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+/* Ordered Dictionary object implementation.
+
+This implementation is necessarily explicitly equivalent to the pure Python
+OrderedDict class in Lib/collections/__init__.py. The strategy there
+involves using a doubly-linked-list to capture the order. We keep to that
+strategy, using a lower-level linked-list.
+
+About the Linked-List
+=====================
+
+For the linked list we use a basic doubly-linked-list. Using a circularly-
+linked-list does have some benefits, but they don't apply so much here
+since OrderedDict is focused on the ends of the list (for the most part).
+Furthermore, there are some features of generic linked-lists that we simply
+don't need for OrderedDict. Thus a simple custom implementation meets our
+needs. Alternatives to our simple approach include the QCIRCLE_*
+macros from BSD's queue.h, and the linux's list.h.
+
+Getting O(1) Node Lookup
+------------------------
+
+One invariant of Python's OrderedDict is that it preserves time complexity
+of dict's methods, particularly the O(1) operations. Simply adding a
+linked-list on top of dict is not sufficient here; operations for nodes in
+the middle of the linked-list implicitly require finding the node first.
+With a simple linked-list like we're using, that is an O(n) operation.
+Consequently, methods like __delitem__() would change from O(1) to O(n),
+which is unacceptable.
+
+In order to preserve O(1) performance for node removal (finding nodes), we
+must do better than just looping through the linked-list. Here are options
+we've considered:
+
+1. use a second dict to map keys to nodes (a la the pure Python version).
+2. keep a simple hash table mirroring the order of dict's, mapping each key
+ to the corresponding node in the linked-list.
+3. use a version of shared keys (split dict) that allows non-unicode keys.
+4. have the value stored for each key be a (value, node) pair, and adjust
+ __getitem__(), get(), etc. accordingly.
+
+The approach with the least performance impact (time and space) is #2,
+mirroring the key order of dict's dk_enties with an array of node pointers.
+While lookdict() and friends (dk_lookup) don't give us the index into the
+array, we make use of pointer arithmetic to get that index. An alternative
+would be to refactor lookdict() to provide the index, explicitly exposing
+the implementation detail. We could even just use a custom lookup function
+for OrderedDict that facilitates our need. However, both approaches are
+significantly more complicated than just using pointer arithmetic.
+
+The catch with mirroring the hash table ordering is that we have to keep
+the ordering in sync through any dict resizes. However, that order only
+matters during node lookup. We can simply defer any potential resizing
+until we need to do a lookup.
+
+Linked-List Nodes
+-----------------
+
+The current implementation stores a pointer to the associated key only.
+One alternative would be to store a pointer to the PyDictKeyEntry instead.
+This would save one pointer de-reference per item, which is nice during
+calls to values() and items(). However, it adds unnecessary overhead
+otherwise, so we stick with just the key.
+
+Linked-List API
+---------------
+
+As noted, the linked-list implemented here does not have all the bells and
+whistles. However, we recognize that the implementation may need to
+change to accommodate performance improvements or extra functionality. To
+that end, We use a simple API to interact with the linked-list. Here's a
+summary of the methods/macros:
+
+Node info:
+
+* _odictnode_KEY(node)
+* _odictnode_VALUE(od, node)
+* _odictnode_PREV(node)
+* _odictnode_NEXT(node)
+
+Linked-List info:
+
+* _odict_FIRST(od)
+* _odict_LAST(od)
+* _odict_EMPTY(od)
+* _odict_FOREACH(od, node) - used in place of `for (node=...)`
+
+For adding nodes:
+
+* _odict_add_head(od, node)
+* _odict_add_tail(od, node)
+* _odict_add_new_node(od, key)
+
+For removing nodes:
+
+* _odict_pop_node(od, node, key)
+* _odict_clear_node(od, node)
+* _odict_clear_nodes(od, clear_each)
+
+Others:
+
+* _odict_initialize(od)
+* _odict_find_node(od, key)
+* _odict_keys_equal(od1, od2)
+
+Used, but specific to the linked-list implementation:
+
+* _odict_free_fast_nodes(od)
+
+And here's a look at how the linked-list relates to the OrderedDict API:
+
+============ === === ==== ==== ==== === ==== ===== ==== ==== === ==== === ===
+method key val prev next mem 1st last empty iter find add rmv clr keq
+============ === === ==== ==== ==== === ==== ===== ==== ==== === ==== === ===
+__del__ ~ X
+__delitem__ free ~ node
+__eq__ ~ X
+__iter__ X X
+__new__ X X
+__reduce__ X ~ X
+__repr__ X X X
+__reversed__ X X
+__setitem__ key
+__sizeof__ size X
+clear ~ ~ X
+copy X X X
+items X X X
+keys X X
+move_to_end X X X ~ h/t key
+pop free key
+popitem X X free X X node
+setdefault ~ ? ~
+values X X
+============ === === ==== ==== ==== === ==== ===== ==== ==== === ==== === ===
+
+__delitem__ is the only method that directly relies on finding an arbitrary
+node in the linked-list. Everything else is iteration or relates to the
+ends of the linked-list.
+
+Situation that Endangers Consistency
+------------------------------------
+Using a raw linked-list for OrderedDict exposes a key situation that can
+cause problems. If a node is stored in a variable, there is a chance that
+the node may have been deallocated before the variable gets used, thus
+potentially leading to a segmentation fault. A key place where this shows
+up is during iteration through the linked list (via _odict_FOREACH or
+otherwise).
+
+A number of solutions are available to resolve this situation:
+
+* defer looking up the node until as late as possible and certainly after
+ any code that could possibly result in a deletion;
+* if the node is needed both before and after a point where the node might
+ be removed, do a check before using the node at the "after" location to
+ see if the node is still valid;
+* like the last one, but simply pull the node again to ensure it's right;
+* keep the key in the variable instead of the node and then look up the
+ node using the key at the point where the node is needed (this is what
+ we do for the iterators).
+
+Another related problem, preserving consistent ordering during iteration,
+is described below. That one is not exclusive to using linked-lists.
+
+
+Challenges from Subclassing dict
+================================
+
+OrderedDict subclasses dict, which is an unusual relationship between two
+builtin types (other than the base object type). Doing so results in
+some complication and deserves further explanation. There are two things
+to consider here. First, in what circumstances or with what adjustments
+can OrderedDict be used as a drop-in replacement for dict (at the C level)?
+Second, how can the OrderedDict implementation leverage the dict
+implementation effectively without introducing unnecessary coupling or
+inefficiencies?
+
+This second point is reflected here and in the implementation, so the
+further focus is on the first point. It is worth noting that for
+overridden methods, the dict implementation is deferred to as much as
+possible. Furthermore, coupling is limited to as little as is reasonable.
+
+Concrete API Compatibility
+--------------------------
+
+Use of the concrete C-API for dict (PyDict_*) with OrderedDict is
+problematic. (See http://bugs.python.org/issue10977.) The concrete API
+has a number of hard-coded assumptions tied to the dict implementation.
+This is, in part, due to performance reasons, which is understandable
+given the part dict plays in Python.
+
+Any attempt to replace dict with OrderedDict for any role in the
+interpreter (e.g. **kwds) faces a challenge. Such any effort must
+recognize that the instances in affected locations currently interact with
+the concrete API.
+
+Here are some ways to address this challenge:
+
+1. Change the relevant usage of the concrete API in CPython and add
+ PyDict_CheckExact() calls to each of the concrete API funcions.
+2. Adjust the relevant concrete API functions to explicitly accommodate
+ OrderedDict.
+3. As with #1, add the checks, but improve the abstract API with smart fast
+ paths for dict and OrderedDict, and refactor CPython to use the abstract
+ API. Improvements to the abstract API would be valuable regardless.
+
+Adding the checks to the concrete API would help make any interpreter
+switch to OrderedDict less painful for extension modules. However, this
+won't work. The equivalent C API call to `dict.__setitem__(obj, k, v)`
+is 'PyDict_SetItem(obj, k, v)`. This illustrates how subclasses in C call
+the base class's methods, since there is no equivalent of super() in the
+C API. Calling into Python for parent class API would work, but some
+extension modules already rely on this feature of the concrete API.
+
+For reference, here is a breakdown of some of the dict concrete API:
+
+========================== ============= =======================
+concrete API uses abstract API
+========================== ============= =======================
+PyDict_Check PyMapping_Check
+(PyDict_CheckExact) -
+(PyDict_New) -
+(PyDictProxy_New) -
+PyDict_Clear -
+PyDict_Contains PySequence_Contains
+PyDict_Copy -
+PyDict_SetItem PyObject_SetItem
+PyDict_SetItemString PyMapping_SetItemString
+PyDict_DelItem PyMapping_DelItem
+PyDict_DelItemString PyMapping_DelItemString
+PyDict_GetItem -
+PyDict_GetItemWithError PyObject_GetItem
+_PyDict_GetItemIdWithError -
+PyDict_GetItemString PyMapping_GetItemString
+PyDict_Items PyMapping_Items
+PyDict_Keys PyMapping_Keys
+PyDict_Values PyMapping_Values
+PyDict_Size PyMapping_Size
+ PyMapping_Length
+PyDict_Next PyIter_Next
+_PyDict_Next -
+PyDict_Merge -
+PyDict_Update -
+PyDict_MergeFromSeq2 -
+PyDict_ClearFreeList -
+- PyMapping_HasKeyString
+- PyMapping_HasKey
+========================== ============= =======================
+
+
+The dict Interface Relative to OrderedDict
+==========================================
+
+Since OrderedDict subclasses dict, understanding the various methods and
+attributes of dict is important for implementing OrderedDict.
