* detect other running mDNS stacks

* replace more g_message()/g_warning() calls with avahi_log_xxx()
* fix configuration file paths
* only load configuration file when running daemon
* require uid == 0
* fix static service reloading
* add new command line option for reloading -r


git-svn-id: file:///home/lennart/svn/public/avahi/trunk@129 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe

5 files changed, 119 insertions, 51 deletions

diff --git a/avahi-core/server.c b/avahi-core/server.c
index d03a284..86f29fb 100644
--- a/avahi-core/server.c
+++ b/avahi-core/server.c
@@ -1268,14 +1268,14 @@ AvahiServer *avahi_server_new(GMainContext *c, const AvahiServerConfig *sc, Avah
     }
 
     if (s->fd_ipv4 < 0 && s->config.use_ipv4)
-        avahi_log_debug("Failed to create IPv4 socket, proceeding in IPv6 only mode");
+        avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode");
     else if (s->fd_ipv6 < 0 && s->config.use_ipv6)
-        avahi_log_debug("Failed to create IPv6 socket, proceeding in IPv4 only mode");
+        avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode");
 
     s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_legacy_unicast_socket_ipv4() : -1;
     s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_legacy_unicast_socket_ipv6() : -1;
 
-    g_main_context_ref(c->context = c ? c : g_main_context_default());
+    g_main_context_ref(s->context = (c ? c : g_main_context_default()));
 
     /* Prepare IO source registration */
     s->source = g_source_new(&source_funcs, sizeof(GSource) + sizeof(AvahiServer*));
diff --git a/avahi-core/socket.c b/avahi-core/socket.c
index 55db704..8f3d896 100644
--- a/avahi-core/socket.c
+++ b/avahi-core/socket.c
@@ -156,6 +156,50 @@ int avahi_mdns_mcast_leave_ipv6 (int index, int fd) {
     return 0;
 }
 
+static gint bind_with_warn(int fd, const struct sockaddr *sa, socklen_t l) {
+    gint yes;
+    
+    g_assert(fd >= 0);
+    g_assert(sa);
+    g_assert(l > 0);
+    
+    if (bind(fd, sa, l) < 0) {
+
+        if (errno != EADDRINUSE) {
+            avahi_log_warn("bind() failed: %s\n", strerror(errno));
+            return -1;
+        }
+            
+        avahi_log_warn("*** WARNING: Detected another %s mDNS stack running on this host. This makes mDNS unreliable and is thus not recommended. ***",
+                       sa->sa_family == AF_INET ? "IPv4" : "IPv6");
+
+        /* Try again, this time with SO_REUSEADDR set */
+        yes = 1;
+        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
+            avahi_log_warn("SO_REUSEADDR failed: %s\n", strerror(errno));
+            return -1;
+        }
+
+        if (bind(fd, sa, l) < 0) {
+            avahi_log_warn("bind() failed: %s\n", strerror(errno));
+            return -1;
+        }
+    } else {
+
+        /* We enable SO_REUSEADDR afterwards, to make sure that the
+         * user may run other mDNS implementations if he really
+         * wants. */
+        
+        yes = 1;
+        if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
+            avahi_log_warn("SO_REUSEADDR failed: %s\n", strerror(errno));
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
 gint avahi_open_socket_ipv4(void) {
     struct sockaddr_in local;
     int fd = -1, ttl, yes;
@@ -178,26 +222,17 @@ gint avahi_open_socket_ipv4(void) {
     }
     
     yes = 1;
-    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
-        avahi_log_warn("SO_REUSEADDR failed: %s\n", strerror(errno));
-        goto fail;
-    }
-
-    yes = 1;
     if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP, &yes, sizeof(yes)) < 0) {
         avahi_log_warn("IP_MULTICAST_LOOP failed: %s\n", strerror(errno));
         goto fail;
     }
-
     
     memset(&local, 0, sizeof(local));
     local.sin_family = AF_INET;
     local.sin_port = htons(AVAHI_MDNS_PORT);
-    
-    if (bind(fd, (struct sockaddr*) &local, sizeof(local)) < 0) {
-        avahi_log_warn("bind() failed: %s\n", strerror(errno));
+
+    if (bind_with_warn(fd, (struct sockaddr*) &local, sizeof(local)) < 0)
         goto fail;
-    }
 
     yes = 1;
     if (setsockopt(fd, SOL_IP, IP_RECVTTL, &yes, sizeof(yes)) < 0) {
@@ -254,12 +289,6 @@ gint avahi_open_socket_ipv6(void) {
     }
     
     yes = 1;
-    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
-        avahi_log_warn("SO_REUSEADDR failed: %s\n", strerror(errno));
-        goto fail;
-    }
-
-    yes = 1;
     if (setsockopt(fd, SOL_IPV6, IPV6_V6ONLY, &yes, sizeof(yes)) < 0) {
         avahi_log_warn("IPV6_V6ONLY failed: %s\n", strerror(errno));
         goto fail;
@@ -275,10 +304,8 @@ gint avahi_open_socket_ipv6(void) {
     local.sin6_family = AF_INET6;
     local.sin6_port = htons(AVAHI_MDNS_PORT);
     
