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30 * \brief Interface for map implementations.
32 * \author Olaf Wintermann
34 * \copyright 2-Clause BSD License
38 #ifndef UCX_HASH_KEY_H
39 #define UCX_HASH_KEY_H
47 /** Internal structure for a key within a hash map. */
48 struct cx_hash_key_s {
52 unsigned char const *cbytes;
59 * The key data length.
62 /** The hash value of the key data. */
67 * Type for a hash key.
69 typedef struct cx_hash_key_s CxHashKey;
72 * Computes a murmur2 32 bit hash.
74 * You need to initialize \c data and \c len in the key struct.
75 * The hash is then directly written to that struct.
77 * \note If \c data is \c NULL, the hash is defined as 1574210520.
79 * @param key the key, the hash shall be computed for
81 void cx_hash_murmur(CxHashKey *key);
84 * Computes a hash key from a string.
86 * The string needs to be zero-terminated.
88 * @param str the string
89 * @return the hash key
91 __attribute__((__warn_unused_result__))
92 CxHashKey cx_hash_key_str(char const *str);
95 * Computes a hash key from a byte array.
97 * @param bytes the array
98 * @param len the length
99 * @return the hash key
101 __attribute__((__warn_unused_result__))
102 CxHashKey cx_hash_key_bytes(
103 unsigned char const *bytes,
108 * Computes a hash key for an arbitrary object.
110 * The computation uses the in-memory representation that might not be
111 * the same on different platforms. Therefore, this hash should not be
112 * used for data exchange with different machines.
114 * @param obj a pointer to an arbitrary object
115 * @param len the length of object in memory
116 * @return the hash key
118 __attribute__((__warn_unused_result__))
119 CxHashKey cx_hash_key(
125 * Computes a hash key from a UCX string.
127 * @param str the string
128 * @return the hash key
130 #define cx_hash_key_cxstr(str) cx_hash_key((void*)(str).ptr, (str).length)
136 #endif // UCX_HASH_KEY_H