+
+Relevant Type Slots
+-------------------
+
+================= ================ =================== ================
+slot attribute object dict
+================= ================ =================== ================
+tp_dealloc - object_dealloc dict_dealloc
+tp_repr __repr__ object_repr dict_repr
+sq_contains __contains__ - dict_contains
+mp_length __len__ - dict_length
+mp_subscript __getitem__ - dict_subscript
+mp_ass_subscript __setitem__ - dict_ass_sub
+ __delitem__
+tp_hash __hash__ _Py_HashPointer ..._HashNotImpl
+tp_str __str__ object_str -
+tp_getattro __getattribute__ ..._GenericGetAttr (repeated)
+ __getattr__
+tp_setattro __setattr__ ..._GenericSetAttr (disabled)
+tp_doc __doc__ (literal) dictionary_doc
+tp_traverse - - dict_traverse
+tp_clear - - dict_tp_clear
+tp_richcompare __eq__ object_richcompare dict_richcompare
+ __ne__
+tp_weaklistoffset (__weakref__) - -
+tp_iter __iter__ - dict_iter
+tp_dictoffset (__dict__) - -
+tp_init __init__ object_init dict_init
+tp_alloc - PyType_GenericAlloc (repeated)
+tp_new __new__ object_new dict_new
+tp_free - PyObject_Del PyObject_GC_Del
+================= ================ =================== ================
+
+Relevant Methods
+----------------
+
+================ =================== ===============
+method object dict
+================ =================== ===============
+__reduce__ object_reduce -
+__sizeof__ object_sizeof dict_sizeof
+clear - dict_clear
+copy - dict_copy
+fromkeys - dict_fromkeys
+get - dict_get
+items - dictitems_new
+keys - dictkeys_new
+pop - dict_pop
+popitem - dict_popitem
+setdefault - dict_setdefault
+update - dict_update
+values - dictvalues_new
+================ =================== ===============
+
+
+Pure Python OrderedDict
+=======================
+
+As already noted, compatibility with the pure Python OrderedDict
+implementation is a key goal of this C implementation. To further that
+goal, here's a summary of how OrderedDict-specific methods are implemented
+in collections/__init__.py. Also provided is an indication of which
+methods directly mutate or iterate the object, as well as any relationship
+with the underlying linked-list.
+
+============= ============== == ================ === === ====
+method impl used ll uses inq mut iter
+============= ============== == ================ === === ====
+__contains__ dict - - X
+__delitem__ OrderedDict Y dict.__delitem__ X
+__eq__ OrderedDict N OrderedDict ~
+ dict.__eq__
+ __iter__
+__getitem__ dict - - X
+__iter__ OrderedDict Y - X
+__init__ OrderedDict N update
+__len__ dict - - X
+__ne__ MutableMapping - __eq__ ~
+__reduce__ OrderedDict N OrderedDict ~
+ __iter__
+ __getitem__
+__repr__ OrderedDict N __class__ ~
+ items
+__reversed__ OrderedDict Y - X
+__setitem__ OrderedDict Y __contains__ X
+ dict.__setitem__
+__sizeof__ OrderedDict Y __len__ ~
+ __dict__
+clear OrderedDict Y dict.clear X
+copy OrderedDict N __class__
+ __init__
+fromkeys OrderedDict N __setitem__
+get dict - - ~
+items MutableMapping - ItemsView X
+keys MutableMapping - KeysView X
+move_to_end OrderedDict Y - X
+pop OrderedDict N __contains__ X
+ __getitem__
+ __delitem__
+popitem OrderedDict Y dict.pop X
+setdefault OrderedDict N __contains__ ~
+ __getitem__
+ __setitem__
+update MutableMapping - __setitem__ ~
+values MutableMapping - ValuesView X
+============= ============== == ================ === === ====
+
+__reversed__ and move_to_end are both exclusive to OrderedDict.
+
+
+C OrderedDict Implementation
+============================
+
+================= ================
+slot impl
+================= ================
+tp_dealloc odict_dealloc
+tp_repr odict_repr
+mp_ass_subscript odict_ass_sub
+tp_doc odict_doc
+tp_traverse odict_traverse
+tp_clear odict_tp_clear
+tp_richcompare odict_richcompare
+tp_weaklistoffset (offset)
+tp_iter odict_iter
+tp_dictoffset (offset)
+tp_init odict_init
+tp_alloc (repeated)
+tp_new odict_new
+================= ================
+
+================= ================
+method impl
+================= ================
+__reduce__ odict_reduce
+__sizeof__ odict_sizeof
+clear odict_clear
+copy odict_copy
+fromkeys odict_fromkeys
+items odictitems_new
+keys odictkeys_new
+pop odict_pop
+popitem odict_popitem
+setdefault odict_setdefault
+update odict_update
+values odictvalues_new
+================= ================
+
+Inherited unchanged from object/dict:
+
+================ ==========================
+method type field
+================ ==========================
+- tp_free
+__contains__ tp_as_sequence.sq_contains
+__getattr__ tp_getattro
+__getattribute__ tp_getattro
+__getitem__ tp_as_mapping.mp_subscript
+__hash__ tp_hash
+__len__ tp_as_mapping.mp_length
+__setattr__ tp_setattro
+__str__ tp_str
+get -
+================ ==========================
+
+
+Other Challenges
+================
+
+Preserving Ordering During Iteration
+------------------------------------
+During iteration through an OrderedDict, it is possible that items could
+get added, removed, or reordered. For a linked-list implementation, as
+with some other implementations, that situation may lead to undefined
+behavior. The documentation for dict mentions this in the `iter()` section
+of http://docs.python.org/3.4/library/stdtypes.html#dictionary-view-objects.
+In this implementation we follow dict's lead (as does the pure Python
+implementation) for __iter__(), keys(), values(), and items().
+
+For internal iteration (using _odict_FOREACH or not), there is still the
+risk that not all nodes that we expect to be seen in the loop actually get
+seen. Thus, we are careful in each of those places to ensure that they
+are. This comes, of course, at a small price at each location. The
+solutions are much the same as those detailed in the `Situation that
+Endangers Consistency` section above.
+
+
+Potential Optimizations
+=======================
+
+* Allocate the nodes as a block via od_fast_nodes instead of individually.
+ - Set node->key to NULL to indicate the node is not-in-use.
+ - Add _odict_EXISTS()?
+ - How to maintain consistency across resizes? Existing node pointers
+ would be invalidate after a resize, which is particularly problematic
+ for the iterators.
+* Use a more stream-lined implementation of update() and, likely indirectly,
+ __init__().
+
+*/
+
+/* TODO
+
+sooner:
+- reentrancy (make sure everything is at a thread-safe state when calling
+ into Python). I've already checked this multiple times, but want to
+ make one more pass.
+- add unit tests for reentrancy?
+
+later:
+- make the dict views support the full set API (the pure Python impl does)
+- implement a fuller MutableMapping API in C?
+- move the MutableMapping implementation to abstract.c?
+- optimize mutablemapping_update
+- use PyObject_MALLOC (small object allocator) for odict nodes?
