1.1 --- a/src/cx/iterator.h Thu May 23 18:21:36 2024 +0200
1.2 +++ b/src/cx/iterator.h Thu May 23 19:29:14 2024 +0200
1.3 @@ -38,68 +38,64 @@
1.4
1.5 #include "common.h"
1.6
1.7 +#define CX_ITERATOR_BASE \
1.8 + /** \
1.9 + * True iff the iterator points to valid data. \
1.10 + */ \
1.11 + __attribute__ ((__nonnull__)) \
1.12 + bool (*valid)(void const *); \
1.13 + /** \
1.14 + * Returns a pointer to the current element. \
1.15 + * \
1.16 + * When valid returns false, the behavior of this function is undefined. \
1.17 + */ \
1.18 + __attribute__ ((__nonnull__)) \
1.19 + void *(*current)(void const *); \
1.20 + /** \
1.21 + * Original implementation in case the function needs to be wrapped. \
1.22 + */ \
1.23 + __attribute__ ((__nonnull__)) \
1.24 + void *(*current_impl)(void const *); \
1.25 + /** \
1.26 + * Advances the iterator. \
1.27 + * \
1.28 + * When valid returns false, the behavior of this function is undefined. \
1.29 + */ \
1.30 + __attribute__ ((__nonnull__)) \
1.31 + void (*next)(void *); \
1.32 + /** \
1.33 + * Indicates whether this iterator may remove elements. \
1.34 + */ \
1.35 + bool mutating; \
1.36 + /** \
1.37 + * Internal flag for removing the current element when advancing. \
1.38 + */ \
1.39 + bool remove;
1.40 +
1.41 /**
1.42 - * The base of mutating and non-mutating iterators.
1.43 + * Internal iterator struct - use CxIterator.
1.44 */
1.45 -struct cx_iterator_base_s {
1.46 - /**
1.47 - * True iff the iterator points to valid data.
1.48 - */
1.49 - __attribute__ ((__nonnull__))
1.50 - bool (*valid)(void const *);
1.51 +struct cx_iterator_s {
1.52 + CX_ITERATOR_BASE
1.53
1.54 /**
1.55 - * Returns a pointer to the current element.
1.56 - *
1.57 - * When valid returns false, the behavior of this function is undefined.
1.58 - */
1.59 - __attribute__ ((__nonnull__))
1.60 - void *(*current)(void const *);
1.61 -
1.62 - /**
1.63 - * Original implementation in case the function needs to be wrapped.
1.64 - */
1.65 - __attribute__ ((__nonnull__))
1.66 - void *(*current_impl)(void const *);
1.67 -
1.68 - /**
1.69 - * Advances the iterator.
1.70 - *
1.71 - * When valid returns false, the behavior of this function is undefined.
1.72 - */
1.73 - __attribute__ ((__nonnull__))
1.74 - void (*next)(void *);
1.75 -
1.76 - /**
1.77 - * Indicates whether this iterator may remove elements.
1.78 - */
1.79 - bool mutating;
1.80 -
1.81 - /**
1.82 - * Internal flag for removing the current element when advancing.
1.83 - */
1.84 - bool remove;
1.85 -};
1.86 -
1.87 -/**
1.88 - * Internal iterator struct - use CxMutIterator.
1.89 - */
1.90 -struct cx_mut_iterator_s {
1.91 -
1.92 - /**
1.93 - * The base properties of this iterator.
1.94 - */
1.95 - struct cx_iterator_base_s base;
1.96 -
1.97 - /**
1.98 - * Handle for the current element, if required.
1.99 + * Handle for the current element.
1.100 */
1.101 void *elem_handle;
1.102
1.103 /**
1.104 * Handle for the source collection, if any.
1.105 */
1.106 - void *src_handle;
1.107 + union {
1.108 + /**
1.109 + * Access for mutating iterators.
1.110 + */
1.111 + void *m;
1.112 + /**
1.113 + * Access for normal iterators.
1.114 + */
1.115 + void const *c;
1.116 + } src_handle;
1.117
1.118 /**
1.119 * Field for storing a key-value pair.
1.120 @@ -141,91 +137,15 @@
1.121 };
1.122
1.123 /**
1.124 - * Mutating iterator value type.
1.125 + * Iterator type.
1.126 *
1.127 - * An iterator points to a certain element in an (possibly unbounded) chain of elements.
1.128 - * Iterators that are based on collections (which have a defined "first" element), are supposed
1.129 - * to be "position-aware", which means that they keep track of the current index within the collection.
1.130 - *
1.131 - * @note Objects that are pointed to by an iterator are mutable through that iterator. However, if the
1.132 - * iterator is based on a collection and the underlying collection is mutated by other means than this iterator
1.133 - * (e.g. elements added or removed), the iterator becomes invalid (regardless of what cxIteratorValid() returns)
1.134 - * and MUST be re-obtained from the collection.
