miniscm: add ports

This commit is contained in:
Peter McGoron 2024-08-22 22:43:49 -04:00
parent 93cfe0d94a
commit 9d08c1f59e
3 changed files with 189 additions and 15 deletions

View File

@ -52,6 +52,8 @@
(define (tail stream) (force (cdr stream)))
(define (eof-object? x) (eq? x #f))
;;;;; following part is written by a.k
;;;; atom?

View File

@ -25,11 +25,17 @@
*--
*/
/* TODO: Add basic port operations.
/* This version of MiniScheme has been modified to bootstrap UNSLISP.
*
* UNSLISP only needs one input port and one output port (besides stdin
* and stdout). The easiest thing to do is to make ports integers that
* reference a global list of FILE*.
* Additions:
* * Proper support for disabling quasiquote
* * Chars
* * Proper support for changing init file by preprocessor define
* * Ports
*
* Ports and chars only support the minimum necessary to run UNSLISP.
* The eof-object is #f. (Defining an entire type for EOF seems like
* a kludge. An EOF test function would be a better design.)
*/
/*
@ -112,7 +118,8 @@
#define banner "Hello, This is Mini-Scheme Interpreter Version 0.85k4-a for UNSLISP.\n"
#define banner "UNSLISP MiniScheme 0.85k4-a fork. Must be run from the \n\
UNSLISP repository root directory.\n"
#include <stdio.h>
@ -235,6 +242,7 @@ typedef struct cell *pointer;
#endif
#define T_PROMISE 512 /* 0000001000000000 */
#define T_CHAR 1024 /* 0000010000000000 */
#define T_PORT 2048 /* 0000100000000000 */
#define T_ATOM 16384 /* 0100000000000000 */ /* only for gc */
#define CLRATOM 49151 /* 1011111111111111 */ /* only for gc */
#define MARK 32768 /* 1000000000000000 */
@ -260,6 +268,8 @@ typedef struct cell *pointer;
#define hasprop(p) (type(p)&T_SYMBOL)
#define symprop(p) cdr(p)
#define isport(p) (type(p)&T_PORT)
#define issyntax(p) (type(p)&T_SYNTAX)
#define isproc(p) (type(p)&T_PROC)
#define syntaxname(p) strvalue(car(p))
@ -335,6 +345,11 @@ long fcells = 0; /* # of free cells */
FILE *infp; /* input file */
FILE *outfp; /* output file */
#ifndef PORTMAX
# define PORTMAX 8
#endif
FILE *ports[PORTMAX]; /* Ports */
#ifdef USE_SETJMP
jmp_buf error_jmp;
@ -550,22 +565,27 @@ char *q;
return (mk_number(atol(q)));
}
pointer mk_char_c(c)
char c;
{
register pointer x = get_cell(NIL, NIL);
type(x) = (T_CHAR | T_ATOM);
ivalue(x) = c;
return x;
}
/* make char */
pointer mk_char(name)
char *name;
{
register pointer x = get_cell(NIL, NIL);
type(x) = (T_CHAR | T_ATOM);
if (stricmp(name, "space") == 0) {
ivalue(x) = ' ';
name[0] = ' ';
} else if (stricmp(name, "newline") == 0) {
ivalue(x) = '\n';
} else {
ivalue(x) = *name;
name[0] = '\n';
}
return x;
return mk_char_c(name[0]);
}
/* make constant */
@ -912,6 +932,9 @@ int f;
p = strbuff;
sprintf(p, "#\\%c", ivalue(l));
}
} else if (isport(l)) {
p = strbuff;
sprintf(p, "#<PORT %ld>", ivalue(l));
}
if (f < 0)
return strlen(p);
@ -1008,6 +1031,11 @@ register pointer a, b;
return (ivalue(a) == ivalue(b));
else
return (0);
} else if (isport(a)) {
if (isport(b))
return (ivalue(a) == ivalue(b));
else
return (0);
} else
return (a == b);
}
@ -1177,6 +1205,14 @@ register pointer a, b;
#define OP_MACROP 103
#define OP_CHAR 104
#define OP_OPENIN 105
#define OP_CLOSEIN 106
#define OP_READIN 107
#define OP_OPENOUT 108
#define OP_CLOSEOUT 109
#define OP_WRITEOUT 110
static FILE *tmpfp;
static int tok;
static int print_flag;
@ -2182,7 +2218,110 @@ register short op;
return T; /* NOTREACHED */
}
#define CANNOT_OPEN_FILE -1
#define TOO_MANY_PORTS -2
int try_to_open(name, mode)
const char *name;
const char *mode;
{
register int x;
for (x = 0; x < PORTMAX; x++) {
if (ports[x] == NULL) {
ports[x] = fopen(name, mode);
if (!ports[x])
return CANNOT_OPEN_FILE;
return x;
}
}
return TOO_MANY_PORTS;
}
pointer mk_port(port)
int port;
{
register pointer x = get_cell(NIL, NIL);
type(x) = (T_PORT | T_ATOM);
ivalue(x) = port;
return x;
}
pointer opexe_7(op)
register short op;
{
pointer x;
int port;
switch (op) {
case OP_OPENIN: case OP_OPENOUT:
if (!isstring(car(args))) {
Error_0("open-input/output-file -- argument is not string");
}
port = try_to_open(strvalue(car(args)), op == OP_OPENIN ? "rb" : "wb");
switch (port) {
case CANNOT_OPEN_FILE:
Error_1("open-input/output-file -- cannot open file", car(args));
case TOO_MANY_PORTS:
Error_0("open-input/output-file -- too many ports open");
default:
x = mk_port(port);
s_return(x);
}
case OP_CLOSEIN: case OP_CLOSEOUT:
if (!isport(car(args))) {
Error_0("close-input/output-file -- argument is not port");
}
port = ivalue(car(args));
if (port < 0 || port >= PORTMAX) {
Error_0("close-input/output-file -- corrupted port value");
}
fclose(ports[port]);
ports[port] = NULL;
s_return(T);
case OP_READIN:
if (!isport(car(args))) {
Error_0("read-char -- argument is not port");
}
port = ivalue(car(args));
if (port < 0 || port >= PORTMAX) {
Error_0("read-char -- corrupted port value");
}
port = getc(ports[port]);
if (port == EOF) {
x = F;
} else {
x = mk_char_c((char)port);
}
s_return(x);
case OP_WRITEOUT:
if (!isport(car(args))) {
Error_0("write-char -- 1st argument is not port");
}
if (!ischar(cadr(args))) {
Error_0("write-char -- 2nd argument is not char");
}
port = ivalue(car(args));
if (port < 0 || port >= PORTMAX) {
Error_0("read-char -- corrupted port value");
}
putc((char)ivalue(cadr(args)), ports[port]);
s_return(T);
default:
sprintf(strbuff, "%d is illegal operator", operator);
Error_0(strbuff);
}
return T;
}
pointer (*dispatch_table[])() = {
@ -2301,7 +2440,14 @@ pointer (*dispatch_table[])() = {
* operator when macros are disabled. */
opexe_6, /* OP_MACROP, */
opexe_3 /* OP_CHAR */
opexe_3, /* OP_CHAR */
opexe_7, /* OP_OPENIN */
opexe_7, /* OP_CLOSEIN */
opexe_7, /* OP_READIN */
opexe_7, /* OP_OPENOUT */
opexe_7, /* OP_CLOSEOUT */
opexe_7 /* OP_WRITEOUT */
};
@ -2450,6 +2596,14 @@ init_procs()
#endif
mk_proc(OP_QUIT, "quit");
mk_proc(OP_CHAR, "char?");
mk_proc(OP_OPENIN, "open-input-file");
mk_proc(OP_CLOSEIN, "close-input-port");
mk_proc(OP_READIN, "read-char");
mk_proc(OP_OPENOUT, "open-output-file");
mk_proc(OP_CLOSEOUT, "close-output-port");
mk_proc(OP_WRITEOUT, "write-char");
}

18
miniscm/test.scm Normal file
View File

@ -0,0 +1,18 @@
(define copy
(lambda (from to)
(let ((from-file (open-input-file from))
(to-file (open-output-file to)))
(letrec
((loop
(lambda ()
(let ((c (read-char from-file)))
(if (eof-object? c)
#f
(begin
(write-char to-file c)
(loop)))))))
(loop))
(close-input-port from-file)
(close-output-port to-file))))
(copy "miniscm/miniscm.c" "/tmp/miniscm-copy.c")