1 /* go-map-delete.c -- delete an entry from a map. 2 3 Copyright 2009 The Go Authors. All rights reserved. 4 Use of this source code is governed by a BSD-style 5 license that can be found in the LICENSE file. */ 6 7 #include <stddef.h> 8 #include <stdlib.h> 9 10 #include "runtime.h" 11 #include "malloc.h" 12 #include "go-alloc.h" 13 #include "go-assert.h" 14 #include "map.h" 15 16 /* Delete the entry matching KEY from MAP. */ 17 18 void __go_map_delete(struct __go_map * map,const void * key)19__go_map_delete (struct __go_map *map, const void *key) 20 { 21 const struct __go_map_descriptor *descriptor; 22 const struct __go_type_descriptor *key_descriptor; 23 uintptr_t key_offset; 24 const FuncVal *equalfn; 25 size_t key_hash; 26 size_t key_size; 27 size_t bucket_index; 28 void **pentry; 29 30 if (map == NULL) 31 return; 32 33 descriptor = map->__descriptor; 34 35 key_descriptor = descriptor->__map_descriptor->__key_type; 36 key_offset = descriptor->__key_offset; 37 key_size = key_descriptor->__size; 38 if (key_size == 0) 39 return; 40 41 __go_assert (key_size != -1UL); 42 equalfn = key_descriptor->__equalfn; 43 44 key_hash = __go_call_hashfn (key_descriptor->__hashfn, key, key_size); 45 bucket_index = key_hash % map->__bucket_count; 46 47 pentry = map->__buckets + bucket_index; 48 while (*pentry != NULL) 49 { 50 char *entry = (char *) *pentry; 51 if (__go_call_equalfn (equalfn, key, entry + key_offset, key_size)) 52 { 53 *pentry = *(void **) entry; 54 if (descriptor->__entry_size >= TinySize) 55 __go_free (entry); 56 map->__element_count -= 1; 57 break; 58 } 59 pentry = (void **) entry; 60 } 61 } 62