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-rw-r--r--runtime/Makefile.am2
-rw-r--r--runtime/hashtable/Makefile26
-rw-r--r--runtime/hashtable/hashtable.c275
-rw-r--r--runtime/hashtable/hashtable.h199
-rw-r--r--runtime/hashtable/hashtable_itr.c188
-rw-r--r--runtime/hashtable/hashtable_itr.h112
-rw-r--r--runtime/hashtable/hashtable_private.h85
-rw-r--r--runtime/hashtable/hashtable_utility.c71
-rw-r--r--runtime/hashtable/hashtable_utility.h55
-rw-r--r--runtime/hashtable/tester.c270
10 files changed, 1283 insertions, 0 deletions
diff --git a/runtime/Makefile.am b/runtime/Makefile.am
index 01b224e7..d657b6ca 100644
--- a/runtime/Makefile.am
+++ b/runtime/Makefile.am
@@ -95,6 +95,8 @@ librsyslog_la_SOURCES = \
../parse.c \
../parse.h \
\
+ hashtable/hashtable.c \
+ \
../outchannel.c \
../outchannel.h \
../template.c \
diff --git a/runtime/hashtable/Makefile b/runtime/hashtable/Makefile
new file mode 100644
index 00000000..3b7b5e9f
--- /dev/null
+++ b/runtime/hashtable/Makefile
@@ -0,0 +1,26 @@
+
+tester: hashtable.o tester.o hashtable_itr.o
+ gcc -g -Wall -O -lm -o tester hashtable.o hashtable_itr.o tester.o
+
+all: tester old_tester
+
+tester.o: tester.c
+ gcc -g -Wall -O -c tester.c -o tester.o
+
+old_tester: hashtable_powers.o tester.o hashtable_itr.o
+ gcc -g -Wall -O -o old_tester hashtable_powers.o hashtable_itr.o tester.o
+
+hashtable_powers.o: hashtable_powers.c
+ gcc -g -Wall -O -c hashtable_powers.c -o hashtable_powers.o
+
+hashtable.o: hashtable.c
+ gcc -g -Wall -O -c hashtable.c -o hashtable.o
+
+hashtable_itr.o: hashtable_itr.c
+ gcc -g -Wall -O -c hashtable_itr.c -o hashtable_itr.o
+
+tidy:
+ rm *.o
+
+clean: tidy
+ rm -f tester old_tester
diff --git a/runtime/hashtable/hashtable.c b/runtime/hashtable/hashtable.c
new file mode 100644
index 00000000..a10e3bc6
--- /dev/null
+++ b/runtime/hashtable/hashtable.c
@@ -0,0 +1,275 @@
+/* Copyright (C) 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+/* taken from http://www.cl.cam.ac.uk/~cwc22/hashtable/ */
+
+#include "hashtable.h"
+#include "hashtable_private.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
+/*
+Credit for primes table: Aaron Krowne
+ http://br.endernet.org/~akrowne/
+ http://planetmath.org/encyclopedia/GoodHashTablePrimes.html
+*/
+static const unsigned int primes[] = {
+53, 97, 193, 389,
+769, 1543, 3079, 6151,
+12289, 24593, 49157, 98317,
+196613, 393241, 786433, 1572869,
+3145739, 6291469, 12582917, 25165843,
+50331653, 100663319, 201326611, 402653189,
+805306457, 1610612741
+};
+const unsigned int prime_table_length = sizeof(primes)/sizeof(primes[0]);
+const float max_load_factor = 0.65;
+
+/*****************************************************************************/
+struct hashtable *
+create_hashtable(unsigned int minsize,
+ unsigned int (*hashf) (void*),
+ int (*eqf) (void*,void*))
+{
+ struct hashtable *h;
+ unsigned int pindex, size = primes[0];
+ /* Check requested hashtable isn't too large */
+ if (minsize > (1u << 30)) return NULL;
+ /* Enforce size as prime */
+ for (pindex=0; pindex < prime_table_length; pindex++) {
+ if (primes[pindex] > minsize) { size = primes[pindex]; break; }
+ }
+ h = (struct hashtable *)malloc(sizeof(struct hashtable));
+ if (NULL == h) return NULL; /*oom*/
+ h->table = (struct entry **)malloc(sizeof(struct entry*) * size);
+ if (NULL == h->table) { free(h); return NULL; } /*oom*/
+ memset(h->table, 0, size * sizeof(struct entry *));
+ h->tablelength = size;
+ h->primeindex = pindex;
+ h->entrycount = 0;
+ h->hashfn = hashf;
+ h->eqfn = eqf;
+ h->loadlimit = (unsigned int) ceil(size * max_load_factor);
