From 238909aaff10489fe538c8c54e3f82fe8a54b849 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 2 Jun 2010 04:37:40 +0200 Subject: systemd: add support for acquiring socket from systemd --- avahi-daemon/simple-protocol.c | 127 ++++++++++++++++++++++++----------------- 1 file changed, 75 insertions(+), 52 deletions(-) (limited to 'avahi-daemon/simple-protocol.c') diff --git a/avahi-daemon/simple-protocol.c b/avahi-daemon/simple-protocol.c index 33e5db3..ffe079f 100644 --- a/avahi-daemon/simple-protocol.c +++ b/avahi-daemon/simple-protocol.c @@ -2,17 +2,17 @@ /*** This file is part of avahi. - + avahi is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. - + avahi is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. - + You should have received a copy of the GNU Lesser General Public License along with avahi; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 @@ -44,6 +44,7 @@ #include "simple-protocol.h" #include "main.h" +#include "sd-daemon.h" #ifdef ENABLE_CHROOT #include "chroot.h" @@ -75,7 +76,7 @@ struct Client { Server *server; ClientState state; - + int fd; AvahiWatch *watch; @@ -87,7 +88,7 @@ struct Client { AvahiSDNSServerBrowser *dns_server_browser; AvahiProtocol afquery; - + AVAHI_LLIST_FIELDS(Client, clients); }; @@ -98,7 +99,7 @@ struct Server { AVAHI_LLIST_HEAD(Client, clients); unsigned n_clients; - int bind_successful; + int remove_socket; }; static Server *server = NULL; @@ -122,7 +123,7 @@ static void client_free(Client *c) { c->server->poll_api->watch_free(c->watch); close(c->fd); - + AVAHI_LLIST_REMOVE(Client, clients, c->server->clients, c); avahi_free(c); } @@ -151,7 +152,7 @@ static void client_new(Server *s, int fd) { static void client_output(Client *c, const uint8_t*data, size_t size) { size_t k, m; - + assert(c); assert(data); @@ -170,7 +171,7 @@ static void client_output(Client *c, const uint8_t*data, size_t size) { static void client_output_printf(Client *c, const char *format, ...) { char *t; va_list ap; - + va_start(ap, format); t = avahi_strdup_vprintf(format, ap); va_end(ap); @@ -186,11 +187,11 @@ static void host_name_resolver_callback( AvahiResolverEvent event, const char *hostname, const AvahiAddress *a, - AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, + AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, void* userdata) { Client *c = userdata; - + assert(c); if (event == AVAHI_RESOLVER_FAILURE) @@ -213,9 +214,9 @@ static void address_resolver_callback( const char *hostname, AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, void* userdata) { - + Client *c = userdata; - + assert(c); if (event == AVAHI_RESOLVER_FAILURE) @@ -236,10 +237,10 @@ static void dns_server_browser_callback( uint16_t port, AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, void* userdata) { - + Client *c = userdata; char t[AVAHI_ADDRESS_STR_MAX]; - + assert(c); if (!a) @@ -257,7 +258,7 @@ static void dns_server_browser_callback( case AVAHI_BROWSER_NEW: case AVAHI_BROWSER_REMOVE: - + avahi_address_snprint(t, sizeof(t), a); client_output_printf(c, "%c %i %u %s %u\n", event == AVAHI_BROWSER_NEW ? '>' : '<', interface, protocol, t, port); break; @@ -314,7 +315,7 @@ static void handle_line(Client *c, const char *s) { avahi_log_debug(__FILE__": Got %s request for '%s'.", cmd, arg); } else if (strcmp(cmd, "RESOLVE-ADDRESS") == 0 && n_args == 2) { AvahiAddress addr; - + if (!(avahi_address_parse(arg, AVAHI_PROTO_UNSPEC, &addr))) { client_output_printf(c, "%+i Failed to parse address \"%s\".\n", AVAHI_ERR_INVALID_ADDRESS, arg); c->state = CLIENT_DEAD; @@ -376,7 +377,7 @@ static void handle_input(Client *c) { k = e - (char*) c->inbuf; *e = 0; - + handle_line(c, c->inbuf); c->inbuf_length -= k + 1; memmove(c->inbuf, e+1, c->inbuf_length); @@ -390,7 +391,7 @@ static void client_work(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AvahiWatchEv if ((events & AVAHI_WATCH_IN) && c->inbuf_length < sizeof(c->inbuf)) { ssize_t r; - + if ((r = read(c->fd, c->inbuf + c->inbuf_length, sizeof(c->inbuf) - c->inbuf_length)) <= 0) { if (r < 0) avahi_log_warn("read(): %s", strerror(errno)); @@ -415,7 +416,7 @@ static void