+- support subclasses better (e.g. in odict_richcompare)
+
+*/
+
+#include "Python.h"
+#include "structmember.h"
+#include "dict-common.h"
+#include <stddef.h>
+
+
+typedef struct _odictnode _ODictNode;
+
+/* PyODictObject */
+struct _odictobject {
+ /* od_dict is the underlying dict. */
+ PyDictObject od_dict;
+ /* od_first is the first node in the odict, if any. */
+ _ODictNode *od_first;
+ /* od_last is the last node in the odict, if any. */
+ _ODictNode *od_last;
+ /* od_size is the number of entries in od_fast_nodes. */
+ Py_ssize_t od_size; /* managed by _odict_resize() */
+ /* od_fast_nodes is a hash table that mirrors the dict table. */
+ _ODictNode **od_fast_nodes; /* managed by _odict_resize() */
+ /* od_inst_dict is OrderedDict().__dict__. */
+ PyObject *od_inst_dict;
+ /* od_weakreflist holds weakrefs to the odict. */
+ PyObject *od_weakreflist;
+};
+
+
+/* ----------------------------------------------
+ * odict keys (a simple doubly-linked list)
+ */
+
+struct _odictnode {
+ PyObject *key;
+ _ODictNode *next;
+ _ODictNode *prev;
+};
+
+#define _odictnode_KEY(node) \
+ (node->key)
+/* borrowed reference */
+#define _odictnode_VALUE(node, od) \
+ PyODict_GetItem((PyObject *)od, _odictnode_KEY(node))
+/* If needed we could also have _odictnode_HASH. */
+#define _odictnode_PREV(node) (node->prev)
+#define _odictnode_NEXT(node) (node->next)
+
+#define _odict_FIRST(od) (((PyODictObject *)od)->od_first)
+#define _odict_LAST(od) (((PyODictObject *)od)->od_last)
+#define _odict_EMPTY(od) (_odict_FIRST(od) == NULL)
+#define _odict_FOREACH(od, node) \
+ for (node = _odict_FIRST(od); node != NULL; node = _odictnode_NEXT(node))
+
+
+static Py_ssize_t _odict_get_index(PyODictObject *, PyObject *); /* forward */
+
+static void
+_odict_free_fast_nodes(PyODictObject *od) {
+ if (od->od_fast_nodes) {
+ PyMem_FREE(od->od_fast_nodes);
+ }
+}
+
+static int
+_odict_resize(PyODictObject *od) {
+ Py_ssize_t size, prev_size, i;
+ _ODictNode **fast_nodes, *node;
+
+ /* Initialize a new "fast nodes" table. */
+ size = ((PyDictObject *)od)->ma_keys->dk_size;
+ fast_nodes = PyMem_NEW(_ODictNode *, size);
+ if (fast_nodes == NULL) {
+ PyErr_NoMemory();
+ return -1;
+ }
+ for (i = 0; i < size; i++)
+ fast_nodes[i] = NULL;
+
+ /* Copy the current nodes into the table. */
+ prev_size = od->od_size;
+ od->od_size = size;
+ _odict_FOREACH(od, node) {
+ assert(node != NULL);
+ i = _odict_get_index(od, _odictnode_KEY(node));
+ if (i < 0) {
+ od->od_size = prev_size;
+ PyMem_FREE(fast_nodes);
+ return -1;
+ }
+ fast_nodes[i] = node;
+ }
+ if (size != ((PyDictObject *)od)->ma_keys->dk_size) {
+ /* If _odict_get_index triggered a resize then we are already done. */
+ PyMem_FREE(fast_nodes);
+ return 0;
+ }
+
+ /* Replace the old fast nodes table. */
+ _odict_free_fast_nodes(od);
+ od->od_fast_nodes = fast_nodes;
+ return 0;
+}
+
+/* Return the index into the hash table, regardless of a valid node. */
+static Py_ssize_t
+_odict_get_index(PyODictObject *od, PyObject *key)
+{
+ Py_hash_t hash;
+ PyObject **value_addr = NULL;
+ PyDictKeyEntry *ep;
+ PyDictKeysObject *keys = ((PyDictObject *)od)->ma_keys;
+
+ assert(key != NULL);
+ do {
+ /* Ensure od_fast_nodes and dk_entries are in sync. */
+ if (keys->dk_size != od->od_size) {
+ int resize_res = _odict_resize(od);
+ if (resize_res < 0)
+ return -1;
+ }
+
+ /* now get the index */
+ hash = PyObject_Hash(key);
+ if (hash == -1)
+ return -1;
+ /* May have resized during the PyObject_Hash() call. */
+ keys = ((PyDictObject *)od)->ma_keys;
+ } while (keys->dk_size != od->od_size);
+
+ ep = (keys->dk_lookup)((PyDictObject *)od, key, hash, &value_addr);
+ if (ep == NULL)
+ return -1;
+ /* We use pointer arithmetic to get the entry's index into the table. */
+ return ep - keys->dk_entries;
+}
+
+static int
+_odict_initialize(PyODictObject *od)
+{
+ _odict_FIRST(od) = NULL;
+ _odict_LAST(od) = NULL;
+ return _odict_resize((PyODictObject *)od);
+}
+
+/* Returns NULL if there was some error or the key was not found. */
+static _ODictNode *
+_odict_find_node(PyODictObject *od, PyObject *key)
+{
+ Py_ssize_t index;
+
+ if (_odict_EMPTY(od))
+ return NULL;
+ index = _odict_get_index(od, key);
+ if (index < 0)
+ return NULL;
+ return od->od_fast_nodes[index];
+}
+
+static void
+_odict_add_head(PyODictObject *od, _ODictNode *node)
+{
+ if (_odict_FIRST(od) == NULL) {
+ _odictnode_PREV(node) = NULL;
+ _odictnode_NEXT(node) = NULL;
+ _odict_FIRST(od) = node;
+ _odict_LAST(od) = node;
+ }
+ else {
+ _odictnode_PREV(node) = NULL;
+ _odictnode_NEXT(node) = _odict_FIRST(od);
+ _odict_FIRST(od) = node;
+ _odictnode_PREV(_odict_FIRST(od)) = node;
+ }
+}
+
+static void
+_odict_add_tail(PyODictObject *od, _ODictNode *node)
+{
+ if (_odict_LAST(od) == NULL) {
+ _odictnode_PREV(node) = NULL;
+ _odictnode_NEXT(node) = NULL;
+ _odict_FIRST(od) = node;
+ _odict_LAST(od) = node;
+ }
+ else {
+ _odictnode_PREV(node) = _odict_LAST(od);
+ _odictnode_NEXT(node) = NULL;
+ _odictnode_NEXT(_odict_LAST(od)) = node;
+ _odict_LAST(od) = node;
+ }
+}
+
+/* adds the node to the end of the list */
+static int
+_odict_add_new_node(PyODictObject *od, PyObject *key)
+{
+ Py_ssize_t i;
+ _ODictNode *node;
+
+ Py_INCREF(key);
+ i = _odict_get_index(od, key);
+ if (i < 0) {
+ if (!PyErr_Occurred())
+ PyErr_SetObject(PyExc_KeyError, key);
+ Py_DECREF(key);
+ return -1;
+ }
+ else if (od->od_fast_nodes[i] != NULL) {
+ /* We already have a node for the key so there's no need to add one. */
+ Py_DECREF(key);
+ return 0;
+ }
+
+ /* must not be added yet */
+ node = (_ODictNode *)PyMem_MALLOC(sizeof(_ODictNode));
+ if (node == NULL) {
+ Py_DECREF(key);
+ PyErr_NoMemory();
+ return -1;
+ }
+
+ _odictnode_KEY(node) = key;
+ _odict_add_tail(od, node);
+ od->od_fast_nodes[i] = node;
+ return 0;
+}
+
+/* Putting the decref after the free causes problems. */
+#define _odictnode_DEALLOC(node) \
+ do { \
+ Py_DECREF(_odictnode_KEY(node)); \
+ PyMem_FREE((void *)node); \
+ } while (0)
+
+/* Repeated calls on the same node are no-ops. */
+static void
+_odict_remove_node(PyODictObject *od, _ODictNode *node)
+{
+ if (_odict_FIRST(od) == node)
+ _odict_FIRST(od) = _odictnode_NEXT(node);
+ else if (_odictnode_PREV(node) != NULL)
+ _odictnode_NEXT(_odictnode_PREV(node)) = _odictnode_NEXT(node);
+
+ if (_odict_LAST(od) == node)
+ _odict_LAST(od) = _odictnode_PREV(node);
+ else if (_odictnode_NEXT(node) != NULL)
+ _odictnode_PREV(_odictnode_NEXT(node)) = _odictnode_PREV(node);
+
+ _odictnode_PREV(node) = NULL;
+ _odictnode_NEXT(node) = NULL;
+}
+
+static _ODictNode *
+_odict_pop_node(PyODictObject *od, _ODictNode *node, PyObject *key)
+{
+ if (node == NULL) {
+ node = _odict_find_node(od, key);
+ if (node == NULL)
+ return NULL;
+ }
+ _odict_remove_node(od, node);
+ return node;
+}
+
+/* If someone calls PyDict_DelItem() directly on an OrderedDict, we'll
+ get all sorts of problems here. In PyODict_DelItem we make sure to
+ call _odict_clear_node first.
+
+ This matters in the case of colliding keys. Suppose we add 3 keys:
+ [A, B, C], where the hash of C collides with A and the next possible
+ index in the hash table is occupied by B. If we remove B then for C
+ the dict's looknode func will give us the old index of B instead of
+ the index we got before deleting B. However, the node for C in
+ od_fast_nodes is still at the old dict index of C. Thus to be sure
+ things don't get out of sync, we clear the node in od_fast_nodes
+ *before* calling PyDict_DelItem.
+
+ The same must be done for any other OrderedDict operations where
+ we modify od_fast_nodes.
+*/
+static int
+_odict_clear_node(PyODictObject *od, _ODictNode *node, PyObject *key)
+{
+ Py_ssize_t i;
+
+ assert(key != NULL);
+ if (_odict_EMPTY(od)) {
+ /* Let later code decide if this is a KeyError. */
+ return 0;
+ }
+
+ i = _odict_get_index(od, key);
+ if (i < 0)
+ return PyErr_Occurred() ? -1 : 0;
+
+ if (node == NULL)
+ node = od->od_fast_nodes[i];
+ assert(node == od->od_fast_nodes[i]);
+ if (node == NULL) {
+ /* Let later code decide if this is a KeyError. */
+ return 0;
+ }
+
+ // Now clear the node.
