No longer need this system since it was only being used in the DNS caching
section and the anonymous header section. Once I had removed the DNS caching, the ternary tree system was overkill for the anonymous header code. Replaced in the anonymous header section with a simple linked list.
This commit is contained in:
Robert James Kaes
parent
b969ed4302
commit
997d3daa65
404
src/ternary.c
404
src/ternary.c
@ -1,404 +0,0 @@
|
|||||||
/* $Id: ternary.c,v 1.12 2001-11-22 00:31:10 rjkaes Exp $
|
|
||||||
*
|
|
||||||
* This module creates a Ternary Search Tree which can store both string
|
|
||||||
* keys, and arbitrary data for each key. It works similar to a hash, and
|
|
||||||
* a binary search tree. The idea (and some code) is taken from Dr. Dobb's
|
|
||||||
* Journal, April 1998 "Ternary Search Trees", Jon Bentley and Bob
|
|
||||||
* Sedgewick, pg 20-25. The supplied code was then made "production" ready.
|
|
||||||
* Hopefully, the comments in the code should make the API self
|
|
||||||
* explanatory.
|
|
||||||
*
|
|
||||||
* Copyright (C) 2000 Robert James Kaes (rjkaes@flarenet.com)
|
|
||||||
*
|
|
||||||
* This program 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.
|
|
||||||
*
|
|
||||||
* This program 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.
|
|
||||||
*/
|
|
||||||
|
|
||||||
#include "tinyproxy.h"
|
|
||||||
|
|
||||||
#include "log.h"
|
|
||||||
#include "ternary.h"
|
|
||||||
#include "utils.h"
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Macros for the tree structures (limits)
|
|
||||||
*/
|
|
||||||
#define MAXTREES 128 /* max. number of trees */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* The structure for each individual node of the ternary tree.
|
|
||||||
*/
|
|
||||||
typedef struct tnode {
|
|
||||||
char splitchar;
|
|
||||||
struct tnode *lokid, *eqkid, *hikid;
|
|
||||||
} Tnode;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* The structure for each root of a ternary tree.
|
|
||||||
*/
|
|
||||||
#define BUFSIZE 512
|
|
||||||
#define BUFARRAY 512
|
|
||||||
typedef struct ttree {
|
|
||||||
TERNARY token; /* contains unique ternary tree ID */
|
|
||||||
Tnode *tree_root;
|
|
||||||
Tnode *buf;
|
|
||||||
int bufn, freen;
|
|
||||||
Tnode *freearr[BUFARRAY];
|
|
||||||
} Ttree;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* variables shared by library routines.
|
|
||||||
*/
|
|
||||||
static Ttree *trees[MAXTREES]; /* the array of trees */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* nonce generator -- this MUST be non-zero _always_
|
|
||||||
*/
|
|
||||||
#define IOFFSET 0x1221 /* used to hide index number in token */
|
|
||||||
#define NOFFSET 0x0502 /* initial nonce */
|
|
||||||
static unsigned int noncectr = NOFFSET;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Contains any error messages from the functions.
|
|
||||||
*/
|
|
||||||
char te_errbuf[256];
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Generate a token; this is an integer: index number + OFFSET,,none
|
|
||||||
* WARNING: Each quantity must fix into 16 bits
|
|
||||||
*
|
|
||||||
* Parameters: int index index number
|
|
||||||
* Returned: TERNARY token of corresponding tree
|
|
||||||
* Errors: TE_INTINCON * index + OFFSET is too big
|
|
||||||
* * nonce is too big
|
|
||||||
* * index is out of range
|
|
||||||
* (te_errbuf has disambiguating string)
|
|
||||||
* Exceptions: none
|
|
||||||
*/
|
|
||||||
static TERNARY
|
|
||||||
create_token_ref(unsigned int ind)
|
|
||||||
{
|
|
||||||
unsigned int high; /* high 16 bits of token (index) */
|
|
||||||
unsigned int low; /* low 16 bits of token (nonce) */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Sanity check argument; called internally...
