/// <summary>
/// Helper for making system calls that involve the stream's file descriptor.
/// System calls are expected to return greather than or equal to zero on success,
/// and less than zero on failure. In the case of failure, errno is expected to
/// be set to the relevant error code.
/// </summary>
/// <param name="sysCall">A delegate that invokes the system call.</param>
/// <param name="arg1">The first argument to be passed to the system call, after the file descriptor.</param>
/// <param name="arg2">The second argument to be passed to the system call.</param>
/// <returns>The return value of the system call.</returns>
/// <remarks>
/// Arguments are expected to be passed via <paramref name="arg1"/> and <paramref name="arg2"/>
/// so as to avoid delegate and closure allocations at the call sites.
/// </remarks>
private static long SysCall(
SafePipeHandle handle,
Func<int, IntPtr, int, long> sysCall,
IntPtr arg1 = default(IntPtr), int arg2 = default(int))
{
bool gotRefOnHandle = false;
try
{
// Get the file descriptor from the handle. We increment the ref count to help
// ensure it's not closed out from under us.
handle.DangerousAddRef(ref gotRefOnHandle);
Debug.Assert(gotRefOnHandle);
int fd = (int)handle.DangerousGetHandle();
Debug.Assert(fd >= 0);
long result;
while (Interop.CheckIo(result = sysCall(fd, arg1, arg2))) ;
return result;
}
finally
{
if (gotRefOnHandle)
{
handle.DangerousRelease();
}
}
}
/// <summary>
/// Helper for making system calls that involve the stream's file descriptor.
/// System calls are expected to return greather than or equal to zero on success,
/// and less than zero on failure. In the case of failure, errno is expected to
/// be set to the relevant error code.
/// </summary>
/// <param name="sysCall">A delegate that invokes the system call.</param>
/// <param name="arg1">The first argument to be passed to the system call, after the file descriptor.</param>
/// <param name="arg2">The second argument to be passed to the system call.</param>
/// <param name="arg3">The third argument to be passed to the system call.</param>
/// <returns>The return value of the system call.</returns>
/// <remarks>
/// Arguments are expected to be passed via <paramref name="arg1"/> and <paramref name="arg2"/>
/// so as to avoid delegate and closure allocations at the call sites.
/// </remarks>
private long SysCall(
SafePipeHandle handle,
Func<int, IntPtr, int, IntPtr, long> sysCall,
IntPtr arg1 = default(IntPtr), int arg2 = default(int), IntPtr arg3 = default(IntPtr))
{
bool gotRefOnHandle = false;
try
{
// Get the file descriptor from the handle. We increment the ref count to help
// ensure it's not closed out from under us.
handle.DangerousAddRef(ref gotRefOnHandle);
Debug.Assert(gotRefOnHandle);
int fd = (int)handle.DangerousGetHandle();
Debug.Assert(fd >= 0);
while (true)
{
long result = sysCall(fd, arg1, arg2, arg3);
if (result == -1)
{
Interop.ErrorInfo errorInfo = Interop.Sys.GetLastErrorInfo();
if (errorInfo.Error == Interop.Error.EINTR)
continue;
if (errorInfo.Error == Interop.Error.EPIPE)
State = PipeState.Broken;
throw Interop.GetExceptionForIoErrno(errorInfo);
}
return result;
}
}
finally
{
if (gotRefOnHandle)
{
handle.DangerousRelease();
}
}
}