ref: 7db38904537603dabe960f32fa505e27db89e27b
parent: d81447526cde6fa98dfa792a65f71acb78ef1398
author: Peter Mikkelsen <peter@pmikkelsen.com>
date: Sat Jul 3 14:58:07 EDT 2021
Start adding support for read_term and write_term
--- a/builtins.c
+++ b/builtins.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
@@ -41,6 +42,8 @@
BuiltinProto(builtincurrentoutput);
BuiltinProto(builtinsetinput);
BuiltinProto(builtinsetoutput);
+BuiltinProto(builtinreadterm);
+BuiltinProto(builtinwriteterm);
int compareterms(Term *, Term *);
@@ -116,6 +119,10 @@
return builtinsetinput;
if(Match(L"set_output", 1))
return builtinsetoutput;
+ if(Match(L"read_term", 3))
+ return builtinreadterm;
+ if(Match(L"write_term", 3))
+ return builtinwriteterm;
return nil;
}
@@ -536,7 +543,7 @@
Term *ball = goal->children;
- print("Throwing: %S\n", prettyprint(ball));+ print("Throwing: %S\n", prettyprint(ball, 0, 0, 0));Goal *g;
for(g = *goals; g != nil; g = g->next){if(g->catcher == nil)
@@ -545,7 +552,7 @@
if(unify(g->catcher, ball, bindings)){ if(g->goal == nil){/* As soon as we have print facilities as builtins, we can avoid this by having the protector frame have a unhandled exception handler*/
- print("Unhandled exception: %S\n", prettyprint(ball));+ print("Unhandled exception: %S\n", prettyprint(ball, 0, 0, 0)); exits("exception");return 0;
}else{@@ -727,7 +734,6 @@
builtinsetoutput(Term *database, Term *goal, Goal **goals, Choicepoint **choicestack, Binding **bindings)
{USED(database);
- USED(goal);
USED(goals);
USED(choicestack);
USED(bindings);
@@ -747,4 +753,66 @@
setcurrentoutputstream(stream);
return 1;
-}
\ No newline at end of file
+}
+
+int
+builtinreadterm(Term *database, Term *goal, Goal **goals, Choicepoint **choicestack, Binding **bindings)
+{+ USED(database);
+ USED(goals);
+ USED(choicestack);
+ USED(bindings);
+
+ Term *stream = goal->children;
+ Term *term = stream->next;
+ Term *options = term->next;
+
+ if(stream->tag == VariableTerm)
+ Throw(instantiationerror());
+ if(options->tag != AtomTerm || runestrcmp(options->text, L"[]") != 0)
+ Throw(typeerror(L"empty_list", options));
+ if((stream->tag != NumberTerm || stream->numbertype != NumberInt) && stream->tag != AtomTerm)
+ Throw(domainerror(L"stream_or_alias", stream));
+ if(!isopenstream(stream))
+ Throw(existenceerror(L"stream", stream));
+ if(isoutputstream(stream))
+ Throw(permissionerror(L"input", L"stream", stream));
+ if(isbinarystream(stream))
+ Throw(permissionerror(L"input", L"binary_stream", stream));
+
+ Term *realterm;
+ int error = readterm(stream, options, &realterm);
+ if(error)
+ Throw(realterm);
+
+ return unify(term, realterm, bindings);
+}
+
+int
+builtinwriteterm(Term *database, Term *goal, Goal **goals, Choicepoint **choicestack, Binding **bindings)
+{+ USED(database);
+ USED(goals);
+ USED(choicestack);
+ USED(bindings);
+
+ Term *stream = goal->children;
+ Term *term = stream->next;
+ Term *options = term->next;
+
+ if(stream->tag == VariableTerm)
+ Throw(instantiationerror());
+ if(options->tag != AtomTerm || runestrcmp(options->text, L"[]") != 0)
+ Throw(typeerror(L"empty_list", options));
+ if((stream->tag != NumberTerm || stream->numbertype != NumberInt) && stream->tag != AtomTerm)
+ Throw(domainerror(L"stream_or_alias", stream));
+ if(!isopenstream(stream))
+ Throw(existenceerror(L"stream", stream));
+ if(isinputstream(stream))
+ Throw(permissionerror(L"output", L"stream", stream));
