[Documentation("file(name: str[, mode: str]) -> file IO object\n\n"

+ "Open a file. The mode can be 'r', 'w' or 'a' for reading (default),\n"

+ "writing or appending. The file will be created if it doesn't exist\n"

+ "when opened for writing or appending; it will be truncated when\n"

+ "opened for writing. Add a '+' to the mode to allow simultaneous\n"

+ "reading and writing."

)]

[PythonType, DontMapIDisposableToContextManager]

public class FileIO : _RawIOBase, IDisposable, IWeakReferenceable, ICodeFormattable, IDynamicMetaObjectProvider {

#region Fields and constructors

private static readonly int DEFAULT_BUF_SIZE = 32;

internal Stream _readStream;

private Stream _writeStream;

private bool _closed, _closefd;

private WeakRefTracker _tracker;

private PythonContext _context;

public object name;

public FileIO(CodeContext/*!*/ context, int fd, [DefaultParameterValue("r")]string mode, [DefaultParameterValue(true)]bool closefd)

: base(context) {

if (fd < 0) {

throw PythonOps.ValueError("fd must be >= 0");

}

PythonContext pc = context.LanguageContext;

_context = pc;

switch (StandardizeMode(mode)) {

case "r": this.mode = "rb"; break;

case "w": this.mode = "wb"; break;

case "a": this.mode = "w"; break;

case "r+":

case "+r": this.mode = "rb+"; break;

case "w+":

case "+w": this.mode = "rb+"; break;

case "a+":

case "+a": this.mode = "r+"; break;

default:

BadMode(mode);

break;

}

if (pc.FileManager.TryGetFileFromId(pc, fd, out PythonFile pf)) {

name = (object)pf.name ?? fd;

_readStream = pf._stream;

_writeStream = pf._stream;

} else if (pc.FileManager.TryGetObjectFromId(pc, fd, out object fileObj)) {

if (fileObj is FileIO file) {

name = file.name ?? fd;

_readStream = file._readStream;

_writeStream = file._writeStream;

} else if (fileObj is Stream stream) {

name = fd;

_readStream = stream;

_writeStream = stream;

}

}

_closefd = closefd;

}

public FileIO(CodeContext/*!*/ context, string name, [DefaultParameterValue("r")]string mode, [DefaultParameterValue(true)]bool closefd)

: base(context) {

if (!closefd) {

throw PythonOps.ValueError("Cannot use closefd=False with file name");

}

_closefd = true;

this.name = name;

PlatformAdaptationLayer pal = context.LanguageContext.DomainManager.Platform;

switch (StandardizeMode(mode)) {

case "r":

_readStream = _writeStream = OpenFile(context, pal, name, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);

this.mode = "rb";

break;

case "w":

_readStream = _writeStream = OpenFile(context, pal, name, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);

this.mode = "wb";

break;

case "a":

_readStream = _writeStream = OpenFile(context, pal, name, FileMode.Append, FileAccess.Write, FileShare.ReadWrite);

_readStream.Seek(0L, SeekOrigin.End);

this.mode = "ab";

break;

case "r+":

case "+r":

_readStream = _writeStream = OpenFile(context, pal, name, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);

this.mode = "rb+";

break;

case "w+":

case "+w":

_readStream = _writeStream = OpenFile(context, pal, name, FileMode.Create, FileAccess.ReadWrite, FileShare.ReadWrite);

this.mode = "rb+";

break;

case "a+":

case "+a":

_readStream = OpenFile(context, pal, name, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);

_writeStream = OpenFile(context, pal, name, FileMode.Append, FileAccess.Write, FileShare.ReadWrite);

_readStream.Seek(0L, SeekOrigin.End);

_writeStream.Seek(0L, SeekOrigin.End);

this.mode = "ab+";

break;

default:

BadMode(mode);

break;

}

_context = context.LanguageContext;

}

/// <summary>

/// Remove all 'b's from mode string to simplify parsing

/// </summary>

private static string StandardizeMode(string mode) {

int index = mode.IndexOf('b');

if (index == mode.Length - 1) {

mode = mode.Substring(0, index);

} else if (index >= 0) {

StringBuilder sb = new StringBuilder(mode.Substring(0, index), mode.Length - 1);

for (int pos = index + 1; pos < mode.Length; pos++) {

if (mode[pos] != 'b') {

sb.Append(mode[pos]);

}

}

mode = sb.ToString();

}

return mode;

}

private static void BadMode(string mode) {

bool foundMode = false, foundPlus = false;

foreach (char c in mode) {

switch (c) {

case 'r':

case 'w':

case 'a':

if (foundMode) {

throw PythonOps.ValueError("Must have exactly one of read/write/append mode");

} else {

foundMode = true;

continue;

}

case '+':

if (foundPlus) {

throw PythonOps.ValueError("Must have exactly one of read/write/append mode");

} else {

foundPlus = true;

continue;

}

case 'b':

// any number of 'b's is acceptable

continue;

default:

throw PythonOps.ValueError("invalid mode: {0}", mode);

}

}

throw PythonOps.ValueError("Must have exactly one of read/write/append mode");

}

#endregion

#region Public API

[Documentation("close() -> None. Close the file.\n\n"

+ "A closed file cannot be used for further I/O operations. close() may be"

+ "called more than once without error. Changes the fileno to -1."

