private SafeFileHandle OpenHandle(FileMode mode, FileShare share, FileOptions options)
{
// FileStream performs most of the general argument validation. We can assume here that the arguments
// are all checked and consistent (e.g. non-null-or-empty path; valid enums in mode, access, share, and options; etc.)
// Store the arguments
_mode = mode;
_options = options;
if (_useAsyncIO)
{
_asyncState = new AsyncState();
}
// Translate the arguments into arguments for an open call.
Interop.Sys.OpenFlags openFlags = PreOpenConfigurationFromOptions(mode, _access, share, options);
// If the file gets created a new, we'll select the permissions for it. Most Unix utilities by default use 666 (read and
// write for all), so we do the same (even though this doesn't match Windows, where by default it's possible to write out
// a file and then execute it). No matter what we choose, it'll be subject to the umask applied by the system, such that the
// actual permissions will typically be less than what we select here.
const Interop.Sys.Permissions OpenPermissions =
Interop.Sys.Permissions.S_IRUSR | Interop.Sys.Permissions.S_IWUSR |
Interop.Sys.Permissions.S_IRGRP | Interop.Sys.Permissions.S_IWGRP |
Interop.Sys.Permissions.S_IROTH | Interop.Sys.Permissions.S_IWOTH;
// Open the file and store the safe handle.
return(SafeFileHandle.Open(_path, openFlags, (int)OpenPermissions));
}
/// <summary>
/// Initializes a new instance of the <see cref="Microsoft.Win32.SafeHandles.SafeFileHandle" /> class with the specified path, creation mode, read/write and sharing permission, the access other SafeFileHandles can have to the same file, additional file options and the allocation size.
/// </summary>
/// <param name="path">A relative or absolute path for the file that the current <see cref="Microsoft.Win32.SafeHandles.SafeFileHandle" /> instance will encapsulate.</param>
/// <param name="mode">One of the enumeration values that determines how to open or create the file. The default value is <see cref="FileMode.Open" /></param>
/// <param name="access">A bitwise combination of the enumeration values that determines how the file can be accessed. The default value is <see cref="FileAccess.Read" /></param>
/// <param name="share">A bitwise combination of the enumeration values that determines how the file will be shared by processes. The default value is <see cref="FileShare.Read" />.</param>
/// <param name="preallocationSize">The initial allocation size in bytes for the file. A positive value is effective only when a regular file is being created, overwritten, or replaced.
/// Negative values are not allowed. In other cases (including the default 0 value), it's ignored.</param>
/// <param name="options">An object that describes optional <see cref="Microsoft.Win32.SafeHandles.SafeFileHandle" /> parameters to use.</param>
/// <exception cref="T:System.ArgumentNullException"><paramref name="path" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentException"><paramref name="path" /> is an empty string (""), contains only white space, or contains one or more invalid characters.
/// -or-
/// <paramref name="path" /> refers to a non-file device, such as <c>CON:</c>, <c>COM1:</c>, <c>LPT1:</c>, etc. in an NTFS environment.</exception>
/// <exception cref="T:System.NotSupportedException"><paramref name="path" /> refers to a non-file device, such as <c>CON:</c>, <c>COM1:</c>, <c>LPT1:</c>, etc. in a non-NTFS environment.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException"><paramref name="preallocationSize" /> is negative.
/// -or-
/// <paramref name="mode" />, <paramref name="access" />, or <paramref name="share" /> contain an invalid value.</exception>
/// <exception cref="T:System.IO.FileNotFoundException">The file cannot be found, such as when <paramref name="mode" /> is <see cref="FileMode.Truncate" /> or <see cref="FileMode.Open" />, and the file specified by <paramref name="path" /> does not exist. The file must already exist in these modes.</exception>
/// <exception cref="T:System.IO.IOException">An I/O error, such as specifying <see cref="FileMode.CreateNew" /> when the file specified by <paramref name="path" /> already exists, occurred.
/// -or-
/// The disk was full (when <paramref name="preallocationSize" /> was provided and <paramref name="path" /> was pointing to a regular file).
/// -or-
/// The file was too large (when <paramref name="preallocationSize" /> was provided and <paramref name="path" /> was pointing to a regular file).</exception>
/// <exception cref="T:System.Security.SecurityException">The caller does not have the required permission.</exception>
/// <exception cref="T:System.IO.DirectoryNotFoundException">The specified path is invalid, such as being on an unmapped drive.</exception>
/// <exception cref="T:System.UnauthorizedAccessException">The <paramref name="access" /> requested is not permitted by the operating system for the specified <paramref name="path" />, such as when <paramref name="access" /> is <see cref="FileAccess.Write" /> or <see cref="FileAccess.ReadWrite" /> and the file or directory is set for read-only access.
/// -or-
/// <see cref="F:System.IO.FileOptions.Encrypted" /> is specified for <paramref name="options" />, but file encryption is not supported on the current platform.</exception>
/// <exception cref="T:System.IO.PathTooLongException">The specified path, file name, or both exceed the system-defined maximum length. </exception>
public static SafeFileHandle OpenHandle(string path, FileMode mode = FileMode.Open, FileAccess access = FileAccess.Read,
FileShare share = FileShare.Read, FileOptions options = FileOptions.None, long preallocationSize = 0)
{
Strategies.FileStreamHelpers.ValidateArguments(path, mode, access, share, bufferSize: 0, options, preallocationSize);
return(SafeFileHandle.Open(Path.GetFullPath(path), mode, access, share, options, preallocationSize));
}
private SafeFileHandle OpenHandle(FileMode mode, FileShare share, FileOptions options)
{
// FileStream performs most of the general argument validation. We can assume here that the arguments
// are all checked and consistent (e.g. non-null-or-empty path; valid enums in mode, access, share, and options; etc.)
