Capy64/Capy64/Runtime/Objects/FileHandle.cs
2023-02-16 18:43:10 +01:00

355 lines
8 KiB
C#

// This file is part of Capy64 - https://github.com/Capy64/Capy64
// Copyright 2023 Alessandro "AlexDevs" Proto
//
// Licensed under the Apache License, Version 2.0 (the "License").
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
using Capy64.API;
using KeraLua;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Capy64.Runtime.Objects;
public class FileHandle : IComponent
{
public const string ObjectType = "file";
private static LuaRegister[] Methods = new LuaRegister[]
{
new()
{
name = "read",
function = L_Read,
},
new()
{
name = "write",
function = L_Write,
},
new()
{
name = "lines",
function = L_Lines,
},
new()
{
name = "flush",
function = L_Flush,
},
new()
{
name = "seek",
function = L_Seek,
},
new()
{
name = "close",
function = L_Close,
},
new(),
};
private static LuaRegister[] MetaMethods = new LuaRegister[]
{
new()
{
name = "__index",
},
new()
{
name = "__gc",
function = LM_GC,
},
new()
{
name = "__close",
function = LM_GC,
},
new()
{
name = "__tostring",
function = LM_ToString,
},
new(),
};
public void LuaInit(Lua L)
{
CreateMeta(L);
}
public static void CreateMeta(Lua L)
{
L.NewMetaTable(ObjectType);
L.SetFuncs(MetaMethods, 0);
L.NewLibTable(Methods);
L.SetFuncs(Methods, 0);
L.SetField(-2, "__index");
L.Pop(1);
}
private static char CheckMode(string mode)
{
var modes = "nlLa";
mode = mode.TrimStart('*');
if(string.IsNullOrEmpty(mode)) {
return '\0';
}
var i = modes.IndexOf(mode[0]);
if(i == -1)
return '\0';
return modes[i];
}
private static Stream ToStream(Lua L, bool gc = false)
{
return ObjectManager.ToObject<Stream>(L, 1, gc);
}
private static Stream CheckStream(Lua L, bool gc = false)
{
var obj = ObjectManager.CheckObject<Stream>(L, 1, ObjectType, gc);
if (obj is null)
{
L.Error("attempt to use a closed file");
return null;
}
return obj;
}
private static bool ReadNumber(Lua L, Stream stream)
{
return false;
}
private static bool ReadLine(Lua L, Stream stream, bool chop)
{
var buffer = new byte[stream.Length];
int i = 0;
int c = 0;
for (; i < stream.Length; i++)
{
c = stream.ReadByte();
if (c == -1 || c == '\n')
break;
buffer[i] = (byte)c;
}
if (!chop && c == '\n')
buffer[i++] = (byte)c;
Array.Resize(ref buffer, i);
L.PushBuffer(buffer);
return c == '\n' || L.RawLen(-1) > 0;
}
private static void ReadAll(Lua L, Stream stream)
{
var buffer = new byte[stream.Length];
var read = stream.Read(buffer, 0, buffer.Length);
Array.Resize(ref buffer, read);
L.PushBuffer(buffer);
}
private static bool ReadChars(Lua L, Stream stream, int n)
{
var buffer = new byte[n];
var read = stream.Read(buffer, 0, n);
Array.Resize(ref buffer, read);
L.PushBuffer(buffer);
return read != 0;
}
private static int L_Read(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = CheckStream(L);
if (!stream.CanRead)
{
L.PushNil();
L.PushString("Attempt to read from a write-only stream");
return 2;
}
var nargs = L.GetTop() - 1;
if (nargs == 0)
{
L.PushString("l");
}
bool success;
if (L.Type(2) == LuaType.Number)
{
success = ReadChars(L, stream, (int)L.ToNumber(2));
}
else
{
var p = L.CheckString(2);
var mode = CheckMode(p);
switch (mode)
{
case 'n':
success = ReadNumber(L, stream);
break;
case 'l':
success = ReadLine(L, stream, true);
break;
case 'L':
success = ReadLine(L, stream, false);
break;
case 'a':
ReadAll(L, stream);
success = true;
break;
default:
return L.ArgumentError(2, "invalid format");
}
}
if (!success)
{
L.Pop(1);
L.PushNil();
}
return 1;
}
private static int L_Write(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var nargs = L.GetTop();
var stream = CheckStream(L);
if (!stream.CanWrite)
{
L.PushNil();
L.PushString("Attempt to write to a read-only stream");
return 2;
}
for (int arg = 2; arg <= nargs; arg++)
{
if (L.Type(arg) == LuaType.Number)
{
stream.WriteByte((byte)L.ToNumber(arg));
}
else
{
var buffer = L.CheckBuffer(arg);
stream.Write(buffer);
}
}
return L.FileResult(1, null);
}
private static int L_Lines(IntPtr state)
{
return 0;
var L = Lua.FromIntPtr(state);
var maxargn = 250;
var n = L.GetTop() - 1;
var stream = CheckStream(L, false);
L.ArgumentCheck(n <= maxargn, maxargn + 2, "too many arguments");
L.PushCopy(1);
L.PushInteger(n);
L.PushBoolean(false);
L.Rotate(2, 3);
L.PushCClosure(null, 3 + n); // todo
return 1;
}
private static int L_Flush(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = CheckStream(L, false);
stream.Flush();
return 0;
}
private static int L_Seek(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = CheckStream(L, false);
var whence = L.CheckOption(2, "cur", new[]
{
"set", // begin 0
"cur", // current 1
"end", // end 2
null,
});
var offset = L.OptInteger(3, 0);
var newPosition = stream.Seek(offset, (SeekOrigin)whence);
L.PushInteger(newPosition);
return 1;
}
private static int L_Close(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = CheckStream(L, true);
stream.Close();
return 0;
}
private static unsafe int LM_ToString(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = ToStream(L);
if (stream is not null)
{
L.PushString("file ({0:X})", (ulong)&stream);
}
else
{
L.PushString("file (closed)");
}
return 1;
}
private static int LM_GC(IntPtr state)
{
var L = Lua.FromIntPtr(state);
var stream = ToStream(L, true);
if (stream is not null)
stream.Close();
return 0;
}
}