-    if (bind(fd, (struct sockaddr*) &local, sizeof(local)) < 0) {
-        avahi_log_warn("bind() failed: %s\n", strerror(errno));
+    if (bind_with_warn(fd, (struct sockaddr*) &local, sizeof(local)) < 0)
         goto fail;
-    }
 
     yes = 1;
     if (setsockopt(fd, SOL_IPV6, IPV6_HOPLIMIT, &yes, sizeof(yes)) < 0) {
diff --git a/avahi-daemon/Makefile.am b/avahi-daemon/Makefile.am
index bb983a3..5f561db 100644
--- a/avahi-daemon/Makefile.am
+++ b/avahi-daemon/Makefile.am
@@ -17,7 +17,14 @@
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 # USA.
 
-AM_CFLAGS=-I$(top_srcdir) -D_GNU_SOURCE -DAVAHI_SERVICE_DIRECTORY=\"`pwd`\" -DAVAHI_CONFIG_FILE=\"avahi.conf\"
+pkgsysconfdir=$(sysconfdir)/avahi
+servicedir=$(pkgsysconfdir)/services
+
+AM_CFLAGS= \
+	-I$(top_srcdir) \
+	-D_GNU_SOURCE \
+	-DAVAHI_SERVICE_DIRECTORY=\"$(servicedir)\" \
+	-DAVAHI_CONFIG_FILE=\"$(pkgsysconfdir)/avahi.conf\"
 AM_LDADD=-lexpat
 
 # GLIB 2.0
@@ -46,6 +53,15 @@ avahi_SOURCES = \
 	simple-protocol.c simple-protocol.h \
 	static-services.c static-services.h
 
+pkgsysconf_DATA = \
+	avahi.conf
+
+service_DATA = \
+	example.service
+
+pkgdata_DATA = \
+	avahi-service.dtd
+
 if ENABLE_DBUS
 avahi_SOURCES += dbus-protocol.c dbus-protocol.h
 endif
diff --git a/avahi-daemon/main.c b/avahi-daemon/main.c
index 0d862ea..ec76114 100644
--- a/avahi-daemon/main.c
+++ b/avahi-daemon/main.c
@@ -28,6 +28,7 @@
 #include <signal.h>
 #include <errno.h>
 #include <string.h>
+#include <unistd.h>
 
 #include <libdaemon/dfork.h>
 #include <libdaemon/dsignal.h>
@@ -48,7 +49,8 @@ typedef enum {
     DAEMON_RUN,
     DAEMON_KILL,
     DAEMON_VERSION,
-    DAEMON_HELP
+    DAEMON_HELP,
+    DAEMON_RELOAD
 } DaemonCommand;
 
 typedef struct {
@@ -83,8 +85,10 @@ static void help(FILE *f, const gchar *argv0) {
             "    -h --help        Show this help\n"
             "    -D --daemonize   Daemonize after startup\n"
             "    -k --kill        Kill a running daemon\n"
+            "    -r --reload      Request a running daemon to reload static services\n"
             "    -V --version     Show version\n"
-            "    -f --file=FILE   Load the specified configuration file instead of the default\n",
+            "    -f --file=FILE   Load the specified configuration file instead of\n"
+            "                     "AVAHI_CONFIG_FILE"\n",
             argv0);
 }
 
@@ -97,12 +101,13 @@ static gint parse_command_line(DaemonConfig *config, int argc, char *argv[]) {
         { "kill",      no_argument,       NULL, 'k' },
         { "version",   no_argument,       NULL, 'V' },
         { "file",      required_argument, NULL, 'f' },
+        { "reload",    no_argument,       NULL, 'r' },
     };
 
     g_assert(config);
 
     opterr = 0;
-    while ((c = getopt_long(argc, argv, "hDkVf:", long_options, NULL)) >= 0) {
+    while ((c = getopt_long(argc, argv, "hDkVf:r", long_options, NULL)) >= 0) {
 
         switch(c) {
             case 'h':
@@ -121,6 +126,9 @@ static gint parse_command_line(DaemonConfig *config, int argc, char *argv[]) {
                 g_free(config->config_file);
                 config->config_file = g_strdup(optarg);
                 break;
+            case 'r':
+                config->command = DAEMON_RELOAD;
+                break;
             default:
                 fprintf(stderr, "Invalid command line argument: %c\n", c);
                 return -1;
@@ -314,6 +322,7 @@ static gboolean signal_callback(GIOChannel *source, GIOCondition condition, gpoi
         case SIGHUP:
             avahi_log_info("Got SIGHUP, reloading.");
             static_service_load();
+            static_service_add_to_server();
             break;
 
         default:
@@ -425,9 +434,6 @@ int main(int argc, char *argv[]) {
     if (parse_command_line(&config, argc, argv) < 0)
         goto finish;
 