+ if(isbinarystream(stream))
+ Throw(permissionerror(L"output", L"binary_stream", stream));
+ writeterm(stream, options, term);
+ return 1;
+}
+
--- a/error.c
+++ b/error.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
--- a/eval.c
+++ b/eval.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
@@ -57,7 +58,7 @@
}
if(debug)
- print("Working goal: %S\n", prettyprint(goal));+ print("Working goal: %S\n", prettyprint(goal, 0, 0, 0));Binding *bindings = nil;
Term *clause = nil;
@@ -226,6 +227,7 @@
switch(a->tag){case AtomTerm:
+ return runestrcmp(a->text, b->text) == 0;
case VariableTerm:
return (runestrcmp(a->text, b->text) == 0 && a->clausenr == b->clausenr);
case NumberTerm:
--- a/flags.c
+++ b/flags.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
--- a/fns.h
+++ b/fns.h
@@ -1,8 +1,8 @@
/* parser.c */
-Term *parse(int, int);
+Term *parse(int, Biobuf *, int);
/* prettyprint.c */
-Rune *prettyprint(Term *);
+Rune *prettyprint(Term *, int, int, int);
/* misc.c */
Term *copyterm(Term *, uvlong *);
@@ -51,4 +51,8 @@
void setcurrentoutputstream(Term *);
int isopenstream(Term *);
int isinputstream(Term *);
-int isoutputstream(Term *);
\ No newline at end of file
+int isoutputstream(Term *);
+int istextstream(Term *);
+int isbinarystream(Term *);
+int readterm(Term *, Term *, Term **);
+void writeterm(Term *, Term *, Term *);
\ No newline at end of file
--- a/main.c
+++ b/main.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
@@ -34,7 +35,7 @@
exits("open");}
- Term *database = parse(fd, 0);
+ Term *database = parse(fd, nil, 0);
close(fd);
if(parsetestfile){@@ -41,7 +42,7 @@
int fd = open(parsetestfile, OREAD);
if(fd < 0)
exits("open");- Term *clauses = parse(fd, 0);
+ Term *clauses = parse(fd, nil, 0);
database = appendterm(database, clauses);
Term *goal;
--- a/misc.c
+++ b/misc.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
--- a/parser.c
+++ b/parser.c
@@ -79,14 +79,18 @@
Term *prologtext(int);
Term *
-parse(int fd, int querymode)
+parse(int fd, Biobuf *bio, int querymode)
{- fd = dup(fd, -1);
- parsein = Bfdopen(fd, OREAD);
- if(parsein == nil){- print("Could not open file\n");- return nil;
- }
+ if(bio == nil){+ fd = dup(fd, -1);
+ parsein = Bfdopen(fd, OREAD);
+ if(parsein == nil){+ print("Could not open file\n");+ return nil;
+ }
+ }else
+ parsein = bio;
+
initgoals = nil;
initoperators();
nexttoken();
@@ -96,7 +100,9 @@
uvlong id = 1;
result = copyterm(result, &id);
}
- Bterm(parsein);
+ if(!bio)
+ Bterm(parsein);
+
return result;
}
@@ -118,7 +124,7 @@
if(t->tag == CompoundTerm && runestrcmp(t->text, L":-") == 0 && t->arity == 1){Term *body = t->children;
- print("Got directive: %S\n", prettyprint(body));+ print("Got directive: %S\n", prettyprint(body, 0, 0, 0)); if(body->tag == CompoundTerm && body->arity == 1 && runestrcmp(body->text, L"initialization") == 0){Term *tmp = initgoals;
initgoals = body->children;
@@ -296,7 +302,7 @@
if(index == -1){ print("Can't parse, list of length %d contains no operators: ", length);for(i = 0; i < length; i++)
- print("%S(%d) ", prettyprint(terms[i]), infos[i].level);+ print("%S(%d) ", prettyprint(terms[i], 0, 0, 0), infos[i].level); print("\n"); syntaxerror_parser("parseoperators");}
@@ -337,7 +343,7 @@
terms[i] = terms[i+1];
}
