ossp-pkg/val/val.c
/*
** OSSP val - Value Access
** Copyright (c) 2002-2005 Ralf S. Engelschall <rse@engelschall.com>
** Copyright (c) 2002-2005 The OSSP Project <http://www.ossp.org/>
** Copyright (c) 2002-2005 Cable & Wireless <http://www.cw.com/>
**
** This file is part of OSSP val, a value access library which
** can be found at http://www.ossp.org/pkg/lib/val/.
**
** Permission to use, copy, modify, and distribute this software for
** any purpose with or without fee is hereby granted, provided that
** the above copyright notice and this permission notice appear in all
** copies.
**
** THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 AUTHORS AND COPYRIGHT HOLDERS AND THEIR
** 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.
**
** val.c: library implementation
*/
/* include optional Autoconf header */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
/* include system API headers */
#include <stdio.h> /* for "size_t" */
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
/* optional memory debugging support */
#if defined(HAVE_DMALLOC_H) && defined(WITH_DMALLOC)
#include "dmalloc.h"
#endif
/* include own API header */
#include "val.h"
/* boolean values */
#ifndef FALSE
#define FALSE (0)
#endif
#ifndef TRUE
#define TRUE (!FALSE)
#endif
/* unique library identifier */
const char val_id[] = "OSSP val";
/* support for OSSP ex based exception throwing */
#ifdef WITH_EX
#include "ex.h"
#define VAL_RC(rv) \
( (rv) != VAL_OK && (ex_catching && !ex_shielding) \
? (ex_throw(val_id, NULL, (rv)), (rv)) : (rv) )
#else
#define VAL_RC(rv) (rv)
#endif /* WITH_EX */
/*
** ____ ____
** ____ LINEAR HASHING SUB-LIBRARY ____
**
** This part implements a Dynamic Hash Table, based on WITOLD LITWIN
** and PER-AKE LARSON's ``Linear Hashing'' algorithm (1980/1988),
** implemented on top of a two-level virtual array with separate
** collision chains as the backend data structure. Some ideas were
** taken over from MIKAEL PETTERSON's Linear Hashing enhancements
** (1993). The code is derived from OSSP act. See there for details.
*/
struct lh_st;
typedef struct lh_st lh_t;
typedef int (*lh_cb_t)(void *ctx, const void *keyptr, int keylen, const void *datptr, int datlen);
/* fixed size (number of pointers) of the directory and of each segment */
#define INITDIRSIZE 256 /* can be an arbitrary value */
#define SEGMENTSIZE 512 /* has to be a power of 2 for below arithmetic */
/* the borders for the hash table load */
#define MINLOADFCTR 1 /* should be between 0 and 1 */
#define MAXLOADFCTR 2 /* should be between 2 and 4 */
/* the per-element structure (keep as small as possible!) */
typedef struct element_st element_t;
struct element_st {
element_t *e_next; /* pointer to next element in collision chain */
unsigned long e_hash; /* cached hash value of element (rehashing optimization) */
void *e_keyptr; /* pointer to key (= also pointer to key+data memory chunk) */
void *e_datptr; /* pointer to data in key+data memory chunk */
void *e_endptr; /* pointer to end of key+data memory chunk */
};
/* the hash table segments */
typedef struct segment_st segment_t;
struct segment_st {
element_t *s_element[SEGMENTSIZE]; /* array of pointers to elements */
};
/* the top-level hash table structure */
struct lh_st {
unsigned int h_p; /* pointer to start of unsplit region */
unsigned int h_pmax; /* pointer to end of unsplit region */
int h_slack; /* grow/shrink indicator */
unsigned h_dirsize; /* current size of directory */
segment_t **h_dir; /* pointer to directory */
};
/* on-the-fly calculate index into directory and segment from virtual array index */
#define DIRINDEX(addr) (int)((addr) / SEGMENTSIZE)
#define SEGINDEX(addr) (int)((addr) % SEGMENTSIZE)
/* on-the-fly calculate lengths of key and data to reduce memory in element_t */
#define el_keylen(el) ((char *)((el)->e_endptr)-(char *)((el)->e_keyptr))
#define el_datlen(el) ((char *)((el)->e_keyptr)-(char *)((el)->e_datptr))
/*
* BJDDJ Hash Function (Bob Jenkins, Dr. Dobbs Journal):
* This is a very complex but also very good hash function, as proposed
* in the March'97 issue of Dr. Dobbs Journal (DDJ) by Bob Jenkins (see
* http://burtleburtle.net/bob/hash/doobs.html for online version). He
* showed that this hash function has both very good distribution and
* performance and our own hash function comparison confirmed this. The
* only difference to the original function of B.J. here is that our
* version doesn't provide the `level' (= previous hash) argument for
* consistency reasons with the other hash functions (i.e. same function
* signature). It can be definetely recommended as a good general
* purpose hash function.
