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authorLorry Tar Creator <lorry-tar-importer@baserock.org>2014-12-23 14:38:46 +0000
committer <>2015-05-26 15:48:41 +0000
commit5500a97a2ad1735db5b35bc51cfb825c1f4c38df (patch)
treecc6e777c26142b88456ff03a672e1cb69215fc32 /libiberty/insque.c
downloadbinutils-tarball-master.tar.gz
Imported from /home/lorry/working-area/delta_binutils-tarball/binutils-2.25.tar.bz2.HEADbinutils-2.25master
Diffstat (limited to 'libiberty/insque.c')
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diff --git a/libiberty/insque.c b/libiberty/insque.c
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+/* insque(3C) routines
+ This file is in the public domain. */
+
+/*
+
+@deftypefn Supplemental void insque (struct qelem *@var{elem}, @
+ struct qelem *@var{pred})
+@deftypefnx Supplemental void remque (struct qelem *@var{elem})
+
+Routines to manipulate queues built from doubly linked lists. The
+@code{insque} routine inserts @var{elem} in the queue immediately
+after @var{pred}. The @code{remque} routine removes @var{elem} from
+its containing queue. These routines expect to be passed pointers to
+structures which have as their first members a forward pointer and a
+back pointer, like this prototype (although no prototype is provided):
+
+@example
+struct qelem @{
+ struct qelem *q_forw;
+ struct qelem *q_back;
+ char q_data[];
+@};
+@end example
+
+@end deftypefn
+
+*/
+
+
+struct qelem {
+ struct qelem *q_forw;
+ struct qelem *q_back;
+};
+
+
+void
+insque (struct qelem *elem, struct qelem *pred)
+{
+ elem -> q_forw = pred -> q_forw;
+ pred -> q_forw -> q_back = elem;
+ elem -> q_back = pred;
+ pred -> q_forw = elem;
+}
+
+
+void
+remque (struct qelem *elem)
+{
+ elem -> q_forw -> q_back = elem -> q_back;
+ elem -> q_back -> q_forw = elem -> q_forw;
+}