-/*
- * Copyright (C) 1994, Index Data I/S
- * All rights reserved.
- * Sebastian Hammer, Adam Dickmeiss
- *
- * $Log: delete.c,v $
- * Revision 1.2 1995-12-06 17:48:30 adam
- * Bug fix: delete didn't work.
- *
- * Revision 1.1 1995/12/06 14:52:21 adam
- * New function: dict_delete.
- *
- */
+/* This file is part of the Zebra server.
+ Copyright (C) 1994-2011 Index Data
+
+Zebra is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
-#include <dict.h>
+#include "dict-p.h"
-static int dict_del (Dict dict, const Dict_char *str)
+static void dict_del_subtree(Dict dict, Dict_ptr ptr,
+ void *client,
+ int (*f)(const char *, void *))
+{
+ void *p = 0;
+ short *indxp;
+ int i, hi;
+
+ if (!ptr)
+ return;
+
+ dict_bf_readp(dict->dbf, ptr, &p);
+ indxp = (short*) ((char*) p+DICT_bsize(p)-sizeof(short));
+ hi = DICT_nodir(p)-1;
+ for (i = 0; i <= hi; i++)
+ {
+ if (indxp[-i] > 0)
+ {
+ /* string (Dict_char *) DICT_EOS terminated */
+ /* unsigned char length of information */
+ /* char * information */
+ char *info = (char*)p + indxp[-i];
+ if (f)
+ (*f)(info + (dict_strlen((Dict_char*) info)+1)
+ *sizeof(Dict_char), client);
+ }
+ else
+ {
+ Dict_ptr subptr;
+
+ /* Dict_ptr subptr */
+ /* Dict_char sub char */
+ /* unsigned char length of information */
+ /* char * information */
+ char *info = (char*)p - indxp[-i];
+ memcpy(&subptr, info, sizeof(Dict_ptr));
+
+ if (info[sizeof(Dict_ptr)+sizeof(Dict_char)])
+ {
+ if (f)
+ (*f)(info+sizeof(Dict_ptr)+sizeof(Dict_char), client);
+ }
+ if (subptr)
+ {
+ dict_del_subtree(dict, subptr, client, f);
+
+ /* page may be gone. reread it .. */
+ dict_bf_readp(dict->dbf, ptr, &p);
+ indxp = (short*) ((char*) p+DICT_bsize(p)-sizeof(short));
+ }
+ }
+ }
+ DICT_backptr(p) = dict->head.freelist;
+ dict->head.freelist = ptr;
+ dict_bf_touch(dict->dbf, ptr);
+}
+
+static int dict_del_string(Dict dict, const Dict_char *str, Dict_ptr ptr,
+ int sub_flag, void *client,
+ int (*f)(const char *, void *))
{
- Dict_ptr ptr = 1;
int mid, lo, hi;
int cmp;
void *p;
short *indxp;
char *info;
+ int r = 0;
+ Dict_ptr subptr = 0;
- dict_bf_readp (dict->dbf, ptr, &p);
+ if (!ptr)
+ return 0;
+ dict_bf_readp(dict->dbf, ptr, &p);
mid = lo = 0;
hi = DICT_nodir(p)-1;
- indxp = (short*) ((char*) p+DICT_pagesize(dict)-sizeof(short));
+ indxp = (short*) ((char*) p+DICT_bsize(p)-sizeof(short));
while (lo <= hi)
{
mid = (lo+hi)/2;
/* unsigned char length of information */
/* char * information */
info = (char*)p + indxp[-mid];
- cmp = dict_strcmp((Dict_char*) info, str);
- if (!cmp)
- {
- hi = DICT_nodir(p)-1;
- while (mid < hi)
- {
- indxp[-mid] = indxp[-mid-1];
- mid++;
- }
- (DICT_nodir(p))--;
- dict_bf_touch (dict->dbf, ptr);
- return 1;
- }
+
+ cmp = dict_strcmp((Dict_char*) info, str);
+ if (sub_flag)
+ {
+ /* determine if prefix match */
+ if (!dict_strncmp(str, (Dict_char*) info, dict_strlen(str)))
+ {
+ if (f)
+ (*f)(info + (dict_strlen((Dict_char*) info)+1)
+ *sizeof(Dict_char), client);
+
+ hi = DICT_nodir(p)-1;
+ while (mid < hi)
+ {
+ indxp[-mid] = indxp[-mid-1];
+ mid++;
+ }
+ DICT_type(p) = 1;
+ (DICT_nodir(p))--;
+ dict_bf_touch(dict->dbf, ptr);
+ --hi;
+ mid = lo = 0;
+ r = 1; /* signal deleted */
+ /* start again (may not be the most efficient way to go)*/
+ continue;
