nasm/nasmlib/strlist.c
H. Peter Anvin (Intel) f7106d06e4 strlist: use a hash table
Use a hash table to enforce uniqueness in a string list. It is still
an ordered list, however, and can be walked in insertion order.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
2018-10-25 12:33:58 -07:00

94 lines
2.7 KiB
C

/* ----------------------------------------------------------------------- *
*
* Copyright 1996-2018 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* 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.
*
* 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.
*
* ----------------------------------------------------------------------- */
/*
* strlist.c - list of unique, ordered strings
*/
#include "strlist.h"
/*
* Create a string list
*/
StrList *strlist_allocate(void)
{
StrList *list;
nasm_new(list);
hash_init(&list->hash, HASH_MEDIUM);
list->tailp = &list->head;
return list;
}
/*
* Append a string to a string list if and only if it isn't
* already there. Return true if it was added.
*/
bool strlist_add_string(StrList *list, const char *str)
{
struct hash_insert hi;
struct strlist_entry *sl;
size_t l;
if (!list)
return false;
if (hash_find(&list->hash, str, &hi))
return false; /* Already present */
l = strlen(str);
sl = nasm_malloc(sizeof(struct strlist_entry) + l);
sl->len = l;
memcpy(sl->str, str, l+1);
sl->next = NULL;
*list->tailp = sl;
list->tailp = &sl->next;
hash_add(&hi, sl->str, (void *)sl);
return true;
}
/*
* Free a string list
*/
void strlist_free(StrList *list)
{
if (!list)
return;
hash_free_all(&list->hash, false);
nasm_free(list);
}