1 files changed, 66 insertions, 13 deletions

diff --git a/src/targets/unblc.c b/src/targets/unblc.c
index 2d10418..3c4beb2 100644
--- a/src/targets/unblc.c
+++ b/src/targets/unblc.c
@@ -9,40 +9,93 @@
 #include <parse.h>
 #include <log.h>
 
-static void fprint_unblc(struct term *term, struct bloc_parsed *bloc,
-			 FILE *file)
+struct context {
+	enum { WRITE_BITS, WRITE_ASCII } type;
+	FILE *file;
+	char *byte;
+	int *bit;
+};
+
+static void write_context(struct context *context, const char *bits)
+{
+	if (context->type == WRITE_ASCII) {
+		fprintf(context->file, "%s", bits);
+		return;
+	}
+
+	// WRITE_BITS
+	for (const char *p = bits; *p; p++) {
+		if (*context->bit > 7) { // flush byte
+			fwrite(context->byte, 1, 1, context->file);
+			*context->byte = 0;
+			*context->bit = 0;
+		}
+
+		// TODO: which endianness should be default?
+		if (*p & 1)
+			*context->byte |= 1UL << *context->bit;
+		(*context->bit)++;
+	}
+}
+
+static void write_unblc(struct term *term, struct bloc_parsed *bloc,
+			struct context *context)
 {
 	switch (term->type) {
 	case ABS:
-		fprintf(file, "00");
-		fprint_unblc(term->u.abs.term, bloc, file);
+		write_context(context, "00");
+		write_unblc(term->u.abs.term, bloc, context);
 		break;
 	case APP:
-		fprintf(file, "01");
-		fprint_unblc(term->u.app.lhs, bloc, file);
-		fprint_unblc(term->u.app.rhs, bloc, file);
+		write_context(context, "01");
+		write_unblc(term->u.app.lhs, bloc, context);
+		write_unblc(term->u.app.rhs, bloc, context);
 		break;
 	case VAR:
 		for (int i = 0; i <= term->u.var.index; i++)
-			fprintf(file, "1");
-		fprintf(file, "0");
+			write_context(context, "1");
+		write_context(context, "0");
 		break;
 	case REF:
 		if (term->u.ref.index + 1 >= bloc->length)
 			fatal("invalid ref index %ld\n", term->u.ref.index);
-		fprint_unblc(bloc->entries[term->u.ref.index], bloc, file);
+		write_unblc(bloc->entries[term->u.ref.index], bloc, context);
 		break;
 	default:
 		fatal("invalid type %d\n", term->type);
 	}
 }
 
-static void write_unblc(struct bloc_parsed *bloc, FILE *file)
+static void write_unblc_ascii(struct bloc_parsed *bloc, FILE *file)
 {
-	fprint_unblc(bloc->entries[bloc->length - 1], bloc, file);
+	struct context context = {
+		.type = WRITE_ASCII,
+		.file = file,
+	};
+	write_unblc(bloc->entries[bloc->length - 1], bloc, &context);
+}
+
+static void write_unblc_bits(struct bloc_parsed *bloc, FILE *file)
+{
+	char byte = 0;
+	int bit = 0;
+	struct context context = {
+		.type = WRITE_BITS,
+		.file = file,
+		.byte = &byte,
+		.bit = &bit,
+	};
+	write_unblc(bloc->entries[bloc->length - 1], bloc, &context);
+	if (bit)
+		fwrite(&byte, 1, 1, file);
 }
 
 struct target_spec target_unblc = {
 	.name = "unblc",
-	.exec = write_unblc,
+	.exec = write_unblc_ascii,
+};
+
+struct target_spec target_unbblc = {
+	.name = "unbblc",
+	.exec = write_unblc_bits,
 };