Files
sharpcompress/src/SharpCompress/Utility.cs
Adam Hathcock 48dbdbfed5 fmt
2026-01-06 12:49:26 +00:00

430 lines
12 KiB
C#

using System;
using System.Buffers;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.IO;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace SharpCompress;
internal static class Utility
{
//80kb is a good industry standard temporary buffer size
private const int TEMP_BUFFER_SIZE = 81920;
private static readonly HashSet<char> invalidChars = new(Path.GetInvalidFileNameChars());
public static ReadOnlyCollection<T> ToReadOnly<T>(this IList<T> items) => new(items);
/// <summary>
/// Performs an unsigned bitwise right shift with the specified number
/// </summary>
/// <param name="number">Number to operate on</param>
/// <param name="bits">Amount of bits to shift</param>
/// <returns>The resulting number from the shift operation</returns>
public static int URShift(int number, int bits) => (int)((uint)number >> bits);
/// <summary>
/// Performs an unsigned bitwise right shift with the specified number
/// </summary>
/// <param name="number">Number to operate on</param>
/// <param name="bits">Amount of bits to shift</param>
/// <returns>The resulting number from the shift operation</returns>
public static long URShift(long number, int bits) => (long)((ulong)number >> bits);
public static void SetSize(this List<byte> list, int count)
{
if (count > list.Count)
{
// Ensure the list only needs to grow once
list.Capacity = count;
for (var i = list.Count; i < count; i++)
{
list.Add(0x0);
}
}
else
{
list.RemoveRange(count, list.Count - count);
}
}
public static void ForEach<T>(this IEnumerable<T> items, Action<T> action)
{
foreach (var item in items)
{
action(item);
}
}
public static IEnumerable<T> AsEnumerable<T>(this T item)
{
yield return item;
}
public static void Skip(this Stream source, long advanceAmount)
{
if (source.CanSeek)
{
source.Position += advanceAmount;
return;
}
using var readOnlySubStream = new IO.ReadOnlySubStream(source, advanceAmount);
readOnlySubStream.CopyTo(Stream.Null);
}
public static void Skip(this Stream source) => source.CopyTo(Stream.Null);
public static Task SkipAsync(this Stream source, CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
return source.CopyToAsync(Stream.Null);
}
public static DateTime DosDateToDateTime(ushort iDate, ushort iTime)
{
var year = (iDate / 512) + 1980;
var month = iDate % 512 / 32;
var day = iDate % 512 % 32;
var hour = iTime / 2048;
var minute = iTime % 2048 / 32;
var second = iTime % 2048 % 32 * 2;
if (iDate == ushort.MaxValue || month == 0 || day == 0)
{
year = 1980;
month = 1;
day = 1;
}
if (iTime == ushort.MaxValue)
{
hour = minute = second = 0;
}
DateTime dt;
try
{
dt = new DateTime(year, month, day, hour, minute, second, DateTimeKind.Local);
}
catch
{
dt = new DateTime();
}
return dt;
}
public static uint DateTimeToDosTime(this DateTime? dateTime)
{
if (dateTime is null)
{
return 0;
}
var localDateTime = dateTime.Value.ToLocalTime();
return (uint)(
(localDateTime.Second / 2)
| (localDateTime.Minute << 5)
| (localDateTime.Hour << 11)
| (localDateTime.Day << 16)
| (localDateTime.Month << 21)
| ((localDateTime.Year - 1980) << 25)
);
}
public static DateTime DosDateToDateTime(uint iTime) =>
DosDateToDateTime((ushort)(iTime / 65536), (ushort)(iTime % 65536));
/// <summary>
/// Convert Unix time value to a DateTime object.