*/
static long
lh_hash(
register const unsigned char *k,
register size_t length)
{
register long a,b,c,len;
/* some abbreviations */
#define ub4 long
#define mix(a,b,c) { \
a -= b; a -= c; a ^= (c>>13); \
b -= c; b -= a; b ^= (a<< 8); \
c -= a; c -= b; c ^= (b>>13); \
a -= b; a -= c; a ^= (c>>12); \
b -= c; b -= a; b ^= (a<<16); \
c -= a; c -= b; c ^= (b>> 5); \
a -= b; a -= c; a ^= (c>> 3); \
b -= c; b -= a; b ^= (a<<10); \
c -= a; c -= b; c ^= (b>>15); \
}
/* setup the internal state */
len = length;
a = b = 0x9e3779b9; /* the golden ratio; an arbitrary value */
c = 0;
/* handle most of the key */
while (len >= 12) {
a += (k[0] +((ub4)k[1]<<8) +((ub4)k[ 2]<<16) +((ub4)k[ 3]<<24));
b += (k[4] +((ub4)k[5]<<8) +((ub4)k[ 6]<<16) +((ub4)k[ 7]<<24));
c += (k[8] +((ub4)k[9]<<8) +((ub4)k[10]<<16) +((ub4)k[11]<<24));
mix(a,b,c);
k += 12; len -= 12;
}
/* handle the last 11 bytes */
c += length;
switch(len) {
/* all the case statements fall through */
case 11: c+=((ub4)k[10]<<24);
case 10: c+=((ub4)k[ 9]<<16);
case 9 : c+=((ub4)k[ 8]<< 8);
/* the first byte of c is reserved for the length */
case 8 : b+=((ub4)k[ 7]<<24);
case 7 : b+=((ub4)k[ 6]<<16);
case 6 : b+=((ub4)k[ 5]<< 8);
case 5 : b+=k[4];
case 4 : a+=((ub4)k[ 3]<<24);
case 3 : a+=((ub4)k[ 2]<<16);
case 2 : a+=((ub4)k[ 1]<< 8);
case 1 : a+=k[0];
/* case 0: nothing left to add */
}
mix(a,b,c);
#undef ub4
#undef mix
/* report the result */
return c;
}
/* create the hash table structure */
static lh_t *lh_create(void)
{
lh_t *h;
/* allocate hash structure */
if ((h = (lh_t *)malloc(sizeof(lh_t))) == NULL)
return NULL;
/* allocate and clear hash table directory */
h->h_dirsize = INITDIRSIZE;
if ((h->h_dir = (segment_t **)malloc(h->h_dirsize * sizeof(segment_t *))) == NULL) {
free(h);
return NULL;
}
memset(h->h_dir, 0, h->h_dirsize * sizeof(segment_t *));
/* allocate and clear first segment of hash table array */
if ((h->h_dir[0] = (segment_t *)malloc(sizeof(segment_t))) == NULL) {
free(h->h_dir);
free(h);
return NULL;
}
memset(h->h_dir[0], 0, sizeof(segment_t));
/* initialize hash table control attributes */
h->h_p = 0;
h->h_pmax = SEGMENTSIZE;
h->h_slack = SEGMENTSIZE * MAXLOADFCTR;
return h;
}
/* expand the hash table */
static void lh_expand(lh_t *h)
{
unsigned int pmax0;
unsigned int newaddr;
segment_t *seg;
element_t **pelold;
element_t *el, *headofold, *headofnew, *next;
unsigned int n;
/* calculate next new address */
pmax0 = h->h_pmax;
newaddr = pmax0 + h->h_p;
/* have to enlarge directory? */
if (h->h_dirsize <= DIRINDEX(newaddr)) {
n = h->h_dirsize * sizeof(segment_t *);
h->h_dirsize *= 2;
if ((h->h_dir = (segment_t **)realloc(
h->h_dir, h->h_dirsize*sizeof(segment_t *))) == NULL)
return;
memset((char *)h->h_dir+n, 0, n);
}
/* have to create a new table segment? */
if (SEGINDEX(newaddr) == 0) {
if ((seg = (segment_t *)malloc(sizeof(segment_t))) == NULL)
return;
memset(seg, 0, sizeof(segment_t));
h->h_dir[DIRINDEX(newaddr)] = seg;
}
/* locate P-element */
pelold = &h->h_dir[DIRINDEX(h->h_p)]->s_element[SEGINDEX(h->h_p)];
