Subversion Repositories openrisc

/* 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;

  if (map == NULL)

    runtime_panicstring ("deletion of entry in nil map");

  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;

    }

}