From: Lennart Poettering Date: Sun, 15 Apr 2007 00:34:30 +0000 (+0000) Subject: Add inotify support for /ect/avahi/services and /etc/avahi/hosts. Based on a patch... X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=6bebc22419959153a45c7640fd7c263d448bc948;p=catta Add inotify support for /ect/avahi/services and /etc/avahi/hosts. Based on a patch from "behanw". (Closes #95, #33) git-svn-id: file:///home/lennart/svn/public/avahi/trunk@1426 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe --- diff --git a/avahi-daemon/inotify-nosys.h b/avahi-daemon/inotify-nosys.h new file mode 100644 index 0000000..6af44dc --- /dev/null +++ b/avahi-daemon/inotify-nosys.h @@ -0,0 +1,181 @@ +/* + * This header is used if cannot be found. + * + * Inode based directory notification for Linux + * + * Copyright (C) 2005 John McCutchan + */ + +#ifndef _LINUX_INOTIFY_H +#define _LINUX_INOTIFY_H + +#include +#include +#include +#include + +/* + * struct inotify_event - structure read from the inotify device for each event + * + * When you are watching a directory, you will receive the filename for events + * such as IN_CREATE, IN_DELETE, IN_OPEN, IN_CLOSE, ..., relative to the wd. + */ +struct inotify_event { + int wd; /* watch descriptor */ + uint32_t mask; /* watch mask */ + uint32_t cookie; /* cookie to synchronize two events */ + uint32_t len; /* length (including nulls) of name */ + char name __flexarr; /* stub for possible name */ +}; + +/* the following are legal, implemented events that user-space can watch for */ +#define IN_ACCESS 0x00000001 /* File was accessed */ +#define IN_MODIFY 0x00000002 /* File was modified */ +#define IN_ATTRIB 0x00000004 /* Metadata changed */ +#define IN_CLOSE_WRITE 0x00000008 /* Writtable file was closed */ +#define IN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */ +#define IN_OPEN 0x00000020 /* File was opened */ +#define IN_MOVED_FROM 0x00000040 /* File was moved from X */ +#define IN_MOVED_TO 0x00000080 /* File was moved to Y */ +#define IN_CREATE 0x00000100 /* Subfile was created */ +#define IN_DELETE 0x00000200 /* Subfile was deleted */ +#define IN_DELETE_SELF 0x00000400 /* Self was deleted */ +#define IN_MOVE_SELF 0x00000800 /* Self was moved */ + +/* the following are legal events. they are sent as needed to any watch */ +#define IN_UNMOUNT 0x00002000 /* Backing fs was unmounted */ +#define IN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ +#define IN_IGNORED 0x00008000 /* File was ignored */ + +/* helper events */ +#define IN_CLOSE (IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) /* close */ +#define IN_MOVE (IN_MOVED_FROM | IN_MOVED_TO) /* moves */ + +/* special flags */ +#define IN_ONLYDIR 0x01000000 /* only watch the path if it is a directory */ +#define IN_DONT_FOLLOW 0x02000000 /* don't follow a sym link */ +#define IN_MASK_ADD 0x20000000 /* add to the mask of an already existing watch */ +#define IN_ISDIR 0x40000000 /* event occurred against dir */ +#define IN_ONESHOT 0x80000000 /* only send event once */ + +/* + * All of the events - we build the list by hand so that we can add flags in + * the future and not break backward compatibility. Apps will get only the + * events that they originally wanted. Be sure to add new events here! + */ +#define IN_ALL_EVENTS (IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \ + IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | \ + IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF | \ + IN_MOVE_SELF) + +#if 0 +#if defined (__alpha__) +# define __NR_inotify_init 444 +# define __NR_inotify_add_watch 445 +# define __NR_inotify_rm_watch 446 + +#elif defined (__arm__) +# define __NR_inotify_init (__NR_SYSCALL_BASE+316) +# define __NR_inotify_add_watch (__NR_SYSCALL_BASE+317) +# define __NR_inotify_rm_watch (__NR_SYSCALL_BASE+318) + +#elif defined (__frv__) +# define __NR_inotify_init 291 +# define __NR_inotify_add_watch 292 +# define __NR_inotify_rm_watch 293 + +#elif defined(__i386__) +# define __NR_inotify_init 291 +# define __NR_inotify_add_watch 292 +# define __NR_inotify_rm_watch 293 + +#elif defined (__ia64__) +# define __NR_inotify_init 1277 +# define __NR_inotify_add_watch 1278 +# define __NR_inotify_rm_watch 1279 + +#elif defined (__mips__) +# if _MIPS_SIM == _MIPS_SIM_ABI32 +# define __NR_inotify_init (__NR_Linux + 284) +# define __NR_inotify_add_watch (__NR_Linux + 285) +# define __NR_inotify_rm_watch (__NR_Linux + 286) +# endif +# if _MIPS_SIM == _MIPS_SIM_ABI64 +# define __NR_inotify_init (__NR_Linux + 243) +# define __NR_inotify_add_watch (__NR_Linux + 243) +# define __NR_inotify_rm_watch (__NR_Linux + 243) +# endif +# if _MIPS_SIM == _MIPS_SIM_NABI32 +# define __NR_inotify_init (__NR_Linux + 247) +# define __NR_inotify_add_watch (__NR_Linux + 248) +# define __NR_inotify_rm_watch (__NR_Linux + 249) +# endif + +#elif defined(__parisc__) +# define __NR_inotify_init (__NR_Linux + 269) +# define __NR_inotify_add_watch (__NR_Linux + 270) +# define __NR_inotify_rm_watch (__NR_Linux + 271) + +#elif defined(__powerpc__) || defined(__powerpc64__) +# define __NR_inotify_init 275 +# define __NR_inotify_add_watch 276 +# define __NR_inotify_rm_watch 277 + +#elif defined (__s390__) +# define __NR_inotify_init 284 +# define __NR_inotify_add_watch 285 +# define __NR_inotify_rm_watch 286 + +#elif defined (__sh__) +# define __NR_inotify_init 290 +# define __NR_inotify_add_watch 291 +# define __NR_inotify_rm_watch 292 + +#elif defined (__sh64__) +# define __NR_inotify_init 318 +# define __NR_inotify_add_watch 319 +# define __NR_inotify_rm_watch 320 + +#elif defined (__sparc__) || defined (__sparc64__) +# define __NR_inotify_init 151 +# define __NR_inotify_add_watch 152 +# define __NR_inotify_rm_watch 156 + +#elif defined(__x86_64__) +# define __NR_inotify_init 253 +# define __NR_inotify_add_watch 254 +# define __NR_inotify_rm_watch 255 + +#else +# error "Unsupported architecture!" +#endif +#endif + +#ifndef __NR_inotify_init +# error "Unsupported architecture!" +#endif +#ifndef __NR_inotify_add_watch +# error "Unsupported architecture!" +#endif +#ifndef __NR_inotify_rm_watch +# error "Unsupported architecture!" +#endif + + +static inline int inotify_init (void) +{ + return syscall (__NR_inotify_init); +} + +static inline int inotify_add_watch (int fd, const char *name, uint32_t mask) +{ + return syscall (__NR_inotify_add_watch, fd, name, mask); +} + +static inline int inotify_rm_watch (int fd, uint32_t wd) +{ + return syscall (__NR_inotify_rm_watch, fd, wd); +} + + +#endif /* _LINUX_INOTIFY_H */ diff --git a/avahi-daemon/main.c b/avahi-daemon/main.c index d0a3c85..0367b98 100644 --- a/avahi-daemon/main.c +++ b/avahi-daemon/main.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -41,6 +42,12 @@ #include #include +#ifdef HAVE_SYS_INOTIFY_H +#include +#else +#include "inotify-nosys.h" +#endif + #include #include #include @@ -654,6 +661,81 @@ static void dump(const char *text, AVAHI_GCC_UNUSED void* userdata) { avahi_log_info("%s", text); } +#ifdef HAVE_INOTIFY + +static int inotify_fd = -1; + +static void add_inotify_watches(void) { + int c = 0; + /* We ignore the return values, because one or more of these files + * might not exist and we're OK with that. In addition we never + * want to remove these watches, hence we keep their ids? */ + +#ifdef ENABLE_CHROOT + c = config.use_chroot; +#endif + + inotify_add_watch(inotify_fd, c ? "/services" : AVAHI_SERVICE_DIR, IN_CLOSE_WRITE|IN_DELETE|IN_DELETE_SELF|IN_MOVED_FROM|IN_MOVED_TO|IN_MOVE_SELF|IN_ONLYDIR); + inotify_add_watch(inotify_fd, c ? "/" : AVAHI_CONFIG_DIR, IN_CLOSE_WRITE|IN_DELETE|IN_DELETE_SELF|IN_MOVED_FROM|IN_MOVED_TO|IN_MOVE_SELF|IN_ONLYDIR); +} + +#endif + +static void reload_config(void) { + +#ifdef HAVE_INOTIFY + /* Refresh in case the config dirs have been removed */ + add_inotify_watches(); +#endif + +#ifdef ENABLE_CHROOT + static_service_load(config.use_chroot); + static_hosts_load(config.use_chroot); +#else + static_service_load(0); + static_hosts_load(0); +#endif + static_service_add_to_server(); + static_hosts_add_to_server(); + + if (resolv_conf_entry_group) + avahi_s_entry_group_reset(resolv_conf_entry_group); + + load_resolv_conf(); + + update_wide_area_servers(); + + if (config.publish_resolv_conf && resolv_conf && resolv_conf[0]) + resolv_conf_entry_group = add_dns_servers(avahi_server, resolv_conf_entry_group, resolv_conf); +} + +#ifdef HAVE_INOTIFY + +static void inotify_callback(AvahiWatch *watch, int fd, AVAHI_GCC_UNUSED AvahiWatchEvent event, AVAHI_GCC_UNUSED void *userdata) { + char* buffer; + int n = 0; + + assert(fd == inotify_fd); + assert(watch); + + ioctl(inotify_fd, FIONREAD, &n); + if (n <= 0) + n = 128; + + buffer = avahi_malloc(n); + if (read(inotify_fd, buffer, n) < 0 ) { + avahi_free(buffer); + avahi_log_error("Failed to read inotify event: %s", avahi_strerror(errno)); + return; + } + avahi_free(buffer); + + avahi_log_info("Files changed, reloading."); + reload_config(); +} + +#endif + static void signal_callback(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AVAHI_GCC_UNUSED AvahiWatchEvent event, AVAHI_GCC_UNUSED void *userdata) { int sig; const AvahiPoll *poll_api; @@ -682,26 +764,8 @@ static void signal_callback(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AVAHI_GC case SIGHUP: avahi_log_info("Got SIGHUP, reloading."); -#ifdef ENABLE_CHROOT - static_service_load(config.use_chroot); - static_hosts_load(config.use_chroot); -#else - static_service_load(0); - static_hosts_load(0); -#endif - static_service_add_to_server(); - static_hosts_add_to_server(); - - if (resolv_conf_entry_group) - avahi_s_entry_group_reset(resolv_conf_entry_group); - - load_resolv_conf(); - - update_wide_area_servers(); - - if (config.publish_resolv_conf && resolv_conf && resolv_conf[0]) - resolv_conf_entry_group = add_dns_servers(avahi_server, resolv_conf_entry_group, resolv_conf); + reload_config(); break; case SIGUSR1: @@ -724,6 +788,9 @@ static int run_server(DaemonConfig *c) { const AvahiPoll *poll_api = NULL; AvahiWatch *sig_watch = NULL; int retval_is_sent = 0; +#ifdef HAVE_INOTIFY + AvahiWatch *inotify_watch = NULL; +#endif assert(c); @@ -786,6 +853,19 @@ static int run_server(DaemonConfig *c) { #endif +#ifdef HAVE_INOTIFY + if ((inotify_fd = inotify_init()) < 0) + avahi_log_warn( "Failed to initialize inotify: %s", strerror(errno)); + else { + add_inotify_watches(); + + if (!(inotify_watch = poll_api->watch_new(poll_api, inotify_fd, AVAHI_WATCH_IN, inotify_callback, NULL))) { + avahi_log_error( "Failed to create inotify watcher"); + goto finish; + } + } +#endif + load_resolv_conf(); #ifdef ENABLE_CHROOT static_service_load(config.use_chroot); @@ -849,6 +929,13 @@ finish: if (sig_watch) poll_api->watch_free(sig_watch); +#ifdef HAVE_INOTIFY + if (inotify_watch) + poll_api->watch_free(inotify_watch); + if (inotify_fd >= 0) + close(inotify_fd); +#endif + if (simple_poll_api) { avahi_simple_poll_free(simple_poll_api); simple_poll_api = NULL; diff --git a/configure.ac b/configure.ac index 660f138..9ca1f89 100644 --- a/configure.ac +++ b/configure.ac @@ -296,6 +296,16 @@ if test "x$HAVE_DLOPEN" = "xyes" ; then fi AM_CONDITIONAL(HAVE_DLOPEN, test "x$HAVE_DLOPEN" = "xyes") +have_inotify=no +AC_CHECK_HEADERS([linux/inotify.h], [have_inotify=yes]) +AC_CHECK_HEADERS([sys/inotify.h], [have_inotify=yes]) + +AM_CONDITIONAL(HAVE_INOTIFY, test "x$have_inotify" = "xyes") + +if test "x$have_inotify" = "xyes" ; then + AC_DEFINE([HAVE_INOTIFY], 1, [Enable Linux inotify() usage]) +fi + # Check for pkg-config manually first, as if its not installed the # PKG_PROG_PKG_CONFIG macro won't be defined. AC_CHECK_PROG(have_pkg_config, pkg-config, yes, no) @@ -948,6 +958,7 @@ echo " User for avahi-autoipd: ${AVAHI_AUTOIPD_USER} Group for avahi-autoipd: ${AVAHI_AUTOIPD_GROUP} Enable chroot(): ${enable_chroot} + Enable Linux inotify: ${have_inotify} " BUILD_DAEMON="no (You need libdaemon and expat!)"