From c4d78e17ffcc747fb1390863f7161813e5db0587 Mon Sep 17 00:00:00 2001 From: Kyle Isom Date: Thu, 22 Feb 2018 11:38:27 -0800 Subject: [PATCH] misc/kforth: Initial import. --- Makefile | 13 +++ defs.h | 9 ++ doc/Makefile | 216 +++++++++++++++++++++++++++++++++++ doc/conf.py | 283 ++++++++++++++++++++++++++++++++++++++++++++++ doc/index.rst | 18 +++ doc/part-0x01.rst | 91 +++++++++++++++ doc/part-0x02.rst | 274 ++++++++++++++++++++++++++++++++++++++++++++ io.h | 24 ++++ kforth.cc | 34 ++++++ linux.h | 12 ++ linux/defs.h | 7 ++ linux/io.cc | 79 +++++++++++++ linux/io.h | 23 ++++ 13 files changed, 1083 insertions(+) create mode 100644 Makefile create mode 100644 defs.h create mode 100644 doc/Makefile create mode 100644 doc/conf.py create mode 100644 doc/index.rst create mode 100644 doc/part-0x01.rst create mode 100644 doc/part-0x02.rst create mode 100644 io.h create mode 100644 kforth.cc create mode 100644 linux.h create mode 100644 linux/defs.h create mode 100644 linux/io.cc create mode 100644 linux/io.h diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..9eb07c9 --- /dev/null +++ b/Makefile @@ -0,0 +1,13 @@ +CXXSTD := c++11 +CXXFLAGS := -std=$(CXXSTD) -Wall -Werror -g -O0 +OBJS := linux/io.o \ + kforth.o +TARGET := kforth + +all: $(TARGET) + +$(TARGET): $(OBJS) + $(CXX) $(CFLAGS) -o $@ $(OBJS) + +clean: + rm -f $(OBJS) $(TARGET) diff --git a/defs.h b/defs.h new file mode 100644 index 0000000..4197b6b --- /dev/null +++ b/defs.h @@ -0,0 +1,9 @@ +#ifndef __KF_DEFS_H__ +#define __KF_DEFS_H__ + +#ifdef __linux__ +#include "linux/defs.h" +#endif + + +#endif // __KF_DEFS_H__ \ No newline at end of file diff --git a/doc/Makefile b/doc/Makefile new file mode 100644 index 0000000..3d15563 --- /dev/null +++ b/doc/Makefile @@ -0,0 +1,216 @@ +# Makefile for Sphinx documentation +# + +# You can set these variables from the command line. +SPHINXOPTS = +SPHINXBUILD = sphinx-build +PAPER = +BUILDDIR = _build + +# User-friendly check for sphinx-build +ifeq ($(shell which $(SPHINXBUILD) >/dev/null 2>&1; echo $$?), 1) +$(error The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed, then set the SPHINXBUILD environment variable to point to the full path of the '$(SPHINXBUILD)' executable. Alternatively you can add the directory with the executable to your PATH. If you don't have Sphinx installed, grab it from http://sphinx-doc.org/) +endif + +# Internal variables. +PAPEROPT_a4 = -D latex_paper_size=a4 +PAPEROPT_letter = -D latex_paper_size=letter +ALLSPHINXOPTS = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) . +# the i18n builder cannot share the environment and doctrees with the others +I18NSPHINXOPTS = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) . + +.PHONY: help +help: + @echo "Please use \`make ' where is one of" + @echo " html to make standalone HTML files" + @echo " dirhtml to make HTML files named index.html in directories" + @echo " singlehtml to make a single large HTML file" + @echo " pickle to make pickle files" + @echo " json to make JSON files" + @echo " htmlhelp to make HTML files and a HTML help project" + @echo " qthelp to make HTML files and a qthelp project" + @echo " applehelp to make an Apple Help Book" + @echo " devhelp to make HTML files and a Devhelp project" + @echo " epub to make an epub" + @echo " latex to make LaTeX files, you can set PAPER=a4 or PAPER=letter" + @echo " latexpdf to make LaTeX files and run them through pdflatex" + @echo " latexpdfja to make LaTeX files and run them through platex/dvipdfmx" + @echo " text to make text files" + @echo " man to make manual pages" + @echo " texinfo to make Texinfo files" + @echo " info to make Texinfo files and run them through makeinfo" + @echo " gettext to make PO message catalogs" + @echo " changes to make an overview of all changed/added/deprecated items" + @echo " xml to make Docutils-native XML files" + @echo " pseudoxml to make pseudoxml-XML files for display purposes" + @echo " linkcheck to check all external links for integrity" + @echo " doctest to run all doctests embedded in the documentation (if enabled)" + @echo " coverage to run coverage check of the documentation (if enabled)" + +.PHONY: clean +clean: + rm -rf $(BUILDDIR)/* + +.PHONY: html +html: + $(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html + @echo + @echo "Build finished. 