+ od->od_fast_nodes[i] = NULL;
+ _odict_remove_node(od, node);
+ _odictnode_DEALLOC(node);
+ return 0;
+}
+
+static void
+_odict_clear_nodes(PyODictObject *od)
+{
+ _ODictNode *node, *next;
+
+ if (!_odict_EMPTY(od)) {
+ node = _odict_FIRST(od);
+ while (node != NULL) {
+ next = _odictnode_NEXT(node);
+ _odictnode_DEALLOC(node);
+ node = next;
+ }
+ _odict_FIRST(od) = NULL;
+ _odict_LAST(od) = NULL;
+ }
+
+ _odict_free_fast_nodes(od);
+ od->od_fast_nodes = NULL;
+}
+
+/* There isn't any memory management of nodes past this point. */
+#undef _odictnode_DEALLOC
+
+static int
+_odict_keys_equal(PyODictObject *a, PyODictObject *b)
+{
+ _ODictNode *node_a, *node_b;
+
+ node_a = _odict_FIRST(a);
+ node_b = _odict_FIRST(b);
+ while (1) {
+ if (node_a == NULL && node_b == NULL)
+ /* success: hit the end of each at the same time */
+ return 1;
+ else if (node_a == NULL || node_b == NULL)
+ /* unequal length */
+ return 0;
+ else {
+ int res = PyObject_RichCompareBool(
+ (PyObject *)_odictnode_KEY(node_a),
+ (PyObject *)_odictnode_KEY(node_b),
+ Py_EQ);
+ if (res < 0)
+ return res;
+ else if (res == 0)
+ return 0;
+
+ /* otherwise it must match, so move on to the next one */
+ node_a = _odictnode_NEXT(node_a);
+ node_b = _odictnode_NEXT(node_b);
+ }
+ }
+}
+
+
+/* ----------------------------------------------
+ * OrderedDict mapping methods
+ */
+
+/* mp_ass_subscript: __setitem__() and __delitem__() */
+
+static int
+odict_mp_ass_sub(PyODictObject *od, PyObject *v, PyObject *w)
+{
+ if (w == NULL)
+ return PyODict_DelItem((PyObject *)od, v);
+ else
+ return PyODict_SetItem((PyObject *)od, v, w);
+}
+
+/* tp_as_mapping */
+
+static PyMappingMethods odict_as_mapping = {
+ 0, /*mp_length*/
+ 0, /*mp_subscript*/
+ (objobjargproc)odict_mp_ass_sub, /*mp_ass_subscript*/
+};
+
+
+/* ----------------------------------------------
+ * OrderedDict methods
+ */
+
+/* __delitem__() */
+
+PyDoc_STRVAR(odict_delitem__doc__, "od.__delitem__(y) <==> del od[y]");
+
+/* __eq__() */
+
+PyDoc_STRVAR(odict_eq__doc__,
+"od.__eq__(y) <==> od==y. Comparison to another OD is order-sensitive \n\
+ while comparison to a regular mapping is order-insensitive.\n\
+ ");
+
+/* forward */
+static PyObject * odict_richcompare(PyObject *v, PyObject *w, int op);
+
+static PyObject *
+odict_eq(PyObject *a, PyObject *b)
+{
+ return odict_richcompare(a, b, Py_EQ);
+}
+
+/* __init__() */
+
+PyDoc_STRVAR(odict_init__doc__,
+"Initialize an ordered dictionary. The signature is the same as\n\
+ regular dictionaries, but keyword arguments are not recommended because\n\
+ their insertion order is arbitrary.\n\
+\n\
+ ");
+
+/* forward */
+static int odict_init(PyObject *self, PyObject *args, PyObject *kwds);
+
+/* __iter__() */
+
+PyDoc_STRVAR(odict_iter__doc__, "od.__iter__() <==> iter(od)");
+
+static PyObject * odict_iter(PyODictObject *self); /* forward */
+
+/* __ne__() */
+
+/* Mapping.__ne__() does not have a docstring. */
+PyDoc_STRVAR(odict_ne__doc__, "");
+
+static PyObject *
+odict_ne(PyObject *a, PyObject *b)
+{
+ return odict_richcompare(a, b, Py_NE);
+}
+
+/* __repr__() */
+
+PyDoc_STRVAR(odict_repr__doc__, "od.__repr__() <==> repr(od)");
+
+static PyObject * odict_repr(PyODictObject *self); /* forward */
+
+/* __setitem__() */
+
+PyDoc_STRVAR(odict_setitem__doc__, "od.__setitem__(i, y) <==> od[i]=y");
+
+/* fromkeys() */
+
+PyDoc_STRVAR(odict_fromkeys__doc__,
+"OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S.\n\
+ If not specified, the value defaults to None.\n\
+\n\
+ ");
+
+static PyObject *
+odict_fromkeys(PyObject *cls, PyObject *args)
+{
+ PyObject *seq;
+ PyObject *value = Py_None;
+ if (!PyArg_UnpackTuple(args, "fromkeys", 1, 2, &seq, &value)) /* borrowed */
+ return NULL;
+ return _PyDict_FromKeys(cls, seq, value);
+}
+
+/* __sizeof__() */
+
+/* OrderedDict.__sizeof__() does not have a docstring. */
+PyDoc_STRVAR(odict_sizeof__doc__, "");
+
+static PyObject *
+odict_sizeof(PyODictObject *od)
+{
+ PyObject *pylong;
+ Py_ssize_t res;
+
+ pylong = _PyDict_SizeOf((PyDictObject *)od);
+ if (pylong == NULL)
+ return NULL;
+ res = PyLong_AsSsize_t(pylong);
+ Py_DECREF(pylong);
+ if (res == -1 && PyErr_Occurred())
+ return NULL;
+
+ res += sizeof(PyODictObject) - sizeof(PyDictObject);
+
+ /* instance dict */
+ pylong = _PyDict_SizeOf((PyDictObject *)od->od_inst_dict);
+ if (pylong == NULL)
+ return NULL;
+ res += PyLong_AsSsize_t(pylong);
+ Py_DECREF(pylong);
+ if (res == -1 && PyErr_Occurred())
+ return NULL;
+
+ res += sizeof(_ODictNode) * od->od_size; /* od_fast_nodes */
+ if (!_odict_EMPTY(od)) {
+ res += sizeof(_ODictNode) * PyODict_SIZE(od); /* linked-list */
+ }
+ return PyLong_FromSsize_t(res);
+}
+
+/* __reduce__() */
+
+PyDoc_STRVAR(odict_reduce__doc__, "Return state information for pickling");
+
+static PyObject *
+odict_reduce(register PyODictObject *od)
+{
+ _Py_IDENTIFIER(__dict__);
+ _Py_IDENTIFIER(__class__);
+ PyObject *vars = NULL, *ns = NULL, *result = NULL, *cls = NULL;
+ PyObject *items_iter = NULL, *items = NULL, *args = NULL;
+
+ /* capture any instance state */
+ vars = _PyObject_GetAttrId((PyObject *)od, &PyId___dict__);
+ if (vars != NULL) {
+ PyObject *empty, *od_vars, *iterator, *key;
+
+ /* od.__dict__ isn't necessarily a dict... */
+ ns = PyObject_CallMethod((PyObject *)vars, "copy", NULL);
+ if (ns == NULL)
+ goto Done;
+ empty = PyODict_New();
+ if (empty == NULL)
+ goto Done;
+ od_vars = _PyObject_GetAttrId((PyObject *)empty, &PyId___dict__);
+ Py_DECREF(empty);
+ if (od_vars == NULL)
+ goto Done;
+ iterator = PyObject_GetIter(od_vars);
+ Py_DECREF(od_vars);
+ if (iterator == NULL)
+ goto Done;
+
+ while ( (key = PyIter_Next(iterator)) ) {
+ if (PyMapping_HasKey(ns, key) && PyMapping_DelItem(ns, key) != 0) {
+ Py_DECREF(iterator);
+ Py_DECREF(key);
+ goto Done;
+ }
+ Py_DECREF(key);
+ }
+ Py_DECREF(iterator);
+ if (PyErr_Occurred())
+ goto Done;
+
+ if (!PyObject_Length(ns)) {
+ /* nothing novel to pickle in od.__dict__ */
+ Py_DECREF(ns);
+ ns = NULL;
+ }
+ }
+
+ /* build the result */
+ cls = _PyObject_GetAttrId((PyObject *)od, &PyId___class__);
+ if (cls == NULL)
+ goto Done;
+
+ args = PyTuple_New(0);
+ if (args == NULL)
+ goto Done;
+
+ items = PyObject_CallMethod((PyObject *)od, "items", NULL);
+ if (items == NULL)
+ goto Done;
+
+ items_iter = PyObject_GetIter(items);
+ if (items_iter == NULL)
+ goto Done;
+
+ result = PyTuple_Pack(5, cls, args, ns ? ns : Py_None, Py_None, items_iter);
+
+Done:
+ Py_XDECREF(vars);
+ Py_XDECREF(ns);
+ Py_XDECREF(cls);
+ Py_XDECREF(args);
+ Py_XDECREF(items);
+ Py_XDECREF(items_iter);
+
+ return result;
+}
+
+/* setdefault() */
+
+PyDoc_STRVAR(odict_setdefault__doc__,
+ "od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od");
+
+/* Skips __missing__() calls. */
+static PyObject *
+odict_setdefault(register PyODictObject *od, PyObject *args)
+{
+ _ODictNode *node;
+ PyObject *key, *result = NULL;
+ PyObject *failobj = Py_None;
+
+ /* both borrowed */
+ if (!PyArg_UnpackTuple(args, "setdefault", 1, 2, &key, &failobj))
+ return NULL;
+ Py_INCREF(key);
+ Py_INCREF(failobj);
+
+ if (PyODict_CheckExact(od)) {