+ return h;
+}
+
+/*****************************************************************************/
+unsigned int
+hash(struct hashtable *h, void *k)
+{
+ /* Aim to protect against poor hash functions by adding logic here
+ * - logic taken from java 1.4 hashtable source */
+ unsigned int i = h->hashfn(k);
+ i += ~(i << 9);
+ i ^= ((i >> 14) | (i << 18)); /* >>> */
+ i += (i << 4);
+ i ^= ((i >> 10) | (i << 22)); /* >>> */
+ return i;
+}
+
+/*****************************************************************************/
+static int
+hashtable_expand(struct hashtable *h)
+{
+ /* Double the size of the table to accomodate more entries */
+ struct entry **newtable;
+ struct entry *e;
+ struct entry **pE;
+ unsigned int newsize, i, idx;
+ /* Check we're not hitting max capacity */
+ if (h->primeindex == (prime_table_length - 1)) return 0;
+ newsize = primes[++(h->primeindex)];
+
+ newtable = (struct entry **)malloc(sizeof(struct entry*) * newsize);
+ if (NULL != newtable)
+ {
+ memset(newtable, 0, newsize * sizeof(struct entry *));
+ /* This algorithm is not 'stable'. ie. it reverses the list
+ * when it transfers entries between the tables */
+ for (i = 0; i < h->tablelength; i++) {
+ while (NULL != (e = h->table[i])) {
+ h->table[i] = e->next;
+ idx = indexFor(newsize,e->h);
+ e->next = newtable[idx];
+ newtable[idx] = e;
+ }
+ }
+ free(h->table);
+ h->table = newtable;
+ }
+ /* Plan B: realloc instead */
+ else
+ {
+ newtable = (struct entry **)
+ realloc(h->table, newsize * sizeof(struct entry *));
+ if (NULL == newtable) { (h->primeindex)--; return 0; }
+ h->table = newtable;
+ memset(newtable[h->tablelength], 0, newsize - h->tablelength);
+ for (i = 0; i < h->tablelength; i++) {
+ for (pE = &(newtable[i]), e = *pE; e != NULL; e = *pE) {
+ idx = indexFor(newsize,e->h);
+ if (idx == i)
+ {
+ pE = &(e->next);
+ }
+ else
+ {
+ *pE = e->next;
+ e->next = newtable[idx];
+ newtable[idx] = e;
+ }
+ }
+ }
+ }
+ h->tablelength = newsize;
+ h->loadlimit = (unsigned int) ceil(newsize * max_load_factor);
+ return -1;
+}
+
+/*****************************************************************************/
+unsigned int
+hashtable_count(struct hashtable *h)
+{
+ return h->entrycount;
+}
+
+/*****************************************************************************/
+int
+hashtable_insert(struct hashtable *h, void *k, void *v)
+{
+ /* This method allows duplicate keys - but they shouldn't be used */
+ unsigned int idx;
+ struct entry *e;
+ if (++(h->entrycount) > h->loadlimit)
+ {
+ /* Ignore the return value. If expand fails, we should
+ * still try cramming just this value into the existing table
+ * -- we may not have memory for a larger table, but one more
+ * element may be ok. Next time we insert, we'll try expanding again.*/
+ hashtable_expand(h);
+ }
+ e = (struct entry *)malloc(sizeof(struct entry));
+ if (NULL == e) { --(h->entrycount); return 0; } /*oom*/
+ e->h = hash(h,k);
+ idx = indexFor(h->tablelength,e->h);
+ e->k = k;
+ e->v = v;
+ e->next = h->table[idx];
+ h->table[idx] = e;
+ return -1;
+}
+
+/*****************************************************************************/
+void * /* returns value associated with key */
+hashtable_search(struct hashtable *h, void *k)
+{
+ struct entry *e;
+ unsigned int hashvalue, idx;
+ hashvalue = hash(h,k);
+ idx = indexFor(h->tablelength,hashvalue);
+ e = h->table[idx];
+ while (NULL != e)
+ {
+ /* Check hash value to short circuit heavier comparison */
+ if ((hashvalue == e->h) && (h->eqfn(k, e->k))) return e->v;
+ e = e->next;
+ }
+ return NULL;
+}
+