}else{- print("Parse error when parsing operator %S (prefix=%d, postfix=%d, infix=%d level=%d)\n", prettyprint(terms[index]), prefixlevel, postfixlevel, infixlevel, infos[index].level);+ print("Parse error when parsing operator %S (prefix=%d, postfix=%d, infix=%d level=%d)\n", prettyprint(terms[index], 0, 0, 0), prefixlevel, postfixlevel, infixlevel, infos[index].level); syntaxerror_parser("parseoperators");}
}
--- a/prettyprint.c
+++ b/prettyprint.c
@@ -1,15 +1,16 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
-Rune *prettyprintlist(Term *, Rune *, int);
-Rune *printlist(Term *);
+Rune *prettyprintlist(Term *, Rune *, int, int, int, int);
+Rune *printlist(Term *, int, int, int);
int islist(Term *);
Rune *
-prettyprint(Term *t)
+prettyprint(Term *t, int quoted, int ignoreops, int numbervars)
{Rune *result;
Rune *args;
@@ -16,9 +17,9 @@
switch(t->tag){case CompoundTerm:
- args = printlist(t);
+ args = printlist(t, quoted, ignoreops, numbervars);
if(args == nil){- args = prettyprintlist(t->children, L", ", 0);
+ args = prettyprintlist(t->children, L", ", 0, quoted, ignoreops, numbervars);
result = runesmprint("%S(%S)", t->text, args);free(args);
}else
@@ -45,7 +46,7 @@
}
Rune *
-prettyprintlist(Term *t, Rune *sep, int end)
+prettyprintlist(Term *t, Rune *sep, int end, int quoted, int ignoreops, int numbervars)
{ if(t == nil){if(end)
@@ -54,8 +55,8 @@
return runesmprint("");}
- Rune *str = prettyprint(t);
- Rune *rest = prettyprintlist(t->next, sep, end);
+ Rune *str = prettyprint(t, quoted, ignoreops, numbervars);
+ Rune *rest = prettyprintlist(t->next, sep, end, quoted, ignoreops, numbervars);
Rune *result;
if(t->next != nil)
@@ -70,7 +71,7 @@
/* printlist prints a list's elements but not the surrounding [ and ] */
Rune *
-printlist(Term *list)
+printlist(Term *list, int quoted, int ignoreops, int numbervars)
{if(list->tag != CompoundTerm || list->arity != 2 || runestrcmp(L".", list->text) != 0)
return nil;
@@ -78,20 +79,20 @@
Term *head = list->children;
Term *tail = head->next;
- Rune *headstr = prettyprint(head);
+ Rune *headstr = prettyprint(head, quoted, ignoreops, numbervars);
Rune *tailstr = nil;
Rune *result;
if(tail->tag == CompoundTerm && tail->arity == 2 && runestrcmp(L".", tail->text) == 0){- tailstr = printlist(tail);
+ tailstr = printlist(tail, quoted, ignoreops, numbervars);
result = runesmprint("%S, %S", headstr, tailstr); }else if(tail->tag == AtomTerm && runestrcmp(L"[]", tail->text) == 0){ result = runesmprint("%S", headstr); }else{- tailstr = prettyprint(tail);
+ tailstr = prettyprint(tail, quoted, ignoreops, numbervars);
result = runesmprint("%S | %S", headstr, tailstr);}
free(headstr);
free(tailstr);
return result;
-}
\ No newline at end of file
+}
--- a/repl.c
+++ b/repl.c
@@ -13,7 +13,7 @@
int fd = 0; /* Standard input */
while(1){ print("?- ");- Term *query = parse(fd, 1);
+ Term *query = parse(fd, nil, 1);
Binding *bindings = nil;
Choicepoint *choicestack = nil;
int success;
@@ -28,7 +28,7 @@
while(bindings){ print(" %S = %S%s", bindings->name,
- prettyprint(bindings->value),
+ prettyprint(bindings->value, 0, 0, 0),
bindings->next ? " ,\n" : "");
bindings = bindings->next;
}
--- a/stdlib.pl
+++ b/stdlib.pl
@@ -105,3 +105,35 @@
syntax_error(Error) :-
throw(error(syntax_error(Error), _)).
+
+% Input and output
+
+read_term(Term, Options) :-
+ current_input(S),
+ read_term(S, Term, Options).
+
+read(Term) :-
+ current_input(S),
+ read_term(S, Term, []).
+
+write_term(Term, Options) :-
+ current_output(S),
+ write_term(S, Term, Options).
+
+write(Term) :-
+ current_output(S),
+ write_term(S, Term, [numbervars(true)]).
