--- a/src/cx/iterator.h Thu May 23 18:21:36 2024 +0200
+++ b/src/cx/iterator.h Thu May 23 19:29:14 2024 +0200
@@ -38,68 +38,64 @@
#include "common.h"
-/**
- * The base of mutating and non-mutating iterators.
- */
-struct cx_iterator_base_s {
- /**
- * True iff the iterator points to valid data.
- */
- __attribute__ ((__nonnull__))
- bool (*valid)(void const *);
+#define CX_ITERATOR_BASE \
+ /** \
+ * True iff the iterator points to valid data. \
+ */ \
+ __attribute__ ((__nonnull__)) \
+ bool (*valid)(void const *); \
+ /** \
+ * Returns a pointer to the current element. \
+ * \
+ * When valid returns false, the behavior of this function is undefined. \
+ */ \
+ __attribute__ ((__nonnull__)) \
+ void *(*current)(void const *); \
+ /** \
+ * Original implementation in case the function needs to be wrapped. \
+ */ \
+ __attribute__ ((__nonnull__)) \
+ void *(*current_impl)(void const *); \
+ /** \
+ * Advances the iterator. \
+ * \
+ * When valid returns false, the behavior of this function is undefined. \
+ */ \
+ __attribute__ ((__nonnull__)) \
+ void (*next)(void *); \
+ /** \
+ * Indicates whether this iterator may remove elements. \
+ */ \
+ bool mutating; \
+ /** \
+ * Internal flag for removing the current element when advancing. \
+ */ \
+ bool remove;
- /**
- * Returns a pointer to the current element.
- *
- * When valid returns false, the behavior of this function is undefined.
- */
- __attribute__ ((__nonnull__))
- void *(*current)(void const *);
-
- /**
- * Original implementation in case the function needs to be wrapped.
- */
- __attribute__ ((__nonnull__))
- void *(*current_impl)(void const *);
+/**
+ * Internal iterator struct - use CxIterator.
+ */
+struct cx_iterator_s {
+ CX_ITERATOR_BASE
/**
- * Advances the iterator.
- *
- * When valid returns false, the behavior of this function is undefined.
- */
- __attribute__ ((__nonnull__))
- void (*next)(void *);
-
- /**
- * Indicates whether this iterator may remove elements.
- */
- bool mutating;
-
- /**
- * Internal flag for removing the current element when advancing.
- */
- bool remove;
-};
-
-/**
- * Internal iterator struct - use CxMutIterator.
- */
-struct cx_mut_iterator_s {
-
- /**
- * The base properties of this iterator.
- */
- struct cx_iterator_base_s base;
-
- /**
- * Handle for the current element, if required.
+ * Handle for the current element.
*/
void *elem_handle;
/**
* Handle for the source collection, if any.
*/
- void *src_handle;
+ union {
+ /**
+ * Access for mutating iterators.
+ */
+ void *m;
+ /**
+ * Access for normal iterators.
+ */
+ void const *c;
+ } src_handle;
/**
* Field for storing a key-value pair.
@@ -141,91 +137,15 @@
};
/**
- * Mutating iterator value type.
- *
- * An iterator points to a certain element in an (possibly unbounded) chain of elements.
- * Iterators that are based on collections (which have a defined "first" element), are supposed
- * to be "position-aware", which means that they keep track of the current index within the collection.
- *
- * @note Objects that are pointed to by an iterator are mutable through that iterator. However, if the
- * iterator is based on a collection and the underlying collection is mutated by other means than this iterator
- * (e.g. elements added or removed), the iterator becomes invalid (regardless of what cxIteratorValid() returns)
- * and MUST be re-obtained from the collection.
+ * Iterator type.
*
- * @see CxIterator
- */
-typedef struct cx_mut_iterator_s CxMutIterator;
-
-/**
- * Internal iterator struct - use CxIterator.
- */
-struct cx_iterator_s {
-
- /**
- * The base properties of this iterator.
- */
- struct cx_iterator_base_s base;
-
- /**
- * Handle for the current element, if required.
- */
- void *elem_handle;
-
- /**
- * Handle for the source collection, if any.
- */
- void const *src_handle;
-
- /**
- * Field for storing a key-value pair.
- * May be used by iterators that iterate over k/v-collections.
- */
- struct {
- /**
- * A pointer to the key.
- */
- void const *key;
- /**
- * A pointer to the value.
- */
- void *value;
- } kv_data;
-
- /**
- * Field for storing a slot number.
- * May be used by iterators that iterate over multi-bucket collections.
- */
- size_t slot;
-
- /**
- * If the iterator is position-aware, contains the index of the element in the underlying collection.
- * Otherwise, this field is usually uninitialized.
- */
- size_t index;
-
- /**
- * The size of an individual element.
- */
- size_t elem_size;
-
- /**
- * May contain the total number of elements, if known.
- * Shall be set to \c SIZE_MAX when the total number is unknown during iteration.
- */
- size_t elem_count;
-};
-
-/**
- * Iterator value type.
* An iterator points to a certain element in a (possibly unbounded) chain of elements.
* Iterators that are based on collections (which have a defined "first" element), are supposed
* to be "position-aware", which means that they keep track of the current index within the collection.
*
* @note Objects that are pointed to by an iterator are always mutable through that iterator. However,
- * this iterator cannot mutate the collection itself (add or remove elements) and any mutation of the
- * collection by other means makes this iterator invalid (regardless of what cxIteratorValid() returns).
- *
- * @see CxMutIterator
+ * any concurrent mutation of the collection other than by this iterator makes this iterator invalid
+ * and it must not be used anymore.
*/
typedef struct cx_iterator_s CxIterator;
@@ -237,7 +157,7 @@
* @param iter the iterator
* @return true iff the iterator points to valid data
*/
-#define cxIteratorValid(iter) (iter).base.valid(&(iter))
+#define cxIteratorValid(iter) (iter).valid(&(iter))
/**
* Returns a pointer to the current element.
@@ -247,21 +167,21 @@
* @param iter the iterator
* @return a pointer to the current element
*/
-#define cxIteratorCurrent(iter) (iter).base.current(&iter)
+#define cxIteratorCurrent(iter) (iter).current(&iter)
/**
* Advances the iterator to the next element.
*
* @param iter the iterator
*/
-#define cxIteratorNext(iter) (iter).base.next(&iter)
+#define cxIteratorNext(iter) (iter).next(&iter)
/**
* Flags the current element for removal, if this iterator is mutating.
*
* @param iter the iterator
*/
-#define cxIteratorFlagRemoval(iter) (iter).base.remove |= (iter).base.mutating
+#define cxIteratorFlagRemoval(iter) (iter).remove |= (iter).mutating
/**
* Loops over an iterator.
@@ -316,7 +236,7 @@
* @return an iterator for the specified array
*/
__attribute__((__warn_unused_result__))
-CxMutIterator cxMutIterator(
+CxIterator cxMutIterator(
void *array,
size_t elem_size,
size_t elem_count,