Library interface

author	Richard Brooksby
copyright	See Copyright and License.
date	1996-09-03
index terms	pair: library interface; design
revision	//info.ravenbrook.com/project/mps/master/design/lib.txt#9
status	incomplete design
tag	design.mps.lib

Introduction

.intro: This document is the design of the MPS Library Interface, a part of the plinth.

.readership: Any MPS developer. Any clients that are prepared to read this in order to get documentation.

Goals

.goal: The goals of the MPS library interface are:

.goal.host: To control the dependency of the MPS on the hosted ISO C library so that the core MPS remains freestanding (see design.mps.exec-env).

.goal.free: To allow the core MPS convenient access to ISO C functionality that is provided on freestanding platforms (see design.mps.exec-env).

Description

Overview

.overview.access: The core MPS needs to access functionality that could be provided by an ISO C hosted environment.

.overview.hosted: The core MPS must not make direct use of any facilities in the hosted environment (design.mps.exec-env). However, it is sensible to make use of them when the MPS is deployed in a hosted environment.

.overview.hosted.indirect: The core MPS does not make any direct use of hosted ISO C library facilities. Instead, it indirects through the MPS Library Interface, impl.h.mpslib.

.overview.provision.client: In a freestanding environment the client is expected to provide functions meeting this interface to the MPS.

.overview.provision.hosted: In a hosted environment, impl.c.mpsliban may be used. It just maps impl.h.mpslib directly onto the ISO C library equivalents.

Implementation

.impl: The MPS Library Interface comprises a header file impl.h.mpslib and some documentation.

.impl.decl: The header file defines the interface to definitions which parallel those parts of the non-freestanding ISO headers which are used by the MPS.

.impl.include: The header file also includes the freestanding header <stddef.h>.

Document History

1996-09-03 RB Incomplete design.
2002-06-07 RB Converted from MMInfo database design document.
2013-05-23 GDR Converted to reStructuredText.

Copyright and License

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

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