util/hash_table: add helper to remove entry by key

And the corresponding test case.

Reviewed-by: Eric Anholt <eric@anholt.net>

src/util/hash_table.c

@@ -420,6 +420,15 @@ _mesa_hash_table_remove(struct hash_table *ht,
    ht->deleted_entries++;
 }
 
+/**
+ * Removes the entry with the corresponding key, if exists.
+ */
+void _mesa_hash_table_remove_key(struct hash_table *ht,
+                                 const void *key)
+{
+   _mesa_hash_table_remove(ht, _mesa_hash_table_search(ht, key));
+}
+
 /**
  * This function is an iterator over the hash table.
  *

src/util/hash_table.h

@@ -88,6 +88,8 @@ _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
                                   const void *key);
 void _mesa_hash_table_remove(struct hash_table *ht,
                              struct hash_entry *entry);
+void _mesa_hash_table_remove_key(struct hash_table *ht,
+                                 const void *key);
 
 struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
                                                struct hash_entry *entry);

src/util/tests/hash_table/.gitignore

@@ -6,6 +6,7 @@ insert_and_lookup
 insert_many
 null_destroy
 random_entry
+remove_key
 remove_null
 replacement
 clear

src/util/tests/hash_table/Makefile.am

@@ -38,6 +38,7 @@ TESTS = \
 	insert_many \
 	null_destroy \
 	random_entry \
+	remove_key \
 	remove_null \
 	replacement \
 	$()

src/util/tests/hash_table/meson.build

@@ -20,7 +20,8 @@
 
 foreach t : ['clear', 'collision', 'delete_and_lookup', 'delete_management',
              'destroy_callback', 'insert_and_lookup', 'insert_many',
-             'null_destroy', 'random_entry', 'remove_null', 'replacement']
+             'null_destroy', 'random_entry', 'remove_key', 'remove_null',
+             'replacement']
   test(
     t,
     executable(

src/util/tests/hash_table/remove_key.c

@@ -0,0 +1,63 @@
+/*
+ * Copyright © 2018 Intel Corporation
+ *
+ * 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 (including the next
+ * paragraph) 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 <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include "hash_table.h"
+
+int
+main(int argc, char **argv)
+{
+   struct hash_table *ht;
+   const char *str1 = "test1";
+   const char *str2 = "test2";
+   struct hash_entry *entry;
+
+   (void) argc;
+   (void) argv;
+
+   ht = _mesa_hash_table_create(NULL, _mesa_key_hash_string, _mesa_key_string_equal);
+
+   _mesa_hash_table_insert(ht, str1, NULL);
+   _mesa_hash_table_insert(ht, str2, NULL);
+
+   entry = _mesa_hash_table_search(ht, str2);
+   assert(strcmp(entry->key, str2) == 0);
+
+   entry = _mesa_hash_table_search(ht, str1);
+   assert(strcmp(entry->key, str1) == 0);
+
+   _mesa_hash_table_remove_key(ht, str1);
+
+   entry = _mesa_hash_table_search(ht, str1);
+   assert(entry == NULL);
+
+   entry = _mesa_hash_table_search(ht, str2);
+   assert(strcmp(entry->key, str2) == 0);
+
+   _mesa_hash_table_destroy(ht, NULL);
+
+   return 0;
+}