/* adjust the state variables */
if (++(h->h_p) >= h->h_pmax) {
h->h_pmax = (h->h_pmax << 1); /* == h->h_pmax * 2 */
h->h_p = 0;
}
h->h_slack += MAXLOADFCTR;
/* relocate and split between P-element new element */
headofold = NULL;
headofnew = NULL;
for (el = *pelold; el != NULL; el = next) {
next = el->e_next;
if (el->e_hash & pmax0) {
el->e_next = headofnew;
headofnew = el;
} else {
el->e_next = headofold;
headofold = el;
}
}
*pelold = headofold;
h->h_dir[DIRINDEX(newaddr)]->s_element[SEGINDEX(newaddr)] = headofnew;
return;
}
/* shrink hash table */
static void lh_shrink(lh_t *h)
{
segment_t *lastseg;
element_t **pel;
unsigned int oldlast;
unsigned int dirsize;
void *dir;
/* calculate old last element */
oldlast = h->h_p + h->h_pmax - 1;
/* we cannot shrink below one segment */
if (oldlast == 0)
return;
/* adjust the state variables */
if (h->h_p == 0) {
h->h_pmax = (h->h_pmax >> 1); /* == h->h_pmax / 2 */;
h->h_p = h->h_pmax - 1;
} else
h->h_p--;
h->h_slack -= MAXLOADFCTR;
/* relocate the lost old last element to the end of the P-element */
pel = &h->h_dir[DIRINDEX(h->h_p)]->s_element[SEGINDEX(h->h_p)];
while (*pel != NULL)
pel = &((*pel)->e_next);
lastseg = h->h_dir[DIRINDEX(oldlast)];
*pel = lastseg->s_element[SEGINDEX(oldlast)];
lastseg->s_element[SEGINDEX(oldlast)] = NULL;
/* if possible, deallocate the last segment */
if (SEGINDEX(oldlast) == 0) {
h->h_dir[DIRINDEX(oldlast)] = NULL;
free(lastseg);
}
/* if possible, deallocate the end of the directory */
if (h->h_dirsize > INITDIRSIZE && DIRINDEX(oldlast) < h->h_dirsize/2) {
dirsize = (h->h_dirsize >> 1); /* == h->h_dirsize / 2 */
if ((dir = (segment_t **)realloc(
h->h_dir, dirsize*sizeof(segment_t *))) != NULL) {
h->h_dirsize = dirsize;
h->h_dir = dir;
}
}
return;
}
/* insert element into hash table */
static int lh_insert(lh_t *h, const void *keyptr, int keylen, const void *datptr, int datlen, int override)
{
unsigned int hash, addr;
element_t *el, **pel;
int bFound;
void *vp;
/* argument consistency check */
if (h == NULL || keyptr == NULL || keylen <= 0)
return FALSE;
/* calculate hash address */
hash = lh_hash(keyptr, keylen);
addr = hash % h->h_pmax; /* unsplit region */
if (addr < h->h_p)
addr = hash % (h->h_pmax << 1); /* split region */
/* locate hash element's collision list */
pel = &h->h_dir[DIRINDEX(addr)]->s_element[SEGINDEX(addr)];
/* check whether element is already in the hash table */
bFound = FALSE;
for (el = *pel; el != NULL; el = el->e_next) {
if ( el->e_hash == hash
&& el_keylen(el) == keylen
&& memcmp(el->e_keyptr, keyptr, el_keylen(el)) == 0) {
bFound = TRUE;
break;
}
}
/* only override on request */
if (bFound && !override)
return FALSE;
/* create a duplicate of key and data */
if ((vp = malloc(keylen+datlen)) == NULL)
return FALSE;
memmove(vp, datptr, datlen);
memmove(((char *)vp)+datlen, keyptr, keylen);
datptr = vp;
keyptr = ((char *)vp)+datlen;
if (bFound) {
/* reuse existing element by freeing old contents */
if (el->e_datptr != NULL)
free(el->e_datptr);
}
else {
/* allocate new element and chain into list */
