ARB
gb_hashindex.h
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1 // =============================================================== //
2 // //
3 // File : gb_hashindex.h //
4 // Purpose : //
5 // //
6 // Institute of Microbiology (Technical University Munich) //
7 // http://www.arb-home.de/ //
8 // //
9 // =============================================================== //
10 
11 #ifndef GB_HASHINDEX_H
12 #define GB_HASHINDEX_H
13 
14 #ifndef GB_LOCAL_H
15 #include "gb_local.h"
16 #endif
17 
18 // -------------------------------
19 // hash index calculation
20 
21 extern const uint32_t crctab[];
22 //#define USE_DJB2_HASH
23 #define USE_ARB_CRC_HASH
24 #ifdef USE_ARB_CRC_HASH
25 
26 #define GB_CALC_HASH_INDEX_CASE_SENSITIVE(string, index, size) do { \
27  const char *local_ptr = (string); \
28  int local_i; \
29  (index) = 0xffffffffL; \
30  while ((local_i=(*(local_ptr++)))) { \
31  (index) = crctab[((int)(index)^local_i) & 0xff] ^ ((index) >> 8); \
32  } \
33  (index) = (index) % (size); \
34  } while (0)
35 
36 #define GB_CALC_HASH_INDEX_CASE_IGNORED(string, index, size) do { \
37  const char *local_ptr = (string); \
38  int local_i; \
39  (index) = 0xffffffffL; \
40  while ((local_i = *(local_ptr++))) { \
41  (index) = crctab[((int) (index) ^ toupper(local_i)) & 0xff] ^ ((index) >> 8); \
42  } \
43  (index) = (index) % (size); \
44  } while (0)
45 
46 #elif defined(USE_DJB2_HASH)
47 
48 #define GB_CALC_HASH_INDEX_CASE_SENSITIVE(string, index, size) do { \
49  const char *local_ptr = (string); \
50  (index) = 5381; \
51  int local_i; \
52  while ((local_i = *(local_ptr++))) { \
53  (index) = (((index) << 5) + (index))+ local_i; \
54  } \
55  (index) = (index) % (size); \
56  } while (0)
57 
58 #define GB_CALC_HASH_INDEX_CASE_IGNORED(string, index, size) do { \
59  const char *local_ptr = (string); \
60  int local_i; \
61  (index) = 5381; \
62  while ((local_i = *(local_ptr++))) { \
63  (index) = (((index) << 5) + (index))+ toupper(local_i); \
64  } \
65  (index) = (index) % (size); \
66  } while (0)
67 
68 #endif
69 
70 #define GB_CALC_HASH_INDEX(string, index, size, caseSens) do { \
71  if ((caseSens) == GB_IGNORE_CASE) \
72  GB_CALC_HASH_INDEX_CASE_IGNORED(string, index, size); \
73  else \
74  GB_CALC_HASH_INDEX_CASE_SENSITIVE(string, index, size); \
75  } while (0)
76 
77 
78 
79 #else
80 #error gb_hashindex.h included twice
81 #endif // GB_HASHINDEX_H
const uint32_t crctab[]
Definition: adstring.cxx:265