Ticket #95: avahi-daemon-inotify.diff

(a) /dev/null vs. (b) avahi-0.6.16/avahi-daemon/inotify/inotify-nosys.h

@@ +1 @@
+/*
+ * This header is used if <sys/inotify.h> cannot be found.
+ *
+ * Inode based directory notification for Linux
+ *
+ * Copyright (C) 2005 John McCutchan
+ */
+
+#ifndef _LINUX_INOTIFY_H
+#define _LINUX_INOTIFY_H
+
+#include <stdint.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <asm/unistd.h>
+
+/*
+ * 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 */

(a) /dev/null vs. (b) avahi-0.6.16/avahi-daemon/inotify/inotify.h

@@ +1 @@
+#ifndef _INOTIFYTOOLS_INOTIFY_H
+#define _INOTIFYTOOLS_INOTIFY_H 1
+
+/* this is defined to 1 if <sys/inotify.h> works. */
+#undef SYS_INOTIFY_H_EXISTS_AND_WORKS
+
+
+#ifdef SYS_INOTIFY_H_EXISTS_AND_WORKS
+#include <sys/inotify.h>
+#else
+#include "inotify-nosys.h"
+#endif // SYS_INOTIFY_H_EXISTS_AND_WORKS
+
+
+#endif
+

avahi-daemon/main.c

@@ -40 +40 @@
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/socket.h>
+#include <inotify/inotify.h>
 
 #include <libdaemon/dfork.h>
 #include <libdaemon/dsignal.h>
@@ -713 +714 @@
     }
 }
 
+static void inotify_callback(AvahiWatch *watch, AVAHI_GCC_UNUSED int fd, AVAHI_GCC_UNUSED AvahiWatchEvent event, AVAHI_GCC_UNUSED void *userdata) {
+    char buffer[128];
+    int inotify_fd = (int) userdata;
+
+    assert(watch);
+
+    //read(fd, &buffer, sizeof(buffer)) != sizeof(buffer);
+    if( read(inotify_fd, &buffer[0], sizeof(buffer)) < 0 ) {
+        avahi_log_error("Failed to read inotify event.");
+    return;
+    }
+
+    avahi_log_info("Files changed, 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);
+}
+
 /* Imported from ../avahi-client/nss-check.c */
 int avahi_nss_support(void);
 
@@ -722 +757 @@
     const AvahiPoll *poll_api = NULL;
     AvahiWatch *sig_watch = NULL;
     int retval_is_sent = 0;
+    int inotify_fd = 0;
+    int inotify_wd = 0;
+    AvahiWatch *inotify_watch = NULL;
 
     assert(c);
 
@@ -745 +783 @@
         goto finish;
     }
 
+    /* iNotify */
+    if( (inotify_fd = inotify_init()) < 0 ) {
+        avahi_log_error( "Failed to initialize inotify");
+        goto finish;
+    }
+    if( (inotify_wd = inotify_add_watch(inotify_fd, "/etc/avahi/services",
+            IN_CLOSE_WRITE|IN_CREATE|IN_DELETE|IN_MODIFY|IN_MOVED_FROM|IN_MOVED_TO)) < 0 ) {
+        avahi_log_error( "Failed to initialize add inotify watch");
+        goto finish;
+    }
+    if (!(inotify_watch = poll_api->watch_new(poll_api, inotify_fd, AVAHI_WATCH_IN, inotify_callback, inotify_fd))) {
+        avahi_log_error( "Failed to create signal watcher");
+        goto finish;
+    }
+
     if (simple_protocol_setup(poll_api) < 0)
         goto finish;
 
@@ -847 +900 @@
     if (sig_watch)
         poll_api->watch_free(sig_watch);
 
+    if (inotify_wd)
+        inotify_rm_watch(inotify_fd, inotify_wd);
+    if (inotify_watch)
+        poll_api->watch_free(inotify_watch);
+
     if (simple_poll_api) {
         avahi_simple_poll_free(simple_poll_api);
         simple_poll_api = NULL;