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The XML files are in $(BUILDDIR)/xml." + +.PHONY: pseudoxml +pseudoxml: + $(SPHINXBUILD) -b pseudoxml $(ALLSPHINXOPTS) $(BUILDDIR)/pseudoxml + @echo + @echo "Build finished. The pseudo-XML files are in $(BUILDDIR)/pseudoxml." diff --git a/doc/conf.py b/doc/conf.py new file mode 100644 index 0000000..39bbf81 --- /dev/null +++ b/doc/conf.py @@ -0,0 +1,283 @@ +# -*- coding: utf-8 -*- +# +# Write You a Forth documentation build configuration file, created by +# sphinx-quickstart on Thu Feb 22 08:15:32 2018. +# +# This file is execfile()d with the current directory set to its +# containing dir. +# +# Note that not all possible configuration values are present in this +# autogenerated file. +# +# All configuration values have a default; values that are commented out +# serve to show the default. + +import sys +import os + +# If extensions (or modules to document with autodoc) are in another directory, +# add these directories to sys.path here. If the directory is relative to the +# documentation root, use os.path.abspath to make it absolute, like shown here. +#sys.path.insert(0, os.path.abspath('.')) + +# -- General configuration ------------------------------------------------ + +# If your documentation needs a minimal Sphinx version, state it here. +#needs_sphinx = '1.0' + +# Add any Sphinx extension module names here, as strings. They can be +# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom +# ones. +extensions = [] + +# Add any paths that contain templates here, relative to this directory. +templates_path = ['_templates'] + +# The suffix(es) of source filenames. +# You can specify multiple suffix as a list of string: +# source_suffix = ['.rst', '.md'] +source_suffix = '.rst' + +# The encoding of source files. +#source_encoding = 'utf-8-sig' + +# The master toctree document. +master_doc = 'index' + +# General information about the project. +project = u'Write You a Forth' +copyright = u'2018, K. Isom' +author = u'K. Isom' + +# The version info for the project you're documenting, acts as replacement for +# |version| and |release|, also used in various other places throughout the +# built documents. +# +# The short X.Y version. +version = u'0.0.1' +# The full version, including alpha/beta/rc tags. +release = u'0.0.1' + +# The language for content autogenerated by Sphinx. Refer to documentation +# for a list of supported languages. +# +# This is also used if you do content translation via gettext catalogs. +# Usually you set "language" from the command line for these cases. +language = None + +# There are two options for replacing |today|: either, you set today to some +# non-false value, then it is used: +#today = '' +# Else, today_fmt is used as the format for a strftime call. +#today_fmt = '%B %d, %Y' + +# List of patterns, relative to source directory, that match files and +# directories to ignore when looking for source files. +exclude_patterns = ['_build'] + +# The reST default role (used for this markup: `text`) to use for all +# documents. +#default_role = None + +# If true, '()' will be appended to :func: etc. cross-reference text. +#add_function_parentheses = True + +# If true, the current module name will be prepended to all description +# unit titles (such as .. function::). +#add_module_names = True + +# If true, sectionauthor and moduleauthor directives will be shown in the +# output. They are ignored by default. +#show_authors = False + +# The name of the Pygments (syntax highlighting) style to use. +pygments_style = 'sphinx' + +# A list of ignored prefixes for module index sorting. +#modindex_common_prefix = [] + +# If true, keep warnings