if ((el = (element_t *)malloc(sizeof(element_t))) == 0) {
free(vp);
return FALSE;
}
while (*pel != NULL)
pel = &((*pel)->e_next);
el->e_next = *pel;
*pel = el;
}
/* insert contents into element structure */
el->e_keyptr = (void *)keyptr;
el->e_datptr = (void *)datptr;
el->e_endptr = (char *)keyptr+keylen;
el->e_hash = hash;
/* do we need to expand the table now? */
if (--(h->h_slack) < 0)
lh_expand(h);
return TRUE;
}
/* lookup an element in hash table */
static int lh_lookup(lh_t *h, const void *keyptr, int keylen, void **datptr, int *datlen)
{
unsigned int hash, addr;
element_t *el, **pel;
/* argument consistency check */
if (h == NULL || keyptr == NULL || keylen <= 0)
return FALSE;
/* calculate hash address */
hash = lh_hash(keyptr, keylen);
addr = hash % h->h_pmax; /* unsplit region */
if (addr < h->h_p)
addr = hash % (h->h_pmax << 1); /* split region */
/* locate hash element collision list */
pel = &h->h_dir[DIRINDEX(addr)]->s_element[SEGINDEX(addr)];
/* search for element in collision list */
for (el = *pel; el != NULL; el = el->e_next) {
if ( el->e_hash == hash
&& el_keylen(el) == keylen
&& memcmp(el->e_keyptr, keyptr, el_keylen(el)) == 0) {
/* provide results */
if (datptr != NULL)
*datptr = el->e_datptr;
if (datlen != NULL)
*datlen = el_datlen(el);
return TRUE;
}
}
return FALSE;
}
/* delete an element in hash table */
static int lh_delete(lh_t *h, const void *keyptr, int keylen)
{
unsigned int hash, addr;
element_t *el, *lel, **pel;
int rv;
/* argument consistency check */
if (h == NULL || keyptr == NULL || keylen <= 0)
return FALSE;
/* calculate hash address */
hash = lh_hash(keyptr, keylen);
addr = hash % h->h_pmax; /* unsplit region */
if (addr < h->h_p)
addr = hash % (h->h_pmax << 1); /* split region */
/* locate hash element collision chain */
pel = &h->h_dir[DIRINDEX(addr)]->s_element[SEGINDEX(addr)];
/* search for element in collision chain */
rv = FALSE;
for (lel = NULL, el = *pel; el != NULL; lel = el, el = el->e_next) {
if ( el->e_hash == hash
&& el_keylen(el) == keylen
&& memcmp(el->e_keyptr, keyptr, el_keylen(el)) == 0) {
/* free key+data memory chunk */
if (el->e_datptr != NULL)
free(el->e_datptr);
/* remove element from collision chain */
if (lel == NULL)
*pel = el->e_next;
else
lel->e_next = el->e_next;
/* deallocate element structure */
free(el);
rv = TRUE;
break;
}
}
/* do we need to shrink the table now? */
if (++(h->h_slack) > ((h->h_pmax + h->h_p) * (MAXLOADFCTR-MINLOADFCTR)))
lh_shrink(h);
return rv;
}
/* apply a callback for all elements in the hash table */
static int lh_apply(lh_t *h, lh_cb_t cb, void *ctx)
{
element_t *el;
unsigned int i, j;
/* argument consistency check */
if (h == NULL || cb == NULL)
return FALSE;
/* interate over all segment's entries */
for (i = 0; i < h->h_dirsize; i++) {
if (h->h_dir[i] == NULL)
continue;
/* interate over all collision chains */
for (j = 0; j < SEGMENTSIZE; j++) {
if (h->h_dir[i]->s_element[j] == NULL)
continue;
/* interate over all elements in collision chain */
el = h->h_dir[i]->s_element[j];
