gcc/libgo/runtime/go-map-delete.c

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/* go-map-delete.c -- delete an entry from a map.
Copyright 2009 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include <stddef.h>
#include <stdlib.h>
#include "runtime.h"
#include "go-alloc.h"
#include "go-assert.h"
#include "map.h"
/* Delete the entry matching KEY from MAP. */
void
__go_map_delete (struct __go_map *map, const void *key)
{
const struct __go_map_descriptor *descriptor;
const struct __go_type_descriptor *key_descriptor;
uintptr_t key_offset;
_Bool (*equalfn) (const void*, const void*, uintptr_t);
size_t key_hash;
size_t key_size;
size_t bucket_index;
void **pentry;
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if (map == NULL)
return;
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descriptor = map->__descriptor;
key_descriptor = descriptor->__map_descriptor->__key_type;
key_offset = descriptor->__key_offset;
key_size = key_descriptor->__size;
__go_assert (key_size != 0 && key_size != -1UL);
equalfn = key_descriptor->__equalfn;
key_hash = key_descriptor->__hashfn (key, key_size);
bucket_index = key_hash % map->__bucket_count;
pentry = map->__buckets + bucket_index;
while (*pentry != NULL)
{
char *entry = (char *) *pentry;
if (equalfn (key, entry + key_offset, key_size))
{
*pentry = *(void **) entry;
__go_free (entry);
map->__element_count -= 1;
break;
}
pentry = (void **) entry;
}
}