1.135 - *
1.136 - * @see CxIterator
1.137 - */
1.138 -typedef struct cx_mut_iterator_s CxMutIterator;
1.139 -
1.140 -/**
1.141 - * Internal iterator struct - use CxIterator.
1.142 - */
1.143 -struct cx_iterator_s {
1.144 -
1.145 - /**
1.146 - * The base properties of this iterator.
1.147 - */
1.148 - struct cx_iterator_base_s base;
1.149 -
1.150 - /**
1.151 - * Handle for the current element, if required.
1.152 - */
1.153 - void *elem_handle;
1.154 -
1.155 - /**
1.156 - * Handle for the source collection, if any.
1.157 - */
1.158 - void const *src_handle;
1.159 -
1.160 - /**
1.161 - * Field for storing a key-value pair.
1.162 - * May be used by iterators that iterate over k/v-collections.
1.163 - */
1.164 - struct {
1.165 - /**
1.166 - * A pointer to the key.
1.167 - */
1.168 - void const *key;
1.169 - /**
1.170 - * A pointer to the value.
1.171 - */
1.172 - void *value;
1.173 - } kv_data;
1.174 -
1.175 - /**
1.176 - * Field for storing a slot number.
1.177 - * May be used by iterators that iterate over multi-bucket collections.
1.178 - */
1.179 - size_t slot;
1.180 -
1.181 - /**
1.182 - * If the iterator is position-aware, contains the index of the element in the underlying collection.
1.183 - * Otherwise, this field is usually uninitialized.
1.184 - */
1.185 - size_t index;
1.186 -
1.187 - /**
1.188 - * The size of an individual element.
1.189 - */
1.190 - size_t elem_size;
1.191 -
1.192 - /**
1.193 - * May contain the total number of elements, if known.
1.194 - * Shall be set to \c SIZE_MAX when the total number is unknown during iteration.
1.195 - */
1.196 - size_t elem_count;
1.197 -};
1.198 -
1.199 -/**
1.200 - * Iterator value type.
1.201 * An iterator points to a certain element in a (possibly unbounded) chain of elements.
1.202 * Iterators that are based on collections (which have a defined "first" element), are supposed
1.203 * to be "position-aware", which means that they keep track of the current index within the collection.
1.204 *
1.205 * @note Objects that are pointed to by an iterator are always mutable through that iterator. However,
1.206 - * this iterator cannot mutate the collection itself (add or remove elements) and any mutation of the
1.207 - * collection by other means makes this iterator invalid (regardless of what cxIteratorValid() returns).
1.208 - *
1.209 - * @see CxMutIterator
1.210 + * any concurrent mutation of the collection other than by this iterator makes this iterator invalid
1.211 + * and it must not be used anymore.
1.212 */
1.213 typedef struct cx_iterator_s CxIterator;
1.214
1.215 @@ -237,7 +157,7 @@
1.216 * @param iter the iterator
1.217 * @return true iff the iterator points to valid data
1.218 */
1.219 -#define cxIteratorValid(iter) (iter).base.valid(&(iter))
1.220 +#define cxIteratorValid(iter) (iter).valid(&(iter))
1.221
1.222 /**
1.223 * Returns a pointer to the current element.
1.224 @@ -247,21 +167,21 @@
1.225 * @param iter the iterator
1.226 * @return a pointer to the current element
1.227 */
1.228 -#define cxIteratorCurrent(iter) (iter).base.current(&iter)
1.229 +#define cxIteratorCurrent(iter) (iter).current(&iter)
1.230
1.231 /**
1.232 * Advances the iterator to the next element.
1.233 *
1.234 * @param iter the iterator
1.235 */
1.236 -#define cxIteratorNext(iter) (iter).base.next(&iter)
1.237 +#define cxIteratorNext(iter) (iter).next(&iter)
1.238
1.239 /**
1.240 * Flags the current element for removal, if this iterator is mutating.
1.241 *
1.242 * @param iter the iterator
1.243 */
1.244 -#define cxIteratorFlagRemoval(iter) (iter).base.remove |= (iter).base.mutating
1.245 +#define cxIteratorFlagRemoval(iter) (iter).remove |= (iter).mutating
1.246
1.247 /**
1.248 * Loops over an iterator.
1.249 @@ -316,7 +236,7 @@
1.250 * @return an iterator for the specified array
1.251 */
1.252 __attribute__((__warn_unused_result__))
1.253 -CxMutIterator cxMutIterator(
1.254 +CxIterator cxMutIterator(
1.255 void *array,
1.256 size_t elem_size,
1.257 size_t elem_count,
