length check

[c128-kasse] / general.c

diff --git a/general.c b/general.c
index 9f0c6c6072411284eadc8f6e653b3922a3ae0a34..03bc576107e548adb5fc980a811fecaba61fbb37 100644 (file)
--- a/general.c
+++ b/general.c
@@ -29,7 +29,13 @@ char *get_input() {
        return output;
 }
 
-char * format_euro(char * s, int cent){
+char * format_euro(char * s, int maxlen, int cent){
+       int tmp = cent;
+       int len = 5; // 1 char at least + 4 (== strlen(",EUR"))
+       while ((tmp/=10) > 0)
+               len++;
+       if (len>maxlen)
+               return NULL;
        sprintf(s, "%d,%dEUR", cent/100, cent%100);
        return s;
 }