* split off lookup.h and publish.h from core.h

* implement wide-area DNS-SD
* if multiple clients query the same records, only start the query packet sequence once
* implement recursive CNAME queries
* add support for resolving services without TXT or A/AAAA records
* enlarge resolving timeouts to 5s
* implement new browse/resolving events CACHE_EXHAUSTED/ALL_FOR_NOW 
* add support for resolving services without name. (i.e. for normal SRV records)


git-svn-id: file:///home/lennart/svn/public/avahi/trunk@608 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe

1 files changed, 302 insertions, 161 deletions

diff --git a/avahi-core/resolve-service.c b/avahi-core/resolve-service.c
index 0ecd388..31b0081 100644
--- a/avahi-core/resolve-service.c
+++ b/avahi-core/resolve-service.c
@@ -33,8 +33,9 @@
 #include <avahi-common/error.h>
 
 #include "browse.h"
+#include "log.h"
 
-#define TIMEOUT_MSEC 1000
+#define TIMEOUT_MSEC 5000
 
 struct AvahiSServiceResolver {
     AvahiServer *server;
@@ -52,9 +53,11 @@ struct AvahiSServiceResolver {
     AvahiSRecordBrowser *record_browser_aaaa;
 
     AvahiRecord *srv_record, *txt_record, *address_record;
+    AvahiLookupResultFlags srv_flags, txt_flags, address_flags;
     
     AvahiSServiceResolverCallback callback;
     void* userdata;
+    AvahiLookupFlags user_flags;
 
     AvahiTimeEvent *time_event;
 
@@ -62,6 +65,8 @@ struct AvahiSServiceResolver {
 };
 
 static void finish(AvahiSServiceResolver *r, AvahiResolverEvent event) {
+    AvahiLookupResultFlags flags;
+    
     assert(r);
 
     if (r->time_event) {
@@ -69,44 +74,74 @@ static void finish(AvahiSServiceResolver *r, AvahiResolverEvent event) {
         r->time_event = NULL;
     }
 
-    if (event == AVAHI_RESOLVER_TIMEOUT)
-        r->callback(r, r->interface, r->protocol, event, r->service_name, r->service_type, r->domain_name, NULL, NULL, 0, NULL, r->userdata);
-    else {
-        AvahiAddress a;
-        char sn[256], st[256];
-        size_t i;
-
-        assert(event == AVAHI_RESOLVER_FOUND);
-        
-        assert(r->srv_record);
-        assert(r->txt_record);
-        assert(r->address_record);
-        
-        switch (r->address_record->key->type) {
-            case AVAHI_DNS_TYPE_A:
-                a.proto = AVAHI_PROTO_INET;
-                a.data.ipv4 = r->address_record->data.a.address;
-                break;
-                
-            case AVAHI_DNS_TYPE_AAAA:
-                a.proto = AVAHI_PROTO_INET6;
-                a.data.ipv6 = r->address_record->data.aaaa.address;
-                break;
-                
-            default:
-                assert(0);
+    flags =
+        r->txt_flags |
+        r->srv_flags |
+        r->address_flags;
+    
+    switch (event) {
+        case AVAHI_RESOLVER_FAILURE:
+        case AVAHI_RESOLVER_NOT_FOUND:
+        case AVAHI_RESOLVER_TIMEOUT:
+            
+            r->callback(
+                r,
+                r->interface,
+                r->protocol,
+                event,
+                r->service_name,
+                r->service_type,
+                r->domain_name,
+                NULL,
+                NULL,
+                0,
+                NULL,
+                flags,
+                r->userdata);
+
+            break;
+
+        case AVAHI_RESOLVER_FOUND: {
+            AvahiAddress a;
+            
+            assert(event == AVAHI_RESOLVER_FOUND);
+            
+            assert(r->srv_record);
+
+            if (r->address_record) {
+                switch (r->address_record->key->type) {
+                    case AVAHI_DNS_TYPE_A:
+                        a.proto = AVAHI_PROTO_INET;
+                        a.data.ipv4 = r->address_record->data.a.address;
+                        break;
+                        
+                    case AVAHI_DNS_TYPE_AAAA:
+                        a.proto = AVAHI_PROTO_INET6;
+                        a.data.ipv6 = r->address_record->data.aaaa.address;
+                        break;
+                        
+                    default:
+                        assert(0);
+                }
+            }
+            
+            r->callback(
+                r,
+                r->interface,
+                r->protocol,
+                event,
+                r->service_name,
+                r->service_type,
+                r->domain_name,
+                r->address_record ? r->address_record->key->name : r->srv_record->data.srv.name,
+                r->address_record ? &a : NULL,
+                r->srv_record->data.srv.port,
+                r->txt_record ? r->txt_record->data.txt.string_list : NULL,
+                flags,
+                r->userdata);
+
+            break;
         }
-
-        snprintf(sn, sizeof(sn), r->service_name);
-        snprintf(st, sizeof(st), r->service_type);
-
-        if ((i = strlen(sn)) > 0 && sn[i-1] == '.')
-            sn[i-1] = 0;
-
-        if ((i = strlen(st)) > 0 && st[i-1] == '.')
-            st[i-1] = 0;
-
-        r->callback(r, r->interface, r->protocol, event, sn, st, r->domain_name, r->srv_record->data.srv.name, &a, r->srv_record->data.srv.port, r->txt_record->data.txt.string_list, r->userdata);
     }
 }
 
