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-rw-r--r--libgo/runtime/go-map-delete.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/libgo/runtime/go-map-delete.c b/libgo/runtime/go-map-delete.c
new file mode 100644
index 000000000..ec851e531
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+++ b/libgo/runtime/go-map-delete.c
@@ -0,0 +1,52 @@
+/* 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 "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;
+ size_t key_offset;
+ _Bool (*equalfn) (const void*, const void*, size_t);
+ size_t key_hash;
+ size_t key_size;
+ size_t bucket_index;
+ void **pentry;
+
+ 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;
+ }
+}