+ node = _odict_find_node(od, key);
+ if (node == NULL) {
+ if (PyErr_Occurred()) {
+ goto done;
+ }
+ else if (PyODict_SetItem((PyObject *)od, key, failobj) >= 0) {
+ result = failobj;
+ Py_INCREF(failobj);
+ }
+ }
+ else {
+ result = PyODict_GetItem(od, key); /* borrowed reference */
+ Py_XINCREF(result);
+ }
+ }
+ else {
+ int exists = PySequence_Contains((PyObject *)od, key);
+ if (exists < 0) {
+ goto done;
+ }
+ else if (exists) {
+ result = PyObject_GetItem((PyObject *)od, key);
+ }
+ else if (PyObject_SetItem((PyObject *)od, key, failobj) >= 0) {
+ result = failobj;
+ Py_INCREF(failobj);
+ }
+ }
+
+done:
+ Py_DECREF(failobj);
+ Py_DECREF(key);
+ return result;
+}
+
+/* pop() */
+
+PyDoc_STRVAR(odict_pop__doc__,
+"od.pop(k[,d]) -> v, remove specified key and return the corresponding\n\
+ value. If key is not found, d is returned if given, otherwise KeyError\n\
+ is raised.\n\
+\n\
+ ");
+
+/* forward */
+static PyObject * _odict_popkey(PyObject *, PyObject *, PyObject *);
+
+/* Skips __missing__() calls. */
+static PyObject *
+odict_pop(PyObject *od, PyObject *args)
+{
+ PyObject *key, *failobj = NULL;
+
+ if (!PyArg_UnpackTuple(args, "pop", 1, 2, &key, &failobj)) { /* borrowed */
+ return NULL;
+ }
+
+ return _odict_popkey(od, key, failobj);
+}
+
+static PyObject *
+_odict_popkey(PyObject *od, PyObject *key, PyObject *failobj)
+{
+ _ODictNode *node;
+ PyObject *value = NULL;
+
+ Py_INCREF(key);
+ Py_XINCREF(failobj);
+
+ /* Pop the node first to avoid a possible dict resize (due to
+ eval loop reentrancy) and complications due to hash collision
+ resolution. */
+ node = _odict_find_node((PyODictObject *)od, key);
+ if (node == NULL) {
+ if (PyErr_Occurred())
+ goto done;
+ }
+ else {
+ int res = _odict_clear_node((PyODictObject *)od, node, key);
+ if (res < 0) {
+ goto done;
+ }
+ }
+
+ /* Now delete the value from the dict. */
+ if (PyODict_CheckExact(od)) {
+ if (node != NULL) {
+ /* We could do PyDict_GetItem() and PyDict_DelItem() directly... */
+ value = _PyDict_Pop((PyDictObject *)od, key, failobj);
+ }
+ }
+ else {
+ int exists = PySequence_Contains(od, key);
+ if (exists < 0)
+ goto done;
+ if (exists) {
+ value = PyObject_GetItem(od, key);
+ if (value != NULL) {
+ if (PyObject_DelItem(od, key) == -1) {
+ Py_DECREF(value);
+ value = NULL;
+ }
+ }
+ }
+ }
+
+ /* Apply the fallback value, if necessary. */
+ if (value == NULL && !PyErr_Occurred()) {
+ if (failobj) {
+ value = failobj;
+ Py_INCREF(failobj);
+ }
+ else {
+ PyErr_SetObject(PyExc_KeyError, key);
+ }
+ }
+
+done:
+ Py_DECREF(key);
+ Py_XDECREF(failobj);
+ return value;
+}
+
+/* popitem() */
+
+PyDoc_STRVAR(odict_popitem__doc__,
+"od.popitem() -> (k, v), return and remove a (key, value) pair.\n\
+ Pairs are returned in LIFO order if last is true or FIFO order if false.\n\
+\n\
+ ");
+
+static PyObject *
+odict_popitem(PyObject *od, PyObject *args)
+{
+ PyObject *key, *value, *item = NULL, *last = NULL;
+ _ODictNode *node;
+
+ if (_odict_EMPTY((PyODictObject *)od)) {
+ PyErr_SetString(PyExc_KeyError, "dictionary is empty");
+ return NULL;
+ }
+
+ /* pull the item */
+
+ if (!PyArg_UnpackTuple(args, "popitem", 0, 1, &last)) /* borrowed */
+ return NULL;
+ Py_XINCREF(last);
+
+ if (last == NULL || last == Py_True)
+ node = _odict_LAST((PyODictObject *)od);
+ else
+ node = _odict_FIRST((PyODictObject *)od);
+ Py_XDECREF(last);
+
+ key = _odictnode_KEY(node);
+ value = _odict_popkey(od, key, NULL);
+ if (value == NULL)
+ return NULL;
+ item = PyTuple_Pack(2, key, value);
+ Py_DECREF(value);
+ return item;
+}
+
+/* keys() */
+
+/* MutableMapping.keys() does not have a docstring. */
+PyDoc_STRVAR(odict_keys__doc__, "");
+
+static PyObject * odictkeys_new(PyObject *od); /* forward */
+
+/* values() */
+
+/* MutableMapping.values() does not have a docstring. */
+PyDoc_STRVAR(odict_values__doc__, "");
+
+static PyObject * odictvalues_new(PyObject *od); /* forward */
+
+/* items() */
+
+/* MutableMapping.items() does not have a docstring. */
+PyDoc_STRVAR(odict_items__doc__, "");
+
+static PyObject * odictitems_new(PyObject *od); /* forward */
+
+/* update() */
+
+/* MutableMapping.update() does not have a docstring. */
+PyDoc_STRVAR(odict_update__doc__, "");
+
+/* forward */
+static PyObject * mutablemapping_update(PyObject *, PyObject *, PyObject *);
+
+#define odict_update mutablemapping_update
+
+/* clear() */
+
+PyDoc_STRVAR(odict_clear__doc__,
+ "od.clear() -> None. Remove all items from od.");
+
+static PyObject *
+odict_clear(register PyODictObject *od)
+{
+ PyDict_Clear((PyObject *)od);
+ _odict_clear_nodes(od);
+ _odict_FIRST(od) = NULL;
+ _odict_LAST(od) = NULL;
+ if (_odict_resize(od) < 0)
+ return NULL;
+ Py_RETURN_NONE;
+}
+
+/* copy() */
+
+PyDoc_STRVAR(odict_copy__doc__, "od.copy() -> a shallow copy of od");
+
+static PyObject *
+odict_copy(register PyODictObject *od)
+{
+ _ODictNode *node;
+ PyObject *od_copy;
+
+ if (PyODict_CheckExact(od))
+ od_copy = PyODict_New();
+ else
+ od_copy = PyObject_CallFunctionObjArgs((PyObject *)Py_TYPE(od), NULL);
+ if (od_copy == NULL)
+ return NULL;
+
+ if (PyODict_CheckExact(od)) {
+ _odict_FOREACH(od, node) {
+ int res = PyODict_SetItem((PyObject *)od_copy,
+ _odictnode_KEY(node),
+ _odictnode_VALUE(node, od));
+ if (res != 0)
+ goto fail;
+ }
+ }
+ else {
+ _odict_FOREACH(od, node) {
+ int res;
+ PyObject *value = PyObject_GetItem((PyObject *)od,
+ _odictnode_KEY(node));
+ if (value == NULL)
+ goto fail;
+ res = PyObject_SetItem((PyObject *)od_copy,
+ _odictnode_KEY(node), value);
+ Py_DECREF(value);
+ if (res != 0)
+ goto fail;
+ }
+ }
+ return od_copy;
+
+fail:
+ Py_DECREF(od_copy);
+ return NULL;
+}
+
+/* __reversed__() */
+
+PyDoc_STRVAR(odict_reversed__doc__, "od.__reversed__() <==> reversed(od)");
+
+#define _odict_ITER_REVERSED 1
+#define _odict_ITER_KEYS 2
+#define _odict_ITER_VALUES 4
+
+/* forward */
+static PyObject * odictiter_new(PyODictObject *, int);
+
+static PyObject *
+odict_reversed(PyODictObject *od)
+{
+ if (_odict_EMPTY(od)) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new(od, _odict_ITER_KEYS|_odict_ITER_REVERSED);
+}
+
+/* move_to_end() */
+
+PyDoc_STRVAR(odict_move_to_end__doc__,
+"Move an existing element to the end (or beginning if last==False).\n\
+\n\
+ Raises KeyError if the element does not exist.\n\
+ When last=True, acts like a fast version of self[key]=self.pop(key).\n\
+\n\
+ ");
+
+static PyObject *
+odict_move_to_end(PyODictObject *od, PyObject *args)
+{
+ PyObject *key, *last = NULL;
+ Py_ssize_t pos = -1;
+
+ /* both borrowed */
+ if (!PyArg_UnpackTuple(args, "move_to_end", 1, 2, &key, &last))
+ return NULL;
+ Py_INCREF(key);
+ if (_odict_EMPTY(od)) {
+ PyErr_SetObject(PyExc_KeyError, key);
+ Py_DECREF(key);
+ return NULL;
+ }
+ if (last != NULL) {
+ Py_INCREF(last);
+ pos = PyObject_IsTrue(last) ? -1 : 0;
+ Py_DECREF(last);
+ }
+ if (pos == 0) {
+ /* Only move if not already the first one. */
+ PyObject *first_key = _odictnode_KEY(_odict_FIRST(od));
+ if (PyObject_RichCompareBool(key, first_key, Py_NE)) {
+ _ODictNode *node = _odict_pop_node(od, NULL, key);
+ if (node != NULL) {
