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-rw-r--r--python/sip/siplib/objmap.c264
1 files changed, 0 insertions, 264 deletions
diff --git a/python/sip/siplib/objmap.c b/python/sip/siplib/objmap.c
deleted file mode 100644
index efc7bc2a..00000000
--- a/python/sip/siplib/objmap.c
+++ /dev/null
@@ -1,264 +0,0 @@
-/*
- * This module implements a hash table class for mapping C/C++ addresses to the
- * corresponding wrapped Python object.
- *
- * Copyright (c) 2007
- * Riverbank Computing Limited <info@riverbankcomputing.co.uk>
- *
- * This file is part of SIP.
- *
- * This copy of SIP is licensed for use under the terms of the SIP License
- * Agreement. See the file LICENSE for more details.
- *
- * SIP is supplied WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- */
-
-
-#include <string.h>
-
-#include "sip.h"
-#include "sipint.h"
-
-
-#define hash_1(k,s) (((unsigned long)(k)) % (s))
-#define hash_2(k,s) ((s) - 2 - (hash_1((k),(s)) % ((s) - 2)))
-
-
-/* Prime numbers to use as hash table sizes. */
-static unsigned long hash_primes[] = {
- 521, 1031, 2053, 4099,
- 8209, 16411, 32771, 65537, 131101, 262147,
- 524309, 1048583, 2097169, 4194319, 8388617, 16777259,
- 33554467, 67108879, 134217757, 268435459, 536870923, 1073741827,
- 2147483659U,0
-};
-
-
-static sipHashEntry *newHashTable(unsigned long);
-static sipHashEntry *findHashEntry(sipObjectMap *,void *);
-static void reorganiseMap(sipObjectMap *om);
-
-
-/*
- * Initialise an object map.
- */
-void sipOMInit(sipObjectMap *om)
-{
- om -> primeIdx = 0;
- om -> unused = om -> size = hash_primes[om -> primeIdx];
- om -> stale = 0;
- om -> hash_array = newHashTable(om -> size);
-}
-
-
-/*
- * Finalise an object map.
- */
-void sipOMFinalise(sipObjectMap *om)
-{
- sip_api_free(om -> hash_array);
-}
-
-
-/*
- * Allocate and initialise a new hash table.
- */
-static sipHashEntry *newHashTable(unsigned long size)
-{
- size_t nbytes;
- sipHashEntry *hashtab;
-
- nbytes = sizeof (sipHashEntry) * size;
-
- if ((hashtab = (sipHashEntry *)sip_api_malloc(nbytes)) != NULL)
- memset(hashtab,0,nbytes);
-
- return hashtab;
-}
-
-
-/*
- * Return a pointer to the hash entry that is used, or should be used, for the
- * given C/C++ address.
- */
-static sipHashEntry *findHashEntry(sipObjectMap *om,void *key)
-{
- unsigned long hash, inc;
- void *hek;
-
- hash = hash_1(key,om -> size);
- inc = hash_2(key,om -> size);
-
- while ((hek = om -> hash_array[hash].key) != NULL && hek != key)
- hash = (hash + inc) % om -> size;
-
- return &om -> hash_array[hash];
-}
-
-
-/*
- * Return the wrapped Python object of a specific type for a C/C++ address or
- * NULL if it wasn't found.
- */
-sipWrapper *sipOMFindObject(sipObjectMap *om,void *key, sipWrapperType *type)
-{
- sipHashEntry *he = findHashEntry(om, key);
- sipWrapper *w;
-
- /* Go through each wrapped object at this address. */
- for (w = he->first; w != NULL; w = w->next)
- {
- /*
- * If this wrapped object is of the given type, or a sub-type
- * of it, or vice versa, then we assume it is the same C++
- * object.
- */
- if (PyObject_TypeCheck(w, (PyTypeObject *)type) ||
- PyType_IsSubtype((PyTypeObject *)type, w->ob_type))
- return w;
- }
-
- return NULL;
-}
-
-
-/*
- * Add a C/C++ address and the corresponding wrapped Python object to the map.