+/*****************************************************************************/
+void * /* returns value associated with key */
+hashtable_remove(struct hashtable *h, void *k)
+{
+ /* TODO: consider compacting the table when the load factor drops enough,
+ * or provide a 'compact' method. */
+
+ struct entry *e;
+ struct entry **pE;
+ void *v;
+ unsigned int hashvalue, idx;
+
+ hashvalue = hash(h,k);
+ idx = indexFor(h->tablelength,hash(h,k));
+ pE = &(h->table[idx]);
+ e = *pE;
+ while (NULL != e)
+ {
+ /* Check hash value to short circuit heavier comparison */
+ if ((hashvalue == e->h) && (h->eqfn(k, e->k)))
+ {
+ *pE = e->next;
+ h->entrycount--;
+ v = e->v;
+ freekey(e->k);
+ free(e);
+ return v;
+ }
+ pE = &(e->next);
+ e = e->next;
+ }
+ return NULL;
+}
+
+/*****************************************************************************/
+/* destroy */
+void
+hashtable_destroy(struct hashtable *h, int free_values)
+{
+ unsigned int i;
+ struct entry *e, *f;
+ struct entry **table = h->table;
+ if (free_values)
+ {
+ for (i = 0; i < h->tablelength; i++)
+ {
+ e = table[i];
+ while (NULL != e)
+ { f = e; e = e->next; freekey(f->k); free(f->v); free(f); }
+ }
+ }
+ else
+ {
+ for (i = 0; i < h->tablelength; i++)
+ {
+ e = table[i];
+ while (NULL != e)
+ { f = e; e = e->next; freekey(f->k); free(f); }
+ }
+ }
+ free(h->table);
+ free(h);
+}
+
+/*
+ * Copyright (c) 2002, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable.h b/runtime/hashtable/hashtable.h
new file mode 100644
index 00000000..b90781ab
--- /dev/null
+++ b/runtime/hashtable/hashtable.h
@@ -0,0 +1,199 @@
+/* Copyright (C) 2002 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#ifndef __HASHTABLE_CWC22_H__
+#define __HASHTABLE_CWC22_H__
+
+struct hashtable;
+
+/* Example of use:
+ *
+ * struct hashtable *h;
+ * struct some_key *k;
+ * struct some_value *v;
+ *
+ * static unsigned int hash_from_key_fn( void *k );
+ * static int keys_equal_fn ( void *key1, void *key2 );
+ *
+ * h = create_hashtable(16, hash_from_key_fn, keys_equal_fn);
+ * k = (struct some_key *) malloc(sizeof(struct some_key));
+ * v = (struct some_value *) malloc(sizeof(struct some_value));
+ *
+ * (initialise k and v to suitable values)
+ *
+ * if (! hashtable_insert(h,k,v) )
+ * { exit(-1); }
+ *
+ * if (NULL == (found = hashtable_search(h,k) ))
+ * { printf("not found!"); }
+ *
+ * if (NULL == (found = hashtable_remove(h,k) ))
+ * { printf("Not found\n"); }
+ *
+ */
+
+/* Macros may be used to define type-safe(r) hashtable access functions, with
+ * methods specialized to take known key and value types as parameters.
+ *
+ * Example:
+ *
+ * Insert this at the start of your file:
+ *
+ * DEFINE_HASHTABLE_INSERT(insert_some, struct some_key, struct some_value);
+ * DEFINE_HASHTABLE_SEARCH(search_some, struct some_key, struct some_value);
+ * DEFINE_HASHTABLE_REMOVE(remove_some, struct some_key, struct some_value);
+ *
+ * This defines the functions 'insert_some', 'search_some' and 'remove_some'.
+ * These operate just like hashtable_insert etc., with the same parameters,
+ * but their function signatures have 'struct some_key *' rather than
+ * 'void *', and hence can generate compile time errors if your program is
+ * supplying incorrect data as a key (and similarly for value).
+ *
+ * Note that the hash and key equality functions passed to create_hashtable
+ * still take 'void *' parameters instead of 'some key *'. This shouldn't be
+ * a difficult issue as they're only defined and passed once, and the other
+ * functions will ensure that only valid keys are supplied to them.
