# HG changeset patch
# User Timo Sirainen <timo.sirainen@dovecot.fi>
# Date 1500472158 -10800
# Node ID 125e78e85bcc71e0d273db232be561d57c6fd24f
# Parent  239bc902f6dae64343d69a366a44d0ca45e6c633
lib-mail: Make sure mail_user_hash() won't return 0 as the hash.

It doesn't seem to actually happen, but this makes sure of it.

diff -r 239bc902f6da -r 125e78e85bcc src/lib-mail/mail-user-hash.c
--- a/src/lib-mail/mail-user-hash.c	Thu Jul 06 15:45:24 2017 +0300
+++ b/src/lib-mail/mail-user-hash.c	Wed Jul 19 16:49:18 2017 +0300
@@ -42,6 +42,12 @@
 	} T_END;
 	for (i = 0; i < sizeof(hash); i++)
 		hash = (hash << CHAR_BIT) | md5[i];
+	if (hash == 0) {
+		/* Make sure we don't return the hash as 0, since it's often
+		   treated in a special way that won't work well. For example
+		   trying to insert it into a hash table will assert-crash. */
+		hash = 1;
+	}
 	return hash;
 }
 
diff -r 239bc902f6da -r 125e78e85bcc src/lib-mail/mail-user-hash.h
--- a/src/lib-mail/mail-user-hash.h	Thu Jul 06 15:45:24 2017 +0300
+++ b/src/lib-mail/mail-user-hash.h	Wed Jul 19 16:49:18 2017 +0300
@@ -2,7 +2,7 @@
 #define MAIL_USER_HASH
 
 /* Return a hash for username, based on given format. The format can use
-   %n, %d and %u variables. */
+   %n, %d and %u variables. The returned hash is never 0. */
 unsigned int mail_user_hash(const char *username, const char *format);
 
 #endif