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-rw-r--r--contrib/gperf/src/list-node.cc101
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diff --git a/contrib/gperf/src/list-node.cc b/contrib/gperf/src/list-node.cc
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+/* Creates and initializes a new list node.
+ Copyright (C) 1989-1998 Free Software Foundation, Inc.
+ written by Douglas C. Schmidt (schmidt@ics.uci.edu)
+
+This file is part of GNU GPERF.
+
+GNU GPERF 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; either version 1, or (at your option)
+any later version.
+
+GNU GPERF 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 GNU GPERF; see the file COPYING. If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111, USA. */
+
+#include "list-node.h"
+
+#include <stdio.h>
+#include <stdlib.h> /* declares exit() */
+#include "options.h"
+#include "trace.h"
+
+/* Sorts the key set alphabetically to speed up subsequent operations.
+ Uses insertion sort since the set is probably quite small. */
+
+inline void
+List_Node::set_sort (char *base, int len)
+{
+ T (Trace t ("List_Node::set_sort");)
+ int i, j;
+
+ for (i = 0, j = len - 1; i < j; i++)
+ {
+ char curr, tmp;
+
+ for (curr = i + 1, tmp = base[curr]; curr > 0 && tmp < base[curr-1]; curr--)
+ base[curr] = base[curr - 1];
+
+ base[curr] = tmp;
+
+ }
+}
+
+/* Initializes a List_Node. This requires obtaining memory for the CHAR_SET
+ initializing them using the information stored in the KEY_POSITIONS array in Options,
+ and checking for simple errors. It's important to note that KEY and REST are
+ both pointers to the different offsets into the same block of dynamic memory pointed
+ to by parameter K. The data member REST is used to store any additional fields
+ of the input file (it is set to the "" string if Option[TYPE] is not enabled).
+ This is useful if the user wishes to incorporate a lookup structure,
+ rather than just an array of keys. Finally, KEY_NUMBER contains a count
+ of the total number of keys seen so far. This is used to initialize
+ the INDEX field to some useful value. */
+
+List_Node::List_Node (char *k, int len): link (0), next (0),
+ key (k), rest (option[TYPE] ? k + len + 1 : ""), length (len), index (0)
+{
+ T (Trace t ("List_Node::List_Node");)
+ char *ptr = new char[(option[ALLCHARS] ? len : option.get_max_keysig_size ()) + 1];
+ char *key_set = ptr;
+ k[len] = '\0'; /* Null terminate KEY to separate it from REST. */
+
+ if (option[ALLCHARS]) /* Use all the character position in the KEY. */
+ for (; *k; k++, ptr++)
+ ++occurrences[(unsigned char)(*ptr = *k)];
+ else /* Only use those character positions specified by the user. */
+ {
+ int i;
+
+ /* Iterate thru the list of key_positions, initializing occurrences table
+ and char_set (via char * pointer ptr). */
+
+ for (option.reset (); (i = option.get ()) != EOS; )
+ {
+ if (i == WORD_END) /* Special notation for last KEY position, i.e. '$'. */
+ *ptr = key[len - 1];
+ else if (i <= len) /* Within range of KEY length, so we'll keep it. */
+ *ptr = key[i - 1];
+ else /* Out of range of KEY length, so we'll just skip it. */
+ continue;
+ ++occurrences[(unsigned char)(*ptr++)];
+ }
+
+ /* Didn't get any hits and user doesn't want to consider the
+ keylength, so there are essentially no usable hash positions! */
+ if (ptr == char_set && option[NOLENGTH])
+ {
+ fprintf (stderr, "Can't hash keyword %s with chosen key positions.\n", key);
+ exit (1);
+ }
+ }
+ *ptr = '\0'; /* Terminate this bastard.... */
+ /* Sort the KEY_SET items alphabetically. */
+ set_sort (key_set, ptr - key_set);
+ char_set = key_set;
+}
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