+ *
+ * The cost for this checking is increased code size and runtime overhead
+ * - if performance is important, it may be worth switching back to the
+ * unsafe methods once your program has been debugged with the safe methods.
+ * This just requires switching to some simple alternative defines - eg:
+ * #define insert_some hashtable_insert
+ *
+ */
+
+/*****************************************************************************
+ * create_hashtable
+
+ * @name create_hashtable
+ * @param minsize minimum initial size of hashtable
+ * @param hashfunction function for hashing keys
+ * @param key_eq_fn function for determining key equality
+ * @return newly created hashtable or NULL on failure
+ */
+
+struct hashtable *
+create_hashtable(unsigned int minsize,
+ unsigned int (*hashfunction) (void*),
+ int (*key_eq_fn) (void*,void*));
+
+/*****************************************************************************
+ * hashtable_insert
+
+ * @name hashtable_insert
+ * @param h the hashtable to insert into
+ * @param k the key - hashtable claims ownership and will free on removal
+ * @param v the value - does not claim ownership
+ * @return non-zero for successful insertion
+ *
+ * This function will cause the table to expand if the insertion would take
+ * the ratio of entries to table size over the maximum load factor.
+ *
+ * This function does not check for repeated insertions with a duplicate key.
+ * The value returned when using a duplicate key is undefined -- when
+ * the hashtable changes size, the order of retrieval of duplicate key
+ * entries is reversed.
+ * If in doubt, remove before insert.
+ */
+
+int
+hashtable_insert(struct hashtable *h, void *k, void *v);
+
+#define DEFINE_HASHTABLE_INSERT(fnname, keytype, valuetype) \
+int fnname (struct hashtable *h, keytype *k, valuetype *v) \
+{ \
+ return hashtable_insert(h,k,v); \
+}
+
+/*****************************************************************************
+ * hashtable_search
+
+ * @name hashtable_search
+ * @param h the hashtable to search
+ * @param k the key to search for - does not claim ownership
+ * @return the value associated with the key, or NULL if none found
+ */
+
+void *
+hashtable_search(struct hashtable *h, void *k);
+
+#define DEFINE_HASHTABLE_SEARCH(fnname, keytype, valuetype) \
+valuetype * fnname (struct hashtable *h, keytype *k) \
+{ \
+ return (valuetype *) (hashtable_search(h,k)); \
+}
+
+/*****************************************************************************
+ * hashtable_remove
+
+ * @name hashtable_remove
+ * @param h the hashtable to remove the item from
+ * @param k the key to search for - does not claim ownership
+ * @return the value associated with the key, or NULL if none found
+ */
+
+void * /* returns value */
+hashtable_remove(struct hashtable *h, void *k);
+
+#define DEFINE_HASHTABLE_REMOVE(fnname, keytype, valuetype) \
+valuetype * fnname (struct hashtable *h, keytype *k) \
+{ \
+ return (valuetype *) (hashtable_remove(h,k)); \
+}
+
+
+/*****************************************************************************
+ * hashtable_count
+
+ * @name hashtable_count
+ * @param h the hashtable
+ * @return the number of items stored in the hashtable
+ */
+unsigned int
+hashtable_count(struct hashtable *h);
+
+
+/*****************************************************************************
+ * hashtable_destroy
+
+ * @name hashtable_destroy
+ * @param h the hashtable
+ * @param free_values whether to call 'free' on the remaining values
+ */
+
+void
+hashtable_destroy(struct hashtable *h, int free_values);
+
+#endif /* __HASHTABLE_CWC22_H__ */
+
+/*
+ * Copyright (c) 2002, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable_itr.c b/runtime/hashtable/hashtable_itr.c
new file mode 100644
index 00000000..5dced841
--- /dev/null
+++ b/runtime/hashtable/hashtable_itr.c
@@ -0,0 +1,188 @@
+/* Copyright (C) 2002, 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#include "hashtable.h"
+#include "hashtable_private.h"
+#include "hashtable_itr.h"
+#include <stdlib.h> /* defines NULL */
+
+/*****************************************************************************/
+/* hashtable_iterator - iterator constructor */
+
+struct hashtable_itr *
+hashtable_iterator(struct hashtable *h)