for (; el != NULL; el = el->e_next) {
if (!cb(ctx, el->e_keyptr, el_keylen(el), el->e_datptr, el_datlen(el)))
return FALSE;
}
}
}
return TRUE;
}
/* destroy the whole hash table */
static int lh_destroy(lh_t *h)
{
element_t *el, **pel, *el_next;
unsigned int i, j;
/* argument consistency check */
if (h == NULL)
return FALSE;
/* deallocate all segment's entries */
for (i = 0; i < h->h_dirsize; i++) {
if (h->h_dir[i] == NULL)
continue;
/* deallocate all collision chains */
for (j = 0; j < SEGMENTSIZE; j++) {
if (h->h_dir[i]->s_element[j] == NULL)
continue;
/* deallocate all elements in collision chain */
pel = &h->h_dir[i]->s_element[j];
for (el = *pel; el != NULL; ) {
/* deallocate key+data memory chunk */
if (el->e_datptr != NULL)
free(el->e_datptr);
el_next = el->e_next;
free(el);
el = el_next;
}
}
free(h->h_dir[i]);
}
/* deallocate hash table directory */
free(h->h_dir);
/* deallocate hash table top-level structure */
free(h);
return TRUE;
}
/*
** ____ ____
** ____ VALUE LIBRARY ____
**
** This part implements the actual Value library. Fortunately this
** is now easy because it internally is just based on the above
** full-featured linear hashing library.
*/
/*
* usually val_object_t.data is a pointer val_object_t.data.p,
* but VAL_INLINE signals val_object_t.data is actual data
* val_object_t.data.[csilfd].
*/
enum {
VAL_INLINE = 1<<31
};
/* the internal representation of a value object */
typedef struct {
int type;
union {
val_t *v;
void *p;
char c;
short s;
int i;
long l;
float f;
double d;
} data;
char *desc;
} val_object_t;
/* the val_t internally is just a hash table */
struct val_s {
lh_t *lh;
};
/* determine address of an object's storage */
static void *val_storage(val_object_t *obj)
{
void *storage;
/* argument consistency check */
if (obj == NULL)
return NULL;
/* address determination */
if (obj->type & VAL_INLINE) {
switch (obj->type & ~VAL_INLINE) {
case VAL_TYPE_VAL: storage = &obj->data.v; break;
case VAL_TYPE_PTR: storage = &obj->data.p; break;
case VAL_TYPE_CHAR: storage = &obj->data.c; break;
case VAL_TYPE_SHORT: storage = &obj->data.s; break;
case VAL_TYPE_INT: storage = &obj->data.i; break;
case VAL_TYPE_LONG: storage = &obj->data.l; break;
case VAL_TYPE_FLOAT: storage = &obj->data.f; break;
case VAL_TYPE_DOUBLE: storage = &obj->data.d; break;
default: storage = NULL; break; /* cannot happen */
}
}
else
storage = obj->data.p;
return storage;
}
/* create object */
val_rc_t val_create(val_t **pval)
{
val_t *val;
/* argument consistency check */
if (pval == NULL)
return VAL_RC(VAL_ERR_ARG);
/* create top-level structure */
if ((val = (val_t *)malloc(sizeof(val_t))) == NULL)
return VAL_RC(VAL_ERR_SYS);
/* create hash table */
if ((val->lh = lh_create()) == NULL) {
free(val);
return VAL_RC(VAL_ERR_SYS);
}
/* pass result to caller */
*pval = val;
return VAL_OK;
}
/* internal lh_apply() callback for use with val_destroy() */
static int val_destroy_cb(void *_ctx,
const void *keyptr, int keylen,
const void *datptr, int datlen)
{
val_object_t *obj;
/* free description string */
