\documentclass{article}
\usepackage{axiom}
\begin{document}
\title{\$SPAD/src/hash}
\author{The Axiom Team}
\maketitle
\begin{abstract}
\end{abstract}
\eject
\tableofcontents
\eject
\section{hash.c}
<<hash.c>>=
#define _HASH_C
#include "axiom-c-macros.h"
#include "useproto.h"
#include "debug.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "hash.h"

#include "hash.H1"
#include "halloc.H1"

/* initialize a hash table */

void
hash_init(HashTable *table, int size, EqualFunction equal,
          HashcodeFunction hash_code)
{
    int i;

    table->table =
        (HashEntry **) halloc(size * sizeof(HashEntry *), "HashEntry");
    for (i = 0; i < size; i++)
        table->table[i] = NULL;
    table->size = size;
    table->equal = equal;
    table->hash_code = hash_code;
    table->num_entries = 0;
}

void
free_hash(HashTable *table, FreeFunction free_fun)
{
  if (table) {
    int i;

    for (i = 0; i < table->size; i++) {
      HashEntry *e, *next;

      for (e = table->table[i]; e != NULL;) {
        next = e->next;
        (*free_fun) (e->data);
	(*e).data=0;
        free(e);
        e = next;
      }
    }
    free(table->table);
  }
}

/* insert an entry into a hash table */

void
hash_insert(HashTable *table, char *data, char *key)
{
    HashEntry *entry = (HashEntry *) halloc(sizeof(HashEntry), "HashEntry");
    int code;

    entry->data = data;
    entry->key = key;
    code = (*table->hash_code) (key, table->size) % table->size;
#ifdef DEBUG
    fprintf(stderr, "Hash value = %d\n", code);
#endif
    entry->next = table->table[code];
    table->table[code] = entry;
    table->num_entries++;
}

char *
hash_find(HashTable *table, char *key)
{
    HashEntry *entry;
    int code = table->hash_code(key, table->size) % table->size;

    for (entry = table->table[code]; entry != NULL; entry = entry->next)
        if ((*table->equal) (entry->key, key))
            return entry->data;
    return NULL;
}

char *
hash_replace(HashTable *table, char *data, char *key)
{
    HashEntry *entry;
    int code = table->hash_code(key, table->size) % table->size;

    for (entry = table->table[code]; entry != NULL; entry = entry->next)
        if ((*table->equal) (entry->key, key)) {
            entry->data = data;
            return entry->data;
        }
    return NULL;
}

void
hash_delete(HashTable *table, char *key)
{
    HashEntry **entry;
    int code = table->hash_code(key, table->size) % table->size;

    for (entry = &table->table[code]; *entry != NULL; entry = &((*entry)->next))
        if ((*table->equal) ((*entry)->key, key)) {
            *entry = (*entry)->next;
            table->num_entries--;
            return;
        }
}

void
hash_map(HashTable *table, MappableFunction func)
{
    int i;
    HashEntry *e;

    if (table == NULL)
        return;
    for (i = 0; i < table->size; i++)
        for (e = table->table[i]; e != NULL; e = e->next)
            (*func) (e->data);
}

HashEntry *
hash_copy_entry(HashEntry *e)
{
    HashEntry *ne;

    if (e == NULL)
        return e;
    ne = (HashEntry *) halloc(sizeof(HashEntry), "HashEntry");
    ne->data = e->data;
    ne->key = e->key;
    ne->next = hash_copy_entry(e->next);
    return ne;
}

/* copy a hash table */
HashTable *
hash_copy_table(HashTable *table)
{
    HashTable *nt = (HashTable *) halloc(sizeof(HashTable), "copy hash table");
    int i;

    nt->size = table->size;
    nt->num_entries = table->num_entries;
    nt->equal = table->equal;
    nt->hash_code = table->hash_code;
    nt->table = (HashEntry **) halloc(nt->size * sizeof(HashEntry *),
                                      "copy table");
    for (i = 0; i < table->size; i++)
        nt->table[i] = hash_copy_entry(table->table[i]);
    return nt;
}

/* hash code function for strings */
int
string_hash(char *s, int size)
{
    int c = 0;
    char *p =s;


    while (*p)
        c += *p++;
    return c % size;
}

/* test strings for equality */

int
string_equal(char *s1, char *s2)
{
    return (strcmp(s1, s2) == 0);
}

/* make a fresh copy of the given string */
char *
alloc_string(char *str)
{
    char * result;
    result = halloc(strlen(str)+1,"String");
    strcpy(result,str);
    return (result);
}
@
\section{License}
<<license>>=
/*
Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

    - Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

    - Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in
      the documentation and/or other materials provided with the
      distribution.

    - Neither the name of The Numerical ALgorithms Group Ltd. nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

@
<<*>>=
<<license>>
<<hash.c>>
@ 
\eject
\begin{thebibliography}{99}
\bibitem{1} nothing
\end{thebibliography}
\end{document}