VypressChat added (not adopted)

git-svn-id: http://svn.miranda-ng.org/main/trunk@4285 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 287 insertions, 0 deletions

diff --git a/plugins/!NotAdopted/VypressChat/contrib/hashtable.c b/plugins/!NotAdopted/VypressChat/contrib/hashtable.c
new file mode 100644
index 0000000000..5bc1b2f539
--- /dev/null
+++ b/plugins/!NotAdopted/VypressChat/contrib/hashtable.c
@@ -0,0 +1,287 @@
+/* Copyright (C) 2004 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */

+

+#include "hashtable.h"

+#include "hashtable_private.h"

+#include <stdlib.h>

+#include <stdio.h>

+#include <string.h>

+#include <math.h>

+

+#ifdef MEMWATCH

+# include "../contrib/memwatch.h"

+#endif

+

+/*

+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*),

+		 void (*value_free_fn)(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->value_free_fn = value_free_fn;

+    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, index;

+    /* 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;

+                index = indexFor(newsize,e->h);

+                e->next = newtable[index];

+                newtable[index] = 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) {

+                index = indexFor(newsize,e->h);

+                if (index == i)

+                {

+                    pE = &(e->next);

+                }

+                else

+                {

+                    *pE = e->next;

+                    e->next = newtable[index];

+                    newtable[index] = 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 index;

+    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);

+    index = indexFor(h->tablelength,e->h);

+    e->k = k;

+    e->v = v;

+    e->next = h->table[index];

+    h->table[index] = e;

+    return -1;

+}

+

+/*****************************************************************************/

+void * /* returns value associated with key */

+hashtable_search(struct hashtable *h, void *k)

+{

+    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))) return e->v;

+        e = e->next;

+    }

+    return NULL;

+}

+

+/*****************************************************************************/

+void * /* returns value associated with key */

+hashtable_remove(struct hashtable *h, void *k, int free_value)

+{

+    /* 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, index;

+

+    hashvalue = hash(h,k);

+    index = indexFor(h->tablelength,hash(h,k));

+    pE = &(h->table[index]);

+    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);

+

+            if(h->value_free_fn && free_value) {

+                h->value_free_fn(v);

+		v = NULL;

+            }

+

+            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);

+              if(h->value_free_fn) h->value_free_fn(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);

+}

+

+void hashtable_enumerate(

+	struct hashtable * h,

+	hashtable_enum_fn enum_fn, void * user_data)

+{

+	unsigned int i;

+	struct entry * e;

+

+	for(i = 0; i < h->tablelength; i++) {

+		for(e = h->table[i]; e; e = e->next)

+			if(!enum_fn(e->k, e->v, user_data))

+				return;

+	}

+}

+

+/*

+ * Copyright (C) 2002 Christopher Clark <firstname.lastname@cl.cam.ac.uk>

+ *

+ * Permission is hereby granted, free of charge, to any person obtaining a copy

+ * of this software and associated documentation files (the "Software"), to

+ * deal in the Software without restriction, including without limitation the

+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

+ * sell copies of the Software, and to permit persons to whom the Software is

+ * furnished to do so, subject to the following conditions:

+ *

+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

+ * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER

+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

+ * */