mhbuild: Avoid a dot on a line on its own

mhbuild's quoted-printable encoder breaks lines to have at most
CPERLIN chars. If the it happens that the last character on the
line is a dot (`.') and the line is broken just before it, then
the following line contains nothing but one single dot. This
currently leads to problems in mmh ... but it may cause problems
to other mail software as well. Hence we avoid it by encoding
any dot at the beginning of a line, just to be sure.

diff --git a/uip/mhoutsbr.c b/uip/mhoutsbr.c
index 21c2e26318b68f5d5011bcc73f29f2d6a3188ff3..ba883196108c77a42dd5e81257615d9cc2a51005 100644 (file)
--- a/uip/mhoutsbr.c
+++ b/uip/mhoutsbr.c
@@ -241,8 +241,16 @@ writeQuoted(CT ct, FILE *out)
                                break;
 
                        default:
-                               if (*cp < '!' || *cp > '~')
+                               if (*cp < '!' || *cp > '~') {
                                        goto three_print;
+                               }
+                               if (n == 0 && *cp == '.') {
+                                       /*
+                                       ** encode dot at start of line,
+                                       ** because it could be alone ...
+                                       */
+                                       goto three_print;
+                               }
                                putc(*cp, out);
                                n++;
                                break;