if ((obj = (val_object_t *)datptr) != NULL)
if (obj->desc != NULL)
free(obj->desc);
return TRUE;
}
/* destroy object */
val_rc_t val_destroy(val_t *val)
{
/* argument consistency check */
if (val == NULL)
return VAL_RC(VAL_ERR_ARG);
/* destroy all hash table elements */
lh_apply(val->lh, val_destroy_cb, NULL);
/* destroy hash table */
if (!lh_destroy(val->lh))
return VAL_RC(VAL_ERR_SYS);
/* destroy top-level structure */
free(val);
return VAL_OK;
}
/* register a value */
val_rc_t val_reg(val_t *val, const char *name, int type, const char *desc, void *storage)
{
val_object_t *obj;
val_object_t newobj;
const char *cp;
val_t *child;
/* argument consistency check */
if (val == NULL || name == NULL || type == 0)
return VAL_RC(VAL_ERR_ARG);
/* recursive step-down on structured name */
if ((cp = strchr(name, '.')) != NULL) {
if (!lh_lookup(val->lh, name, cp-name, (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
return val_reg(child, cp+1, type, desc, storage);
}
/* create a new value object */
if (desc != NULL)
newobj.desc = strdup(desc);
else
newobj.desc = NULL;
if (storage == NULL) {
newobj.type = (type | VAL_INLINE);
newobj.data.l = 0;
}
else {
newobj.type = (type & ~VAL_INLINE);
newobj.data.p = storage;
}
/* insert value into hash table */
if (!lh_insert(val->lh, name, strlen(name), &newobj, sizeof(newobj), 1))
return VAL_RC(VAL_ERR_HSH);
return VAL_OK;
}
val_rc_t val_unreg(val_t *val, const char *name)
{
val_object_t *obj;
const char *cp;
val_t *child;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* recursive step-down on structured name */
if ((cp = strchr(name, '.')) != NULL) {
if (!lh_lookup(val->lh, name, cp-name, (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
return val_unreg(child, cp+1);
}
/* try to lookup object in hash table */
if (!lh_lookup(val->lh, name, strlen(name), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
/* destroy value object */
if (obj->desc != NULL)
free(obj->desc);
/* delete value from hash table */
if (!lh_delete(val->lh, name, strlen(name)))
return VAL_RC(VAL_ERR_HSH);
return VAL_OK;
}
/* query information about a value */
val_rc_t val_query(val_t *val, const char *name,
int *ptype, char **pdesc, void **pstorage)
{
char *cp;
val_object_t *obj;
val_t *child;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* recursive step-down on structured name */
if ((cp = strchr(name, '.')) != NULL) {
if (!lh_lookup(val->lh, name, cp-name, (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
return val_query(child, cp+1, ptype, pdesc, pstorage);
}
/* try to lookup object in hash table */
if (!lh_lookup(val->lh, name, strlen(name), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
/* pass queried information to caller */
if (ptype != NULL)
*ptype = (obj->type & ~VAL_INLINE);
if (pdesc != NULL)
*pdesc = obj->desc;
if (pstorage != NULL)
*pstorage = val_storage(obj);
return VAL_OK;
}
/* set a value (va_list variant) */
val_rc_t val_vset(val_t *val, const char *name, va_list ap)
{
val_object_t *obj;
void *storage;
const char *cp;