|
|
||||||
*/
|
|
||||||
if (ind > MAXTREES) {
|
|
||||||
ERRBUF3("create_token_ref: index %u exceeds %d", ind, MAXTREES);
|
|
||||||
return TE_INTINCON;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Get the high part of the token (index into tree array, offset by
|
|
||||||
* some arbitrary amount)
|
|
||||||
* SANITY CHECK: Be sure index + OFFSET fits into 16 bits as positive.
|
|
||||||
*/
|
|
||||||
high = (ind + IOFFSET) & 0x7fff;
|
|
||||||
if (high != ind + IOFFSET) {
|
|
||||||
ERRBUF3("create_token_ref: index %u larger than %u", ind,
|
|
||||||
0x7fff - IOFFSET);
|
|
||||||
return TE_INTINCON;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Get the low part of the token (nonce)
|
|
||||||
* SANITY CHECK: Be sure nonce fits into 16 bits
|
|
||||||
*/
|
|
||||||
low = noncectr & 0xffff;
|
|
||||||
if ((low != noncectr++) || low == 0) {
|
|
||||||
ERRBUF3("create_token_ref: generation number %u exceeds %u",
|
|
||||||
noncectr - 1, 0xffff - NOFFSET);
|
|
||||||
return TE_INTINCON;
|
|
||||||
}
|
|
||||||
|
|
||||||
return (TERNARY) ((high << 16) | low);
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check a token number and turn it into an index.
|
|
||||||
*
|
|
||||||
* Parameters: TERNARY tno ternary token from the user
|
|
||||||
* Returned: int index from the ticket
|
|
||||||
* Errors: TE_BADTOKEN ternary token is invalid because:
|
|
||||||
* * index out of range [0 .. MAXTREES]
|
|
||||||
* * index is for unused slot
|
|
||||||
* * nonce is of old tree
|
|
||||||
* (te_errbuf has disambiguating string)
|
|
||||||
* TE_INTINCON tree is internally inconsistent because:
|
|
||||||
* * nonce is 0
|
|
||||||
* (te_errbuf has disambiguating string)
|
|
||||||
* EXCEPTIONS: none
|
|
||||||
*/
|
|
||||||
static int
|
|
||||||
read_token_ref(TERNARY tno)
|
|
||||||
{
|
|
||||||
unsigned int ind; /* index of current tree */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Get the index number and check it for validity
|
|
||||||
*/
|
|
||||||
ind = ((tno >> 16) & 0xffff) - IOFFSET;
|
|
||||||
if (ind >= MAXTREES) {
|
|
||||||
ERRBUF3("read_token_ref: index %u exceeds %d", ind, MAXTREES);
|
|
||||||
return TE_BADTOKEN;
|
|
||||||
}
|
|
||||||
if (trees[ind] == NULL) {
|
|
||||||
ERRBUF2("readbuf: token refers to unused tree index %u", ind);
|
|
||||||
return TE_BADTOKEN;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* We have a valid index; now validate the nonce; note we store the
|
|
||||||
* token in the tree, so just check that (same thing)
|
|
||||||
*/
|
|
||||||
if (trees[ind]->token != tno) {
|
|
||||||
ERRBUF3("readbuf: token refers to old tree (new=%u, old=%u)",
|
|
||||||
(unsigned int) ((trees[ind]->token) & 0xffff) - IOFFSET,
|
|
||||||
(unsigned int) (tno & 0xffff) - NOFFSET);
|
|
||||||
return TE_BADTOKEN;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check for internal consistencies
|
|
||||||
*/
|
|
||||||
if ((trees[ind]->token & 0xffff) == 0) {
|
|
||||||
ERRBUF("read_token_ref: internal inconsistency: nonce = 0");
|
|
||||||
return TE_INTINCON;
|
|
||||||
}
|
|
||||||
|
|
||||||
return ind;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Create a new tree
|
|
||||||
*
|
|
||||||
* Parameters: none
|
|
||||||
* Returned: TERNARY token (if > 0); error number (if < 0)
|
|
||||||
* Errors: TE_BADPARAM parameter is NULL
|
|
||||||
* TE_TOOMANYTS too many trees allocated already