@@ -116,6 +151,8 @@ static void time_event_callback(AvahiTimeEvent *e, void *userdata) {
     assert(e);
     assert(r);
 
+    avahi_log_debug("timeout");
+    
     finish(r, AVAHI_RESOLVER_TIMEOUT);
 }
 
@@ -125,152 +162,237 @@ static void start_timeout(AvahiSServiceResolver *r) {
 
     if (r->time_event)
         return;
-    
+
     avahi_elapse_time(&tv, TIMEOUT_MSEC, 0);
+
     r->time_event = avahi_time_event_new(r->server->time_event_queue, &tv, time_event_callback, r);
 }
 
-static void record_browser_callback(AvahiSRecordBrowser*rr, AvahiIfIndex interface, AvahiProtocol protocol, AvahiBrowserEvent event, AvahiRecord *record, void* userdata) {
+static void record_browser_callback(
+    AvahiSRecordBrowser*rr,
+    AvahiIfIndex interface,
+    AvahiProtocol protocol,
+    AvahiBrowserEvent event,
+    AvahiRecord *record,
+    AvahiLookupResultFlags flags,
+    void* userdata) {
+    
     AvahiSServiceResolver *r = userdata;
 
     assert(rr);
-    assert(record);
     assert(r);
 
-    if (event == AVAHI_BROWSER_NEW) {
-        int changed = 0;
-
-        if (r->interface > 0 && interface != r->interface)
-            return;
-        
-        if (r->protocol != AVAHI_PROTO_UNSPEC && protocol != r->protocol)
-            return;
-        
-        if (r->interface <= 0)
-            r->interface = interface;
-        
-        if (r->protocol == AVAHI_PROTO_UNSPEC)
-            r->protocol = protocol;
-        
-        switch (record->key->type) {
-            case AVAHI_DNS_TYPE_SRV:
-                if (!r->srv_record) {
-                    r->srv_record = avahi_record_ref(record);
-                    changed = 1;
-
-                    if (r->record_browser_a) {
-                        avahi_s_record_browser_free(r->record_browser_a);
-                        r->record_browser_a = NULL;
+    if (rr == r->record_browser_aaaa || rr == r->record_browser_a)
+        r->address_flags = flags;
+    else if (rr == r->record_browser_srv)
+        r->srv_flags = flags;
+    else if (rr == r->record_browser_txt)
+        r->txt_flags = flags;
+
+    switch (event) {
+
+        case AVAHI_BROWSER_NEW: {
+            int changed = 0;
+            assert(record);
+            
+            if (r->interface > 0 && interface != r->interface)
+                return;
+            
+            if (r->protocol != AVAHI_PROTO_UNSPEC && protocol != r->protocol)
+                return;
+            
+            if (r->interface <= 0)
+                r->interface = interface;
+            
+            if (r->protocol == AVAHI_PROTO_UNSPEC)
+                r->protocol = protocol;
+            
+            switch (record->key->type) {
+                case AVAHI_DNS_TYPE_SRV:
+                    if (!r->srv_record) {
+                        r->srv_record = avahi_record_ref(record);
+                        changed = 1;
+                        
+                        if (r->record_browser_a) {
+                            avahi_s_record_browser_free(r->record_browser_a);
+                            r->record_browser_a = NULL;
+                        }