val_t *child;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* recursive step-down on structured name */
if ((cp = strchr(name, '.')) != NULL) {
if (!lh_lookup(val->lh, name, cp-name, (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
return val_vset(child, cp+1, ap);
}
/* try to lookup object in hash table */
if (!lh_lookup(val->lh, name, strlen(name), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
/* determine value storage */
if ((storage = val_storage(obj)) == NULL)
return VAL_RC(VAL_ERR_INT);
/* copy value from variable argument into storage location */
switch (obj->type & ~VAL_INLINE) {
case VAL_TYPE_VAL: *(val_t **)storage = (val_t *)va_arg(ap, void *); break;
case VAL_TYPE_PTR: *(char **)storage = (char *)va_arg(ap, void *); break;
case VAL_TYPE_CHAR: *(char *)storage = (char )va_arg(ap, int ); break;
case VAL_TYPE_SHORT: *(short *)storage = (short )va_arg(ap, int ); break;
case VAL_TYPE_INT: *(int *)storage = (int )va_arg(ap, int ); break;
case VAL_TYPE_LONG: *(long *)storage = (long )va_arg(ap, long ); break;
case VAL_TYPE_FLOAT: *(float *)storage = (float )va_arg(ap, double); break;
case VAL_TYPE_DOUBLE: *(double *)storage = (double )va_arg(ap, double); break;
default: break; /* cannot happen */
}
return VAL_OK;
}
/* set a value */
val_rc_t val_set(val_t *val, const char *name, ...)
{
val_rc_t rc;
va_list ap;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* just pass-through to va_list variant */
va_start(ap, name);
rc = val_vset(val, name, ap);
va_end(ap);
return VAL_RC(rc);
}
/* get a value (va_list variant) */
val_rc_t val_vget(val_t *val, const char *name, va_list ap)
{
val_object_t *obj;
void *storage;
const char *cp;
val_t *child;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* recursive step-down on structured name */
if ((cp = strchr(name, '.')) != NULL) {
if (!lh_lookup(val->lh, name, cp-name, (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
return val_vget(child, cp+1, ap);
}
/* try to lookup object in hash table */
if (!lh_lookup(val->lh, name, strlen(name), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
/* determine value storage */
if ((storage = val_storage(obj)) == NULL)
return VAL_RC(VAL_ERR_INT);
/* copy value from storage location into variable argument pointer location */
switch (obj->type & ~VAL_INLINE) {
case VAL_TYPE_VAL: *((val_t **)va_arg(ap, void *)) = *(val_t **)storage; break;
case VAL_TYPE_PTR: *((char **)va_arg(ap, void *)) = *(char **)storage; break;
case VAL_TYPE_CHAR: *((char *)va_arg(ap, int *)) = *(char *)storage; break;
case VAL_TYPE_SHORT: *((short *)va_arg(ap, int *)) = *(short *)storage; break;
case VAL_TYPE_INT: *((int *)va_arg(ap, int *)) = *(int *)storage; break;
case VAL_TYPE_LONG: *((long *)va_arg(ap, long *)) = *(long *)storage; break;
case VAL_TYPE_FLOAT: *((float *)va_arg(ap, double *)) = *(float *)storage; break;
case VAL_TYPE_DOUBLE: *((double *)va_arg(ap, double *)) = *(double *)storage; break;
default: break; /* cannot happen */
}
return VAL_OK;
}
/* get a value */
val_rc_t val_get(val_t *val, const char *name, ...)
