateItems.Add(item);
}
return uniqueItems;
}
// <summary>
// Returns the entry assembly or reasonable approximation if no entry assembly is available.
// This is the case in NUnit tests. The following approach does not work w/ Mono due to unimplemented members:
// http://social.msdn.microsoft.com/Forums/nb-NO/clr/thread/db44fe1a-3bb4-41d4-a0e0-f3021f30e56f
// so this layer of indirection is necessary
// </summary>
// <returns>entry assembly or reasonable approximation</returns>
public static System.Reflection.Assembly getEntryAssembly()
{
return System.Reflection.Assembly.GetEntryAssembly() ?? System.Reflection.Assembly.GetExecutingAssembly();
}
/// <summary>
/// Converts a Base64 encoded string to "base64 for url"
/// See https://en.wikipedia.org/wiki/Base64#URL_applications
/// </summary>
/// <param name="data">The base64 encoded string</param>
/// <returns>The base64 for url encoded string</returns>
public static string Base64PlainToBase64Url(string data)
{
return data.Replace('+', '-').Replace('/', '_');
}
/// <summary>
/// Converts a "base64 for url" encoded string to a Base64 encoded string.
/// See https://en.wikipedia.org/wiki/Base64#URL_applications
/// </summary>
/// <param name="data">The base64 for url encoded string</param>
/// <returns>The base64 encoded string</returns>
public static string Base64UrlToBase64Plain(string data)
{
return data.Replace('-', '+').Replace('_', '/');
}
/// <summary>
/// Encodes a byte array into a "base64 for url" encoded string.
/// See https://en.wikipedia.org/wiki/Base64#URL_applications
/// </summary>
/// <param name="data">The data to encode</param>
/// <returns>The base64 for url encoded string</returns>
public static string Base64UrlEncode(byte[] data)
{
return Base64PlainToBase64Url(Convert.ToBase64String(data));
}
/// <summary>
/// Converts a DateTime instance to a Unix timestamp
/// </summary>
/// <returns>The Unix timestamp.</returns>
/// <param name="input">The DateTime instance to convert.</param>
public static long ToUnixTimestamp(DateTime input)
{
var ticks = input.ToUniversalTime().Ticks;
ticks -= ticks % TimeSpan.TicksPerSecond;
input = new DateTime(ticks, DateTimeKind.Utc);
return (long)Math.Floor((input - EPOCH).TotalSeconds);
}
/// <summary>
/// Returns a value indicating if the given type should be treated as a primitive
/// </summary>
/// <returns><c>true</c>, if type is primitive for serialization, <c>false</c> otherwise.</returns>
/// <param name="t">The type to check.</param>
private static bool IsPrimitiveTypeForSerialization(Type t)
{
return t.IsPrimitive || t.IsEnum || t == typeof(string) || t == typeof(DateTime) || t == typeof(TimeSpan);
}
/// <summary>
/// Writes a primitive to the output, or returns false if the input is not primitive
/// </summary>
/// <returns><c>true</c>, the item was printed, <c>false</c> otherwise.</returns>
/// <param name="item">The item to write.</param>
/// <param name="writer">The target writer.</param>
private static bool PrintSerializeIfPrimitive(object item, TextWriter writer)
{
if (item == null)
{
writer.Write("null");
return true;
}
if (IsPrimitiveTypeForSerialization(item.GetType()))
{
if (item is DateTime time)
{
writer.Write(time.ToLocalTime());
writer.Write(" (");
writer.Write(ToUnixTimestamp(time));
writer.Write(")");
}
else
writer.Write(item);
return true;
}
return false;
}
/// <summary>
/// Prints the object to a stream, which can be used for display or logging
/// </summary>
/// <returns>The serialized object</returns>
/// <param name="item">The object to serialize</param>
/// <param name="writer">The writer to write the results to</param>
/// <param name="filter">A filter applied to properties to decide if they are omitted or not</param>