+{
+ unsigned int i, tablelength;
+ struct hashtable_itr *itr = (struct hashtable_itr *)
+ malloc(sizeof(struct hashtable_itr));
+ if (NULL == itr) return NULL;
+ itr->h = h;
+ itr->e = NULL;
+ itr->parent = NULL;
+ tablelength = h->tablelength;
+ itr->index = tablelength;
+ if (0 == h->entrycount) return itr;
+
+ for (i = 0; i < tablelength; i++)
+ {
+ if (NULL != h->table[i])
+ {
+ itr->e = h->table[i];
+ itr->index = i;
+ break;
+ }
+ }
+ return itr;
+}
+
+/*****************************************************************************/
+/* key - return the key of the (key,value) pair at the current position */
+/* value - return the value of the (key,value) pair at the current position */
+
+void *
+hashtable_iterator_key(struct hashtable_itr *i)
+{ return i->e->k; }
+
+void *
+hashtable_iterator_value(struct hashtable_itr *i)
+{ return i->e->v; }
+
+/*****************************************************************************/
+/* advance - advance the iterator to the next element
+ * returns zero if advanced to end of table */
+
+int
+hashtable_iterator_advance(struct hashtable_itr *itr)
+{
+ unsigned int j,tablelength;
+ struct entry **table;
+ struct entry *next;
+ if (NULL == itr->e) return 0; /* stupidity check */
+
+ next = itr->e->next;
+ if (NULL != next)
+ {
+ itr->parent = itr->e;
+ itr->e = next;
+ return -1;
+ }
+ tablelength = itr->h->tablelength;
+ itr->parent = NULL;
+ if (tablelength <= (j = ++(itr->index)))
+ {
+ itr->e = NULL;
+ return 0;
+ }
+ table = itr->h->table;
+ while (NULL == (next = table[j]))
+ {
+ if (++j >= tablelength)
+ {
+ itr->index = tablelength;
+ itr->e = NULL;
+ return 0;
+ }
+ }
+ itr->index = j;
+ itr->e = next;
+ return -1;
+}
+
+/*****************************************************************************/
+/* remove - remove the entry at the current iterator position
+ * and advance the iterator, if there is a successive
+ * element.
+ * If you want the value, read it before you remove:
+ * beware memory leaks if you don't.
+ * Returns zero if end of iteration. */
+
+int
+hashtable_iterator_remove(struct hashtable_itr *itr)
+{
+ struct entry *remember_e, *remember_parent;
+ int ret;
+
+ /* Do the removal */
+ if (NULL == (itr->parent))
+ {
+ /* element is head of a chain */
+ itr->h->table[itr->index] = itr->e->next;
+ } else {
+ /* element is mid-chain */
+ itr->parent->next = itr->e->next;
+ }
+ /* itr->e is now outside the hashtable */
+ remember_e = itr->e;
+ itr->h->entrycount--;
+ freekey(remember_e->k);
+
+ /* Advance the iterator, correcting the parent */
+ remember_parent = itr->parent;
+ ret = hashtable_iterator_advance(itr);
+ if (itr->parent == remember_e) { itr->parent = remember_parent; }
+ free(remember_e);
+ return ret;
+}
+
+/*****************************************************************************/
+int /* returns zero if not found */
+hashtable_iterator_search(struct hashtable_itr *itr,
+ struct hashtable *h, void *k)
+{
+ struct entry *e, *parent;
+ unsigned int hashvalue, index;
+
+ hashvalue = hash(h,k);
+ index = indexFor(h->tablelength,hashvalue);
+
+ e = h->table[index];
+ parent = NULL;
+ while (NULL != e)
+ {
+ /* Check hash value to short circuit heavier comparison */
+ if ((hashvalue == e->h) && (h->eqfn(k, e->k)))
+ {
+ itr->index = index;
+ itr->e = e;
+ itr->parent = parent;
+ itr->h = h;
+ return -1;
+ }
+ parent = e;
+ e = e->next;
+ }
+ return 0;
+}
+
+
+/*
+ * Copyright (c) 2002, 2004, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable_itr.h b/runtime/hashtable/hashtable_itr.h
new file mode 100644
index 00000000..eea699a7
--- /dev/null
+++ b/runtime/hashtable/hashtable_itr.h
@@ -0,0 +1,112 @@
+/* Copyright (C) 2002, 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#ifndef __HASHTABLE_ITR_CWC22__
+#define __HASHTABLE_ITR_CWC22__
+#include "hashtable.h"
+#include "hashtable_private.h" /* needed to enable inlining */
+
+/*****************************************************************************/
+/* This struct is only concrete here to allow the inlining of two of the
+ * accessor functions. */
+struct hashtable_itr
+{
+ struct hashtable *h;
+ struct entry *e;
+ struct entry *parent;
+ unsigned int index;
+};
+
+
