comparison: ucx/iterator.c
ucx/iterator.c
- branch
- dav-2
- changeset 891
- 4d58cbcc9efa
- parent 889
- 42cdbf9bbd49
equal
deleted
inserted
replaced
| 890:e77ccf1c4bb3 | 891:4d58cbcc9efa |
|---|---|
| 27 */ | 27 */ |
| 28 | 28 |
| 29 #include "cx/iterator.h" | 29 #include "cx/iterator.h" |
| 30 | 30 |
| 31 #include <string.h> | 31 #include <string.h> |
| 32 #include <assert.h> | |
| 32 | 33 |
| 33 static bool cx_iter_valid(const void *it) { | 34 static bool cx_iter_valid(const void *it) { |
| 34 const struct cx_iterator_s *iter = it; | 35 const struct cx_iterator_s *iter = it; |
| 35 return iter->index < iter->elem_count; | 36 return iter->index < iter->elem_count; |
| 36 } | 37 } |
| 43 static void *cx_iter_current_ptr(const void *it) { | 44 static void *cx_iter_current_ptr(const void *it) { |
| 44 const struct cx_iterator_s *iter = it; | 45 const struct cx_iterator_s *iter = it; |
| 45 return *(void**)iter->elem_handle; | 46 return *(void**)iter->elem_handle; |
| 46 } | 47 } |
| 47 | 48 |
| 48 static void cx_iter_next_fast(void *it) { | 49 static void cx_iter_next(void *it) { |
| 49 struct cx_iterator_s *iter = it; | 50 struct cx_iterator_s *iter = it; |
| 50 if (iter->base.remove) { | 51 assert(!iter->base.remove); |
| 51 iter->base.remove = false; | 52 iter->index++; |
| 52 iter->elem_count--; | 53 iter->elem_handle = ((char *) iter->elem_handle) + iter->elem_size; |
| 53 // only move the last element when we are not currently aiming | |
| 54 // at the last element already | |
| 55 if (iter->index < iter->elem_count) { | |
| 56 void *last = ((char *) iter->src_handle) | |
| 57 + iter->elem_count * iter->elem_size; | |
| 58 memcpy(iter->elem_handle, last, iter->elem_size); | |
| 59 } | |
| 60 } else { | |
| 61 iter->index++; | |
| 62 iter->elem_handle = ((char *) iter->elem_handle) + iter->elem_size; | |
| 63 } | |
| 64 } | 54 } |
| 65 | 55 |
| 66 static void cx_iter_next_slow(void *it) { | 56 CxIterator cxIterator(const void *array, size_t elem_size, size_t elem_count) { |
| 67 struct cx_iterator_s *iter = it; | |
| 68 if (iter->base.remove) { | |
| 69 iter->base.remove = false; | |
| 70 iter->elem_count--; | |
| 71 | |
| 72 // number of elements to move | |
| 73 size_t remaining = iter->elem_count - iter->index; | |
| 74 if (remaining > 0) { | |
| 75 memmove( | |
| 76 iter->elem_handle, | |
| 77 ((char *) iter->elem_handle) + iter->elem_size, | |
| 78 remaining * iter->elem_size | |
| 79 ); | |
| 80 } | |
| 81 } else { | |
| 82 iter->index++; | |
| 83 iter->elem_handle = ((char *) iter->elem_handle) + iter->elem_size; | |
| 84 } | |
| 85 } | |
| 86 | |
| 87 CxIterator cxIterator( | |
| 88 const void *array, | |
| 89 size_t elem_size, | |
| 90 size_t elem_count, | |
| 91 bool remove_keeps_order | |
| 92 ) { | |
| 93 CxIterator iter; | 57 CxIterator iter; |
| 94 | 58 |
| 95 iter.index = 0; | 59 iter.index = 0; |
| 96 iter.src_handle = (void*) array; | 60 iter.src_handle = (void*) array; |
| 97 iter.elem_handle = (void*) array; | 61 iter.elem_handle = (void*) array; |
| 98 iter.elem_size = elem_size; | 62 iter.elem_size = elem_size; |
| 99 iter.elem_count = array == NULL ? 0 : elem_count; | 63 iter.elem_count = array == NULL ? 0 : elem_count; |
| 100 iter.base.valid = cx_iter_valid; | 64 iter.base.valid = cx_iter_valid; |
| 101 iter.base.current = cx_iter_current; | 65 iter.base.current = cx_iter_current; |
| 102 iter.base.next = remove_keeps_order ? cx_iter_next_slow : cx_iter_next_fast; | 66 iter.base.next = cx_iter_next; |
| 67 iter.base.valid_impl = NULL; | |
| 68 iter.base.current_impl = NULL; | |
| 69 iter.base.next_impl = NULL; | |
| 103 iter.base.remove = false; | 70 iter.base.remove = false; |
| 104 iter.base.allow_remove = true; | 71 iter.base.allow_remove = true; |
| 105 | 72 |
| 106 return iter; | 73 return iter; |
| 107 } | 74 } |
| 108 | 75 |
| 109 CxIterator cxIteratorPtr( | 76 CxIterator cxIteratorPtr(const void *array, size_t elem_count) { |
| 110 const void *array, | 77 CxIterator iter = cxIterator(array, sizeof(void*), elem_count); |
| 111 size_t elem_count, | |
| 112 bool remove_keeps_order | |
| 113 ) { | |
| 114 CxIterator iter = cxIterator(array, sizeof(void*), elem_count, remove_keeps_order); | |
| 115 iter.base.current = cx_iter_current_ptr; | 78 iter.base.current = cx_iter_current_ptr; |
| 116 return iter; | 79 return iter; |
| 117 } | 80 } |