/// <param name="recurseobjects">A value indicating if non-primitive values are recursed</param>
/// <param name="indentation">The string indentation</param>
/// <param name="visited">A lookup table with visited objects, used to avoid infinite recursion</param>
/// <param name="collectionlimit">The maximum number of items to report from an IEnumerable instance</param>
public static void PrintSerializeObject(object item, TextWriter writer, Func<System.Reflection.PropertyInfo, object, bool> filter = null, bool recurseobjects = false, int indentation = 0, int collectionlimit = 0, Dictionary<object, object> visited = null)
{
visited = visited ?? new Dictionary<object, object>();
var indentstring = new string(' ', indentation);
var first = true;
if (item == null || IsPrimitiveTypeForSerialization(item.GetType()))
{
writer.Write(indentstring);
if (PrintSerializeIfPrimitive(item, writer))
return;
}
foreach (var p in item.GetType().GetProperties())
{
if (filter != null && !filter(p, item))
continue;
if (IsPrimitiveTypeForSerialization(p.PropertyType))
{
if (first)
first = false;
else
writer.WriteLine();
writer.Write("{0}{1}: ", indentstring, p.Name);
PrintSerializeIfPrimitive(p.GetValue(item, null), writer);
}
else if (typeof(Task).IsAssignableFrom(p.PropertyType) || p.Name == "TaskReader")
{
// Ignore Task items
continue;
}
else if (typeof(System.Collections.IEnumerable).IsAssignableFrom(p.PropertyType))
{
var enumerable = (System.Collections.IEnumerable)p.GetValue(item, null);
var any = false;
if (enumerable != null)
{
var enumerator = enumerable.GetEnumerator();
if (enumerator != null)
{
var remain = collectionlimit;
if (first)
first = false;
else
writer.WriteLine();
writer.Write("{0}{1}: [", indentstring, p.Name);
if (enumerator.MoveNext())
{
any = true;
writer.WriteLine();
PrintSerializeObject(enumerator.Current, writer, filter, recurseobjects, indentation + 4, collectionlimit, visited);
remain--;
while (enumerator.MoveNext())
{
writer.WriteLine(",");
if (remain == 0)
{
writer.Write("...");
break;
}
PrintSerializeObject(enumerator.Current, writer, filter, recurseobjects, indentation + 4, collectionlimit, visited);
remain--;
}
}
if (any)
{
writer.WriteLine();
writer.Write(indentstring);
}
writer.Write("]");
}
}
}
else if (recurseobjects)
{
var value = p.GetValue(item, null);
if (value == null)
{
if (first)
first = false;
else
writer.WriteLine();
writer.Write("{0}{1}: null", indentstring, p.Name);
}
else if (!visited.ContainsKey(value))
{
if (first)
first = false;
else
writer.WriteLine();
writer.WriteLine("{0}{1}:", indentstring, p.Name);
visited[value] = null;
PrintSerializeObject(value, writer, filter, recurseobjects, indentation + 4, collectionlimit, visited);
}
}
}
writer.Flush();
}
/// <summary>
/// Returns a string representing the object, which can be used for display or logging
/// </summary>
/// <returns>The serialized object</returns>
/// <param name="item">The object to serialize</param>
/// <param name="filter">A filter applied to properties to decide if they are omitted or not</param>
/// <param name="recurseobjects">A value indicating if non-primitive values are recursed</param>
/// <param name="indentation">The string indentation</param>
/// <param name="collectionlimit">The maximum number of items to report from an IEnumerable instance, set to zero or less for reporting all</param>
public static StringBuilder PrintSerializeObject(object item, StringBuilder sb = null, Func<System.Reflection.PropertyInfo, object, bool> filter = null, bool recurseobjects = false, int indentation = 0, int collectionlimit = 10)
{
sb = sb ?? new StringBuilder();
using (var sw = new StringWriter(sb))
PrintSerializeObject(item, sw, filter, recurseobjects, indentation, collectionlimit);
return sb;
}
/// <summary>
/// Repeatedly hash a value with a salt.