+                        
+                        if (r->record_browser_aaaa) {
+                            avahi_s_record_browser_free(r->record_browser_aaaa);
+                            r->record_browser_aaaa = NULL;
+                        }
+
+                        if (!(r->user_flags & AVAHI_LOOKUP_NO_ADDRESS)) {
+
+                            if (r->address_protocol == AVAHI_PROTO_INET || r->address_protocol == AVAHI_PROTO_UNSPEC) {
+                                AvahiKey *k = avahi_key_new(r->srv_record->data.srv.name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_A);
+                                r->record_browser_a = avahi_s_record_browser_new(r->server, r->interface, r->protocol, k, r->user_flags & ~(AVAHI_LOOKUP_NO_TXT|AVAHI_LOOKUP_NO_ADDRESS), record_browser_callback, r);
+                                avahi_key_unref(k);
+                            } 
+                        
+                            if (r->address_protocol == AVAHI_PROTO_INET6 || r->address_protocol == AVAHI_PROTO_UNSPEC) {
+                                AvahiKey *k = avahi_key_new(r->srv_record->data.srv.name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_AAAA);
+                                r->record_browser_aaaa = avahi_s_record_browser_new(r->server, r->interface, r->protocol, k, r->user_flags & ~(AVAHI_LOOKUP_NO_TXT|AVAHI_LOOKUP_NO_ADDRESS), record_browser_callback, r);
+                                avahi_key_unref(k);
+                            }
+                        }
                     }
+                    break;
+                
+                case AVAHI_DNS_TYPE_TXT:
 
-                    if (r->record_browser_aaaa) {
-                        avahi_s_record_browser_free(r->record_browser_aaaa);
-                        r->record_browser_aaaa = NULL;
-                    }
-                    
-                    if (r->address_protocol == AVAHI_PROTO_INET || r->address_protocol == AVAHI_PROTO_UNSPEC) {
-                        AvahiKey *k = avahi_key_new(r->srv_record->data.srv.name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_A);
-                        r->record_browser_a = avahi_s_record_browser_new(r->server, r->interface, r->protocol, k, record_browser_callback, r);
-                        avahi_key_unref(k);
-                    } 
-                    
-                    if (r->address_protocol == AVAHI_PROTO_INET6 || r->address_protocol == AVAHI_PROTO_UNSPEC) {
-                        AvahiKey *k = avahi_key_new(r->srv_record->data.srv.name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_AAAA);
-                        r->record_browser_aaaa = avahi_s_record_browser_new(r->server, r->interface, r->protocol, k, record_browser_callback, r);
-                        avahi_key_unref(k);
+                    assert(!(r->user_flags & AVAHI_LOOKUP_NO_TXT));
+
+                    if (!r->txt_record) {
+                        r->txt_record = avahi_record_ref(record);
+                        changed = 1;
                     }
-                }
-                break;
+                    break;
                 