client_work(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AvahiWatchEv assert((size_t) r <= c->outbuf_length); c->outbuf_length -= r; - + if (c->outbuf_length) memmove(c->outbuf, c->outbuf + r, c->outbuf_length - r); @@ -426,7 +427,7 @@ static void client_work(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AvahiWatchEv } c->server->poll_api->watch_update( - watch, + watch, (c->outbuf_length > 0 ? AVAHI_WATCH_OUT : 0) | (c->inbuf_length < sizeof(c->inbuf) ? AVAHI_WATCH_IN : 0)); } @@ -445,59 +446,83 @@ static void server_work(AVAHI_GCC_UNUSED AvahiWatch *watch, int fd, AvahiWatchEv client_new(s, cfd); } } - + int simple_protocol_setup(const AvahiPoll *poll_api) { struct sockaddr_un sa; mode_t u; + int n; assert(!server); server = avahi_new(Server, 1); server->poll_api = poll_api; - server->bind_successful = 0; + server->remove_socket = 0; server->fd = -1; server->n_clients = 0; AVAHI_LLIST_HEAD_INIT(Client, server->clients); server->watch = NULL; - + u = umask(0000); - if ((server->fd = socket(PF_LOCAL, SOCK_STREAM, 0)) < 0) { - avahi_log_warn("socket(PF_LOCAL, SOCK_STREAM, 0): %s", strerror(errno)); + if ((n = sd_listen_fds(1)) < 0) { + avahi_log_warn("Failed to acquire systemd file descriptors: %s", strerror(-n)); goto fail; } - memset(&sa, 0, sizeof(sa)); - sa.sun_family = AF_LOCAL; - strncpy(sa.sun_path, AVAHI_SOCKET, sizeof(sa.sun_path)-1); - - /* We simply remove existing UNIX sockets under this name. The - Avahi daemon makes sure that it runs only once on a host, - therefore sockets that already exist are stale and may be - removed without any ill effects */ - - unlink(AVAHI_SOCKET); - - if (bind(server->fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) { - avahi_log_warn("bind(): %s", strerror(errno)); + if (n > 1) { + avahi_log_warn("Too many systemd file descriptors passed."); goto fail; } - server->bind_successful = 1; - - if (listen(server->fd, 2) < 0) { - avahi_log_warn("listen(): %s", strerror(errno)); - goto fail; + if (n == 1) { + int r; + + if ((r = sd_is_socket(AF_LOCAL, SOCK_STREAM, 1, 0)) < 0) { + avahi_log_warn("Passed systemd file descriptor is of wrong type: %s", strerror(-r)); + goto fail; + } + + server->fd = SD_LISTEN_FDS_START; + + } else { + + if ((server->fd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) { + avahi_log_warn("socket(AF_LOCAL, SOCK_STREAM, 0): %s", strerror(errno)); + goto fail; + } + + memset(&sa, 0, sizeof(sa)); + sa.sun_family = AF_LOCAL; + strncpy(sa.sun_path, AVAHI_SOCKET, sizeof(sa.sun_path)-1); + + /* We simply remove existing UNIX sockets under this name. The + Avahi daemon makes sure that it runs only once on a host, + therefore sockets that already exist are stale and may be + removed without any ill effects */ + + unlink(AVAHI_SOCKET); + + if (bind(server->fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) { + avahi_log_warn("bind(): %s", strerror(errno)); + goto fail; + } + + server->remove_socket = 1; + + if (listen(server->fd, SOMAXCONN) < 0) { + avahi_log_warn("listen(): %s", strerror(errno)); + goto fail; + } } umask(u); server->watch = poll_api->watch_new(poll_api, server->fd, AVAHI_WATCH_IN, server_work, server); - + return 0; fail: - + umask(u); simple_protocol_shutdown(); @@ -508,7 +533,7 @@ void simple_protocol_shutdown(void) { if (server) { - if (server->bind_successful) + if (server->remove_socket) #ifdef ENABLE_CHROOT avahi_chroot_helper_unlink(AVAHI_SOCKET); #else @@ -520,12 +545,12 @@ void simple_protocol_shutdown(void) { if (server->watch) server->poll_api->watch_free(server->watch); - + if (server->fd >= 0) close(server->fd); avahi_free(server); - + server = NULL; } } @@ -534,7 +559,7 @@ void simple_protocol_restart_queries(void) { Client *c; /* Restart queries in case of local domain name changes */ - + assert(server); for (c = server->clients; c; c = c->clients_next) @@ -543,5 +568,3 @@ void simple_protocol_restart_queries(void) { c->dns_server_browser = avahi_s_dns_server_browser_new(avahi_server, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, NULL, AVAHI_DNS_SERVER_RESOLVE, c->afquery, AVAHI_LOOKUP_USE_MULTICAST, dns_server_browser_callback, c); } } - - -- cgit