2 files changed, 11 insertions, 0 deletions
diff --git a/config.c b/config.c
index 2e644b5..dbf7a64 100644
--- a/config.c
+++ b/config.c
@@ -40,6 +40,12 @@ struct hcalc_config {
 char *home_dir = NULL;
 char config_path[MAX_HOME];		/* ludicrous size */
 
+void validate_numbers(void) {
+	if(!number_is_ok(value))  value = 0;
+	if(!number_is_ok(saved))  saved = 0;
+	if(!number_is_ok(stored)) stored = 0;
+}
+
 size_t filesize(FILE *f) {
 	struct stat st;
 
@@ -121,6 +127,8 @@ void load_config(void) {
 	winsize = conf.winsize;
 	base = conf.base;
 	quiet = conf.quiet;
+
+	validate_numbers();
 }
 
 void save_config(void) {
@@ -142,6 +150,8 @@ void save_config(void) {
 		return;
 	}
 
+	validate_numbers();
+
 	memcpy(conf.signature, SIGNATURE, SIGLEN);
 	conf.doublesize = sizeof(double);
 	conf.value = value;
diff --git a/hcalc.h b/hcalc.h
index 44d4cc0..06a8428 100644
--- a/hcalc.h
+++ b/hcalc.h
@@ -63,5 +63,6 @@ void show_value(void);
 void bell(void);
 void copy(void);
 void paste(void);
+int number_is_ok(double n);
 
 #define MAXCHARS 15