|
|
||||||
* TE_NOROOM no memory to allocate new trees
|
|
||||||
* (te_errbuf has descriptive string)
|
|
||||||
* Exceptions: none
|
|
||||||
*/
|
|
||||||
TERNARY
|
|
||||||
ternary_new(void)
|
|
||||||
{
|
|
||||||
int cur; /* index of current tree */
|
|
||||||
TERNARY token; /* new token for current tree */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check for array full
|
|
||||||
*/
|
|
||||||
for (cur = 0; cur < MAXTREES; cur++)
|
|
||||||
if (trees[cur] == NULL)
|
|
||||||
break;
|
|
||||||
|
|
||||||
if (cur == MAXTREES) {
|
|
||||||
ERRBUF2("ternary_new: too many trees (max %d)", MAXTREES);
|
|
||||||
return TE_TOOMANYTS;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Allocate a new tree
|
|
||||||
*/
|
|
||||||
if ((trees[cur] = safemalloc(sizeof(Ttree))) == NULL) {
|
|
||||||
ERRBUF("ternary_new: malloc: no more memory");
|
|
||||||
return TE_NOROOM;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Generate token
|
|
||||||
*/
|
|
||||||
if (TE_ISERROR(token = create_token_ref(cur))) {
|
|
||||||
/* error in token generation -- clean up and return */
|
|
||||||
safefree(trees[cur]);
|
|
||||||
trees[cur] = NULL;
|
|
||||||
return token;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Now initialize tree entry
|
|
||||||
*/
|
|
||||||
trees[cur]->token = token;
|
|
||||||
trees[cur]->tree_root = trees[cur]->buf = NULL;
|
|
||||||
trees[cur]->bufn = trees[cur]->freen = 0;
|
|
||||||
|
|
||||||
return token;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Delete an exisiting tree
|
|
||||||
*
|
|
||||||
* Parameters: TERNARY tno token for the tree to be deleted
|
|
||||||
* Returned: uint16_t error code
|
|
||||||
* Errors: TE_BADPARAM parameter refers to deleted, unallocated,
|
|
||||||
* or invalid tree (from read_token_ref()).
|
|
||||||
* TE_INTINCON tree is internally inconsistent (from
|
|
||||||
* read_token_ref()).
|
|
||||||
* Exceptions: none
|
|
||||||
*/
|
|
||||||
int
|
|
||||||
ternary_destroy(TERNARY tno, void (*freeptr) (void *))
|
|
||||||
{
|
|
||||||
int cur; /* index of current tree */
|
|
||||||
unsigned int i, j;
|
|
||||||
Tnode *ptr;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check that tno refers to an existing tree;
|
|
||||||
* read_token_ref sets error code
|
|
||||||
*/
|
|
||||||
if (TE_ISERROR(cur = read_token_ref(tno)))
|
|
||||||
return cur;
|
|
||||||
|
|
||||||
for (i = 0; i < trees[cur]->freen; i++) {
|
|
||||||
for (j = 0; j < BUFSIZE; j++) {
|
|
||||||
DEBUG2("first: j = %d, i = %d", j, i);
|
|
||||||
|
|
||||||
ptr = (trees[cur]->freearr[i] + j);
|
|
||||||
if (ptr->splitchar == 0)
|
|
||||||
if (freeptr)
|
|
||||||
(*freeptr) (ptr->eqkid);
|
|
||||||
}
|
|
||||||
safefree(trees[cur]->freearr[i]);
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Remove the tree and NULL it's position in the array */
|
|
||||||
safefree(trees[cur]);
|
|
||||||
|
|
||||||
return TE_NONE;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Insert the key/value into an existing tree
|
|
||||||
*
|
|
||||||
* Parameters: TERNARY tno tree to insert data into
|
|
||||||
* char *s NULL terminated string (key)
|
|
||||||
* void *data data to associate with key (can be NULL)
|
|
||||||
* Returned: int error code
|
|
||||||
* Errors: TE_BADPARAM parameter refers to deleted, unallocated, or
|
|
||||||
* invalid tree (from read_token_ref()).