// Store the arguments
_mode = mode;
_options = options;
if (_useAsyncIO)
{
_asyncState = new AsyncState();
}
// Translate the arguments into arguments for an open call.
Interop.Sys.OpenFlags openFlags = PreOpenConfigurationFromOptions(mode, _access, options); // FileShare currently ignored
// If the file gets created a new, we'll select the permissions for it. Most utilities by default use 666 (read and
// write for all). However, on Windows it's possible to write out a file and then execute it. To maintain that similarity,
// we use 766, so that in addition the user has execute privileges. No matter what we choose, it'll be subject to the umask
// applied by the system, such that the actual permissions will typically be less than what we select here.
const Interop.Sys.Permissions openPermissions =
Interop.Sys.Permissions.S_IRWXU |
Interop.Sys.Permissions.S_IRGRP | Interop.Sys.Permissions.S_IWGRP |
Interop.Sys.Permissions.S_IROTH | Interop.Sys.Permissions.S_IWOTH;
// Open the file and store the safe handle.
return(SafeFileHandle.Open(_path, openFlags, (int)openPermissions));
}
public static void CopyFile(string sourceFullPath, string destFullPath, bool overwrite)
{
long fileLength;
UnixFileMode filePermissions;
using SafeFileHandle src = SafeFileHandle.OpenReadOnly(sourceFullPath, FileOptions.None, out fileLength, out filePermissions);
using SafeFileHandle dst = SafeFileHandle.Open(destFullPath, overwrite ? FileMode.Create : FileMode.CreateNew,
FileAccess.ReadWrite, FileShare.None, FileOptions.None, preallocationSize: 0, filePermissions,
CreateOpenException);
Interop.CheckIo(Interop.Sys.CopyFile(src, dst, fileLength));
public static void CopyFile(string sourceFullPath, string destFullPath, bool overwrite)
{
long fileLength;
Interop.Sys.Permissions filePermissions;
using SafeFileHandle src = SafeFileHandle.OpenReadOnly(sourceFullPath, FileOptions.None, out fileLength, out filePermissions);
using SafeFileHandle dst = SafeFileHandle.Open(destFullPath, overwrite ? FileMode.Create : FileMode.CreateNew,
FileAccess.ReadWrite, FileShare.None, FileOptions.None, preallocationSize: 0, openPermissions: filePermissions,
(Interop.ErrorInfo error, Interop.Sys.OpenFlags flags, string path) => CreateOpenException(error, flags, path));
Interop.CheckIo(Interop.Sys.CopyFile(src, dst, fileLength));
/// <summary>Initializes a stream for reading or writing a Unix file.</summary>
/// <param name="path">The path to the file.</param>
/// <param name="mode">How the file should be opened.</param>
/// <param name="access">Whether the file will be read, written, or both.</param>
/// <param name="share">What other access to the file should be allowed. This is currently ignored.</param>
/// <param name="bufferSize">The size of the buffer to use when buffering.</param>
/// <param name="options">Additional options for working with the file.</param>
internal UnixFileStream(String path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options, FileStream parent)
: base(parent)
{
// FileStream performs most of the general argument validation. We can assume here that the arguments
// are all checked and consistent (e.g. non-null-or-empty path; valid enums in mode, access, share, and options; etc.)
// Store the arguments
_path = path;
_access = access;
_mode = mode;
_options = options;
_bufferLength = bufferSize;
_useAsyncIO = (options & FileOptions.Asynchronous) != 0;
// Translate the arguments into arguments for an open call
Interop.libc.OpenFlags openFlags = PreOpenConfigurationFromOptions(mode, access, options); // FileShare currently ignored
Interop.libc.Permissions openPermissions = Interop.libc.Permissions.S_IRWXU; // creator has read/write/execute permissions; no permissions for anyone else
// Open the file and store the safe handle. Subsequent code in this method expects the safe handle to be initialized.
_fileHandle = SafeFileHandle.Open(path, openFlags, (int)openPermissions);
_fileHandle.IsAsync = _useAsyncIO;
// Lock the file if requested via FileShare. This is only advisory locking. FileShare.None implies an exclusive
// lock on the file and all other modes use a shared lock. While this is not as granular as Windows, not mandatory,
// and not atomic with file opening, it's better than nothing.
try
{
Interop.libc.LockOperations lockOperation = (share == FileShare.None) ? Interop.libc.LockOperations.LOCK_EX : Interop.libc.LockOperations.LOCK_SH;
SysCall <Interop.libc.LockOperations, int>((fd, op, _) => Interop.libc.flock(fd, op), lockOperation | Interop.libc.LockOperations.LOCK_NB);
}
catch
{
_fileHandle.Dispose();
throw;
}
// Support additional options after the file has been opened.
// These provide hints around how the file will be accessed.
Interop.libc.Advice fadv =
_options == FileOptions.RandomAccess ? Interop.libc.Advice.POSIX_FADV_RANDOM :
_options == FileOptions.SequentialScan ? Interop.libc.Advice.POSIX_FADV_SEQUENTIAL :
0;
if (fadv != 0)
{
SysCall <Interop.libc.Advice, int>((fd, advice, _) => Interop.libc.posix_fadvise(fd, 0, 0, advice), fadv);
}
// Jump to the end of the file if opened as Append.
if (_mode == FileMode.Append)
{
_appendStart = SeekCore(0, SeekOrigin.End);
}
}