-            case AVAHI_DNS_TYPE_TXT:
-                if (!r->txt_record) {
-                    r->txt_record = avahi_record_ref(record);
-                    changed = 1;
-                }
-                break;
-                
-            case AVAHI_DNS_TYPE_A:
-            case AVAHI_DNS_TYPE_AAAA:
-                if (!r->address_record) {
-                    r->address_record = avahi_record_ref(record);
-                    changed = 1;
-                }
-                break;
-                
-            default:
-                abort();
-        }
+                case AVAHI_DNS_TYPE_A:
+                case AVAHI_DNS_TYPE_AAAA:
 
+                    assert(!(r->user_flags & AVAHI_LOOKUP_NO_ADDRESS));
 
-        if (changed && r->txt_record && r->srv_record && r->address_record)
-            finish(r, AVAHI_RESOLVER_FOUND);
+                    if (!r->address_record) {
+                        r->address_record = avahi_record_ref(record);
+                        changed = 1;
+                    }
+                    break;
+                
+                default:
+                    abort();
+            }
 
-    } else {
-        assert(event == AVAHI_BROWSER_REMOVE);
 
-        
-        switch (record->key->type) {
-            case AVAHI_DNS_TYPE_SRV:
+            if (changed &&
+                r->srv_record &&
+                (r->txt_record || (r->user_flags & AVAHI_LOOKUP_NO_TXT)) &&
+                (r->address_record || (r->user_flags & AVAHI_LOOKUP_NO_ADDRESS)))
+                finish(r, AVAHI_RESOLVER_FOUND);
 
-                if (r->srv_record && avahi_record_equal_no_ttl(record, r->srv_record)) {
-                    avahi_record_unref(r->srv_record);
-                    r->srv_record = NULL;
+            break;
 
-                    /** Look for a replacement */
-                    avahi_s_record_browser_restart(r->record_browser_srv);
-                    start_timeout(r);
-                }
-                
-                break;
+        }
+            
+        case AVAHI_BROWSER_REMOVE:
 
-            case AVAHI_DNS_TYPE_TXT:
+            assert(record);
 
-                if (r->txt_record && avahi_record_equal_no_ttl(record, r->txt_record)) {
-                    avahi_record_unref(r->txt_record);
-                    r->txt_record = NULL;
+            switch (record->key->type) {
+                case AVAHI_DNS_TYPE_SRV:
+                    
+                    if (r->srv_record && avahi_record_equal_no_ttl(record, r->srv_record)) {
+                        avahi_record_unref(r->srv_record);
+                        r->srv_record = NULL;
+
+                        if (r->record_browser_a) {
+                            avahi_s_record_browser_free(r->record_browser_a);
+                            r->record_browser_a = NULL;
+                        }
+                        
+                        if (r->record_browser_aaaa) {
+                            avahi_s_record_browser_free(r->record_browser_aaaa);
+                            r->record_browser_aaaa = NULL;
+                        }
+                        
+                        /** Look for a replacement */
+                        avahi_s_record_browser_restart(r->record_browser_srv);
+                        start_timeout(r);
+                    }
+                    
+                    break;
+                    
+                case AVAHI_DNS_TYPE_TXT:
+                    
+                    assert(!(r->user_flags & AVAHI_LOOKUP_NO_TXT));
+                    
+                    if (r->txt_record && avahi_record_equal_no_ttl(record, r->txt_record)) {
+                        avahi_record_unref(r->txt_record);
+                        r->txt_record = NULL;
+                        
+                        /** Look for a replacement */
+                        avahi_s_record_browser_restart(r->record_browser_txt);
+                        start_timeout(r);
+                    }
+                    break;
+                    
+                case AVAHI_DNS_TYPE_A:
+                case AVAHI_DNS_TYPE_AAAA:
+                    
+                    assert(!(r->user_flags & AVAHI_LOOKUP_NO_ADDRESS));
+                    
+                    if (r->address_record && avahi_record_equal_no_ttl(record, r->address_record)) {
+                        avahi_record_unref(r->address_record);
+                        r->address_record = NULL;
+                        
+                        /** Look for a replacement */
+                        if (r->record_browser_aaaa)
+                            avahi_s_record_browser_restart(r->record_browser_aaaa);
+                        if (r->record_browser_a)
+                            avahi_s_record_browser_restart(r->record_browser_a);
+                        start_timeout(r);
+                    }
+                    break;
+                    
+                default:
+                    abort();
+            }
 