+
+writeq(Term) :-
+ current_output(S),
+ write_term(S, Term, [quoted(true), numbervars(true)]).
+
+writeq(S, Term) :-
+ write_term(S, Term, [quoted(true), numbervars(true)]).
+
+write_canonical(Term) :-
+ current_output(S),
+ write_term(S, Term, [quoted(true), ignore_ops(true)]).
+
+write_canonical(S, Term) :-
+ write_term(S, Term, [quoted(true), ignore_ops(true)]).
--- a/streams.c
+++ b/streams.c
@@ -1,5 +1,6 @@
#include <u.h>
#include <libc.h>
+#include <bio.h>
#include "dat.h"
#include "fns.h"
@@ -9,6 +10,7 @@
struct Stream
{ulong fd;
+ Biobuf *bio;
int type;
int mode;
int nalias;
@@ -31,7 +33,7 @@
static Stream *currentinput;
static Stream *currentoutput;
-Stream *openstreamfd(int, int, int);
+Stream *openstreamfd(int, Biobuf *, int, int);
Stream *getstreambyfd(int);
Stream *getstreambyalias(Rune *);
Stream *getstream(Term *);
@@ -39,8 +41,14 @@
void
initstreams(void)
{- currentinput = openstreamfd(0, TextStream, ReadStream);
- currentoutput = openstreamfd(1, TextStream, WriteStream);
+ int infd = dup(0, -1);
+ int outfd = dup(1, -1);
+
+ Biobuf *bioin = Bfdopen(infd, OREAD);
+ Biobuf *bioout = Bfdopen(outfd, OWRITE);
+
+ currentinput = openstreamfd(infd, bioin, TextStream, ReadStream);
+ currentoutput = openstreamfd(outfd, bioout, TextStream, WriteStream);
}
int
@@ -69,7 +77,13 @@
*stream = permissionerror(L"open", L"source_sink", mkatom(sourcesink));
return 1;
}
- Stream *s = openstreamfd(fd, TextStream, smode);
+ Biobuf *bio = Bfdopen(fd, omode);
+ if(bio == nil){+ *stream = permissionerror(L"open", L"source_sink", mkatom(sourcesink));
+ return 1;
+ }
+
+ Stream *s = openstreamfd(fd, bio, TextStream, smode);
*stream = mknumber(NumberInt, s->fd, 0);
return 0;
}
@@ -81,6 +95,9 @@
if(s == nil)
return;
+ Bterm(s->bio);
+ close(s->fd);
+
Stream *tmp;
Stream *prev = nil;
for(tmp = streams; tmp != nil; tmp = tmp->next){@@ -154,11 +171,66 @@
return 0;
}
+int
+istextstream(Term *t)
+{+ Stream *s = getstream(t);
+ if(s && s->type == TextStream)
+ return 1;
+ else
+ return 0;
+}
+
+int
+isbinarystream(Term *t)
+{+ Stream *s = getstream(t);
+ if(s && s->type == BinaryStream)
+ return 1;
+ else
+ return 0;
+}
+
+int
+readterm(Term *stream, Term *options, Term **term)
+{+ USED(options);
+
+ Stream *s = getstream(stream);
+ if(s == nil){+ *term = existenceerror(L"stream", stream);
+ return 1;
+ }
+ print(": ");+ *term = parse(0, s->bio, 1);
+
+ return 0;
+}
+
+void
+writeterm(Term *stream, Term *options, Term *term)
+{+ USED(options);
+
+ Stream *s = getstream(stream);
+ if(s == nil)
+ return;
+
+ int quoted = 0;
+ int ignoreops = 0;
+ int numbervars = 0;
+
+ Rune *output = prettyprint(term, quoted, ignoreops, numbervars);
+ Bprint(s->bio, "%S", output);
+ Bflush(s->bio);
+}
+
Stream *
-openstreamfd(int fd, int type, int mode)
+openstreamfd(int fd, Biobuf *bio, int type, int mode)
{Stream *s = malloc(sizeof(Stream));
s->fd = fd;
+ s->bio = bio;
s->type = type;
s->mode = mode;
s->nalias = 0;
@@ -201,4 +273,5 @@
else if(t->tag == AtomTerm)
s = getstreambyalias(t->text);
return s;
-}
\ No newline at end of file
+}
+