nqdasm: Factor out disassembly code from command line parsing

1 files changed, 21 insertions, 16 deletions

diff --git a/nqdasm.c b/nqdasm.c
index 0ecc5b1..3245570 100644
--- a/nqdasm.c
+++ b/nqdasm.c
@@ -39,6 +39,26 @@ static void print_operand(FILE *out, unsigned bits, const struct operand *op)
 	}
 }
 
+static void disassemble(FILE *in, FILE *out)
+{
+	unsigned bits;
+	while (fscanf(in, " %x\n", &bits) > 0) {
+		const struct mnemonic *m = match_instruction(bits);
+		if (!m) {
+			fprintf(out, "\t.word   0x%04x\n", bits);
+			continue;
+		}
+
+		fprintf(out, "\t%s", m->mnem);
+		for (int i = 0; i < 3 && m->operands[i].type; i++) {
+			if (i) fprintf(out, ", ");
+			else   fprintf(out, "%*s", 8 - (int)strlen(m->mnem), "");
+			print_operand(out, bits, m->operands + i);
+		}
+		fprintf(out, "\n");
+	}
+}
+
 static void usage(const char *progname)
 {
 	printf("usage: %s [-o output] [input]\n", progname);
@@ -88,22 +108,7 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	unsigned bits;
-	while (fscanf(in, " %x\n", &bits) > 0) {
-		const struct mnemonic *m = match_instruction(bits);
-		if (!m) {
-			fprintf(out, "\t.word   0x%04x\n", bits);
-			continue;
-		}
-
-		fprintf(out, "\t%s", m->mnem);
-		for (int i = 0; i < 3 && m->operands[i].type; i++) {
-			if (i) fprintf(out, ", ");
-			else   fprintf(out, "%*s", 8 - (int)strlen(m->mnem), "");
-			print_operand(out, bits, m->operands + i);
-		}
-		fprintf(out, "\n");
-	}
+	disassemble(in, out);
 
 	fclose(in);
 	fclose(out);