![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to comp_hash.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [MW Coherent from dump] / coherent / g / usr / lib / ncurses|
Return to comp_hash.c CVS log | Up to [MW Coherent from dump] / coherent / g / usr / lib / ncurses |
1.1 root 1: /*********************************************************************
2: * COPYRIGHT NOTICE *
3: **********************************************************************
4: * This software is copyright (C) 1982 by Pavel Curtis *
5: * *
6: * Permission is granted to reproduce and distribute *
7: * this file by any means so long as no fee is charged *
8: * above a nominal handling fee and so long as this *
9: * notice is always included in the copies. *
10: * *
11: * Other rights are reserved except as explicitly granted *
12: * by written permission of the author. *
13: * Pavel Curtis *
14: * Computer Science Dept. *
15: * 405 Upson Hall *
16: * Cornell University *
17: * Ithaca, NY 14853 *
18: * *
19: * Ph- (607) 256-4934 *
20: * *
21: * Pavel.Cornell@Udel-Relay (ARPAnet) *
22: * decvax!cornell!pavel (UUCPnet) *
23: *********************************************************************/
24:
25: /*
26: * comp_hash.c --- Routines to deal with the hashtable of capability
27: * names.
28: *
29: * $Log: comp_hash.c,v $
30: * Revision 1.8 93/04/12 14:12:58 bin
31: * Udo: third color update
32: *
33: * Revision 1.2 92/04/13 14:36:14 bin
34: * update by vlad
35: *
36: * Revision 2.1 82/10/25 14:45:34 pavel
37: * Added Copyright Notice
38: *
39: * Revision 2.0 82/10/24 15:16:34 pavel
40: * Beta-one Test Release
41: *
42: * Revision 1.3 82/08/23 22:29:33 pavel
43: * The REAL Alpha-one Release Version
44: *
45: * Revision 1.2 82/08/19 19:09:46 pavel
46: * Alpha Test Release One
47: *
48: * Revision 1.1 82/08/12 18:36:23 pavel
49: * Initial revision
50: *
51: *
52: */
53:
54: #ifdef RCSHDR
55: static char RCSid[] =
56: "$Header: /src386/usr/lib/ncurses/RCS/comp_hash.c,v 1.8 93/04/12 14:12:58 bin Exp Locker: bin $";
57: #endif
58:
59: #include "compiler.h"
60: #include "term.h"
61:
62:
63: /*
64: * make_hash_table()
65: *
66: * Takes the entries in cap_table[] and hashes them into cap_hash_table[]
67: * by name. There are Captabsize entries in cap_table[] and Hashtabsize
68: * slots in cap_hash_table[].
69: *
70: */
71:
72: make_hash_table()
73: {
74: int i;
75: int hashvalue;
76: int collisions = 0;
77:
78: for (i=0; i < Captabsize; i++)
79: {
80: hashvalue = hash_function(cap_table[i].nte_name);
81: DEBUG(9, "%d\n", hashvalue);
82:
83: if (cap_hash_table[hashvalue] != (struct name_table_entry *) 0)
84: collisions++;
85:
86: cap_table[i].nte_link = cap_hash_table[hashvalue];
87: cap_hash_table[hashvalue] = &cap_table[i];
88: }
89:
90: DEBUG(3, "Hash table complete\n%d collisions ", collisions);
91: DEBUG(3, "out of %d entries\n", Captabsize);
92: }
93:
94:
95: /*
96: * int hash_function(string)
97: *
98: * Computes the hashing function on the given string.
99: *
100: * The current hash function is the sum of each consectutive pair
101: * of characters, taken as two-byte integers, mod Hashtabsize.
102: *
103: */
104:
105: static
106: int
107: hash_function(string)
108: char *string;
109: {
110: long sum = 0;
111:
112: while (*string)
113: {
114: sum += *string + (*(string + 1) << 8);
115: string++;
116: }
117:
118: return (sum % Hashtabsize);
119: }
120:
121:
122: /*
123: * struct name_table_entry *
124: * find_entry(string)
125: *
126: * Finds the entry for the given string in the hash table if present.
127: * Returns a pointer to the entry in the table or 0 if not found.
128: *
129: */
130:
131: struct name_table_entry *
132: find_entry(string)
133: char *string;
134: {
135: int hashvalue;
136: struct name_table_entry *ptr;
137:
138: hashvalue = hash_function(string);
139:
140: ptr = cap_hash_table[hashvalue];
141:
142: while (ptr != (struct name_table_entry *) 0 &&
143: strcmp(ptr->nte_name, string) != 0)
144: ptr = ptr->nte_link;
145:
146: return (ptr);
147: }
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.