|
|
||||||
* TE_INTINCON tree is internally inconsistent (from
|
|
||||||
* read_token_ref()).
|
|
||||||
* TE_TOOFULL tree is full, so no new elements can be added.
|
|
||||||
* Exceptions: none
|
|
||||||
*/
|
|
||||||
int
|
|
||||||
ternary_insert_replace(TERNARY tno, const char *s, void *data,
|
|
||||||
short int replace)
|
|
||||||
{
|
|
||||||
int cur; /* index of current tree */
|
|
||||||
Ttree *tree; /* pointer to tree structure */
|
|
||||||
int d;
|
|
||||||
Tnode *pp, **p;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check that tno refers to an existing tree; read_token_ref sets error
|
|
||||||
* code.
|
|
||||||
*/
|
|
||||||
if (TE_ISERROR(cur = read_token_ref(tno)))
|
|
||||||
return cur;
|
|
||||||
|
|
||||||
tree = trees[cur];
|
|
||||||
p = &(tree->tree_root);
|
|
||||||
|
|
||||||
while ((pp = *p)) {
|
|
||||||
if ((d = *s - pp->splitchar) == 0) {
|
|
||||||
if (*s++ == 0) {
|
|
||||||
if (!replace)
|
|
||||||
return TE_EXISTS;
|
|
||||||
else {
|
|
||||||
free(pp->eqkid);
|
|
||||||
pp->eqkid = (Tnode *) data;
|
|
||||||
return TE_NONE;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
p = &(pp->eqkid);
|
|
||||||
} else if (d < 0)
|
|
||||||
p = &(pp->lokid);
|
|
||||||
else
|
|
||||||
p = &(pp->hikid);
|
|
||||||
}
|
|
||||||
|
|
||||||
for (;;) {
|
|
||||||
if (tree->bufn-- == 0) {
|
|
||||||
tree->buf = safecalloc(BUFSIZE, sizeof(Tnode));
|
|
||||||
if (!tree->buf) {
|
|
||||||
ERRBUF
|
|
||||||
("ternary_insert: malloc: no more memory");
|
|
||||||
return TE_NOROOM;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (tree->freen == BUFARRAY - 1) {
|
|
||||||
ERRBUF3("ternary_insert: freen %u equals %u",
|
|
||||||
tree->freen, BUFARRAY - 1);
|
|
||||||
return TE_TOOFULL;
|
|
||||||
}
|
|
||||||
|
|
||||||
tree->freearr[tree->freen++] = tree->buf;
|
|
||||||
tree->bufn = BUFSIZE - 1;
|
|
||||||
}
|
|
||||||
*p = tree->buf++;
|
|
||||||
|
|
||||||
pp = *p;
|
|
||||||
pp->splitchar = *s;
|
|
||||||
pp->lokid = pp->eqkid = pp->hikid = NULL;
|
|
||||||
if (*s++ == 0) {
|
|
||||||
pp->eqkid = (Tnode *) data;
|
|
||||||
return TE_NONE;
|
|
||||||
}
|
|
||||||
p = &(pp->eqkid);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Return the data stored with the string
|
|
||||||
*
|
|
||||||
* Parameters: TERNARY tno token for the tree involved
|
|
||||||
* char *s the name the data is stored under
|
|
||||||
* void **d the data (or NULL if you don't care about data)
|
|
||||||
* Returned: int error codes
|
|
||||||
* Errors:
|
|
||||||
* Exceptions:
|
|
||||||
*/
|
|
||||||
int
|
|
||||||
ternary_search(TERNARY tno, const char *s, void **data)
|
|
||||||
{
|
|
||||||
int cur;
|
|
||||||
Tnode *p;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Check that tno refers to an existing tree; read_token_ref sets error
|
|
||||||
* code
|
|
||||||
*/
|
|
||||||
if (TE_ISERROR(cur = read_token_ref(tno)))
|
|
||||||
return cur;
|
|
||||||
|
|
||||||
p = trees[cur]->tree_root;
|
|
||||||
|
|
||||||
while (p) {
|
|
||||||
