hop-2012/experiments/cmsg/direct.c

111 lines
3.0 KiB
C

/* Copyright (C) 2010, 2011 Tony Garnock-Jones. All rights reserved. */
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include <ucontext.h>
#include "cmsg_private.h"
#include "harness.h"
#include "ref.h"
#include "sexp.h"
#include "hashtable.h"
#include "node.h"
#include "messages.h"
#include "subscription.h"
#include "sexpio.h"
typedef struct direct_extension_t_ {
sexp_t *name;
hashtable_t routing_table;
hashtable_t subscriptions;
} direct_extension_t;
static sexp_t *direct_extend(node_t *n, sexp_t *args) {
if ((sexp_length(args) == 1) && sexp_stringp(sexp_head(args))) {
cmsg_bytes_t name = sexp_data(sexp_head(args));
direct_extension_t *d = calloc(1, sizeof(*d));
d->name = INCREF(sexp_head(args));
init_hashtable(&d->routing_table, 5, NULL, NULL);
init_hashtable(&d->subscriptions, 5, NULL, NULL);
n->extension = d;
return bind_node(name, n) ? NULL : sexp_cstring("bind failed");
} else {
return sexp_cstring("invalid args");
}
}
static void free_direct_chain(void *context, cmsg_bytes_t key, void *value) {
free_subscription_chain(value);
}
static void direct_destructor(node_t *n) {
direct_extension_t *d = n->extension;
if (d != NULL) { /* can be NULL if direct_extend was given invalid args */
DECREF(d->name, sexp_destructor);
hashtable_foreach(&d->routing_table, free_direct_chain, NULL);
destroy_hashtable(&d->routing_table);
destroy_hashtable(&d->subscriptions);
free(d);
}
}
static void route_message(direct_extension_t *d, sexp_t *rk, sexp_t *body) {
subscription_t *chain = NULL;
subscription_t *newchain;
hashtable_get(&d->routing_table, sexp_data(rk), (void **) &chain);
newchain = send_to_subscription_chain(d->name, &d->subscriptions, chain, body);
if (newchain != chain) {
hashtable_put(&d->routing_table, sexp_data(rk), newchain);
}
}
static void direct_handle_message(node_t *n, sexp_t *m) {
direct_extension_t *d = n->extension;
parsed_message_t p;
if (parse_post(m, &p)) {
if (sexp_stringp(p.post.name)) {
route_message(d, p.post.name, p.post.body);
} else {
warn("Non-string routing key in direct\n");
}
return;
}
if (parse_subscribe(m, &p)) {
subscription_t *sub = handle_subscribe_message(d->name, &d->subscriptions, &p);
if (sub != NULL) {
hashtable_get(&d->routing_table, sexp_data(p.subscribe.filter), (void **) &sub->link);
hashtable_put(&d->routing_table, sexp_data(p.subscribe.filter), sub);
}
return;
}
if (parse_unsubscribe(m, &p)) {
handle_unsubscribe_message(d->name, &d->subscriptions, &p);
return;
}
warn("Message not understood in direct: ");
sexp_writeln(stderr_h, m);
}
static node_class_t direct_class = {
.name = "direct",
.extend = direct_extend,
.destroy = direct_destructor,
.handle_message = direct_handle_message
};
void init_direct(void) {
register_node_class(&direct_class);
}