diff options
Diffstat (limited to 'libmailutils/sockaddr/insert.c')
-rw-r--r-- | libmailutils/sockaddr/insert.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/libmailutils/sockaddr/insert.c b/libmailutils/sockaddr/insert.c new file mode 100644 index 000000000..dbac151c1 --- /dev/null +++ b/libmailutils/sockaddr/insert.c @@ -0,0 +1,64 @@ +/* GNU Mailutils -- a suite of utilities for electronic mail + Copyright (C) 2011 Free Software Foundation, Inc. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 3 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General + Public License along with this library. If not, see + <http://www.gnu.org/licenses/>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <stdlib.h> +#include <mailutils/sockaddr.h> + +static void +set_next (struct mu_sockaddr *sp, struct mu_sockaddr *tgt) +{ + for (; sp->next; sp = sp->next) + ; + sp->next = tgt; + if (tgt) + tgt->prev = sp; +} + +struct mu_sockaddr * +mu_sockaddr_insert (struct mu_sockaddr *anchor, struct mu_sockaddr *addr, + int before) +{ + struct mu_sockaddr *ret = anchor; + + if (!anchor) + { + addr->prev = NULL; + set_next (addr, NULL); + return addr; + } + + if (before) + { + if (anchor->prev) + anchor = anchor->prev; + else + { + addr->prev = NULL; + set_next (addr, anchor); + return addr; + } + } + + set_next (addr, anchor->next); + anchor->next = addr; + addr->prev = anchor; + return ret; +} |