Start adding support for read_term and write_term

1 files changed, 72 insertions, 4 deletions

diff --git a/builtins.c b/builtins.c
index 46b761b..0fede28 100644
--- 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(builtincurrentinput);
 BuiltinProto(builtincurrentoutput);
 BuiltinProto(builtinsetinput);
 BuiltinProto(builtinsetoutput);
+BuiltinProto(builtinreadterm);
+BuiltinProto(builtinwriteterm);
 
 int compareterms(Term *, Term *);
 
@@ -116,6 +119,10 @@ findbuiltin(Term *goal)
 		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 @@ builtinthrow(Term *database, Term *goal, Goal **goals, Choicepoint **choicestack
 
 	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 @@ builtinthrow(Term *database, Term *goal, Goal **goals, Choicepoint **choicestack
 		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 @@ int
 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 @@ builtinsetoutput(Term *database, Term *goal, Goal **goals, Choicepoint **choices
 
 	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;
+}
+