+/*****************************************************************************/
+/* hashtable_iterator
+ */
+
+struct hashtable_itr *
+hashtable_iterator(struct hashtable *h);
+
+/*****************************************************************************/
+/* hashtable_iterator_key
+ * - return the value of the (key,value) pair at the current position */
+
+extern inline void *
+hashtable_iterator_key(struct hashtable_itr *i)
+{
+ return i->e->k;
+}
+
+/*****************************************************************************/
+/* value - return the value of the (key,value) pair at the current position */
+
+extern inline void *
+hashtable_iterator_value(struct hashtable_itr *i)
+{
+ return i->e->v;
+}
+
+/*****************************************************************************/
+/* advance - advance the iterator to the next element
+ * returns zero if advanced to end of table */
+
+int
+hashtable_iterator_advance(struct hashtable_itr *itr);
+
+/*****************************************************************************/
+/* remove - remove current element and advance the iterator to the next element
+ * NB: if you need the value to free it, read it before
+ * removing. ie: beware memory leaks!
+ * returns zero if advanced to end of table */
+
+int
+hashtable_iterator_remove(struct hashtable_itr *itr);
+
+/*****************************************************************************/
+/* search - overwrite the supplied iterator, to point to the entry
+ * matching the supplied key.
+ h points to the hashtable to be searched.
+ * returns zero if not found. */
+int
+hashtable_iterator_search(struct hashtable_itr *itr,
+ struct hashtable *h, void *k);
+
+#define DEFINE_HASHTABLE_ITERATOR_SEARCH(fnname, keytype) \
+int fnname (struct hashtable_itr *i, struct hashtable *h, keytype *k) \
+{ \
+ return (hashtable_iterator_search(i,h,k)); \
+}
+
+
+
+#endif /* __HASHTABLE_ITR_CWC22__*/
+
+/*
+ * Copyright (c) 2002, 2004, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable_private.h b/runtime/hashtable/hashtable_private.h
new file mode 100644
index 00000000..3e95f600
--- /dev/null
+++ b/runtime/hashtable/hashtable_private.h
@@ -0,0 +1,85 @@
+/* Copyright (C) 2002, 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#ifndef __HASHTABLE_PRIVATE_CWC22_H__
+#define __HASHTABLE_PRIVATE_CWC22_H__
+
+#include "hashtable.h"
+
+/*****************************************************************************/
+struct entry
+{
+ void *k, *v;
+ unsigned int h;
+ struct entry *next;
+};
+
+struct hashtable {
+ unsigned int tablelength;
+ struct entry **table;
+ unsigned int entrycount;
+ unsigned int loadlimit;
+ unsigned int primeindex;
+ unsigned int (*hashfn) (void *k);
+ int (*eqfn) (void *k1, void *k2);
+};
+
+/*****************************************************************************/
+unsigned int
+hash(struct hashtable *h, void *k);
+
+/*****************************************************************************/
+/* indexFor */
+static inline unsigned int
+indexFor(unsigned int tablelength, unsigned int hashvalue) {
+ return (hashvalue % tablelength);
+};
+
+/* Only works if tablelength == 2^N */
+/*static inline unsigned int
+indexFor(unsigned int tablelength, unsigned int hashvalue)
+{
+ return (hashvalue & (tablelength - 1u));
+}
+*/
+
+/*****************************************************************************/
+#define freekey(X) free(X)
+/*define freekey(X) ; */
+
+
+/*****************************************************************************/
+
+#endif /* __HASHTABLE_PRIVATE_CWC22_H__*/
+
+/*
+ * Copyright (c) 2002, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable_utility.c b/runtime/hashtable/hashtable_utility.c
new file mode 100644
index 00000000..c3176709
--- /dev/null
+++ b/runtime/hashtable/hashtable_utility.c
@@ -0,0 +1,71 @@
+/* Copyright (C) 2002 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#include "hashtable.h"
+#include "hashtable_private.h"
+#include "hashtable_utility.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+/*****************************************************************************/
+/* hashtable_change
+ *
+ * function to change the value associated with a key, where there already
+ * exists a value bound to the key in the hashtable.