{
val_rc_t rc;
va_list ap;
/* argument consistency check */
if (val == NULL || name == NULL)
return VAL_RC(VAL_ERR_ARG);
/* just pass-through to va_list variant */
va_start(ap, name);
rc = val_vget(val, name, ap);
va_end(ap);
return VAL_RC(rc);
}
/* internal lh_apply() recursion callback context structure */
typedef struct {
val_t *val;
char *name;
int prefixlen;
int depth;
val_cb_t cb;
void *ctx;
val_rc_t rc;
} val_apply_ctx_t;
/* forward declaration */
static val_rc_t val_apply_internal(val_t *, const char *, int, int, val_cb_t, void *);
/* internal lh_apply() recursion callback for use with val_apply() */
static int (val_apply_cb)(void *_ctx, const void *keyptr, int keylen, const void *datptr, int datlen)
{
val_apply_ctx_t *ctx = (val_apply_ctx_t *)_ctx;
char name[VAL_MAXNAME+1];
int prefixlen;
/* on-the-fly create NUL-terminated concatenated name string */
if ((strlen(ctx->name) + 1 + keylen) > VAL_MAXNAME) {
ctx->rc = VAL_ERR_MEM;
return FALSE;
}
if (strlen(ctx->name) > 0) {
strcpy(name, ctx->name);
strcat(name, ".");
prefixlen = ctx->prefixlen + 1;
}
else {
*name = '\0';
prefixlen = ctx->prefixlen;
}
strncat(name, (char *)keyptr, keylen);
/* recursive step-down */
if ((ctx->rc = val_apply_internal(ctx->val, name, prefixlen,
ctx->depth, ctx->cb, ctx->ctx)) != VAL_OK)
return FALSE;
return TRUE;
}
/* internal API-increased variant of val_apply() */
static val_rc_t val_apply_internal(val_t *val, const char *name, int prefixlen,
int depth, val_cb_t cb, void *ctx)
{
val_object_t *obj;
val_t *child;
char *cp;
val_rc_t rc;
val_apply_ctx_t val_ctx;
if (name[prefixlen] == '\0') {
/* CASE 1: apply to all elements
prefix="foo.bar.", remainder="" */
val_ctx.val = val;
val_ctx.name = (char *)name;
val_ctx.prefixlen = prefixlen;
val_ctx.depth = depth;
val_ctx.cb = cb;
val_ctx.ctx = ctx;
val_ctx.rc = VAL_OK;
if (!lh_apply(val->lh, val_apply_cb, &val_ctx))
return VAL_RC(VAL_ERR_SYS);
}
else if ((cp = strchr(name+prefixlen, '.')) != NULL) {
/* CASE 2: still stepping-down for structured name
prefix="foo.bar.", remainder="quux.baz" */
if (!lh_lookup(val->lh, name+prefixlen, cp-(name+prefixlen), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if (!(obj->type & VAL_TYPE_VAL))
return VAL_RC(VAL_ERR_USE);
child = *(val_t **)(val_storage(obj));
if (depth == 0)
return VAL_OK;
return val_apply_internal(child, name, cp-name+1, depth-1, cb, ctx);
} else {
/* CASE 3: reached last component of structured name
prefix="foo.bar.quux.", remainder="baz" */
if (!lh_lookup(val->lh, name+prefixlen, strlen(name+prefixlen), (void **)(void *)&obj, NULL))
return VAL_RC(VAL_ERR_ARG);
if ((rc = cb(ctx, name, (obj->type & ~VAL_INLINE),
obj->desc, val_storage(obj))) != VAL_OK)
return VAL_RC(rc);
if (obj->type & VAL_TYPE_VAL) {
if (depth == 0)
return VAL_OK;
child = *(val_t **)(val_storage(obj));
return val_apply_internal(child, name, strlen(name), depth-1, cb, ctx);
}
}
return VAL_OK;
}
/* apply a callback to each value */
val_rc_t val_apply(val_t *val, const char *name, int depth, val_cb_t cb, void *ctx)
{
/* argument consistency check */
if (val == NULL || name == NULL || depth < 0 || cb == NULL)
return VAL_RC(VAL_ERR_ARG);
/* just pass-through to internal API-extended variant */
return val_apply_internal(val, name, 0, depth, cb, ctx);
}
