Initial import of the CDE 2.1.30 sources from the Open Group.

cde/programs/dtinfo/DtMmdb/storage/chunks_index.C

@@ -0,0 +1,149 @@
+/*
+ * $XConsortium: chunks_index.cc /main/4 1996/07/18 14:52:47 drk $
+ *
+ * Copyright (c) 1993 HAL Computer Systems International, Ltd.
+ * All rights reserved.  Unpublished -- rights reserved under
+ * the Copyright Laws of the United States.  USE OF A COPYRIGHT
+ * NOTICE IS PRECAUTIONARY ONLY AND DOES NOT IMPLY PUBLICATION
+ * OR DISCLOSURE.
+ * 
+ * THIS SOFTWARE CONTAINS CONFIDENTIAL INFORMATION AND TRADE
+ * SECRETS OF HAL COMPUTER SYSTEMS INTERNATIONAL, LTD.  USE,
+ * DISCLOSURE, OR REPRODUCTION IS PROHIBITED WITHOUT THE
+ * PRIOR EXPRESS WRITTEN PERMISSION OF HAL COMPUTER SYSTEMS
+ * INTERNATIONAL, LTD.
+ * 
+ *                         RESTRICTED RIGHTS LEGEND
+ * Use, duplication, or disclosure by the Government is subject
+ * to the restrictions as set forth in subparagraph (c)(l)(ii)
+ * of the Rights in Technical Data and Computer Software clause
+ * at DFARS 252.227-7013.
+ *
+ *          HAL COMPUTER SYSTEMS INTERNATIONAL, LTD.
+ *                  1315 Dell Avenue
+ *                  Campbell, CA  95008
+ * 
+ */
+
+
+
+#include "storage/chunks_index.h"
+
+/****************************************************/
+// record and comparison functions for string index
+/****************************************************/
+
+Boolean str_index_record_ls(const void* o1, const void* o2)
+{
+   const str_index_record_t* x = (str_index_record_t*)o1;
+   const str_index_record_t* y = (str_index_record_t*)o2;
+
+/*
+MESSAGE(cerr, "LS");
+debug(cerr, x -> str_offset);
+debug(cerr, x -> loc);
+debug(cerr, y -> str_offset);
+debug(cerr, y -> loc);
+MESSAGE(cerr, "");
+*/
+
+   return ( x -> str_offset < y -> str_offset ) ? true : false;
+}
+
+Boolean str_index_record_eq(const void* o1, const void* o2)
+{
+   const str_index_record_t* x = (str_index_record_t*)o1;
+   const str_index_record_t* y = (str_index_record_t*)o2;
+
+/*
+MESSAGE(cerr, "EQ");
+debug(cerr, x -> str_offset);
+debug(cerr, x -> loc);
+debug(cerr, y -> str_offset);
+debug(cerr, y -> loc);
+MESSAGE(cerr, "");
+*/
+
+   return ( x -> str_offset == y -> str_offset ) ? true : false;
+}
+
+///////////////////////////////////////////////////////
+//
+///////////////////////////////////////////////////////
+
+chunks_index::chunks_index(abs_storage* store, 
+                           mmdb_pos_t loc) : 
+v_index_imp(str_index_record_eq, str_index_record_ls),
+v_storage_ptr(store), v_initial_loc(loc)
+{
+   str_index_record_tPtr* vector = 0;
+   int vector_sz = 0;
+
+   if ( v_storage_ptr == 0 || v_initial_loc == 0 )
+      return ;
+
+   ((page_storage*)v_storage_ptr) -> get_str_locs(loc, vector, vector_sz);
+
+/*
+MESSAGE(cerr, "vector:");
+debug(cerr, vector_sz);
+for ( int i=0; i<vector_sz; i++ ) {
+debug(cerr, i);
+debug(cerr, vector[i] -> loc);
+debug(cerr, vector[i] -> str_offset);
+}
+*/
+
+
+   binary_insert(vector, 0, vector_sz-1);
+   delete vector;
+}
+
+chunks_index::~chunks_index() 
+{
+    v_index_imp.del_elements(delete_str_index_record);
+}
+
+/***************************************************/
+// Note: given that the keys in vector are non-
+//       decreasing, it is optimal to binarilly
+//       insert keys to obtained a
+//       balanced binary search tree.
+//
+//       get_str_locs() returns a non-decreasing
+//       key vector
+/***************************************************/
+
+Boolean
+chunks_index::binary_insert(str_index_record_tPtr* vector,
+                            int left, int right)
+{
+   if ( left > right )
+     return true;
+
+   int middle = (right + 1 - left) / 2 + left;
+//debug(cerr, middle);
+   v_index_imp.insert(vector[middle]);
+
+   Boolean ok1 = binary_insert(vector, left, middle-1);
+   Boolean ok2 = binary_insert(vector, middle+1, right);
+
+   return  ( ok1 == true && ok2 == true ) ? true : false;
+}
+
+
+str_index_record_t* 
+chunks_index::chunk_location( int offset )
+{
+   str_index_record_t key(offset);
+
+   str_index_record_t* anchor = (str_index_record_t*)
+        v_index_imp.smaller_member((root*)&key);
+
+   if ( anchor == 0 ) {
+      throw(stringException("chunk_location(): no smaller member"));
+   }
+
+   return anchor;
+}
+