as "system message" paragraphs in the built documents. +#keep_warnings = False + +# If true, `todo` and `todoList` produce output, else they produce nothing. +todo_include_todos = False + + +# -- Options for HTML output ---------------------------------------------- + +# The theme to use for HTML and HTML Help pages. See the documentation for +# a list of builtin themes. +html_theme = 'alabaster' + +# Theme options are theme-specific and customize the look and feel of a theme +# further. For a list of options available for each theme, see the +# documentation. +#html_theme_options = {} + +# Add any paths that contain custom themes here, relative to this directory. +#html_theme_path = [] + +# The name for this set of Sphinx documents. If None, it defaults to +# " v documentation". +#html_title = None + +# A shorter title for the navigation bar. Default is the same as html_title. +#html_short_title = None + +# The name of an image file (relative to this directory) to place at the top +# of the sidebar. +#html_logo = None + +# The name of an image file (relative to this directory) to use as a favicon of +# the docs. This file should be a Windows icon file (.ico) being 16x16 or 32x32 +# pixels large. +#html_favicon = None + +# Add any paths that contain custom static files (such as style sheets) here, +# relative to this directory. They are copied after the builtin static files, +# so a file named "default.css" will overwrite the builtin "default.css". +html_static_path = ['_static'] + +# Add any extra paths that contain custom files (such as robots.txt or +# .htaccess) here, relative to this directory. These files are copied +# directly to the root of the documentation. +#html_extra_path = [] + +# If not '', a 'Last updated on:' timestamp is inserted at every page bottom, +# using the given strftime format. +#html_last_updated_fmt = '%b %d, %Y' + +# If true, SmartyPants will be used to convert quotes and dashes to +# typographically correct entities. +#html_use_smartypants = True + +# Custom sidebar templates, maps document names to template names. +#html_sidebars = {} + +# Additional templates that should be rendered to pages, maps page names to +# template names. +#html_additional_pages = {} + +# If false, no module index is generated. +#html_domain_indices = True + +# If false, no index is generated. +#html_use_index = True + +# If true, the index is split into individual pages for each letter. +#html_split_index = False + +# If true, links to the reST sources are added to the pages. +#html_show_sourcelink = True + +# If true, "Created using Sphinx" is shown in the HTML footer. Default is True. +#html_show_sphinx = True + +# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True. +#html_show_copyright = True + +# If true, an OpenSearch description file will be output, and all pages will +# contain a tag referring to it. The value of this option must be the +# base URL from which the finished HTML is served. +#html_use_opensearch = '' + +# This is the file name suffix for HTML files (e.g. ".xhtml"). +#html_file_suffix = None + +# Language to be used for generating the HTML full-text search index. +# Sphinx supports the following languages: +# 'da', 'de', 'en', 'es', 'fi', 'fr', 'hu', 'it', 'ja' +# 'nl', 'no', 'pt', 'ro', 'ru', 'sv', 'tr' +#html_search_language = 'en' + +# A dictionary with options for the search language support, empty by default. +# Now only 'ja' uses this config value +#html_search_options = {'type': 'default'} + +# The name of a javascript file (relative to the configuration directory) that +# implements a search results scorer. If empty, the default will be used. +#html_search_scorer = 'scorer.js' + +# Output file base name for HTML help builder. +htmlhelp_basename = 'WriteYouaForthdoc' + +# -- Options for LaTeX output --------------------------------------------- + +latex_elements = { +# The paper size ('letterpaper' or 'a4paper'). +#'papersize': 'letterpaper', + +# The font size ('10pt', '11pt' or '12pt'). +#'pointsize': '10pt', + +# Additional stuff for the LaTeX preamble. +#'preamble': '', + +# Latex figure (float) alignment +#'figure_align': 'htbp', +} + +# Grouping the document tree into LaTeX files. List of tuples +# (source start file, target name, title, +# author, documentclass [howto, manual, or own class]). +latex_documents = [ + (master_doc, 'WriteYouaForth.tex', u'Write You a Forth Documentation', + u'K. Isom', 'manual'), +] + +# The name of an image file (relative to this directory) to place at the top of +# the title page. +#latex_logo = None + +# For "manual" documents, if this is true, then toplevel headings are parts, +# not chapters. +#latex_use_parts = False + +# If true, show page references after internal links. +#latex_show_pagerefs = False + +# If true, show URL addresses after external links. +#latex_show_urls = False + +# Documents to append as an appendix to all manuals. +#latex_appendices = [] + +# If false, no module index is generated. +#latex_domain_indices = True + + +# -- Options for manual page output --------------------------------------- + +# One entry per manual page. List of tuples +# (source start file, name, description, authors, manual section). +man_pages = [ + (master_doc, 'writeyouaforth', u'Write You a Forth Documentation', + [author], 1) +] + +# If true, show URL addresses after external links. +#man_show_urls = False + + +# -- Options for Texinfo output ------------------------------------------- + +# Grouping the document tree into Texinfo files. List of tuples +# (source start file, target name, title, author, +# dir menu entry, description, category) +texinfo_documents = [ + (master_doc, 'WriteYouaForth', u'Write You a Forth Documentation', + author, 'WriteYouaForth', 'One line description of project.', + 'Miscellaneous'), +] + +# Documents to append as an appendix to all manuals. +#texinfo_appendices = [] + +# If false, no module index is generated. +#texinfo_domain_indices = True + +# How to display URL addresses: 'footnote', 'no', or 'inline'. +#texinfo_show_urls = 'footnote' + +# If true, do not generate a @detailmenu in the "Top" node's menu. +#texinfo_no_detailmenu = False diff --git a/doc/index.rst b/doc/index.rst new file mode 100644 index 0000000..bee3448 --- /dev/null +++ b/doc/index.rst @@ -0,0 +1,18 @@ +Write You a Forth +================= + +Contents: + +.. toctree:: + :maxdepth: 2 + + part-0x01 + part-0x02 + +Indices and tables +================== + +* :ref:`genindex` +* :ref:`modindex` +* :ref:`search` + diff --git a/doc/part-0x01.rst b/doc/part-0x01.rst new file mode 100644 index 0000000..c609537 --- /dev/null +++ b/doc/part-0x01.rst @@ -0,0 +1,91 @@ +Write You a Forth, 0x01 +----------------------- + +:date: 2018-02-21 23:17 +:tags: wyaf, forth + +Following on from the `last post`_ I've decided to frame this as a Write You an +X-type series where I'll write up my thinking and planning as I go. + +.. _last post: https://dl.kyleisom.net/posts/2018/02/21/2018-02-21-revisiting-forth/ + +The basics +^^^^^^^^^^ + +Let's start with the basics: what are the characteristics of a Forth? First, +it's a stack-based language, so it'll need a stack. Actually, it'll need at +least two stacks --- the data stack and the return stack (where return addresses +are normally stored). Modern Forths also have a floating point stack. + +Forth calls functions *words*, and the FORTH-83 standard defines a set of +required words for an implementation. Note that there is an ANS Forth, but I'll +target FORTH-83 first for simplicity. The `required words`_ are: + +.. _required words: http://forth.sourceforge.net/standard/fst83/fst83-12.htm) + +**Nucleus layer**:: + + ! * */ */MOD + +! - / /MOD 0< 0= 0> 1+ 1- 2+ + 2- 2/ < = > >R ?DUP @ ABS AND C! C@ CMOVE + CMOVE> COUNT D+ D< DEPTH DNEGATE DROP DUP EXECUTE + EXIT FILL I J MAX MIN MOD NEGATE NOT OR OVER PICK + R> R@ ROLL ROT SWAP U< UM* UM/MOD XOR + +**Device layer**:: + + BLOCK BUFFER CR EMIT EXPECT FLUSH KEY SAVE-BUFFERS + SPACE SPACES TYPE UPDATE + +**Interpreter layer**:: + + # #> #S #TIB ' ( -TRAILING . .