/// This effectively masks the original value,
/// and destroys lookup methods, like rainbow tables
/// </summary>
/// <param name="data">The data to hash</param>
/// <param name="salt">The salt to apply</param>
/// <param name="repeats">The number of times to repeat the hashing</param>
/// <returns>The salted hash</returns>
public static byte[] RepeatedHashWithSalt(string data, string salt, int repeats = 1200)
{
return RepeatedHashWithSalt(
Encoding.UTF8.GetBytes(data ?? ""),
Encoding.UTF8.GetBytes(salt ?? ""),
repeats);
}
/// <summary>
/// Repeatedly hash a value with a salt.
/// This effectively masks the original value,
/// and destroys lookup methods, like rainbow tables
/// </summary>
/// <param name="data">The data to hash</param>
/// <param name="salt">The salt to apply</param>
/// <returns>The salted hash</returns>
public static byte[] RepeatedHashWithSalt(byte[] data, byte[] salt, int repeats = 1200)
{
// We avoid storing the passphrase directly,
// instead we salt and rehash repeatedly
using (var h = System.Security.Cryptography.SHA256.Create())
{
h.Initialize();
h.TransformBlock(salt, 0, salt.Length, salt, 0);
h.TransformFinalBlock(data, 0, data.Length);
var buf = h.Hash;
for (var i = 0; i < repeats; i++)
{
h.Initialize();
h.TransformBlock(salt, 0, salt.Length, salt, 0);
h.TransformFinalBlock(buf, 0, buf.Length);
buf = h.Hash;
}
return buf;
}
}
/// <summary>
/// Gets the drive letter from the given volume guid.
/// This method cannot be inlined since the System.Management types are not implemented in Mono
/// </summary>
/// <param name="volumeGuid">Volume guid</param>
/// <returns>Drive letter, as a single character, or null if the volume wasn't found</returns>
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
public static string GetDriveLetterFromVolumeGuid(Guid volumeGuid)
{
// Based on this answer:
// https://stackoverflow.com/questions/10186277/how-to-get-drive-information-by-volume-id
using (System.Management.ManagementObjectSearcher searcher = new System.Management.ManagementObjectSearcher("Select * from Win32_Volume"))
{
string targetId = string.Format(@"\\?\Volume{{{0}}}\", volumeGuid);
foreach (System.Management.ManagementObject obj in searcher.Get())
{
if (string.Equals(obj["DeviceID"].ToString(), targetId, StringComparison.OrdinalIgnoreCase))
{
object driveLetter = obj["DriveLetter"];
if (driveLetter != null)
{
return obj["DriveLetter"].ToString();
}
else
{
// The volume was found, but doesn't have a drive letter associated with it.
break;
}
}
}
return null;
}
}
/// <summary>
/// Gets all volume guids and their associated drive letters.
/// This method cannot be inlined since the System.Management types are not implemented in Mono
/// </summary>
/// <returns>Pairs of drive letter to volume guids</returns>
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
public static IEnumerable<KeyValuePair<string, string>> GetVolumeGuidsAndDriveLetters()
{
using (var searcher = new System.Management.ManagementObjectSearcher("Select * from Win32_Volume"))
{
foreach (var obj in searcher.Get())
{
var deviceIdObj = obj["DeviceID"];
var driveLetterObj = obj["DriveLetter"];
if (deviceIdObj != null && driveLetterObj != null)
{
var deviceId = deviceIdObj.ToString();
var driveLetter = driveLetterObj.ToString();
if (!string.IsNullOrEmpty(deviceId) && !string.IsNullOrEmpty(driveLetter))
{
yield return new KeyValuePair<string, string>(driveLetter + @"\", deviceId);
}
}
}
}
}
/// <summary>
/// The regular expression matching all know non-quoted commandline characters
/// </summary>
private static readonly Regex COMMANDLINE_SAFE = new Regex(@"[A-Za-z0-9\-_/:\.]*");
/// <summary>
/// Special characters that needs to be escaped on Linux
/// </summary>
private static readonly Regex COMMANDLINE_ESCAPED_LINUX = new Regex(@"[""$`\\!]");
/// <summary>
/// Wraps a single argument in quotes suitable for the passing on the commandline
/// </summary>
/// <returns>The wrapped commandline element.</returns>
/// <param name="arg">The argument to wrap.</param>
/// <param name="allowEnvExpansion">A flag indicating if environment variables are allowed to be expanded</param>
public static string WrapCommandLineElement(string arg, bool allowEnvExpansion)
{
if (string.IsNullOrWhiteSpace(arg))
return arg;
if (!Platform.IsClientWindows)
{
// We could consider using single quotes that prevents all expansions
//if (!allowEnvExpansion)
// return "'" + arg.Replace("'", "\\'") + "'";
// Linux is using backslash to escape, except for !