-    if (load_config_file(&config) < 0)
-        goto finish;
-
     if (config.command == DAEMON_HELP) {
         help(stdout, argv0);
         r = 0;
@@ -442,14 +448,30 @@ int main(int argc, char *argv[]) {
 
         r = 0;
         
+    } else if (config.command == DAEMON_RELOAD) {
+        if (daemon_pid_file_kill(SIGHUP) < 0) {
+            avahi_log_warn("Failed to kill daemon: %s", strerror(errno));
+            goto finish;
+        }
+
+        r = 0;
+        
     } else if (config.command == DAEMON_RUN) {
         pid_t pid;
+
+        if (getuid() != 0) {
+            avahi_log_error("This program is intended to be run as root.");
+            goto finish;
+        }
         
         if ((pid = daemon_pid_file_is_running()) >= 0) {
             avahi_log_error("Daemon already running on PID %u", pid);
             goto finish;
         }
 
+        if (load_config_file(&config) < 0)
+            goto finish;
+        
         if (config.daemonize) {
 
             daemon_retval_init();
diff --git a/avahi-daemon/static-services.c b/avahi-daemon/static-services.c
index 8148de4..898edf3 100644
--- a/avahi-daemon/static-services.c
+++ b/avahi-daemon/static-services.c
@@ -35,6 +35,7 @@
 #include <expat.h>
 
 #include <avahi-core/llist.h>
+#include <avahi-core/log.h>
 
 #include "main.h"
 
@@ -178,11 +179,11 @@ static void entry_group_callback(AvahiServer *s, AvahiEntryGroup *eg, AvahiEntry
         g_free(g->chosen_name);
         g->chosen_name = n;
 
-        g_message("Service name conflict for \"%s\" (%s), retrying with \"%s\".", g->name, g->filename, g->chosen_name);
+        avahi_log_notice("Service name conflict for \"%s\" (%s), retrying with \"%s\".", g->name, g->filename, g->chosen_name);
 
         add_static_service_group_to_server(g);
-    } else
-        g_message("Service \"%s\" (%s) successfully establised.", g->chosen_name, g->filename);
+    } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED)
+        avahi_log_info("Service \"%s\" (%s) successfully established.", g->chosen_name, g->filename);
 }
 
 static void add_static_service_group_to_server(StaticServiceGroup *g) {
@@ -212,7 +213,7 @@ static void add_static_service_group_to_server(StaticServiceGroup *g) {
                 s->type, g->chosen_name,
                 s->domain_name, s->host_name, s->port,
                 avahi_string_list_copy(s->txt_records)) < 0) {
-            g_message("Failed to add service '%s' of type '%s', ignoring service group (%s)", g->chosen_name, s->type, g->filename);
+            avahi_log_error("Failed to add service '%s' of type '%s', ignoring service group (%s)", g->chosen_name, s->type, g->filename);
             remove_static_service_group_from_server(g);
             return;
         }
@@ -313,14 +314,14 @@ static void XMLCALL xml_start(void *data, const char *el, const char *attr[]) {
         
         u->current_tag = XML_TAG_TXT_RECORD;
     } else {
-        g_message("%s: parse failure: didn't expect element <%s>.", u->group->filename, el);
+        avahi_log_error("%s: parse failure: didn't expect element <%s>.", u->group->filename, el);
         u->failed = TRUE;
     }
 
     return;
 
 invalid_attr:
-    g_message("%s: parse failure: invalid attribute for element <%s>.", u->group->filename, el);
+    avahi_log_error("%s: parse failure: invalid attribute for element <%s>.", u->group->filename, el);
     u->failed = TRUE;
     return;
 }
@@ -336,7 +337,7 @@ static void XMLCALL xml_end(void *data, const char *el) {
         case XML_TAG_SERVICE_GROUP:
 
             if (!u->group->name || !u->group->services) {
-                g_message("%s: parse failure: service group incomplete.", u->group->filename);
+                avahi_log_error("%s: parse failure: service group incomplete.", u->group->filename);
                 u->failed = TRUE;
                 return;
             }
@@ -347,7 +348,7 @@ static void XMLCALL xml_end(void *data, const char *el) {
         case XML_TAG_SERVICE:
 