+ _odict_add_head(od, node);
+ }
+ else {
+ if (!PyErr_Occurred())
+ PyErr_SetObject(PyExc_KeyError, key);
+ Py_DECREF(key);
+ return NULL;
+ }
+ }
+ }
+ else if (pos == -1) {
+ /* Only move if not already the last one. */
+ PyObject *last_key = _odictnode_KEY(_odict_LAST(od));
+ if (PyObject_RichCompareBool(key, last_key, Py_NE)) {
+ _ODictNode *node = _odict_pop_node(od, NULL, key);
+ if (node != NULL) {
+ _odict_add_tail(od, node);
+ }
+ else {
+ if (!PyErr_Occurred())
+ PyErr_SetObject(PyExc_KeyError, key);
+ Py_DECREF(key);
+ return NULL;
+ }
+ }
+ }
+ Py_DECREF(key);
+ Py_RETURN_NONE;
+}
+
+
+/* tp_methods */
+
+static PyMethodDef odict_methods[] = {
+
+ /* explicitly defined so we can align docstrings with
+ * collections.OrderedDict */
+ {"__delitem__", (PyCFunction)odict_mp_ass_sub, METH_NOARGS,
+ odict_delitem__doc__},
+ {"__eq__", (PyCFunction)odict_eq, METH_NOARGS,
+ odict_eq__doc__},
+ {"__init__", (PyCFunction)odict_init, METH_NOARGS,
+ odict_init__doc__},
+ {"__iter__", (PyCFunction)odict_iter, METH_NOARGS,
+ odict_iter__doc__},
+ {"__ne__", (PyCFunction)odict_ne, METH_NOARGS,
+ odict_ne__doc__},
+ {"__repr__", (PyCFunction)odict_repr, METH_NOARGS,
+ odict_repr__doc__},
+ {"__setitem__", (PyCFunction)odict_mp_ass_sub, METH_NOARGS,
+ odict_setitem__doc__},
+ {"fromkeys", (PyCFunction)odict_fromkeys, METH_VARARGS | METH_CLASS,
+ odict_fromkeys__doc__},
+
+ /* overridden dict methods */
+ {"__sizeof__", (PyCFunction)odict_sizeof, METH_NOARGS,
+ odict_sizeof__doc__},
+ {"__reduce__", (PyCFunction)odict_reduce, METH_NOARGS,
+ odict_reduce__doc__},
+ {"setdefault", (PyCFunction)odict_setdefault, METH_VARARGS,
+ odict_setdefault__doc__},
+ {"pop", (PyCFunction)odict_pop, METH_VARARGS,
+ odict_pop__doc__},
+ {"popitem", (PyCFunction)odict_popitem, METH_VARARGS,
+ odict_popitem__doc__},
+ {"keys", (PyCFunction)odictkeys_new, METH_NOARGS,
+ odict_keys__doc__},
+ {"values", (PyCFunction)odictvalues_new, METH_NOARGS,
+ odict_values__doc__},
+ {"items", (PyCFunction)odictitems_new, METH_NOARGS,
+ odict_items__doc__},
+ {"update", (PyCFunction)odict_update, METH_VARARGS | METH_KEYWORDS,
+ odict_update__doc__},
+ {"clear", (PyCFunction)odict_clear, METH_NOARGS,
+ odict_clear__doc__},
+ {"copy", (PyCFunction)odict_copy, METH_NOARGS,
+ odict_copy__doc__},
+
+ /* new methods */
+ {"__reversed__", (PyCFunction)odict_reversed, METH_NOARGS,
+ odict_reversed__doc__},
+ {"move_to_end", (PyCFunction)odict_move_to_end, METH_VARARGS,
+ odict_move_to_end__doc__},
+
+ {NULL, NULL} /* sentinel */
+};
+
+
+/* ----------------------------------------------
+ * OrderedDict members
+ */
+
+/* tp_members */
+
+static PyMemberDef odict_members[] = {
+ {"__dict__", T_OBJECT, offsetof(PyODictObject, od_inst_dict), READONLY},
+ {0}
+};
+
+
+/* ----------------------------------------------
+ * OrderedDict type slot methods
+ */
+
+/* tp_dealloc */
+
+static void
+odict_dealloc(PyODictObject *self)
+{
+ PyObject_GC_UnTrack(self);
+ Py_TRASHCAN_SAFE_BEGIN(self);
+ Py_XDECREF(self->od_inst_dict);
+ if (self->od_weakreflist != NULL)
+ PyObject_ClearWeakRefs((PyObject *)self);
+
+ _odict_clear_nodes(self);
+ Py_TRASHCAN_SAFE_END(self);
+
+ /* must be last */
+ PyDict_Type.tp_dealloc((PyObject *)self);
+};
+
+/* tp_repr */
+
+static PyObject *
+odict_repr(PyODictObject *self)
+{
+ int i;
+ const char *formatstr;
+ _Py_IDENTIFIER(__class__);
+ _Py_IDENTIFIER(__name__);
+ Py_ssize_t count = -1;
+ PyObject *pieces = NULL, *result = NULL, *cls = NULL;
+ PyObject *classname = NULL, *format = NULL, *args = NULL;
+ _ODictNode *node;
+
+ i = Py_ReprEnter((PyObject *)self);
+ if (i != 0) {
+ return i > 0 ? PyUnicode_FromString("...") : NULL;
+ }
+
+ if (PyODict_SIZE(self) == 0) {
+ /* "OrderedDict()" */
+ goto Finish;
+ }
+
+ if (PyODict_CheckExact(self)) {
+ pieces = PyList_New(PyODict_SIZE(self));
+ if (pieces == NULL)
+ goto Done;
+
+ _odict_FOREACH(self, node) {
+ PyObject *pair = PyTuple_Pack(2, _odictnode_KEY(node),
+ _odictnode_VALUE(node, self));
+ if (pair == NULL)
+ goto Done;
+
+ PyList_SET_ITEM(pieces, ++count, pair); /* steals reference */
+ }
+ }
+ else {
+ PyObject *items = PyObject_CallMethod((PyObject *)self, "items", NULL);
+ if (items == NULL)
+ goto Done;
+ pieces = PySequence_List(items);
+ Py_DECREF(items);
+ if(pieces == NULL)
+ goto Done;
+ }
+
+Finish:
+ cls = _PyObject_GetAttrId((PyObject *)self, &PyId___class__);
+ if (cls == NULL)
+ goto Done;
+ classname = _PyObject_GetAttrId(cls, &PyId___name__);
+ if (classname == NULL)
+ goto Done;
+
+ if (pieces == NULL) {
+ formatstr = "%s()";
+ args = PyTuple_Pack(1, classname);
+ }
+ else {
+ formatstr = "%s(%r)";
+ args = PyTuple_Pack(2, classname, pieces);
+ }
+ if (args == NULL)
+ goto Done;
+
+ format = PyUnicode_InternFromString(formatstr);
+ if (format == NULL)
+ goto Done;
+
+ result = PyUnicode_Format(format, args);
+Done:
+ Py_XDECREF(pieces);
+ Py_XDECREF(cls);
+ Py_XDECREF(classname);
+ Py_XDECREF(format);
+ Py_XDECREF(args);
+ Py_ReprLeave((PyObject *)self);
+ return result;
+};
+
+/* tp_doc */
+
+PyDoc_STRVAR(odict_doc,
+ "Dictionary that remembers insertion order");
+
+/* tp_traverse */
+
+static int
+odict_traverse(PyODictObject *od, visitproc visit, void *arg)
+{
+ Py_VISIT(od->od_inst_dict);
+ Py_VISIT(od->od_weakreflist);
+ return PyDict_Type.tp_traverse((PyObject *)od, visit, arg);
+}
+
+/* tp_clear */
+
+static int
+odict_tp_clear(PyODictObject *od)
+{
+ PyObject *res;
+ Py_CLEAR(od->od_inst_dict);
+ Py_CLEAR(od->od_weakreflist);
+ res = odict_clear(od);
+ if (res == NULL)
+ return -1;
+ Py_DECREF(res);
+ return 0;
+}
+
+/* tp_richcompare */
+
+static PyObject *
+odict_richcompare(PyObject *v, PyObject *w, int op)
+{
+ if (!PyODict_Check(v) || !PyDict_Check(w)) {
+ Py_RETURN_NOTIMPLEMENTED;
+ }
+
+ if (op == Py_EQ || op == Py_NE) {
+ PyObject *res, *cmp;
+ int eq;
+
+ cmp = PyDict_Type.tp_richcompare(v, w, op);
+ if (cmp == NULL)
+ return NULL;
+ if (!PyODict_Check(w))
+ return cmp;
+ if (op == Py_EQ && cmp == Py_False)
+ return cmp;
+ if (op == Py_NE && cmp == Py_True)
+ return cmp;
+ Py_DECREF(cmp);
+
+ /* Try comparing odict keys. */
+ eq = _odict_keys_equal((PyODictObject *)v, (PyODictObject *)w);
+ if (eq < 0)
+ return NULL;
+
+ res = (eq == (op == Py_EQ)) ? Py_True : Py_False;
+ Py_INCREF(res);
+ return res;
+ } else {
+ Py_RETURN_NOTIMPLEMENTED;
+ }
+};
+
+/* tp_iter */
+
+static PyObject *
+odict_iter(PyODictObject *od)
+{
+ return odictiter_new(od, _odict_ITER_KEYS);
+};
+
+/* tp_init */
+
+static int
+odict_init(PyObject *self, PyObject *args, PyObject *kwds)
+{
+ PyObject *res;
+ Py_ssize_t len = PyObject_Length(args);
+
+ if (len == -1)
+ return -1;
+ if (len > 1) {
+ char *msg = "expected at most 1 arguments, got %d";
+ PyErr_Format(PyExc_TypeError, msg, len);
+ return -1;
+ }
+
+ /* __init__() triggering update() is just the way things are! */
+ res = odict_update(self, args, kwds);
+ if (res == NULL) {
+ return -1;
+ } else {
+ Py_DECREF(res);
+ return 0;
+ }
+};
+
+/* tp_new */
+
+static PyObject *
+odict_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+ PyObject *od = PyDict_Type.tp_new(type, args, kwds);