)]

public override void close(CodeContext/*!*/ context) {

if (_closed) {

return;

}

flush(context);

_closed = true;

if (_closefd) {

_readStream.Dispose();

if (!object.ReferenceEquals(_readStream, _writeStream)) {

_writeStream.Dispose();

}

}

PythonFileManager myManager = _context.RawFileManager;

if (myManager != null) {

myManager.Remove(this);

}

}

[Documentation("True if the file is closed")]

public override bool closed {

get {

return _closed;

}

}

public bool closefd {

get {

return _closefd;

}

}

[Documentation("fileno() -> int. \"file descriptor\".\n\n"

+ "This is needed for lower-level file interfaces, such as the fcntl module."

)]

public override int fileno(CodeContext/*!*/ context) {

_checkClosed();

return _context.FileManager.GetOrAssignIdForObject(this);

}

[Documentation("Flush write buffers, if applicable.\n\n"

+ "This is not implemented for read-only and non-blocking streams.\n"

)]

public override void flush(CodeContext/*!*/ context) {

_checkClosed();

if (_writeStream != null) {

_writeStream.Flush();

}

}

[Documentation("isatty() -> bool. True if the file is connected to a tty device.")]

public override bool isatty(CodeContext/*!*/ context) {

_checkClosed();

return false;

}

[Documentation("String giving the file mode")]

public string mode { get; }

[Documentation("read(size: int) -> bytes. read at most size bytes, returned as bytes.\n\n"

+ "Only makes one system call, so less data may be returned than requested\n"

+ "In non-blocking mode, returns None if no data is available.\n"

+ "On end-of-file, returns ''."

)]

public override object read(CodeContext/*!*/ context, [DefaultParameterValue(null)]object size) {

int sizeInt = GetInt(size, -1);

if (sizeInt < 0) {

return readall();

}

EnsureReadable();

byte[] buffer = new byte[sizeInt];

int bytesRead = _readStream.Read(buffer, 0, sizeInt);

Array.Resize(ref buffer, bytesRead);

return Bytes.Make(buffer);

}

[Documentation("readable() -> bool. True if file was opened in a read mode.")]

public override bool readable(CodeContext/*!*/ context) {

_checkClosed();

return _readStream.CanRead;

}

[Documentation("readall() -> bytes. read all data from the file, returned as bytes.\n\n"

+ "In non-blocking mode, returns as much as is immediately available,\n"

+ "or None if no data is available. On end-of-file, returns ''."

)]

public Bytes readall() {

EnsureReadable();

int bufSize = DEFAULT_BUF_SIZE;

byte[] buffer = new byte[bufSize];

int bytesRead = _readStream.Read(buffer, 0, bufSize);

for (; bytesRead == bufSize; bufSize *= 2) {

Array.Resize(ref buffer, bufSize * 2);

bytesRead += _readStream.Read(buffer, bufSize, bufSize);

}

Array.Resize(ref buffer, bytesRead);

return Bytes.Make(buffer);

}

[Documentation("readinto() -> Same as RawIOBase.readinto().")]

public BigInteger readinto([NotNull]ArrayModule.array buffer) {

EnsureReadable();

return (int)buffer.FromStream(_readStream, 0, buffer.__len__() * buffer.itemsize);

}

public BigInteger readinto([NotNull]ByteArray buffer) {

EnsureReadable();

for (int i = 0; i < buffer.Count; i++) {

int b = _readStream.ReadByte();

if (b == -1) return i - 1;

buffer[i] = (byte)b;

}

return buffer.Count;

}

public BigInteger readinto([NotNull]PythonBuffer buffer) {

EnsureReadable();

throw PythonOps.TypeError("buffer is read-only");

}

public override BigInteger readinto(CodeContext/*!*/ context, object buf) {

ByteArray bytes = buf as ByteArray;

if (bytes != null) {

return readinto(bytes);

}

ArrayModule.array arr = buf as ArrayModule.array;

if (arr != null) {

return readinto(bytes);

};

EnsureReadable();

throw PythonOps.TypeError(

"argument 1 must be read/write buffer, not {0}",

DynamicHelpers.GetPythonType(buf).Name

);

}

[Documentation("seek(offset: int[, whence: int]) -> None. Move to new file position.\n\n"

+ "Argument offset is a byte count. Optional argument whence defaults to\n"

+ "0 (offset from start of file, offset should be >= 0); other values are 1\n"

+ "(move relative to current position, positive or negative), and 2 (move\n"

+ "relative to end of file, usually negative, although many platforms allow\n"

+ "seeking beyond the end of a file).\n"

+ "Note that not all file objects are seekable."