-                    /** Look for a replacement */
-                    avahi_s_record_browser_restart(r->record_browser_txt);
-                    start_timeout(r);
-                }
-                break;
+            break;
 
-            case AVAHI_DNS_TYPE_A:
-            case AVAHI_DNS_TYPE_AAAA:
+        case AVAHI_BROWSER_CACHE_EXHAUSTED:
+        case AVAHI_BROWSER_ALL_FOR_NOW:
+            break;
 
-                if (r->address_record && avahi_record_equal_no_ttl(record, r->address_record)) {
-                    avahi_record_unref(r->address_record);
-                    r->address_record = NULL;
+        case AVAHI_BROWSER_NOT_FOUND:
+        case AVAHI_BROWSER_FAILURE:
 
-                    /** Look for a replacement */
-                    if (r->record_browser_aaaa)
-                        avahi_s_record_browser_restart(r->record_browser_aaaa);
-                    if (r->record_browser_a)
-                        avahi_s_record_browser_restart(r->record_browser_a);
-                    start_timeout(r);
-                }
-                break;
+            if (r->record_browser_srv)
+                avahi_s_record_browser_free(r->record_browser_srv);
+            if (r->record_browser_txt)
+                avahi_s_record_browser_free(r->record_browser_txt);
+            if (r->record_browser_a)
+                avahi_s_record_browser_free(r->record_browser_a);
+            if (r->record_browser_aaaa)
+                avahi_s_record_browser_free(r->record_browser_aaaa);
 
-            default:
-                abort();
-        }
+            r->record_browser_srv = r->record_browser_txt = r->record_browser_a = r->record_browser_aaaa = NULL;
+
+            finish(r, event == AVAHI_BROWSER_FAILURE ? AVAHI_RESOLVER_FAILURE : AVAHI_RESOLVER_NOT_FOUND);
+            break;
     }
 }
 
-AvahiSServiceResolver *avahi_s_service_resolver_new(AvahiServer *server, AvahiIfIndex interface, AvahiProtocol protocol, const char *name, const char *type, const char *domain, AvahiProtocol aprotocol, AvahiSServiceResolverCallback callback, void* userdata) {
+AvahiSServiceResolver *avahi_s_service_resolver_new(
+    AvahiServer *server,
+    AvahiIfIndex interface,
+    AvahiProtocol protocol,
+    const char *name,
+    const char *type,
+    const char *domain,
+    AvahiProtocol aprotocol,
+    AvahiLookupFlags flags,
+    AvahiSServiceResolverCallback callback,
+    void* userdata) {
+    
     AvahiSServiceResolver *r;
     AvahiKey *k;
-    char t[256], *n;
-    size_t l;
+    char t[256];
     
     assert(server);
-    assert(name);
     assert(type);
     assert(callback);
 
     assert(aprotocol == AVAHI_PROTO_UNSPEC || aprotocol == AVAHI_PROTO_INET || aprotocol == AVAHI_PROTO_INET6);
 
-    if (!avahi_is_valid_service_name(name)) {
+    if (!AVAHI_IF_VALID(interface)) {
+        avahi_server_set_errno(server, AVAHI_ERR_INVALID_INTERFACE);
+        return NULL;
+    }
+
+    if (name && !avahi_is_valid_service_name(name)) {
         avahi_server_set_errno(server, AVAHI_ERR_INVALID_SERVICE_NAME);
         return NULL;
     }
@@ -280,10 +402,18 @@ AvahiSServiceResolver *avahi_s_service_resolver_new(AvahiServer *server, AvahiIf
         return NULL;
     }
 