if (toupper(*s) < toupper(p->splitchar))
|
|
||||||
p = p->lokid;
|
|
||||||
else if (toupper(*s) == toupper(p->splitchar)) {
|
|
||||||
if (*s++ == 0) {
|
|
||||||
if (data)
|
|
||||||
*data = (void *) p->eqkid;
|
|
||||||
return TE_NONE;
|
|
||||||
}
|
|
||||||
p = p->eqkid;
|
|
||||||
} else
|
|
||||||
p = p->hikid;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (data)
|
|
||||||
*data = (void *) NULL;
|
|
||||||
return TE_EMPTY;
|
|
||||||
}
|
|
||||||
@ -1,68 +0,0 @@
|
|||||||
/* $Id: ternary.h,v 1.4 2001-11-22 00:31:10 rjkaes Exp $
|
|
||||||
*
|
|
||||||
* See 'ternary.c' for a detailed description.
|
|
||||||
*
|
|
||||||
* Copyright (C) 2000 Robert James Kaes (rjkaes@flarenet.com)
|
|
||||||
*
|
|
||||||
* This program 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.
|
|
||||||
*
|
|
||||||
* This program 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.
|
|
||||||
*/
|
|
||||||
|
|
||||||
#ifndef _TINYPROXY_TERNARY_H_
|
|
||||||
#define _TINYPROXY_TERNARY_H_
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Holds our token for a ternary tree.
|
|
||||||
*/
|
|
||||||
typedef long int TERNARY;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Macros for testing for errors from the various functions.
|
|
||||||
*/
|
|
||||||
#define TE_ISERROR(x) ((x) < 0) /* true if x is tlib error code */
|
|
||||||
#define TE_NONE 0 /* no errors */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Contains any error messages from the functions.
|
|
||||||
*/
|
|
||||||
extern char te_errbuf[256];
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Macros to fill in te_errbuf
|
|
||||||
*/
|
|
||||||
#define ERRBUF(str) strncpy(te_errbuf, str, sizeof(te_errbuf))
|
|
||||||
#define ERRBUF2(str,n) sprintf(te_errbuf, str, n)
|
|
||||||
#define ERRBUF3(str,n,m) sprintf(te_errbuf, str, n, m)
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Error return codes
|
|
||||||
*/
|
|
||||||
#define TE_BADTOKEN -3 /* back token for the trees */
|
|
||||||
#define TE_EMPTY -4 /* there is no data found */
|
|
||||||
#define TE_TOOFULL -5 /* the buffers are filled */
|
|
||||||
#define TE_NOROOM -6 /* can't allocate space (sys err) */
|
|
||||||
#define TE_TOOMANYTS -7 /* too many trees in use */
|
|
||||||
#define TE_INTINCON -8 /* internal inconsistency */
|
|
||||||
#define TE_EXISTS -9 /* key already exists in tree */
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Library functions.
|
|
||||||
*/
|
|
||||||
extern TERNARY ternary_new(void);
|
|
||||||
extern int ternary_destroy(TERNARY tno, void (*freeptr) (void *));
|
|
||||||
|
|
||||||
#define ternary_insert(x, y, z) ternary_insert_replace(x, y, z, 0)
|
|
||||||
#define ternary_replace(x, y, z) ternary_insert_replace(x, y, z, 1)
|
|
||||||
|
|
||||||
extern int ternary_insert_replace(TERNARY tno, const char *s, void *data,
|
|
||||||
short int replace);
|
|
||||||
extern int ternary_search(TERNARY tno, const char *s, void **data);
|
|
||||||
|
|
||||||
#endif
|
|
||||||
Loading…
Reference in New Issue
Block a user