+ if (od != NULL) {
+ ((PyODictObject *)od)->od_inst_dict = PyDict_New();
+ ((PyODictObject *)od)->od_weakreflist = NULL;
+ if (_odict_initialize((PyODictObject *)od) < 0)
+ return NULL;
+ }
+ return od;
+}
+
+/* PyODict_Type */
+
+PyTypeObject PyODict_Type = {
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
+ "collections.OrderedDict", /* tp_name */
+ sizeof(PyODictObject), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ (destructor)odict_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_reserved */
+ (reprfunc)odict_repr, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ &odict_as_mapping, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC,/* tp_flags */
+ odict_doc, /* tp_doc */
+ (traverseproc)odict_traverse, /* tp_traverse */
+ (inquiry)odict_tp_clear, /* tp_clear */
+ (richcmpfunc)odict_richcompare, /* tp_richcompare */
+ offsetof(PyODictObject, od_weakreflist), /* tp_weaklistoffset */
+ (getiterfunc)odict_iter, /* tp_iter */
+ 0, /* tp_iternext */
+ odict_methods, /* tp_methods */
+ odict_members, /* tp_members */
+ 0, /* tp_getset */
+ &PyDict_Type, /* tp_base */
+ 0, /* tp_dict */
+ 0, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ offsetof(PyODictObject, od_inst_dict), /* tp_dictoffset */
+ (initproc)odict_init, /* tp_init */
+ PyType_GenericAlloc, /* tp_alloc */
+ (newfunc)odict_new, /* tp_new */
+ 0, /* tp_free */
+};
+
+
+/* ----------------------------------------------
+ * the public OrderedDict API
+ */
+
+PyObject *
+PyODict_New(void) {
+ return odict_new(&PyODict_Type, NULL, NULL);
+};
+
+int
+PyODict_SetItem(PyObject *od, PyObject *key, PyObject *value) {
+ int res = PyDict_SetItem(od, key, value);
+ if (res == 0) {
+ res = _odict_add_new_node((PyODictObject *)od, key);
+ }
+ return res;
+};
+
+int
+PyODict_DelItem(PyObject *od, PyObject *key) {
+ int res = _odict_clear_node((PyODictObject *)od, NULL, key);
+ if (res < 0)
+ return -1;
+ return PyDict_DelItem(od, key);
+};
+
+
+/* -------------------------------------------
+ * The OrderedDict views (keys/values/items)
+ */
+
+typedef struct {
+ PyObject_HEAD
+ int kind;
+ PyODictObject *di_odict;
+ PyObject *di_current;
+ PyObject *di_result; /* reusable result tuple for iteritems */
+} odictiterobject;
+
+static void
+odictiter_dealloc(odictiterobject *di)
+{
+ _PyObject_GC_UNTRACK(di);
+ Py_DECREF(di->di_odict);
+ Py_XDECREF(di->di_current);
+ if (di->kind & (_odict_ITER_KEYS | _odict_ITER_VALUES)) {
+ Py_DECREF(di->di_result);
+ }
+ PyObject_GC_Del(di);
+}
+
+static int
+odictiter_traverse(odictiterobject *di, visitproc visit, void *arg)
+{
+ Py_VISIT(di->di_odict);
+ Py_VISIT(di->di_current); /* A key could be any type, not just str. */
+ Py_VISIT(di->di_result);
+ return 0;
+}
+
+static PyObject *
+odictiter_nextkey(odictiterobject *di)
+{
+ PyObject *key;
+ _ODictNode *node;
+ int reversed = di->kind & _odict_ITER_REVERSED;
+
+ /* Get the key. */
+ if (di->di_current == NULL)
+ return NULL;
+ node = _odict_find_node(di->di_odict, di->di_current);
+ if (node == NULL) {
+ /* Must have been deleted. */
+ Py_DECREF(di->di_current);
+ di->di_current = NULL;
+ return NULL;
+ }
+ key = di->di_current;
+
+ /* Advance to the next key. */
+ node = reversed ? _odictnode_PREV(node) : _odictnode_NEXT(node);
+ if (node == NULL) {
+ /* Reached the end. */
+ di->di_current = NULL;
+ }
+ else {
+ di->di_current = _odictnode_KEY(node);
+ Py_INCREF(di->di_current);
+ }
+
+ return key;
+}
+
+static PyObject *
+odictiter_iternext(odictiterobject *di)
+{
+ PyObject *value;
+ PyObject *key = odictiter_nextkey(di); /* new reference */
+
+ if (key == NULL)
+ return NULL;
+
+ /* Handle the keys case. */
+ if (! (di->kind & _odict_ITER_VALUES)) {
+ return key;
+ }
+
+ /* Handle the items case. */
+ if (di->kind & _odict_ITER_KEYS) {
+ PyObject *result = di->di_result;
+
+ value = PyODict_GetItem((PyObject *)di->di_odict, key); /* borrowed */
+
+ if (result->ob_refcnt == 1) {
+ /* not in use so we can reuse it
+ * (the common case during iteration) */
+ Py_INCREF(result);
+ Py_DECREF(PyTuple_GET_ITEM(result, 0)); /* borrowed */
+ Py_DECREF(PyTuple_GET_ITEM(result, 1)); /* borrowed */
+ }
+ else {
+ result = PyTuple_New(2);
+ if (result == NULL)
+ return NULL;
+ }
+
+ Py_INCREF(value);
+ PyTuple_SET_ITEM(result, 0, key); /* steals reference */
+ PyTuple_SET_ITEM(result, 1, value); /* steals reference */
+
+ return result;
+ }
+ /* Handle the values case. */
+ else {
+ value = PyODict_GetItem((PyObject *)di->di_odict, key);
+ Py_XINCREF(value);
+ Py_DECREF(key);
+ return value;
+ }
+}
+
+/* No need for tp_clear because odictiterobject is not mutable. */
+
+PyDoc_STRVAR(reduce_doc, "Return state information for pickling");
+
+static PyObject *
+odictiter_reduce(odictiterobject *di)
+{
+ PyObject *list;
+
+ list = PyList_New(0);
+ if (!list)
+ return NULL;
+
+ /* iterate the temporary into a list */
+ for(;;) {
+ PyObject *element = odictiter_iternext(di);
+ if (element) {
+ if (PyList_Append(list, element)) {
+ Py_DECREF(element);
+ Py_DECREF(list);
+ return NULL;
+ }
+ Py_DECREF(element);
+ }
+ else {
+ /* done iterating? */
+ break;
+ }
+ }
+ if (PyErr_Occurred()) {
+ Py_DECREF(list);
+ return NULL;
+ }
+ return Py_BuildValue("N(N)", _PyObject_GetBuiltin("iter"), list);
+}
+
+static PyMethodDef odictiter_methods[] = {
+ {"__reduce__", (PyCFunction)odictiter_reduce, METH_NOARGS, reduce_doc},
+ {NULL, NULL} /* sentinel */
+};
+
+PyTypeObject PyODictIter_Type = {
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
+ "odict_iterator", /* tp_name */
+ sizeof(odictiterobject), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ /* methods */
+ (destructor)odictiter_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_reserved */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ PyObject_GenericGetAttr, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, /* tp_flags */
+ 0, /* tp_doc */
+ (traverseproc)odictiter_traverse, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ PyObject_SelfIter, /* tp_iter */
+ (iternextfunc)odictiter_iternext, /* tp_iternext */
+ odictiter_methods, /* tp_methods */
+ 0,
+};
+
+static PyObject *
+odictiter_new(PyODictObject *od, int kind)
+{
+ odictiterobject *di;
+ _ODictNode *node;
+ int reversed = kind & _odict_ITER_REVERSED;
+
+ di = PyObject_GC_New(odictiterobject, &PyODictIter_Type);
+ if (di == NULL)
+ return NULL;
+
+ if (kind & (_odict_ITER_KEYS | _odict_ITER_VALUES)){
+ di->di_result = PyTuple_Pack(2, Py_None, Py_None);
+ if (di->di_result == NULL) {
+ Py_DECREF(di);
+ return NULL;
+ }
+ }
+ else
+ di->di_result = NULL;
+
+ di->kind = kind;
+ node = reversed ? _odict_LAST(od) : _odict_FIRST(od);
+ di->di_current = node ? _odictnode_KEY(node) : NULL;
+ Py_XINCREF(di->di_current);
+ di->di_odict = od;
+ Py_INCREF(od);
+
+ _PyObject_GC_TRACK(di);
+ return (PyObject *)di;
+}
+
+/* keys() */
+
+static PyObject *
+odictkeys_iter(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_KEYS);
+}
+
+static PyObject *
+odictkeys_reversed(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_KEYS|_odict_ITER_REVERSED);
