add io_stream:seek

res/modules/internal/stream_providers/file.lua

@@ -3,6 +3,7 @@ local io_stream = require "core:io_stream"
 local lib = {
     read = file.__read_descriptor,
     write = file.__write_descriptor,
+    seek = file.__seek_descriptor,
     flush = file.__flush_descriptor,
     is_alive = file.__has_descriptor,
     close = file.__close_descriptor

res/modules/internal/stream_providers/named_pipe_unix.lua

@@ -58,6 +58,10 @@ function lib.write(fd, bytearray)
     end
 end
 
+function lib.seek(fd, mode, offset)
+    error("cannot seek the named pipe")
+end
+
 function lib.flush(fd)
     -- no flush on unix
 end

res/modules/internal/stream_providers/named_pipe_windows.lua

@@ -62,7 +62,7 @@ function lib.read(handle, len)
 
     if not has_data then
         return out
-    elseif hasData == -1 then
+    elseif has_data == -1 then
         error("failed to read from named pipe: "..tostring(C.GetLastError()))
     end
 
@@ -84,8 +84,8 @@ end
 
 function lib.write(handle, bytearray)
     local len = #bytearray
-    
     local buffer = FFI.new("uint8_t[?]", len)
+
     for i = 1, len do
         buffer[i-1] = bytearray[i]
     end
@@ -97,6 +97,10 @@ function lib.write(handle, bytearray)
     end
 end
 
+function lib.seek(handle, mode, offset)
+    error("cannot seek the named pipe")
+end
+
 function lib.flush(handle)
     C.FlushFileBuffers(handle)
 end

res/modules/io_stream.lua

@@ -369,6 +369,10 @@ function io_stream:write(arg, ...)
     end
 end
 
+function io_stream:seek(mode, offset)
+    self.ioLib.seek(self.descriptor, mode, offset)
+end
+
 function io_stream:is_alive()
     return self.ioLib.is_alive(self.descriptor)
 end