handler_virt_tender.c

   1 #include "handler_virt.h"
   2 #include "handler_clusterstats.h"
   3 #include "handler_virt_tender.h"
   4 #include <cherokee/cherokee.h>
   5 #include <float.h>
   6
   7 #include <avahi-client/client.h>
   8 #include <avahi-client/publish.h>
   9 #include <avahi-client/lookup.h>
  10
  11 #include <avahi-common/alternative.h>
  12 #include <avahi-common/simple-watch.h>
  13 #include <avahi-common/malloc.h>
  14 #include <avahi-common/error.h>
  15 #include <avahi-common/timeval.h>
  16
  17 static void entry_group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
  18     switch (state) {
  19         case AVAHI_ENTRY_GROUP_ESTABLISHED :
  20             /* The entry group has been established successfully */
  21             break;
  22
  23         case AVAHI_ENTRY_GROUP_COLLISION : {
  24             /* A service name collision with a remote service
  25              * happened. */
  26             break;
  27         }
  28
  29         case AVAHI_ENTRY_GROUP_FAILURE :
  30             /* Some kind of failure happened while we were registering our services */
  31             break;
  32
  33         case AVAHI_ENTRY_GROUP_UNCOMMITED:
  34         case AVAHI_ENTRY_GROUP_REGISTERING:
  35             ;
  36     }
  37 }
  38
  39 static void tender_resolve_callback(
  40     AvahiServiceResolver *r,
  41     AVAHI_GCC_UNUSED AvahiIfIndex interface,
  42     AVAHI_GCC_UNUSED AvahiProtocol protocol,
  43     AvahiResolverEvent event,
  44     const char *name,
  45     const char *type,
  46     const char *domain,
  47     const char *host_name,
  48     const AvahiAddress *address,
  49     uint16_t port,
  50     AvahiStringList *txt,
  51     AvahiLookupResultFlags flags,
  52     void* userdata) {
  53
  54     tender_t *tender = userdata;
  55
  56     assert(r);
  57
  58     /* Called whenever a service has been resolved successfully or timed out */
  59
  60     switch (event) {
  61         case AVAHI_RESOLVER_FAILURE:
  62             // fprintf(stderr, "(Resolver) FAILURE!\n");
  63             avahi_service_resolver_free(r);
  64             break;
  65
  66         case AVAHI_RESOLVER_FOUND: {
  67             char a[AVAHI_ADDRESS_STR_MAX], *t;
  68             AvahiStringList *needle;
  69
  70 //            fprintf(stderr, "(Resolver) Service '%s' of type '%s' in domain '%s':\n", name, type, domain);
  71
  72             avahi_address_snprint(a, sizeof(a), address);
  73             t = avahi_string_list_to_string(txt);
  74 /*            fprintf(stderr,
  75                     "\t%s:%u (%s)\n"
  76                     "\tTXT=%s\n"
  77                     "\tcookie is %u\n"
  78                     "\tis_local: %i\n"
  79                     "\tour_own: %i\n"
  80                     "\twide_area: %i\n"
  81                     "\tmulticast: %i\n"
  82                     "\tcached: %i\n",
  83                     host_name, port, a,
  84                     t,
  85                     avahi_string_list_get_service_cookie(txt),
  86                     !!(flags & AVAHI_LOOKUP_RESULT_LOCAL),
  87                     !!(flags & AVAHI_LOOKUP_RESULT_OUR_OWN),
  88                     !!(flags & AVAHI_LOOKUP_RESULT_WIDE_AREA),
  89                     !!(flags & AVAHI_LOOKUP_RESULT_MULTICAST),
  90                     !!(flags & AVAHI_LOOKUP_RESULT_CACHED));*/
  91
  92
  93             avahi_free(t);
  94
  95             if (tender->name) {
  96                 unsigned int len = strlen(tender->name);
  97                 if (strlen(name) > len && name[len] == '.' && strncmp(tender->name, name, len) == 0) {
  98                     if ((needle = avahi_string_list_find (txt, "cost")) != NULL) {
  99
 100                         float amount;
 101                         char *cost;
 102                         avahi_string_list_get_pair (needle, NULL, &cost, NULL);
 103                         amount = atof(cost);
 104
 105                         TRACE("tender", "%s will run %s for the cost of L$W %f\n", host_name, tender->name, amount);
 106                         if (amount < tender->cost) {
 107                             /* TODO: LOCK */
 108                             tender->cost = amount;