- */
-void sipOMAddObject(sipObjectMap *om,sipWrapper *val)
-{
- sipHashEntry *he = findHashEntry(om,val -> u.cppPtr);
-
- /*
- * If the bucket is in use then we appear to have several objects at
- * the same address.
- */
- if (he -> first != NULL)
- {
- /*
- * This can happen for three reasons. A variable of one class
- * can be declared at the start of another class. Therefore
- * there are two objects, of different classes, with the same
- * address. The second reason is that the old C/C++ object has
- * been deleted by C/C++ but we didn't get to find out for some
- * reason, and a new C/C++ instance has been created at the
- * same address. The third reason is if we are in the process
- * of deleting a Python object but the C++ object gets wrapped
- * again because the C++ dtor called a method that has been
- * re-implemented in Python. The absence of the SIP_SHARE_MAP
- * flag tells us that a new C++ instance has just been created
- * and so we know the second reason is the correct one so we
- * mark the old pointers as invalid and reuse the entry.
- * Otherwise we just add this one to the existing list of
- * objects at this address.
- */
- if (!(val -> flags & SIP_SHARE_MAP))
- {
- sipWrapper *w;
-
- for (w = he -> first; w != NULL; w = w -> next)
- w -> u.cppPtr = NULL;
-
- he -> first = NULL;
- }
-
- val -> next = he -> first;
- he -> first = val;
-
- return;
- }
-
- /* See if the bucket was unused or stale. */
- if (he -> key == NULL)
- {
- he -> key = val -> u.cppPtr;
- om -> unused--;
- }
- else
- om -> stale--;
-
- /* Add the rest of the new value. */
- he -> first = val;
- val -> next = NULL;
-
- reorganiseMap(om);
-}
-
-
-/*
- * Reorganise a map if it is running short of space.
- */
-static void reorganiseMap(sipObjectMap *om)
-{
- unsigned long old_size, i;
- sipHashEntry *ohe, *old_tab;
-
- /* Don't bother if it still has more than 12% available. */
- if (om -> unused > om -> size >> 3)
- return;
-
- /*
- * If reorganising (ie. making the stale buckets unused) using the same
- * sized table would make 25% available then do that. Otherwise use a
- * bigger table (if possible).
- */
- if (om -> unused + om -> stale < om -> size >> 2 && hash_primes[om -> primeIdx + 1] != 0)
- om -> primeIdx++;
-
- old_size = om -> size;
- old_tab = om -> hash_array;
-
- om -> unused = om -> size = hash_primes[om -> primeIdx];
- om -> stale = 0;
- om -> hash_array = newHashTable(om -> size);
-
- /* Transfer the entries from the old table to the new one. */
- ohe = old_tab;
-
- for (i = 0; i < old_size; ++i)
- {
- if (ohe -> key != NULL && ohe -> first != NULL)
- {
- *findHashEntry(om,ohe -> key) = *ohe;
- om -> unused--;
- }
-
- ++ohe;
- }
-
- sip_api_free(old_tab);
-}
-
-
-/*
- * Remove a C/C++ object from the table. Return 0 if it was removed
- * successfully.
- */
-int sipOMRemoveObject(sipObjectMap *om,sipWrapper *val)
-{
- sipHashEntry *he = findHashEntry(om,val -> u.cppPtr);
- sipWrapper **wp;
-
- for (wp = &he -> first; *wp != NULL; wp = &(*wp) -> next)
- if (*wp == val)
- {
- *wp = val -> next;
-
- /*
- * If the bucket is now empty then count it as stale.
- * Note that we do not NULL the key and count it as
- * unused because that might throw out the search for
- * another entry that wanted to go here, found it
- * already occupied, and was put somewhere else. In
- * other words, searches must be repeatable until we
- * reorganise the table.
- */
- if (he -> first == NULL)
- om -> stale++;
-
- return 0;
- }
-
- return -1;
-}
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