             if (u->service->port == 0 || !u->service->type) {
-                g_message("%s: parse failure: service incomplete.", u->group->filename);
+                avahi_log_error("%s: parse failure: service incomplete.", u->group->filename);
                 u->failed = TRUE;
                 return;
             }
@@ -367,7 +368,7 @@ static void XMLCALL xml_end(void *data, const char *el) {
             p = u->buf ? atoi(u->buf) : 0;
 
             if (p <= 0 || p > 0xFFFF) {
-                g_message("%s: parse failure: invalid port specification \"%s\".", u->group->filename, u->buf);
+                avahi_log_error("%s: parse failure: invalid port specification \"%s\".", u->group->filename, u->buf);
                 u->failed = TRUE;
                 return;
             }
@@ -484,17 +485,17 @@ static gint static_service_group_load(StaticServiceGroup *g) {
     g->replace_wildcards = FALSE;
     
     if (!(parser = XML_ParserCreate(NULL))) {
-        g_warning("XML_ParserCreate() failed.");
+        avahi_log_error("XML_ParserCreate() failed.");
         goto finish;
     }
 
     if ((fd = open(g->filename, O_RDONLY)) < 0) {
-        g_warning("open(\"%s\", O_RDONLY): %s", g->filename, strerror(errno));
+        avahi_log_error("open(\"%s\", O_RDONLY): %s", g->filename, strerror(errno));
         goto finish;
     }
 
     if (fstat(fd, &st) < 0) {
-        g_warning("fstat(): %s", strerror(errno));
+        avahi_log_error("fstat(): %s", strerror(errno));
         goto finish;
     }
 
@@ -511,17 +512,17 @@ static gint static_service_group_load(StaticServiceGroup *g) {
 #define BUFSIZE (10*1024)
 
         if (!(buffer = XML_GetBuffer(parser, BUFSIZE))) {
-            g_warning("XML_GetBuffer() failed.");
+            avahi_log_error("XML_GetBuffer() failed.");
             goto finish;
         }
 
         if ((n = read(fd, buffer, BUFSIZE)) < 0) {
-            g_warning("read(): %s\n", strerror(errno));
+            avahi_log_error("read(): %s\n", strerror(errno));
             goto finish;
         }
 
         if (!XML_ParseBuffer(parser, n, n == 0)) {
-            g_warning("XML_ParseBuffer() failed at line %d: %s.\n", XML_GetCurrentLineNumber(parser), XML_ErrorString(XML_GetErrorCode(parser)));
+            avahi_log_error("XML_ParseBuffer() failed at line %d: %s.\n", XML_GetCurrentLineNumber(parser), XML_ErrorString(XML_GetErrorCode(parser)));
             goto finish;
         }
 
@@ -551,9 +552,11 @@ static void load_file(gchar *n) {
         if (strcmp(g->filename, n) == 0)
             return;
 
+    avahi_log_info("Loading service file %s", n);
+    
     g = static_service_group_new(n);
     if (static_service_group_load(g) < 0) {
-        g_warning("Failed to load service group file %s, ignoring.", g->filename);
+        avahi_log_error("Failed to load service group file %s, ignoring.", g->filename);
         static_service_group_free(g);
     }
 }
@@ -571,16 +574,16 @@ void static_service_load(void) {
         if (stat(g->filename, &st) < 0) {
 
             if (errno == ENOENT)
-                g_message("Service group file %s vanished, removing seervices.", g->filename);
+                avahi_log_info("Service group file %s vanished, removing services.", g->filename);
             else
-                g_warning("Failed to stat() file %s, ignoring: %s", g->filename, strerror(errno));
+                avahi_log_warn("Failed to stat() file %s, ignoring: %s", g->filename, strerror(errno));
             
             static_service_group_free(g);
         } else if (st.st_mtime != g->mtime) {
-            g_message("Service group file %s changed, reloading.", g->filename);
+            avahi_log_info("Service group file %s changed, reloading.", g->filename);
             
             if (static_service_group_load(g) < 0) {
-                g_warning("Failed to load service group file %s, removing service.", g->filename);
+                avahi_log_warn("Failed to load service group file %s, removing service.", g->filename);
                 static_service_group_free(g);
             }
         }
@@ -588,7 +591,7 @@ void static_service_load(void) {
 
     memset(&globbuf, 0, sizeof(globbuf));
     if (glob(AVAHI_SERVICE_DIRECTORY "/*.service", GLOB_ERR, NULL, &globbuf) != 0)
-        g_warning("glob() failed.\n");
+        avahi_log_error("glob() failed.\n");
     else {
         for (p = globbuf.gl_pathv; *p; p++)
             load_file(*p);