/// <summary>
/// Writes a string with the given encoding to the given offset of the file
/// </summary>
/// <param name="index">Index of the file to write</param>
/// <param name="e">The encoding to use</param>
/// <param name="value">The string to write. The entire string will be written with an ending null character.</param>
public static async Task WriteNullTerminatedStringAsync(this IWriteOnlyBinaryDataAccessor accessor, long index, Encoding e, string value)
{
var nullChar = e.GetBytes(new[] { Convert.ToChar(0) });
var data = e.GetBytes(value);
await accessor.WriteAsync(index, data.Length, data);
await accessor.WriteAsync(index + data.Length, nullChar.Length, nullChar);
}
/// <summary>
/// Writes the current state of the NCCH partition to the given binary data accessor
/// </summary>
/// <param name="data">Data accessor to receive the binary data</param>
/// <returns>A long representing the total length of data written</returns>
public async Task <long> WriteBinary(IWriteOnlyBinaryDataAccessor data)
{
// Get the data
var exheader = ExHeader?.ToByteArray();
var plainRegion = !string.IsNullOrEmpty(PlainRegion) ? Encoding.ASCII.GetBytes(PlainRegion) : null;
var plainRegionOffset = 0;
var logoRegionOffset = 0;
var exeFs = ExeFs?.ToByteArray();
var exeFsOffset = 0;
var romFs = RomFs?.Data;
var romFsOffset = 0;
// Write the data
var offset = 0x200; // Skip the header, write it last
if (exheader != null)
{
await data.WriteAsync(offset, exheader);
offset += exheader.Length;
}
if (plainRegion != null)
{
plainRegionOffset = offset;
await data.WriteAsync(offset, plainRegion);
offset += plainRegion.Length;
var padding = new byte[0x200 - plainRegion.Length % 0x200];
await data.WriteAsync(offset, padding);
offset += padding.Length;
}
if (Logo != null)
{
logoRegionOffset = offset;
await data.WriteAsync(offset, Logo);
offset += Logo.Length;
var padding = new byte[0x200 - Logo.Length % 0x200];
await data.WriteAsync(offset, padding);
offset += padding.Length;
}
if (exeFs != null)
{
exeFsOffset = offset;
await data.WriteAsync(offset, exeFs);
offset += exeFs.Length;
var padding = new byte[0x200 - exeFs.Length % 0x200];
await data.WriteAsync(offset, padding);
offset += padding.Length;
}
if (romFs != null)
{
romFsOffset = offset;
const int bufferSize = 1024 * 1024;
for (int i = 0; i < romFs.Length; i += bufferSize)
{
int length = (int)Math.Min(bufferSize, romFs.Length - i);
var block = await romFs.ReadArrayAsync(i, length);
await data.WriteAsync(offset, block);
offset += length;
}
var padding = new byte[0x200 - romFs.Length % 0x200];
await data.WriteAsync(offset, padding);
offset += padding.Length;
}
// Create a new header
using var sha = SHA256.Create();
var header = NcchHeader.Copy(this.Header);
header.Signature = new byte[0x100]; // We lack the 3DS's private key, so leave out the signature
header.ContentSize = (offset + MediaUnitSize - 1) / MediaUnitSize; // offset/MediaUnitSize, but rounding up
header.ContentLockSeedHash = 0; // Unknown, left blank by SciresM's 3DS Builder
if (Logo != null)
{
header.LogoRegionHash = sha.ComputeHash(Logo);
}
else
{
header.LogoRegionHash = new byte[0x20];
}
if (exheader != null)
{
header.ExHeaderHash = NcchExtendedHeader.GetSuperblockHash(sha, exheader);
header.ExHeaderSize = NcchExtendedHeader.ExHeaderDataSize;
}
else
{
header.ExHeaderHash = new byte[0x20];
header.ExHeaderSize = 0;
}
header.PlainRegionOffset = (plainRegionOffset + MediaUnitSize - 1) / MediaUnitSize;
header.PlainRegionSize = ((plainRegion?.Length ?? 0) + MediaUnitSize - 1) / MediaUnitSize;
header.LogoRegionOffset = (logoRegionOffset + MediaUnitSize - 1) / MediaUnitSize;
header.LogoRegionSize = ((Logo?.Length ?? 0) + MediaUnitSize - 1) / MediaUnitSize;
header.ExeFsOffset = (exeFsOffset + MediaUnitSize - 1) / MediaUnitSize;
header.ExeFsSize = ((exeFs?.Length ?? 0) + MediaUnitSize - 1) / MediaUnitSize;
header.ExeFsHashRegionSize = 1; // Static 0x200 for exefs superblock
header.RomFsOffset = (romFsOffset + MediaUnitSize - 1) / MediaUnitSize;
header.RomFsSize = ((int)(romFs?.Length ?? 0) + MediaUnitSize - 1) / MediaUnitSize;
header.RomFsHashRegionSize = ((RomFs?.Header?.MasterHashSize ?? 0) + MediaUnitSize - 1) / MediaUnitSize;
header.ExeFsSuperblockHash = ExeFs?.GetSuperblockHash() ?? new byte[0x20];
header.RomFsSuperblockHash = RomFs != null ? await RomFs.GetSuperblockHash(sha, romFs, RomFs.Header) : new byte[0x20];
var headerData = await header.ToBinary().ReadArrayAsync();
await data.WriteAsync(0, headerData);
return(offset);
}
/// <summary>
/// Writes a signed 16 bit little endian integer
/// </summary>
/// <param name="offset">Offset of the integer to write.</param>
/// <param name="value">The integer to write</param>
public static async Task WriteInt16Async(this IWriteOnlyBinaryDataAccessor accessor, long offset, Int16 value)
{
await accessor.WriteAsync(offset, 2, BitConverter.GetBytes(value));
}
/// <summary>
/// Writes all of the given data to the desired index
/// </summary>
/// <param name="index">Index of the data to write</param>
/// <param name="value">Data to write</param>
public static async Task WriteAsync(this IWriteOnlyBinaryDataAccessor accessor, long index, byte[] value)
{
await accessor.WriteAsync(index, value.Length, value);
}
/// <summary>
/// Writes a string with the given encoding to the given offset of the file
/// </summary>
/// <param name="index">Index of the file to write</param>
/// <param name="e">The encoding to use</param>
/// <param name="value">The string to write. The entire string will be written without an ending null character.</param>
public static async Task WriteStringAsync(this IWriteOnlyBinaryDataAccessor accessor, long index, Encoding e, string value)
{
await accessor.WriteAsync(index, e.GetBytes(value));
}