arg = COMMANDLINE_ESCAPED_LINUX.Replace(arg, (match) =>
{
if (match.Value == "!")
return @"""'!'""";
if (match.Value == "$" && allowEnvExpansion)
return match.Value;
return @"\" + match.Value;
});
}
else
{
// Windows needs only needs " replaced with "",
// but is prone to %var% expansion when used in
// immediate mode (i.e. from command prompt)
// Fortunately it does not expand when processes
// are started from within .Net
// TODO: I have not found a way to avoid escaping %varname%,
// and sadly it expands only if the variable exists
// making it even rarer and harder to diagnose when
// it happens
arg = arg.Replace(@"""", @"""""");
// Also fix the case where the argument ends with a slash
if (arg[arg.Length - 1] == '\\')
arg += @"\";
}
// Check that all characters are in the safe set
if (COMMANDLINE_SAFE.Match(arg).Length != arg.Length)
return @"""" + arg + @"""";
else
return arg;
}
/// <summary>
/// Wrap a set of commandline arguments suitable for the commandline
/// </summary>
/// <returns>A commandline string.</returns>
/// <param name="args">The arguments to create into a commandline.</param>
/// <param name="allowEnvExpansion">A flag indicating if environment variables are allowed to be expanded</param>
public static string WrapAsCommandLine(IEnumerable<string> args, bool allowEnvExpansion = false)
{
return string.Join(" ", args.Select(x => WrapCommandLineElement(x, allowEnvExpansion)));
}
/// <summary>
/// Utility method that emulates C#'s built in await keyword without requiring the calling method to be async.
/// This method should be preferred over using Task.Result, as it doesn't wrap singular exceptions in AggregateExceptions.
/// (It uses Task.GetAwaiter().GetResult(), which is the same thing that await uses under the covers.)
/// https://stackoverflow.com/questions/17284517/is-task-result-the-same-as-getawaiter-getresult
/// </summary>
/// <param name="task">Task to await</param>
public static void Await(this Task task)
{
task.GetAwaiter().GetResult();
}
/// <summary>
/// Utility method that emulates C#'s built in await keyword without requiring the calling method to be async.
/// This method should be preferred over using Task.Result, as it doesn't wrap singular exceptions in AggregateExceptions.
/// (It uses Task.GetAwaiter().GetResult(), which is the same thing that await uses under the covers.)
/// https://stackoverflow.com/questions/17284517/is-task-result-the-same-as-getawaiter-getresult
/// </summary>
/// <typeparam name="T">Result type</typeparam>
/// <param name="task">Task to await</param>
/// <returns>Task result</returns>
public static T Await<T>(this Task<T> task)
{
return task.GetAwaiter().GetResult();
}
/// <summary>
/// Utility that computes the delay before the next retry of an operation, optionally using exponential backoff.
/// Note: when using exponential backoff, the exponent is clamped at 10.
/// </summary>
/// <param name="retryDelay">Value of one delay unit</param>
/// <param name="retryAttempt">The attempt number (e.g. 1 for the first retry, 2 for the second retry, etc.)</param>
/// <param name="useExponentialBackoff">Whether to use exponential backoff</param>
/// <returns>The computed delay</returns>
public static TimeSpan GetRetryDelay(TimeSpan retryDelay, int retryAttempt, bool useExponentialBackoff)
{
if (retryAttempt < 1)
{
throw new ArgumentException("The attempt number must not be less than 1.", nameof(retryAttempt));
}
TimeSpan delay;
if (useExponentialBackoff)
{
var delayTicks = retryDelay.Ticks << Math.Min(retryAttempt - 1, 10);
delay = TimeSpan.FromTicks(delayTicks);
}
else
{
delay = retryDelay;
}
return delay;
}
}
}
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