hash.c File Reference

#include <rosdhcp.h>

Include dependency graph for hash.c:

Go to the source code of this file.

Macros
#define	lint

Functions
static __inline int do_hash	PROTO ((unsigned char *, int, int))
struct hash_table *	new_hash ()
static __inline int	do_hash (unsigned char *name, int len, int size)
void	add_hash (struct hash_table *table, unsigned char *name, int len, unsigned char *pointer)
void	delete_hash_entry (struct hash_table *table, unsigned char *name, int len)
unsigned char *	hash_lookup (struct hash_table *table, unsigned char *name, int len)

Macro Definition Documentation

lint

#define lint

Definition at line 43 of file hash.c.

Function Documentation

add_hash()

void add_hash	(	struct hash_table *	table,
		unsigned char *	name,
		int	len,
		unsigned char *	pointer
	)

Definition at line 82 of file hash.c.

{
    int hashno;
    struct hash_bucket *bp;
 
    if (!table)
        return;
    if (!len)
        len = strlen ((char *)name);
 
    hashno = do_hash (name, len, table -> hash_count);
    bp = new_hash_bucket ();
 
    if (!bp) {
        warn ("Can't add %s to hash table.", name);
        return;
    }
    bp -> name = name;
    bp -> value = pointer;
    bp -> next = table -> buckets [hashno];
    bp -> len = len;
    table -> buckets [hashno] = bp;
}

Referenced by assign_file_addresses(), assign_inodes(), compute_linkcount(), and initialize_universes().

delete_hash_entry()

void delete_hash_entry	(	struct hash_table *	table,
		unsigned char *	name,
		int	len
	)

Definition at line 110 of file hash.c.

{
    int hashno;
    struct hash_bucket *bp, *pbp = (struct hash_bucket *)0;
 
    if (!table)
        return;
    if (!len)
        len = strlen ((char *)name);
 
    hashno = do_hash (name, len, table -> hash_count);
 
    /* Go through the list looking for an entry that matches;
       if we find it, delete it. */
    for (bp = table -> buckets [hashno]; bp; bp = bp -> next) {
        if ((!bp -> len &&
             !strcmp ((char *)bp -> name, (char *)name)) ||
            (bp -> len == len &&
             !memcmp (bp -> name, name, len))) {
            if (pbp) {
                pbp -> next = bp -> next;
            } else {
                table -> buckets [hashno] = bp -> next;
            }
            free_hash_bucket (bp, "delete_hash_entry");
            break;
        }
        pbp = bp;   /* jwg, 9/6/96 - nice catch! */
    }
}

do_hash()

static __inline int do_hash ( unsigned char *  name, int  len, int  size  )

static

Definition at line 63 of file hash.c.

{
    register int accum = 0;
    register unsigned char *s = name;
    int i = len;
    while (i--) {
        /* Add the character in... */
        accum += *s++;
        /* Add carry back in... */
        while (accum > 255) {
            accum = (accum & 255) + (accum >> 8);
        }
    }
    return accum % size;
}

Referenced by add_hash(), delete_hash_entry(), collate< char >::hash(), collate< wchar_t >::hash(), and hash_lookup().

hash_lookup()

unsigned char * hash_lookup	(	struct hash_table *	table,
		unsigned char *	name,
		int	len
	)

Definition at line 144 of file hash.c.

{
    int hashno;
    struct hash_bucket *bp;
 
    if (!table)
        return (unsigned char *)0;
 
    if (!len)
        len = strlen ((char *)name);
 
    hashno = do_hash (name, len, table -> hash_count);
 
    for (bp = table -> buckets [hashno]; bp; bp = bp -> next) {
        if (len == bp -> len && !memcmp (bp -> name, name, len))
            return bp -> value;
    }
    return (unsigned char *)0;
}

new_hash()

struct hash_table * new_hash

(

void

)

Definition at line 53 of file hash.c.

{
    struct hash_table *rv = new_hash_table (DEFAULT_HASH_SIZE);
    if (!rv)
        return rv;
    memset (&rv -> buckets [0], 0,
        DEFAULT_HASH_SIZE * sizeof (struct hash_bucket *));
    return rv;
}

Referenced by initialize_universes(), and test_put_hash().

PROTO()

static __inline int do_hash PROTO ( (unsigned char *, int, int)  )

static