( <# >BODY >IN + ABORT BASE BLK CONVERT DECIMAL DEFINITIONS FIND + FORGET FORTH FORTH-83 HERE HOLD LOAD PAD QUIT SIGN + SPAN TIB U. WORD + +**Compiler layer**:: + + +LOOP , ." : ; ABORT" ALLOT BEGIN COMPILE CONSTANT + CREATE DO DOES> ELSE IF IMMEDIATE LEAVE LITERAL LOOP + REPEAT STATE THEN UNTIL VARIABLE VOCABULARY WHILE + ['] [COMPILE] ] + +In a lot of cases, Forth is also the operating system for the device. This +won't be a target at first, but something to keep in mind as I progress. + +Eventually, I'd like to build a zero-allocation Forth that can run on an +STM-32 or an MSP430, but the first goal is going to get a minimal Forth +working. I'll define the stages as + +Stage 1 +~~~~~~~ + +1. Runs on Linux (that's what my Pixelbook runs, more or less). +2. Implements the nucleus layer. +3. Has a REPL that works in a terminal. +4. Explicit non-goal: performance. I'll build a working minimal Forth to get a + baseline experience. + +Stage 2 +~~~~~~~ + +1. Implement the compiler and interpreter layers. + +Stage 3 +~~~~~~~~ + +1. Define a block layer interface. +2. Implement a Linux block layer interface. + +Stage 4 +~~~~~~~~ + +1. Build a memory management system. +2. Replace all managed memory with the homebrew memory management system. +3. Switch to a JPL rule #3 (no heap allocation) implementation. + +Next steps +^^^^^^^^^^ + +I don't really know what I'm doing, so in the next section, I'll build out the +basic framework and set up the build. \ No newline at end of file diff --git a/doc/part-0x02.rst b/doc/part-0x02.rst new file mode 100644 index 0000000..bb1259b --- /dev/null +++ b/doc/part-0x02.rst @@ -0,0 +1,274 @@ +Write You a Forth, 0x02 +----------------------- + +:date: 2018-02-22 10:48 +:tags: wyaf, forth + +The basic framework will consist of two main parts: + +1. A modular I/O subsystem: on Linux, it makes sense to use the operating + system's terminal I/O features. On the MSP430, there won't be the luxury + of any operating system and I'll have to build out the I/O facilities. The + I/O interface will be defined in ``io.h``; the build system will eventually + have to decide which interface implementation to bring in. + +2. A toplevel function (the C++ ``main`` function, for example) that will + handle starting up the Forth system and bring us into an interpreter. We'll + put this in ``kforth.cc``. + +The project will also need a build system. For simplicity, I'll at least start +with a basic Makefile:: + + # Makefile + CXXSTD := c++11 + CXXFLAGS := -std=$(CXXSTD) -Werror -Wall -g -O0 + OBJS := linux/io.o \ + kforth.o + TARGET := kforth + + all: $(TARGET) + + $(TARGET): $(OBJS) + $(CXX) $(CFLAGS) -o $@ $(OBJS) + + clean: + rm -f $(OBJS) $(TARGET) + +A simple frontend +^^^^^^^^^^^^^^^^^ + +Starting out with the most basic front end; we'll first want to include our I/O +interface:: + + #include "io.h" + +If kforth is running on Linux, and it will be for the first stage, the +frontend should pull in Linux specific pieces. ``linux.h`` is the place +to set up the Linux-specific pieces:: + + #ifdef __linux__ + #include "linux.h" + #endif // __linux__ + +The interpreter function takes an I/O interface instance, and reads lines in +an infinite loop, printing "ok" after each line is read. I'll go over the +methods called on the ``interface`` instance when I get to the I/O subsystem. +Printing the line buffer right now helps to verify that the I/O subsystem is +working correctly:: + + static char ok[] = "ok.