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2022-09-29 17:59:04 +03:00

79 lines
1.2 KiB
C

#if 0
static char sccsid[] = "@(#)table.c 1.2 90/07/24 4.1NFSSRC Copyr 1990 Sun Micro";
#endif
#include <ctype.h>
#include "util.h"
#include "table.h"
/*
* Hash table manager. Store/lookup strings, keyed by string
*/
/*
* Generate the key into the table using the first two letters
* of "str". The table is alphabetized, with no distinction between
* upper and lower case. Non-letters are given least significance.
*/
int
tablekey(str)
register char *str;
{
# define TOLOWER(c) (islower(c) ? c : \
(isupper(c) ? tolower(c) : ('a'+NUMLETTERS-1)))
register int c1,c2;
c1 = *str++;
c2 = *str;
if (c1 == EOS) {
c2 = EOS; /* just in case */
}
c1 = TOLOWER(c1) - 'a';
c2 = TOLOWER(c2) - 'a';
return (c1*NUMLETTERS + c2);
}
void
store(table,key,datum)
stringtable table;
char *key;
char *datum;
{
int index;
tablelist cur,new;
index = tablekey(key);
cur = table[index];
new = MALLOC(tablenode);
new->key = key;
new->datum = datum;
new->next = cur;
table[index] = new;
}
char *
lookup(table,key)
stringtable table;
char *key;
{
tablelist cur;
cur = table[tablekey(key)];
while (cur && strcmp(cur->key,key)) {
cur = cur->next;
}
if (cur) {
return(cur->datum);
} else {
return(NULL);
}
}