using Unosquare.Swan;
using System;
using System.Runtime.InteropServices;
using System.Text;
namespace Unosquare.RaspberryIO.Native {
///
/// Provides standard libc calls using platform-invoke
///
internal static class Standard {
internal const String LibCLibrary = "libc";
#region LibC Calls
///
/// Strerrors the specified error.
///
/// The error.
///
public static String Strerror(Int32 error) {
if(!Runtime.IsUsingMonoRuntime) {
return StrError(error);
}
try {
StringBuilder buffer = new StringBuilder(256);
Int32 result = Strerror(error, buffer, (UInt64)buffer.Capacity);
return (result != -1) ? buffer.ToString() : null;
} catch(EntryPointNotFoundException) {
return null;
}
}
///
/// Changes file permissions on a Unix file system
///
/// The filename.
/// The mode.
/// The result
[DllImport(LibCLibrary, EntryPoint = "chmod", SetLastError = true)]
public static extern Int32 Chmod(String filename, UInt32 mode);
///
/// Converts a string to a 32 bit integer. Use endpointer as IntPtr.Zero
///
/// The number string.
/// The end pointer.
/// The number base.
/// The result
[DllImport(LibCLibrary, EntryPoint = "strtol", SetLastError = true)]
public static extern Int32 StringToInteger(String numberString, IntPtr endPointer, Int32 numberBase);
///
/// The write() function attempts to write nbytes from buffer to the file associated with handle. On text files, it expands each LF to a CR/LF.
/// The function returns the number of bytes written to the file. A return value of -1 indicates an error, with errno set appropriately.
///
/// The fd.
/// The buffer.
/// The count.
/// The result
[DllImport(LibCLibrary, EntryPoint = "write", SetLastError = true)]
public static extern Int32 Write(Int32 fd, Byte[] buffer, Int32 count);
///
/// Fills in the structure with information about the system.
///
/// The name.
/// The result
[DllImport(LibCLibrary, EntryPoint = "uname", SetLastError = true)]
public static extern Int32 Uname(out SystemName name);
[DllImport(LibCLibrary, EntryPoint = "strerror", SetLastError = true)]
private static extern String StrError(Int32 errnum);
[DllImport("MonoPosixHelper", EntryPoint = "Mono_Posix_Syscall_strerror_r", SetLastError = true)]
private static extern Int32 Strerror(Int32 error, [Out] StringBuilder buffer, UInt64 length);
#endregion
}
}