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+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef included_clib_mhash_h
+#define included_clib_mhash_h
+
+/*
+ Copyright (c) 2010 Eliot Dresselhaus
+
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include <vppinfra/format.h>
+#include <vppinfra/hash.h>
+#include <vppinfra/heap.h>
+
+/* Hash table plus vector of keys. */
+typedef struct
+{
+ /* Vector or heap used to store keys. Hash table stores keys as byte
+ offsets into this vector. */
+ u8 *key_vector_or_heap;
+
+ /* Byte offsets of free keys in vector (used to store free keys when
+ n_key_bytes > 1). */
+ u32 *key_vector_free_indices;
+
+ u8 **key_tmps;
+
+ /* Possibly fixed size of key.
+ 0 means keys are vectors of u8's.
+ 1 means keys are null terminated c strings. */
+#define MHASH_VEC_STRING_KEY 0
+#define MHASH_C_STRING_KEY 1
+ u32 n_key_bytes;
+
+ /* Seed value for Jenkins hash. */
+ u32 hash_seed;
+
+ /* Hash table mapping key -> value. */
+ uword *hash;
+
+ /* Format function for keys. */
+ format_function_t *format_key;
+} mhash_t;
+
+void mhash_init (mhash_t * h, uword n_value_bytes, uword n_key_bytes);
+
+always_inline void
+mhash_init_c_string (mhash_t * h, uword n_value_bytes)
+{
+ mhash_init (h, n_value_bytes, MHASH_C_STRING_KEY);
+}
+
+always_inline void
+mhash_init_vec_string (mhash_t * h, uword n_value_bytes)
+{
+ mhash_init (h, n_value_bytes, MHASH_VEC_STRING_KEY);
+}
+
+always_inline void *
+mhash_key_to_mem (mhash_t * h, uword key)
+{
+ if (key == ~0)
+ {
+ u8 *key_tmp;
+
+ int my_cpu = os_get_thread_index ();
+ vec_validate (h->key_tmps, my_cpu);
+ key_tmp = h->key_tmps[my_cpu];
+ return key_tmp;
+ }
+ return vec_elt_at_index (h->key_vector_or_heap, key);
+}
+
+hash_pair_t *mhash_get_pair (mhash_t * h, const void *key);
+uword mhash_set_mem (mhash_t * h, void *key, uword * new_value,
+ uword * old_value);
+uword mhash_unset (mhash_t * h, void *key, uword * old_value);
+
+always_inline uword *
+mhash_get (mhash_t * h, const void *key)
+{
+ hash_pair_t *p = mhash_get_pair (h, key);
+ return p ? &p->value[0] : 0;
+}
+
+always_inline uword
+mhash_set (mhash_t * h, void *key, uword new_value, uword * old_value)
+{
+ return mhash_set_mem (h, key, &new_value, old_value);
+}
+
+always_inline uword
+mhash_unset_key (mhash_t * h, uword key, uword * old_value)
+{
+ void *k = mhash_key_to_mem (h, key);
+ return mhash_unset (h, k, old_value);
+}
+
+always_inline uword
+mhash_value_bytes (mhash_t * m)
+{
+ hash_t *h = hash_header (m->hash);
+ return hash_value_bytes (h);
+}
+
+always_inline uword
+mhash_elts (mhash_t * m)
+{
+ return hash_elts (m->hash);
+}
+
+always_inline uword
+mhash_key_vector_is_heap (mhash_t * h)
+{
+ return h->n_key_bytes <= 1;
+}
+
+always_inline void
+mhash_free (mhash_t * h)
+{
+ if (mhash_key_vector_is_heap (h))
+ heap_free (h->key_vector_or_heap);
+ else
+ vec_free (h->key_vector_or_heap);
+ vec_free (h->key_vector_free_indices);
+ hash_free (h->hash);
+}
+
+#define mhash_foreach(k,v,mh,body) \
+do { \
+ hash_pair_t * _mhash_foreach_p; \
+ hash_foreach_pair (_mhash_foreach_p, (mh)->hash, ({ \
+ (k) = mhash_key_to_mem ((mh), _mhash_foreach_p->key); \
+ (v) = &_mhash_foreach_p->value[0]; \
+ body; \
+ })); \
+} while (0)
+
+format_function_t format_mhash_key;
+
+#endif /* included_clib_mhash_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */