#include "std.h"
#include "otable.h"
#include "comm.h"
#include "hash.h"
#include "simul_efun.h"
#include "master.h"
#include "object.h"
/*
* Object name hash table. Object names are unique, so no special
* problems - like stralloc.c. For non-unique hashed names, we need
* a better package (if we want to be able to get at them all) - we
* cant move them to the head of the hash chain, for example.
*
* Note: if you change an object name, you must remove it and reenter it.
*/
static int otable_size;
static int otable_size_minus_one;
static object_t *find_obj_n(const char *);
/*
* Object hash function, ripped off from stralloc.c.
*/
#define ObjHash(s) whashstr(s) & otable_size_minus_one
/*
* hash table - list of pointers to heads of object chains.
* Each object in chain has a pointer, next_hash, to the next object.
*/
static object_t **obj_table = 0;
static object_t **ch_table = 0;
static char *basename(const char *full, int *size) {
char *name= new_string(*size = strlen(full), "base_name: name");
while (*full == '/') {
full++;
(*size)--;
}
strcpy(name, full);
char *tmp = strchr(name, '#');
if (tmp) {
*size = tmp-name;
}
while (*size > 2&& name[*size-1] == 'c'&& name[*size-2] == '.')
*size -= 2;
name[*size] = 0;
name = extend_string(name, *size);
return name;
}
void init_otable() {
int x, y;
/* ensure that otable_size is a power of 2 */
y = OTABLE_SIZE;
for (otable_size = 1; otable_size < y; otable_size *= 2)
;
otable_size_minus_one = otable_size - 1;
obj_table = CALLOCATE(otable_size, object_t *,
TAG_OBJ_TBL, "init_otable");
ch_table = CALLOCATE(otable_size, object_t *,
TAG_OBJ_TBL, "init_ch_otable");
for (x = 0; x < otable_size; x++) {
obj_table[x] = 0;
ch_table[x] = 0;
}
}
/*
* Looks for obj in table, moves it to head.
*/
static long obj_searches = 0, obj_probes = 0, objs_found = 0;
/* A global. *shhhh* don't tell. */
static int h;
static int ch;
static object_t *find_obj_n(const char * s) {
object_t *curr, *prev;
h = ObjHash(s);
curr = obj_table[h];
prev = 0;
obj_searches++;
while (curr) {
obj_probes++;
if (!strcmp(curr->obname, s)) { /* found it */
if (prev) { /* not at head of list */
prev->next_hash = curr->next_hash;
curr->next_hash = obj_table[h];
obj_table[h] = curr;
}
objs_found++;
return (curr); /* pointer to object */
}
prev = curr;
curr = curr->next_hash;
}
return (0); /* not found */
}
array_t *children(const char * s) {
object_t *curr;
int size;
s = basename(s, &size);
ch = ObjHash(s);
curr = ch_table[ch];
int count = 0;
array_t *vec = allocate_empty_array(max_array_size);
while (curr && count < max_array_size) {
if (!strncmp(curr->obname, s, size)) { /* found one */
vec->item[count].u.ob = curr;
add_ref(curr, "children");
vec->item[count].type = T_OBJECT;
count++;
}
curr = curr->next_ch_hash;
}
FREE_MSTR(s);
vec = resize_array(vec, count);
return (vec);
}
/*
* Add an object to the table - can't have duplicate names.
*
* Exception: Precompiled objects have a dummy entry here, but it is
* guaranteed to be behind the real entry if a real entry exists.
*/
static int objs_in_table = 0;
void enter_object_hash(object_t * ob) {
object_t *s;
#ifndef DEBUG
h = ObjHash(ob->obname);
#else
s = find_obj_n(ob->obname); /* This sets h */
/* when these reload, the new copy comes in before the old goes out */
if (s != master_ob && s != simul_efun_ob) {
DEBUG_CHECK1(s && s != ob,
"Duplicate object \"/%s\" in object hash table",
ob->obname);
}
#endif
ob->next_hash = obj_table[h];
obj_table[h] = ob;
objs_in_table++;
//for children()
int dummy;
char *base = basename(ob->obname, &dummy);
ch = ObjHash(base);
ob->next_ch_hash = ch_table[ch];
ch_table[ch] = ob;
FREE_MSTR(base);
return;
}
/*
* Remove an object from the table - generally called when it
* is removed from the next_all list - i.e. in destruct.
*/
void remove_object_hash(object_t * ob) {
object_t *s;
s = find_obj_n(ob->obname); /* this sets h, and cycles the ob to the front */
if (!s)
fatal("couldn't find object %s in obj_table", ob->obname);
DEBUG_CHECK1(s != ob, "Remove object \"/%s\": found a different object!",
ob->obname);
obj_table[h] = ob->next_hash;
ob->next_hash = 0;
objs_in_table--;
int dummy;
char *base = basename(ob->obname, &dummy);
ch = ObjHash(base);
FREE_MSTR(base);
object_t *t = 0;
s = ch_table[ch];
while (s && s!=ob) {
t = s;
s = s->next_ch_hash;
}
if (!s)
fatal("object not found in children list");
if (!t)
ch_table[ch] = s->next_ch_hash;
else
t->next_ch_hash = s->next_ch_hash;
ob->next_ch_hash = 0;
return;
}
/*
* Lookup an object in the hash table; if it isn't there, return null.
* This is only different to find_object_n in that it collects different
* stats; more finds are actually done than the user ever asks for.
*/
static long user_obj_lookups = 0, user_obj_found = 0;
object_t *lookup_object_hash(const char * s) {
object_t *ob = find_obj_n(s);
user_obj_lookups++;
if (ob)
user_obj_found++;
return (ob);
}
/*
* Print stats, returns the total size of the object table. All objects
* are in table, so their size is included as well.
*/
static char sbuf[100];
int show_otable_status(outbuffer_t * out, int verbose) {
int starts;
if (verbose == 1) {
outbuf_add(out, "Object name hash table status:\n");
outbuf_add(out, "------------------------------\n");
sprintf(sbuf, "%10.2f", objs_in_table / (float) OTABLE_SIZE);
outbuf_addv(out, "Average hash chain length: %s\n", sbuf);
sprintf(sbuf, "%10.2f", (float) obj_probes / obj_searches);
outbuf_addv(out, "Average search length: %s\n", sbuf);
outbuf_addv(out, "Internal lookups (succeeded): %lu (%lu)\n",
obj_searches - user_obj_lookups, objs_found - user_obj_found);
outbuf_addv(out, "External lookups (succeeded): %lu (%lu)\n",
user_obj_lookups, user_obj_found);
}
starts = (long) OTABLE_SIZE *sizeof(object_t *)+objs_in_table
* sizeof(object_t);
if (!verbose) {
outbuf_addv(out, "Obj table overhead:\t\t%8d %8d\n",
OTABLE_SIZE * sizeof(object_t *), starts);
}
return starts;
}
