util-vserver-0.30.208

[util-vserver.git] / ensc_vector / vector-searchselforg.c

diff --git a/ensc_vector/vector-searchselforg.c b/ensc_vector/vector-searchselforg.c
new file mode 100644 (file)
index 0000000..420e367
--- /dev/null
+++ b/ensc_vector/vector-searchselforg.c
@@ -0,0 +1,71 @@
+// $Id: vector-searchselforg.c,v 1.1 2005/03/17 14:47:21 ensc Exp $    --*- c -*--
+
+// Copyright (C) 2005 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
+//  
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; version 2 of the License.
+//  
+// This program 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 General Public License for more details.
+//  
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "vector.h"
+#include "vector-internal.h"
+
+#include <string.h>
+#include <assert.h>
+#include <stdbool.h>
+
+void *
+Vector_searchSelfOrg(struct Vector *vec, void const *key,
+                    int (*compare)(const void *, const void *),
+                    VectorSelfOrgMethod method)
+{
+  char * const start_ptr = vec->data;
+  char * const end_ptr   = start_ptr + vec->count*vec->elem_size;
+  char         *ptr      = start_ptr;
+  
+  for (; ptr<end_ptr && compare(ptr, key)!=0; )
+    ptr += vec->elem_size;
+
+  if      (end_ptr  <= ptr) ptr = 0;
+  else if (start_ptr < ptr) {
+    char               tmp[vec->elem_size];
+    memcpy(tmp, ptr, vec->elem_size);
+
+    assert(ptr >= start_ptr+vec->elem_size);
+
+    switch (method) {
+      case vecMOVE_FRONT               :
+       memmove(start_ptr+vec->elem_size, start_ptr, ptr - start_ptr);
+
+       ptr = start_ptr;
+       break;
+       
+      case vecSHIFT_ONCE               :
+       memmove(ptr, ptr  - vec->elem_size, vec->elem_size);
+       ptr -= vec->elem_size;
+       break;
+
+      default          :
+       assert(false);
+       ptr   = 0;
+    }
+
+    memcpy (ptr, tmp, vec->elem_size);
+  }
+
+  return ptr;
+}
+