/// </summary>
/// <param name="unixtime">The Unix time stamp you want to convert to DateTime.</param>
/// <returns>Returns a DateTime object that represents value of the Unix time.</returns>
public static DateTime UnixTimeToDateTime(long unixtime)
{
var sTime = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
return sTime.AddSeconds(unixtime);
}
public static long TransferTo(this Stream source, Stream destination, long maxLength)
{
var array = ArrayPool<byte>.Shared.Rent(TEMP_BUFFER_SIZE);
try
{
var maxReadSize = array.Length;
long total = 0;
var remaining = maxLength;
if (remaining < maxReadSize)
{
maxReadSize = (int)remaining;
}
while (ReadTransferBlock(source, array, maxReadSize, out var count))
{
destination.Write(array, 0, count);
total += count;
if (remaining - count < 0)
{
break;
}
remaining -= count;
if (remaining < maxReadSize)
{
maxReadSize = (int)remaining;
}
}
return total;
}
finally
{
ArrayPool<byte>.Shared.Return(array);
}
}
public static async Task<long> TransferToAsync(
this Stream source,
Stream destination,
long maxLength,
CancellationToken cancellationToken = default
)
{
var array = ArrayPool<byte>.Shared.Rent(TEMP_BUFFER_SIZE);
try
{
var maxReadSize = array.Length;
long total = 0;
var remaining = maxLength;
if (remaining < maxReadSize)
{
maxReadSize = (int)remaining;
}
while (
await ReadTransferBlockAsync(source, array, maxReadSize, cancellationToken)
.ConfigureAwait(false)
is var (success, count)
&& success
)
{
await destination
.WriteAsync(array, 0, count, cancellationToken)
.ConfigureAwait(false);
total += count;
if (remaining - count < 0)
{
break;
}
remaining -= count;
if (remaining < maxReadSize)
{
maxReadSize = (int)remaining;
}
}
return total;
}
finally
{
ArrayPool<byte>.Shared.Return(array);
}
}
private static bool ReadTransferBlock(Stream source, byte[] array, int maxSize, out int count)
{
var size = maxSize;
if (maxSize > array.Length)
{
size = array.Length;
}
count = source.Read(array, 0, size);
return count != 0;
}
private static async Task<(bool success, int count)> ReadTransferBlockAsync(
Stream source,
byte[] array,
int maxSize,
CancellationToken cancellationToken
)
{
var size = maxSize;
if (maxSize > array.Length)
{
size = array.Length;
}
var count = await source.ReadAsync(array, 0, size, cancellationToken).ConfigureAwait(false);
return (count != 0, count);
}
public static async Task SkipAsync(
this Stream source,
long advanceAmount,
CancellationToken cancellationToken = default
)
{
if (source.CanSeek)
{
source.Position += advanceAmount;
return;
}
var array = ArrayPool<byte>.Shared.Rent(TEMP_BUFFER_SIZE);
try
{
while (advanceAmount > 0)
{
var toRead = (int)Math.Min(array.Length, advanceAmount);
var read = await source
.ReadAsync(array, 0, toRead, cancellationToken)
.ConfigureAwait(false);
if (read <= 0)
{
break;
}
advanceAmount -= read;
}
}
finally
{
ArrayPool<byte>.Shared.Return(array);
}
}
#if NET60_OR_GREATER
public static bool ReadFully(this Stream stream, byte[] buffer)
{
try
{
stream.ReadExactly(buffer);
return true;
}
catch (EndOfStreamException)
{
return false;
}
}
public static bool ReadFully(this Stream stream, Span<byte> buffer)
{
try
{
stream.ReadExactly(buffer);
return true;
}
catch (EndOfStreamException)
{
return false;
}
}
#else
public static bool ReadFully(this Stream stream, byte[] buffer)
{
var total = 0;
int read;
while ((read = stream.Read(buffer, total, buffer.Length - total)) > 0)
{
total += read;
if (total >= buffer.Length)
{
return true;
}
}
return (total >= buffer.Length);
}
public static bool ReadFully(this Stream stream, Span<byte> buffer)
{
var total = 0;
int read;
while ((read = stream.Read(buffer.Slice(total, buffer.Length - total))) > 0)
{
total += read;
if (total >= buffer.Length)
{
return true;
}
}
return (total >= buffer.Length);
}
#endif
public static async Task<bool> ReadFullyAsync(
this Stream stream,
byte[] buffer,
CancellationToken cancellationToken = default
)
{
var total = 0;
int read;
while (
(
read = await stream
.ReadAsync(buffer, total, buffer.Length - total, cancellationToken)
.ConfigureAwait(false)
) > 0
)
{
total += read;
if (total >= buffer.Length)
{
return true;
}
}
return (total >= buffer.Length);
}
public static string TrimNulls(this string source) => source.Replace('\0', ' ').Trim();
/// <summary>
/// Swap the endianness of a UINT32
/// </summary>
/// <param name="number">The UINT32 you want to swap his endianness</param>
/// <returns>Return the new UINT32 in the other endianness format</returns>
public static uint SwapUINT32(uint number) =>
(number >> 24)
| ((number << 8) & 0x00FF0000)
| ((number >> 8) & 0x0000FF00)
| (number << 24);
/// <summary>
/// Insert a little endian UINT32 into a byte array
/// </summary>
/// <param name="buffer">The buffer to insert into</param>
/// <param name="number">The UINT32 to insert</param>
/// <param name="offset">Offset of the buffer to insert into</param>
public static void SetLittleUInt32(ref byte[] buffer, uint number, long offset)
{
buffer[offset] = (byte)(number);
buffer[offset + 1] = (byte)(number >> 8);
buffer[offset + 2] = (byte)(number >> 16);
buffer[offset + 3] = (byte)(number >> 24);
}
/// <summary>
/// Insert a big endian UINT32 into a byte array
/// </summary>
/// <param name="buffer">The buffer to insert into</param>
/// <param name="number">The UINT32 to insert</param>
/// <param name="offset">Offset of the buffer to insert into</param>
public static void SetBigUInt32(ref byte[] buffer, uint number, long offset)
{
buffer[offset] = (byte)(number >> 24);
buffer[offset + 1] = (byte)(number >> 16);
buffer[offset + 2] = (byte)(number >> 8);
buffer[offset + 3] = (byte)number;
}
public static string ReplaceInvalidFileNameChars(string fileName)
{
var sb = new StringBuilder(fileName.Length);
foreach (var c in fileName)
{
var newChar = invalidChars.Contains(c) ? '_' : c;
sb.Append(newChar);
}
return sb.ToString();
}
}