+ }
+ }
+ else
+ {
+ /* normal delete: delete if equal */
+ if (!cmp)
+ {
+ hi = DICT_nodir(p)-1;
+ while (mid < hi)
+ {
+ indxp[-mid] = indxp[-mid-1];
+ mid++;
+ }
+ DICT_type(p) = 1;
+ (DICT_nodir(p))--;
+ dict_bf_touch(dict->dbf, ptr);
+ r = 1;
+ break;
+ }
+ }
}
else
{
Dict_char dc;
- Dict_ptr subptr;
/* Dict_ptr subptr */
/* Dict_char sub char */
/* unsigned char length of information */
/* char * information */
info = (char*)p - indxp[-mid];
- memcpy (&dc, info+sizeof(Dict_ptr), sizeof(Dict_char));
+ memcpy(&dc, info+sizeof(Dict_ptr), sizeof(Dict_char));
cmp = dc- *str;
if (!cmp)
{
- memcpy (&subptr, info, sizeof(Dict_ptr));
+ memcpy(&subptr, info, sizeof(Dict_ptr));
if (*++str == DICT_EOS)
{
if (info[sizeof(Dict_ptr)+sizeof(Dict_char)])
{
+ /* entry does exist. Wipe it out */
info[sizeof(Dict_ptr)+sizeof(Dict_char)] = 0;
- dict_bf_touch (dict->dbf, ptr);
- return 1;
+ DICT_type(p) = 1;
+ dict_bf_touch(dict->dbf, ptr);
+
+ if (f)
+ (*f)(info+sizeof(Dict_ptr)+sizeof(Dict_char),
+ client);
+ r = 1;
}
- return 0;
+ if (sub_flag)
+ {
+ /* must delete all suffixes (subtrees) as well */
+ hi = DICT_nodir(p)-1;
+ while (mid < hi)
+ {
+ indxp[-mid] = indxp[-mid-1];
+ mid++;
+ }
+ (DICT_nodir(p))--;
+ DICT_type(p) = 1;
+ dict_bf_touch(dict->dbf, ptr);
+ }
}
else
{
- if (subptr == 0)
- return 0;
- ptr = subptr;
- dict_bf_readp (dict->dbf, ptr, &p);
- mid = lo = 0;
- hi = DICT_nodir(p)-1;
- indxp = (short*) ((char*) p+DICT_pagesize(dict)
- -sizeof(short));
- continue;
+ /* subptr may be 0 */
+ r = dict_del_string(dict, str, subptr, sub_flag, client, f);
+
+ /* recover */
+ dict_bf_readp(dict->dbf, ptr, &p);
+ indxp = (short*)
+ ((char*) p+DICT_bsize(p)-sizeof(short));
+ info = (char*)p - indxp[-mid];
+
+ subptr = 0; /* avoid dict_del_subtree (end of function)*/
+ if (r == 2)
+ { /* subptr page became empty and is removed */
+
+ /* see if this entry is a real one or if it just
+ serves as pointer to subptr */
+ if (info[sizeof(Dict_ptr)+sizeof(Dict_char)])
+ {
+ /* this entry do exist, set subptr to 0 */
+ memcpy(info, &subptr, sizeof(subptr));
+ }
+ else
+ {
+ /* this entry ONLY points to subptr. remove it */
+ hi = DICT_nodir(p)-1;
+ while (mid < hi)
+ {
+ indxp[-mid] = indxp[-mid-1];
+ mid++;
+ }
+ (DICT_nodir(p))--;
+ }
+ dict_bf_touch(dict->dbf, ptr);
+ r = 1;
+ }
}
+ break;
}
}
if (cmp < 0)
else
hi = mid-1;
}
- return 0;
+ if (DICT_nodir(p) == 0 && ptr != dict->head.root)
+ {
+ DICT_backptr(p) = dict->head.freelist;
+ dict->head.freelist = ptr;
+ dict_bf_touch(dict->dbf, ptr);
+ r = 2;
+ }
+ if (subptr && sub_flag)
+ dict_del_subtree(dict, subptr, client, f);
+
+ return r;
+}
+
+int dict_delete(Dict dict, const char *p)
+{
+ return dict_del_string(dict, (const Dict_char*) p, dict->head.root, 0,
+ 0, 0);
}
-int dict_delete (Dict dict, const Dict_char *p)
+int dict_delete_subtree(Dict dict, const char *p, void *client,
+ int (*f)(const char *info, void *client))
{
- if (dict->head.last == 1)
- return 0;
- return dict_del (dict, p);
+ return dict_del_string(dict, (const Dict_char*) p, dict->head.root, 1,
+ client, f);
}
+/*
+ * Local variables:
+ * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
+ * indent-tabs-mode: nil
+ * End:
+ * vim: shiftwidth=4 tabstop=8 expandtab
+ */
+