haproxy/src/dict.c
Thayne McCombs 92149f9a82 MEDIUM: stick-tables: Add srvkey option to stick-table
This allows using the address of the server rather than the name of the
server for keeping track of servers in a backend for stickiness.

The peers code was also extended to support feeding the dictionary using
this key instead of the name.

Fixes #814
2020-12-31 10:04:54 +01:00

130 lines
2.4 KiB
C

#include <string.h>
#include <import/eb32tree.h>
#include <import/ebistree.h>
#include <haproxy/dict.h>
#include <haproxy/thread.h>
struct dict *new_dict(const char *name)
{
struct dict *dict;
dict = malloc(sizeof *dict);
if (!dict)
return NULL;
dict->name = name;
dict->values = EB_ROOT_UNIQUE;
HA_RWLOCK_INIT(&dict->rwlock);
return dict;
}
/*
* Allocate a new dictionary entry with <s> as string value which is strdup()'ed.
* Returns the new allocated entry if succeeded, NULL if not.
*/
static struct dict_entry *new_dict_entry(char *s)
{
struct dict_entry *de;
de = calloc(1, sizeof *de);
if (!de)
return NULL;
de->value.key = strdup(s);
if (!de->value.key)
goto err;
de->len = strlen(s);
de->refcount = 1;
return de;
err:
free(de->value.key);
de->value.key = NULL;
de->len = 0;
free(de);
return NULL;
}
/*
* Release the memory allocated for <de> dictionary entry.
*/
static void free_dict_entry(struct dict_entry *de)
{
de->refcount = 0;
free(de->value.key);
de->value.key = NULL;
free(de);
}
/*
* Simple function to lookup dictionary entries with <s> as value.
*/
static struct dict_entry *__dict_lookup(struct dict *d, const char *s)
{
struct dict_entry *de;
struct ebpt_node *node;
de = NULL;
node = ebis_lookup(&d->values, s);
if (node)
de = container_of(node, struct dict_entry, value);
return de;
}
/*
* Insert an entry in <d> dictionary with <s> as value. *
*/
struct dict_entry *dict_insert(struct dict *d, char *s)
{
struct dict_entry *de;
struct ebpt_node *n;
HA_RWLOCK_RDLOCK(DICT_LOCK, &d->rwlock);
de = __dict_lookup(d, s);
HA_RWLOCK_RDUNLOCK(DICT_LOCK, &d->rwlock);
if (de) {
HA_ATOMIC_ADD(&de->refcount, 1);
return de;
}
de = new_dict_entry(s);
if (!de)
return NULL;
HA_RWLOCK_WRLOCK(DICT_LOCK, &d->rwlock);
n = ebis_insert(&d->values, &de->value);
HA_RWLOCK_WRUNLOCK(DICT_LOCK, &d->rwlock);
if (n != &de->value) {
free_dict_entry(de);
de = container_of(n, struct dict_entry, value);
}
return de;
}
/*
* Unreference a dict entry previously acquired with <dict_insert>.
* If this is the last live reference to the entry, it is
* removed from the dictionary.
*/
void dict_entry_unref(struct dict *d, struct dict_entry *de)
{
if (!de)
return;
if (HA_ATOMIC_SUB(&de->refcount, 1) != 0)
return;
HA_RWLOCK_WRLOCK(DICT_LOCK, &d->rwlock);
ebpt_delete(&de->value);
HA_RWLOCK_WRUNLOCK(DICT_LOCK, &d->rwlock);
free_dict_entry(de);
}