\n"; + + static void + interpreter(IO &interface) + { + static size_t buflen = 0; + static char linebuf[81]; + + while (true) { + buflen = interface.rdbuf(linebuf, 80, true, '\n'); + interface.wrln(linebuf, buflen); + interface.wrbuf(ok, 4); + } + } + +The main function, for right now, can just instantiate a new I/O interface and +then call the interpreter:: + + static char banner[] = "kforth interpreter\n"; + const size_t bannerlen = 19; + + int + main(void) + { + #ifdef __linux__ + Console interface; + #endif + interface.wrbuf(banner, bannerlen); + interpreter(interface); + return 0; + } + +That gives a good interactive test framework that I can use to start playing +with the system. I'm trying to avoid bringing in ``iostream`` directly in order +to force writing and building useful tooling built around the I/O interface. +This is, after all, the Forth ideal: start with a core system, then build your +world on top of that. + +The I/O interface +^^^^^^^^^^^^^^^^^ + +In the truest of C++ fashions, the I/O interface is defined with the ``IO`` +abstract base class:: + + #ifndef __KF_IO_H__ + #define __KF_IO_H__ + + #include "defs.h" + + class IO { + public: + // Virtual destructor is required in all ABCs. + virtual ~IO() {}; + +The two building block methods are the lowest-level. My original plan was to +include these in the interface, but there's one snag with that: line endings. +But, we'll get to that. +:: + + // Building block methods. + virtual char rdch(void) = 0; + virtual void wrch(char c) = 0; + +I could have just made the buffer I/O methods functions inside the ``io.h`` +header, but it seems easy to just include them here. I may move them outside +the class later, though. +:: + + // Buffer I/O. + virtual size_t rdbuf(char *buf, size_t len, bool stopat, char stopch) = 0; + virtual void wrbuf(char *buf, size_t len) = 0; + +Line I/O presents some challenges. On a serial console, it's the sequence 0x0d +0x0a; on the Linux terminal, it's 0x0a. Therefore, reading a line is +platform-dependent, and I can't just make this a generic function unless I want +to handle all the cases. And, *surprise surprise*, right now I don't. +:: + + // Line I/O + virtual bool rdln(char *buf, size_t len, size_t *readlen) = 0; + virtual void wrln(char *buf, size_t len) = 0; + }; + + #endif // __KF_IO_H__ + +The Linux implementation is the ``Console`` (as seen in ``main``). The header +file isn't interesting; it's basically a copy of ``io.h`` in ``linux/io.h``. +:: + + #include + #include "../io.h" + #include "io.h" + +The building blocks flush I/O. ``getchar`` is used instead of ``cin`` because +the latter skips whitespace. Later, flushing may be removed but it's not a +performance concern yet. +:: + + char + Console::rdch() + { + std::cout.flush(); + return getchar(); + } + + + void + Console::wrch(char c) + { + std::cout.flush(); + std::cout << c; + } + +The buffer read and write functions are straightforward, and are just built on +top of the character read and write methods. +:: + + size_t + Console::rdbuf(char *buf, size_t len, bool stopat, char stopch) + { + size_t n = 0; + char ch; + + while (n < len) { + ch = this->rdch(); + + if (stopat && stopch == ch) { + break; + } + + buf[n++] = ch; + } + + return n; + } + + + void + Console::wrbuf(char *buf, size_t len) + { + for (size_t n = 0; n < len; n++) { + this->wrch(buf[n]); + } + } + +Line reading doesn't reuse the buffer I/O functions, because the latter +doesn't indicate whether the buffer ran out or the line has ended. I could add +length checks and whatnot, but this is straightforward and gives me something +to work with now. Again, the mantra is dumb and works rather than clever. For +now. +:: + + bool + Console::rdln(char *buf, size_t len, size_t *readlen) { + size_t n = 0; + char ch; + bool line = false; + + while (n < len) { + ch = this->rdch(); + + if (ch == '\n') { + line = true; + break; + } + + buf[n++] = ch; + } + + if (nullptr != readlen) { + *readlen = n; + } + return line; + } + +Line writing, however, can absolutely reuse the buffer and character I/O +methods. +:: + + void + Console::wrln(char *buf, size_t len) + { + this->wrbuf(buf, len); + this->wrch(0x0a); + } + +``defs.h`` +^^^^^^^^^^ + +The common definition file ``defs.h`` is just a front for the actual platform +definitions:: + + #ifndef __KF_DEFS_H__ + #define __KF_DEFS_H__ + + #ifdef __linux__ + #include "linux/defs.h" + #endif + + + #endif // __KF_DEFS_H__ + +The Linux definitions in ``linux/defs.h`` just bring in the standard +definitions from the standard library:: + + #ifndef __KF_LINUX_DEFS_H__ + #define __KF_LINUX_DEFS_H__ + + #include + + #endif + +Next steps +^^^^^^^^^^ + +I guess the next thing to do will be to start parsing. \ No newline at end of file diff --git a/io.h b/io.h new file mode 100644 index 0000000..fa25c5c --- /dev/null +++ b/io.h @@ -0,0 +1,24 @@ +#ifndef __KF_IO_H__ +#define __KF_IO_H__ + +#include "defs.h" + +class IO { +public: + // Virtual destructor is required in all ABCs. + virtual ~IO() {}; + + // Building block methods. + virtual char rdch(void) = 0; + virtual void wrch(char c) = 0; + + // Buffer I/O. + virtual size_t rdbuf(char *buf, size_t len, bool stopat, char stopch) = 0; + virtual void wrbuf(char *buf, size_t len) = 0; + + // Line I/O + virtual bool rdln(char *buf, size_t len, size_t *readlen) = 0; + virtual void wrln(char *buf, size_t len) = 0; +}; + +#endif // __KF_IO_H__ \ No newline at end of file diff --git a/kforth.cc b/kforth.cc new file mode 100644 index 0000000..218b599 --- /dev/null +++ b/kforth.cc @@ -0,0 +1,34 @@ +#include "io.h" + +#ifdef __linux__ +#include "linux.h" +#endif // __linux__ + +static char ok[] = "ok.\n"; + +static void +interpreter(IO &interface) +{ + static size_t buflen = 0; + static char linebuf[81]; + + while (true) { + buflen = interface.rdbuf(linebuf, 80, true, '\n'); + interface.wrln(linebuf, buflen); + interface.wrbuf(ok, 4); + } +} + +static char banner[] = "kforth interpreter\n"; +const size_t bannerlen = 19; + +int +main(void) +{ +#ifdef __linux__ + Console interface; +#endif + interface.wrbuf(banner, bannerlen); + interpreter(interface); + return 0; +} \ No newline at end of file diff --git a/linux.h b/linux.h new file mode 100644 index 0000000..fe69a0e --- /dev/null +++ b/linux.h @@ -0,0 +1,12 @@ +#ifndef __KF_LINUX_H__ +#define __KF_LINUX_H__ + +#include + +// build support for linux +#include "linux/io.h" + +constexpr uint8_t STACK_SIZE = 128; + + +#endif // __KF_LINUX_H__ diff --git a/linux/defs.h b/linux/defs.h new file mode 100644 index 0000000..78228d9 --- /dev/null +++ b/linux/defs.h @@ -0,0 +1,7 @@ +#ifndef __KF_LINUX_DEFS_H__ +#define __KF_LINUX_DEFS_H__ + +#include + + +#endif \ No newline at end of file diff --git a/linux/io.cc b/linux/io.cc new file mode 100644 index 0000000..aeef8bb --- /dev/null +++ b/linux/io.cc @@ -0,0 +1,79 @@ +#include +#include "../io.h" +#include "io.h" + +char +Console::rdch() +{ + std::cout.flush(); + return getchar(); +} + + +void +Console::wrch(char c) +{ + std::cout << c; +} + + +size_t +Console::rdbuf(char *buf, size_t len, bool stopat, char stopch) +{ + size_t n = 0; + char ch; + + while (n < len) { + ch = this->rdch(); + + if (stopat && stopch == ch) { + break; + } + + buf[n++] = ch; + } + + return n; +} + + +void +Console::wrbuf(char *buf, size_t len) +{ + for (size_t n = 0; n < len; n++) { + this->wrch(buf[n]); + } +} + + +// Line I/O +bool +Console::rdln(char *buf, size_t len, size_t *readlen) { + size_t n = 0; + char ch; + bool line = false; + + while (n < len) { + ch = this->rdch(); + + if (ch == '\n') { + line = true; + break; + } + + buf[n++] = ch; + } + + if (nullptr != readlen) { + *readlen = n; + } + return line; +} + + +void +Console::wrln(char *buf, size_t len) +{ + this->wrbuf(buf, len); + this->wrch(0x0a); +} \ No newline at end of file diff --git a/linux/io.h b/linux/io.h new file mode 100644 index 0000000..a64e7e4 --- /dev/null +++ b/linux/io.h @@ -0,0 +1,23 @@ +#ifndef __KF_IO_LINUX_H__ +#define __KF_IO_LINUX_H__ + +#include "io.h" +#include "defs.h" + +class Console : public IO { +public: + ~Console() {}; + char rdch(void); + void wrch(char c); + + // Buffer I/O. + size_t rdbuf(char *buf, size_t len, bool stopat, char stopch); + void wrbuf(char *buf, size_t len); + + // Line I/O + bool rdln(char *buf, size_t len, size_t *readlen); + void wrln(char *buf, size_t len); +private: +}; + +#endif // __KF_IO_LINUX_H__