 109                             tender->dom = strdup(host_name);
 110                             TRACE("tender", "We will consider his offer!");
 111                         }
 112
 113                         avahi_free(cost);
 114                     }
 115                 }
 116             }
 117             break;
 118         }
 119     }
 120 }
 121
 122 static void tender_browse_callback(
 123     AvahiServiceBrowser *b,
 124     AvahiIfIndex interface,
 125     AvahiProtocol protocol,
 126     AvahiBrowserEvent event,
 127     const char *name,
 128     const char *type,
 129     const char *domain,
 130     AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
 131     void* userdata) {
 132         AvahiClient *c;
 133         assert(b);
 134
 135         c = avahi_service_browser_get_client(b);
 136
 137     /* Called whenever a new services becomes available on the LAN or is removed from the LAN */
 138
 139     switch (event) {
 140         case AVAHI_BROWSER_FAILURE:
 141             fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_client_errno(c)));
 142             return;
 143
 144         case AVAHI_BROWSER_NEW:
 145             fprintf(stderr, "(Browser) NEW: service '%s' of type '%s' in domain '%s'\n", name, type, domain);
 146
 147             /* We ignore the returned resolver object. In the callback
 148                function we free it. If the server is terminated before
 149                the callback function is called the server will free
 150                the resolver for us. */
 151
 152             if (!(avahi_service_resolver_new(c, interface, protocol, name, type, domain, AVAHI_PROTO_UNSPEC, 0, tender_resolve_callback, userdata)))
 153                 fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_client_errno(c)));
 154
 155             break;
 156
 157         case AVAHI_BROWSER_REMOVE:
 158             fprintf(stderr, "%s, (Browser) REMOVE: service '%s' of type '%s' in domain '%s'\n", __func__, name, type, domain);
 159             break;
 160
 161         case AVAHI_BROWSER_ALL_FOR_NOW:
 162         case AVAHI_BROWSER_CACHE_EXHAUSTED:
 163             fprintf(stderr, "(Browser) %s\n", event == AVAHI_BROWSER_CACHE_EXHAUSTED ? "CACHE_EXHAUSTED" : "ALL_FOR_NOW");
 164             break;
 165     }
 166 }
 167
 168 char * create_tender(cherokee_handler_virt_t *hdl, const char *name, unsigned long memory) {
 169     char txt[255];
 170     tender_t best_tender;
 171
 172     snprintf(txt, 253, "memory=%lu", memory);
 173     txt[254] = '\0';
 174
 175     best_tender.name = name;
 176     best_tender.cost = FLT_MAX;
 177     best_tender.dom  = NULL;
 178
 179     avahi_threaded_poll_lock(HDL_CLUSTERSTATS_PROPS(hdl)->threaded_poll);
 180     AvahiServiceBrowser *sb = avahi_service_browser_new(HDL_CLUSTERSTATS_PROPS(hdl)->client, AVAHI_IF_UNSPEC,
 181                                                         AVAHI_PROTO_UNSPEC, "_tender._tcp",
 182                                                         NULL, 0, tender_browse_callback, &best_tender);
 183
 184     if (sb == NULL) {
 185         TRACE("avahi", "For whatever reason the sb is NULL\n");
 186     } else {
 187         AvahiEntryGroup *group = avahi_entry_group_new(HDL_CLUSTERSTATS_PROPS(hdl)->client, entry_group_callback, NULL);
 188
 189         if (group == NULL) {
 190             TRACE("avahi", "For whatever reason the group is NULL\n");
 191         } else {
 192             avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0,
 193                                           best_tender.name, "_offer._tcp", NULL, NULL, 651, txt, NULL, NULL);
 194             avahi_entry_group_commit(group);
 195             avahi_threaded_poll_unlock(HDL_CLUSTERSTATS_PROPS(hdl)->threaded_poll);
 196
 197             sleep(3); /* we are for quick bidding ;) */
 198
 199             avahi_threaded_poll_lock(HDL_CLUSTERSTATS_PROPS(hdl)->threaded_poll);
 200             avahi_entry_group_free(group);
 201         }
 202
 203         avahi_service_browser_free(sb);
 204     }
 205     avahi_threaded_poll_unlock(HDL_CLUSTERSTATS_PROPS(hdl)->threaded_poll);
 206
 207     return best_tender.dom;
 208 }