-    if (!avahi_is_valid_domain_name(domain)) {
+    if (domain && !avahi_is_valid_domain_name(domain)) {
         avahi_server_set_errno(server, AVAHI_ERR_INVALID_DOMAIN_NAME);
         return NULL;
     }
+
+    if (!domain)
+        domain = server->domain_name;
+    
+    if (!AVAHI_VALID_FLAGS(flags, AVAHI_LOOKUP_USE_WIDE_AREA|AVAHI_LOOKUP_USE_MULTICAST|AVAHI_LOOKUP_NO_TXT|AVAHI_LOOKUP_NO_ADDRESS)) {
+        avahi_server_set_errno(server, AVAHI_ERR_INVALID_FLAGS);
+        return NULL;
+    }
     
     if (!(r = avahi_new(AvahiSServiceResolver, 1))) {
         avahi_server_set_errno(server, AVAHI_ERR_NO_MEMORY);
@@ -298,39 +428,50 @@ AvahiSServiceResolver *avahi_s_service_resolver_new(AvahiServer *server, AvahiIf
     r->userdata = userdata;
     r->address_protocol = aprotocol;
     r->srv_record = r->txt_record = r->address_record = NULL;
+    r->srv_flags = r->txt_flags = r->address_flags = 0;
     r->interface = interface;
     r->protocol = protocol;
-    
-    n = t;
-    l = sizeof(t);
-    avahi_escape_label((const uint8_t*) name, strlen(name), &n, &l);
-    snprintf(n, l, ".%s.%s", r->service_type, r->domain_name);
+    r->user_flags = flags;
+
+    if (name) {
+        char *n;
+        size_t l;
+
+        n = t;
+        l = sizeof(t);
+        avahi_escape_label((const uint8_t*) name, strlen(name), &n, &l);
+        snprintf(n, l, ".%s.%s", r->service_type, r->domain_name);
+    } else
+        snprintf(t, sizeof(t), "%s.%s", r->service_type, r->domain_name);
 
     r->time_event = NULL;
-    start_timeout(r);
     
     AVAHI_LLIST_PREPEND(AvahiSServiceResolver, resolver, server->service_resolvers, r);
 
     r->record_browser_a = r->record_browser_aaaa = r->record_browser_srv = r->record_browser_txt = NULL;
     
     k = avahi_key_new(t, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV);
-    r->record_browser_srv = avahi_s_record_browser_new(server, interface, protocol, k, record_browser_callback, r);
+    r->record_browser_srv = avahi_s_record_browser_new(server, interface, protocol, k, flags & ~(AVAHI_LOOKUP_NO_TXT|AVAHI_LOOKUP_NO_ADDRESS), record_browser_callback, r);
     avahi_key_unref(k);
 
     if (!r->record_browser_srv) {
         avahi_s_service_resolver_free(r);
         return NULL;
     }
-    
-    k = avahi_key_new(t, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_TXT);
-    r->record_browser_txt = avahi_s_record_browser_new(server, interface, protocol, k, record_browser_callback, r);
-    avahi_key_unref(k);
 
-    if (!r->record_browser_txt) {
-        avahi_s_service_resolver_free(r);
-        return NULL;
+    if (!(flags & AVAHI_LOOKUP_NO_TXT)) {
+        k = avahi_key_new(t, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_TXT);
+        r->record_browser_txt = avahi_s_record_browser_new(server, interface, protocol, k, flags & ~(AVAHI_LOOKUP_NO_TXT|AVAHI_LOOKUP_NO_ADDRESS),  record_browser_callback, r);
+        avahi_key_unref(k);
+        
+        if (!r->record_browser_txt) {
+            avahi_s_service_resolver_free(r);
+            return NULL;
+        }
     }
 
+    start_timeout(r);
+    
     return r;
 }