1 files changed, 60 insertions, 0 deletions
diff --git a/external/hash/ptr_set.c b/external/hash/ptr_set.c
new file mode 100644
index 0000000..ab12ddf
--- /dev/null
+++ b/external/hash/ptr_set.c
@@ -0,0 +1,60 @@
+/*
+ * Creates a set of stored pointers by using the pointer itself as key.
+ *
+ * (void *)0 (HT_MISSING) cannot be stored.
+ * (void *)1 (HT_DELETED) also cannot be stored.
+ *
+ * ht_item, ht_key, ht_key_len, and ht_match are required.
+ *
+ * In this case HT_HASH_FUNCTION is also required because
+ * we do not read the content of the key but use the pointer
+ * itself as a key. The default behavior would crash.
+ *
+ * Only one hash table can be defined in a single compilation unit
+ * because of static function names in the generic implementation.
+ */
+
+#include "ptr_set.h"
+
+static inline size_t ptr_set_hash_function(const void *s, size_t len);
+#define HT_HASH_FUNCTION ptr_set_hash_function
+
+#define HT_LOAD_FACTOR 0.7
+#include "hash_table_def.h"
+DEFINE_HASH_TABLE(ptr_set)
+
+#if defined(PTR_SET_RH)
+#include "hash_table_impl_rh.h"
+#else
+#include "hash_table_impl.h"
+#endif
+
+static inline const void *ht_key(ht_item_t x)
+{
+    return (const void *)x;
+}
+
+static inline size_t ht_key_len(ht_item_t x)
+{
+    return sizeof(x);
+}
+
+static inline int ht_match(const void *key, size_t len, ht_item_t x)
+{
+    (void)len;
+    return (size_t)key == (size_t)x;
+}
+
+static inline size_t ptr_set_hash_function(const void *s, size_t len)
+{
+#if defined (PTR_SET_PTR_HASH)
+    /* Murmur hash like finalization step. */
+    return ht_ptr_hash_function(s, len);
+#elif defined (PTR_SET_INT_HASH)
+    /* Knuths multiplication. */
+    return ht_int_hash_function(s, len);
+#else
+    (void)len;
+    return ht_default_hash_function(&s, sizeof(char *));
+#endif
+}