Merge pull request #455 from Wilma456/fileread

Add read() to Filehandle

src/main/java/dan200/computercraft/core/apis/handles/EncodedInputHandle.java

@@ -6,6 +6,8 @@ import dan200.computercraft.api.lua.LuaException;
 import javax.annotation.Nonnull;
 import java.io.*;
 
+import static dan200.computercraft.core.apis.ArgumentHelper.*;
+
 public class EncodedInputHandle extends HandleGeneric
 {
     private final BufferedReader m_reader;
@@ -49,6 +51,7 @@ public class EncodedInputHandle extends HandleGeneric
             "readLine",
             "readAll",
             "close",
+            "read",
         };
     }
 
@@ -102,6 +105,26 @@ public class EncodedInputHandle extends HandleGeneric
                 // close
                 close();
                 return null;
+            case 3:
+                // read
+                checkOpen();
+                try
+                {
+                    int count = optInt( args, 0, 1 );
+                    if( count <= 0 || count >= 1024 * 16 )
+                    {
+                        throw new LuaException( "Count out of range" );
+                    }
+                    char[] bytes = new char[ count ];
+                    count = m_reader.read( bytes );
+                    if( count < 0 ) return null;
+                    String str = new String( bytes, 0, count );
+                    return new Object[] { str };
+                }
+                catch( IOException e )
+                {
+                    return null;
+                }
             default:
                 return null;
         }

src/main/resources/assets/computercraft/lua/rom/apis/io.lua

@@ -94,6 +94,8 @@ function open( _sPath, _sMode )
 					return file.readLine()
 				elseif sFormat == "*a" then
 					return file.readAll()
+                elseif _G.type( sFormat ) == "number" then
+                    return file.read( sFormat )
 				else
 					error( "Unsupported format", 2 )
 				end

src/main/resources/assets/computercraft/lua/rom/help/fs.txt

@@ -22,6 +22,7 @@ Functions on files opened with mode "r":
 readLine()
 readAll()
 close()
+read( number )
 
 Functions on files opened with mode "w" or "a":
 write( string )
@@ -36,4 +37,4 @@ close()
 Functions on files opened with mode "wb" or "ab":
 write( byte )
 flush()
-close()
+close()