+ * Source due to Holger Schemel.
+ *
+ * */
+int
+hashtable_change(struct hashtable *h, void *k, void *v)
+{
+ struct entry *e;
+ unsigned int hashvalue, index;
+ hashvalue = hash(h,k);
+ index = indexFor(h->tablelength,hashvalue);
+ e = h->table[index];
+ while (NULL != e)
+ {
+ /* Check hash value to short circuit heavier comparison */
+ if ((hashvalue == e->h) && (h->eqfn(k, e->k)))
+ {
+ free(e->v);
+ e->v = v;
+ return -1;
+ }
+ e = e->next;
+ }
+ return 0;
+}
+
+/*
+ * Copyright (c) 2002, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/hashtable_utility.h b/runtime/hashtable/hashtable_utility.h
new file mode 100644
index 00000000..56a0ffd1
--- /dev/null
+++ b/runtime/hashtable/hashtable_utility.h
@@ -0,0 +1,55 @@
+/* Copyright (C) 2002 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#ifndef __HASHTABLE_CWC22_UTILITY_H__
+#define __HASHTABLE_CWC22_UTILITY_H__
+
+/*****************************************************************************
+ * hashtable_change
+ *
+ * function to change the value associated with a key, where there already
+ * exists a value bound to the key in the hashtable.
+ * Source due to Holger Schemel.
+ *
+ * @name hashtable_change
+ * @param h the hashtable
+ * @param key
+ * @param value
+ *
+ */
+int
+hashtable_change(struct hashtable *h, void *k, void *v);
+
+#endif /* __HASHTABLE_CWC22_H__ */
+
+/*
+ * Copyright (c) 2002, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
diff --git a/runtime/hashtable/tester.c b/runtime/hashtable/tester.c
new file mode 100644
index 00000000..4678ffa8
--- /dev/null
+++ b/runtime/hashtable/tester.c
@@ -0,0 +1,270 @@
+/* Copyright (C) 2002, 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */
+
+#include "hashtable.h"
+#include "hashtable_itr.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h> /* for memcmp */
+
+static const int ITEM_COUNT = 4000;
+
+typedef unsigned int uint32_t;
+typedef unsigned short uint16_t;
+
+/*****************************************************************************/
+struct key
+{
+ uint32_t one_ip; uint32_t two_ip; uint16_t one_port; uint16_t two_port;
+};
+
+struct value
+{
+ char *id;
+};
+
+DEFINE_HASHTABLE_INSERT(insert_some, struct key, struct value);
+DEFINE_HASHTABLE_SEARCH(search_some, struct key, struct value);
+DEFINE_HASHTABLE_REMOVE(remove_some, struct key, struct value);
+DEFINE_HASHTABLE_ITERATOR_SEARCH(search_itr_some, struct key);
+
+
+/*****************************************************************************/
+static unsigned int
+hashfromkey(void *ky)
+{
+ struct key *k = (struct key *)ky;
+ return (((k->one_ip << 17) | (k->one_ip >> 15)) ^ k->two_ip) +
+ (k->one_port * 17) + (k->two_port * 13 * 29);
+}
+
+static int
+equalkeys(void *k1, void *k2)
+{
+ return (0 == memcmp(k1,k2,sizeof(struct key)));
+}
+
+/*****************************************************************************/
+int
+main(int argc, char **argv)
+{
+ struct key *k, *kk;
+ struct value *v, *found;
+ struct hashtable *h;
+ struct hashtable_itr *itr;
+ int i;
+
+ h = create_hashtable(16, hashfromkey, equalkeys);
+ if (NULL == h) exit(-1); /*oom*/
+
+
+/*****************************************************************************/
+/* Insertion */
+ for (i = 0; i < ITEM_COUNT; i++)
+ {
+ k = (struct key *)malloc(sizeof(struct key));
+ if (NULL == k) {
+ printf("ran out of memory allocating a key\n");
+ return 1;
+ }
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ v = (struct value *)malloc(sizeof(struct value));
+ v->id = "a value";
+
+ if (!insert_some(h,k,v)) exit(-1); /*oom*/
+ }
+ printf("After insertion, hashtable contains %u items.\n",
+ hashtable_count(h));
+
+/*****************************************************************************/
+/* Hashtable search */
+ k = (struct key *)malloc(sizeof(struct key));
+ if (NULL == k) {
+ printf("ran out of memory allocating a key\n");
+ return 1;
+ }
+
+ for (i = 0; i < ITEM_COUNT; i++)
+ {
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ if (NULL == (found = search_some(h,k))) {
+ printf("BUG: key not found\n");
+ }
+ }
+
+/*****************************************************************************/
+/* Hashtable iteration */
+ /* Iterator constructor only returns a valid iterator if
+ * the hashtable is not empty */
+ itr = hashtable_iterator(h);
+ i = 0;
+ if (hashtable_count(h) > 0)
+ {
+ do {
+ kk = hashtable_iterator_key(itr);
+ v = hashtable_iterator_value(itr);
+ /* here (kk,v) are a valid (key, value) pair */
+ /* We could call 'hashtable_remove(h,kk)' - and this operation
+ * 'free's kk. However, the iterator is then broken.