+}
+
+static PyMethodDef odictkeys_methods[] = {
+ {"__reversed__", (PyCFunction)odictkeys_reversed, METH_NOARGS, NULL},
+ {NULL, NULL} /* sentinel */
+};
+
+PyTypeObject PyODictKeys_Type = {
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
+ "odict_keys", /* tp_name */
+ 0, /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_reserved */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ 0, /* tp_flags */
+ 0, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ (getiterfunc)odictkeys_iter, /* tp_iter */
+ 0, /* tp_iternext */
+ odictkeys_methods, /* tp_methods */
+ 0, /* tp_members */
+ 0, /* tp_getset */
+ &PyDictKeys_Type, /* tp_base */
+};
+
+static PyObject *
+odictkeys_new(PyObject *od)
+{
+ return _PyDictView_New(od, &PyODictKeys_Type);
+}
+
+/* items() */
+
+static PyObject *
+odictitems_iter(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_KEYS|_odict_ITER_VALUES);
+}
+
+static PyObject *
+odictitems_reversed(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_KEYS|_odict_ITER_VALUES|_odict_ITER_REVERSED);
+}
+
+static PyMethodDef odictitems_methods[] = {
+ {"__reversed__", (PyCFunction)odictitems_reversed, METH_NOARGS, NULL},
+ {NULL, NULL} /* sentinel */
+};
+
+PyTypeObject PyODictItems_Type = {
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
+ "odict_items", /* tp_name */
+ 0, /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_reserved */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ 0, /* tp_flags */
+ 0, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ (getiterfunc)odictitems_iter, /* tp_iter */
+ 0, /* tp_iternext */
+ odictitems_methods, /* tp_methods */
+ 0, /* tp_members */
+ 0, /* tp_getset */
+ &PyDictItems_Type, /* tp_base */
+};
+
+static PyObject *
+odictitems_new(PyObject *od)
+{
+ return _PyDictView_New(od, &PyODictItems_Type);
+}
+
+/* values() */
+
+static PyObject *
+odictvalues_iter(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_VALUES);
+}
+
+static PyObject *
+odictvalues_reversed(_PyDictViewObject *dv)
+{
+ if (dv->dv_dict == NULL) {
+ Py_RETURN_NONE;
+ }
+ return odictiter_new((PyODictObject *)dv->dv_dict,
+ _odict_ITER_VALUES|_odict_ITER_REVERSED);
+}
+
+static PyMethodDef odictvalues_methods[] = {
+ {"__reversed__", (PyCFunction)odictvalues_reversed, METH_NOARGS, NULL},
+ {NULL, NULL} /* sentinel */
+};
+
+PyTypeObject PyODictValues_Type = {
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
+ "odict_values", /* tp_name */
+ 0, /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_reserved */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ 0, /* tp_flags */
+ 0, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ (getiterfunc)odictvalues_iter, /* tp_iter */
+ 0, /* tp_iternext */
+ odictvalues_methods, /* tp_methods */
+ 0, /* tp_members */
+ 0, /* tp_getset */
+ &PyDictValues_Type, /* tp_base */
+};
+
+static PyObject *
+odictvalues_new(PyObject *od)
+{
+ return _PyDictView_New(od, &PyODictValues_Type);
+}
+
+
+/* ----------------------------------------------
+ MutableMappping implementations
+
+Mapping:
+
+============ ===========
+method uses
+============ ===========
+__contains__ __getitem__
+__eq__ items
+__getitem__ +
+__iter__ +
+__len__ +
+__ne__ __eq__
+get __getitem__
+items ItemsView
+keys KeysView
+values ValuesView
+============ ===========
+
+ItemsView uses __len__, __iter__, and __getitem__.
+KeysView uses __len__, __iter__, and __contains__.
+ValuesView uses __len__, __iter__, and __getitem__.
+
+MutableMapping:
+
+============ ===========
+method uses
+============ ===========
+__delitem__ +
+__setitem__ +
+clear popitem
+pop __getitem__
+ __delitem__
+popitem __iter__
+ _getitem__
+ __delitem__
+setdefault __getitem__
+ __setitem__
+update __setitem__
+============ ===========
+*/
+
+static int
+mutablemapping_add_pairs(PyObject *self, PyObject *pairs)
+{
+ PyObject *pair, *iterator, *unexpected;
+ int res = 0;
+
+ iterator = PyObject_GetIter(pairs);
+ if (iterator == NULL)
+ return -1;
+ PyErr_Clear();
+
+ while ((pair = PyIter_Next(iterator)) != NULL) {
+ /* could be more efficient (see UNPACK_SEQUENCE in ceval.c) */
+ PyObject * key, *value = NULL;
+ PyObject *pair_iterator = PyObject_GetIter(pair);
+
+ key = PyIter_Next(pair_iterator);
+ if (key == NULL) {
+ if (!PyErr_Occurred())
+ PyErr_SetString(PyExc_ValueError,
+ "need more than 0 values to unpack");
+ goto Done;
+ }
+
+ value = PyIter_Next(pair_iterator);
+ if (value == NULL) {
+ if (!PyErr_Occurred())
+ PyErr_SetString(PyExc_ValueError,
+ "need more than 1 value to unpack");
+ goto Done;
+ }
+
+ unexpected = PyIter_Next(pair_iterator);
+ if (unexpected != NULL) {
+ Py_DECREF(unexpected);
+ PyErr_SetString(PyExc_ValueError,
+ "too many values to unpack (expected 2)");
+ goto Done;
+ }
+ else if (PyErr_Occurred())
+ goto Done;
+
+ res = PyObject_SetItem(self, key, value);
+
+Done:
+ Py_DECREF(pair);
+ Py_DECREF(pair_iterator);
+ Py_XDECREF(key);
+ Py_XDECREF(value);
+ if (PyErr_Occurred())
+ break;
+ }
+ Py_DECREF(iterator);
+
+ if (res < 0 || PyErr_Occurred() != NULL)
+ return -1;
+ else
+ return 0;
+}
+
+static PyObject *
+mutablemapping_update(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+ int res = 0;
+ Py_ssize_t len = (args != NULL) ? PyObject_Size(args) : 0;
+
+ /* first handle args, if any */
+ if (len < 0)
+ return NULL;
+ else if (len > 1) {
+ char *msg = "update() takes at most 1 positional argument (%d given)";
+ PyErr_Format(PyExc_TypeError, msg, len);
+ return NULL;
+ }
+ else if (len == 1) {
+ PyObject *other = PyTuple_GET_ITEM(args, 0); /* borrowed reference */
+ if (other == NULL)
+ return NULL;
+ Py_INCREF(other);
+ if (PyObject_HasAttrString(other, "items")) {
+ PyObject *items = PyMapping_Items(other);
+ Py_DECREF(other);
+ if (items == NULL)
+ return NULL;
+ res = mutablemapping_add_pairs(self, items);
+ Py_DECREF(items);
+ if (res == -1)
+ return NULL;
+ }
+ else if (PyObject_HasAttrString(other, "keys")) {
+ PyObject *keys, *iterator, *key;
+ keys = PyObject_CallMethod(other, "keys", NULL);
+ Py_DECREF(other);
+ if (keys == NULL)
+ return NULL;
+ iterator = PyObject_GetIter(keys);
+ Py_DECREF(keys);
+ if (iterator == NULL)
+ return NULL;
+ while (res == 0 && (key = PyIter_Next(iterator))) {
+ PyObject *value = PyObject_GetItem(other, key);
+ if (value != NULL) {
+ res = PyObject_SetItem(self, key, value);
+ Py_DECREF(value);
+ }
+ else {
+ res = -1;
+ }
+ Py_DECREF(key);
+ }
+ Py_DECREF(iterator);
+ if (res != 0 || PyErr_Occurred())
+ return NULL;
+ }
+ else {
+ res = mutablemapping_add_pairs(self, other);
+ Py_DECREF(other);
+ if (res != 0)
+ return NULL;
+ }
+ }
+
+ /* now handle kwargs */
+ len = (kwargs != NULL) ? PyObject_Size(kwargs) : 0;
+ if (len < 0)
+ return NULL;
+ else if (len > 0) {
+ PyObject *items;
+ if (!PyMapping_Check(kwargs)) {
+ PyErr_SetString(PyExc_TypeError, "expected mapping for kwargs");
+ return NULL;
+ }
+ items = PyMapping_Items(kwargs);
+ if (items == NULL)
+ return NULL;
+ res = mutablemapping_add_pairs(self, items);
+ Py_DECREF(items);
+ if (res == -1)
+ return NULL;
+ }
+
+ Py_RETURN_NONE;
+}