)]

public override BigInteger seek(CodeContext/*!*/ context, BigInteger offset, [Optional]object whence) {

_checkClosed();

return _readStream.Seek((long)offset, (SeekOrigin)GetInt(whence));

}

public BigInteger seek(double offset, [Optional]object whence) {

_checkClosed();

throw PythonOps.TypeError("an integer is required");

}

[Documentation("seekable() -> bool. True if file supports random-access.")]

public override bool seekable(CodeContext/*!*/ context) {

_checkClosed();

return _readStream.CanSeek;

}

[Documentation("tell() -> int. Current file position")]

public override BigInteger tell(CodeContext/*!*/ context) {

_checkClosed();

return _readStream.Position;

}

public BigInteger truncate(BigInteger size) {

EnsureWritable();

long pos = _readStream.Position;

_writeStream.SetLength((long)size);

_readStream.Seek(pos, SeekOrigin.Begin);

return size;

}

public BigInteger truncate(double size) {

EnsureWritable();

throw PythonOps.TypeError("an integer is required");

}

[Documentation("truncate([size: int]) -> None. Truncate the file to at most size bytes.\n\n"

+ "Size defaults to the current file position, as returned by tell()."

+ "The current file position is changed to the value of size."

)]

public override BigInteger truncate(CodeContext/*!*/ context, [DefaultParameterValue(null)]object pos) {

if (pos == null) {

return truncate(tell(context));

}

BigInteger bi;

if (TryGetBigInt(pos, out bi)) {

return truncate(bi);

}

EnsureWritable();

throw PythonOps.TypeError("an integer is required");

}

[Documentation("writable() -> bool. True if file was opened in a write mode.")]

public override bool writable(CodeContext/*!*/ context) {

_checkClosed();

return _writeStream.CanWrite;

}

private BigInteger write([NotNull]byte[] b) {

EnsureWritable();

_writeStream.Write(b, 0, b.Length);

SeekToEnd();

return b.Length;

}

private BigInteger write([NotNull]Bytes b) {

return write(b._bytes);

}

private BigInteger write([NotNull]ICollection<byte> b) {

EnsureWritable();

int len = b.Count;

byte[] bytes = new byte[len];

b.CopyTo(bytes, 0);

_writeStream.Write(bytes, 0, len);

SeekToEnd();

return len;

}

private BigInteger write([NotNull]string s) {

return write(s.MakeByteArray());

}

[Documentation("write(b: bytes) -> int. Write bytes b to file, return number written.\n\n"

+ "Only makes one system call, so not all the data may be written.\n"

+ "The number of bytes actually written is returned."

)]

public override BigInteger write(CodeContext/*!*/ context, object b) {

byte[] bArray = b as byte[];

if (bArray != null) {

return write(bArray);

}

Bytes bBytes = b as Bytes;

if (bBytes != null) {

return write(bBytes);

}

ArrayModule.array bPythonArray = b as ArrayModule.array;

if (bPythonArray != null) {

return write(bPythonArray.ToByteArray());

}

ICollection<byte> bCollection = b as ICollection<byte>;

if (bCollection != null) {

return write(bCollection);

}

EnsureWritable();

throw PythonOps.TypeError("expected a readable buffer object");

}

#endregion

#region ICodeFormattable Members

public string __repr__(CodeContext/*!*/ context) {

return string.Format("<_io.FileIO name={0} mode='{1}'>", PythonOps.Repr(context, name), mode);

}

#endregion

#region IDisposable methods

void IDisposable.Dispose() { }

#endregion

#region IWeakReferenceable Members

WeakRefTracker IWeakReferenceable.GetWeakRef() {

return _tracker;

}

bool IWeakReferenceable.SetWeakRef(WeakRefTracker value) {

_tracker = value;

return true;

}

void IWeakReferenceable.SetFinalizer(WeakRefTracker value) {

((IWeakReferenceable)this).SetWeakRef(value);

}

#endregion

#region IDynamicMetaObjectProvider Members

DynamicMetaObject IDynamicMetaObjectProvider.GetMetaObject(Expression parameter) {

return new MetaExpandable<FileIO>(parameter, this);

}

#endregion

#region Private implementation details

private static Stream OpenFile(CodeContext/*!*/ context, PlatformAdaptationLayer pal, string name, FileMode fileMode, FileAccess fileAccess, FileShare fileShare) {

try {

return pal.OpenInputFileStream(name, fileMode, fileAccess, fileShare);

} catch (UnauthorizedAccessException e) {

throw PythonFile.ToIoException(context, name, e);

} catch (IOException e) {

PythonFile.AddFilename(context, name, e);

throw;

}

}

private void EnsureReadable() {

_checkClosed();

_checkReadable("File not open for reading");

}

private void EnsureWritable() {

_checkClosed();

_checkWritable("File not open for writing");

}

private void SeekToEnd() {

if (!object.ReferenceEquals(_readStream, _writeStream)) {

_readStream.Seek(_writeStream.Position, SeekOrigin.Begin);

}

}

#endregion

}