+ * This is why hashtable_iterator_remove exists - see below.
+ */
+ i++;
+
+ } while (hashtable_iterator_advance(itr));
+ }
+ printf("Iterated through %u entries.\n", i);
+
+/*****************************************************************************/
+/* Hashtable iterator search */
+
+ /* Try the search some method */
+ for (i = 0; i < ITEM_COUNT; i++)
+ {
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ if (0 == search_itr_some(itr,h,k)) {
+ printf("BUG: key not found searching with iterator");
+ }
+ }
+
+/*****************************************************************************/
+/* Hashtable removal */
+
+ for (i = 0; i < ITEM_COUNT; i++)
+ {
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ if (NULL == (found = remove_some(h,k))) {
+ printf("BUG: key not found for removal\n");
+ }
+ }
+ printf("After removal, hashtable contains %u items.\n",
+ hashtable_count(h));
+
+/*****************************************************************************/
+/* Hashtable destroy and create */
+
+ hashtable_destroy(h, 1);
+ h = NULL;
+ free(k);
+
+ h = create_hashtable(160, hashfromkey, equalkeys);
+ if (NULL == h) {
+ printf("out of memory allocating second hashtable\n");
+ return 1;
+ }
+
+/*****************************************************************************/
+/* Hashtable insertion */
+
+ for (i = 0; i < ITEM_COUNT; i++)
+ {
+ k = (struct key *)malloc(sizeof(struct key));
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ v = (struct value *)malloc(sizeof(struct value));
+ v->id = "a value";
+
+ if (!insert_some(h,k,v))
+ {
+ printf("out of memory inserting into second hashtable\n");
+ return 1;
+ }
+ }
+ printf("After insertion, hashtable contains %u items.\n",
+ hashtable_count(h));
+
+/*****************************************************************************/
+/* Hashtable iterator search and iterator remove */
+
+ k = (struct key *)malloc(sizeof(struct key));
+ if (NULL == k) {
+ printf("ran out of memory allocating a key\n");
+ return 1;
+ }
+
+ for (i = ITEM_COUNT - 1; i >= 0; i = i - 7)
+ {
+ k->one_ip = 0xcfccee40 + i;
+ k->two_ip = 0xcf0cee67 - (5 * i);
+ k->one_port = 22 + (7 * i);
+ k->two_port = 5522 - (3 * i);
+
+ if (0 == search_itr_some(itr, h, k)) {
+ printf("BUG: key %u not found for search preremoval using iterator\n", i);
+ return 1;
+ }
+ if (0 == hashtable_iterator_remove(itr)) {
+ printf("BUG: key not found for removal using iterator\n");
+ return 1;
+ }
+ }
+ free(itr);
+
+/*****************************************************************************/
+/* Hashtable iterator remove and advance */
+
+ for (itr = hashtable_iterator(h);
+ hashtable_iterator_remove(itr) != 0; ) {
+ ;
+ }
+ free(itr);
+ printf("After removal, hashtable contains %u items.\n",
+ hashtable_count(h));
+
+/*****************************************************************************/
+/* Hashtable destroy */
+
+ hashtable_destroy(h, 1);
+ free(k);
+ return 0;
+}
+
+/*
+ * Copyright (c) 2002, 2004, Christopher Clark
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of the original author; nor the names of any contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/