inotifyd: exit if x event happened for all files

 fix FIONREAD parameter type
 fix default mask code
 shrink help text

function                                             old     new   delta
inotifyd_main                                        497     506      +9
packed_usage                                       25446   25431     -15
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 9/-15)              Total: -6 bytes

diff --git a/include/usage.h b/include/usage.h
index 9c0c9d761236e6dd35e24576d13919d7e61e1f3e..5223e9e18bc9f9ec25c28828ad693c5a48aa8a39 100644 (file)
--- a/include/usage.h
+++ b/include/usage.h
@@ -1838,16 +1838,11 @@
 "      ::shutdown:/sbin/swapoff -a\n"
 
 #define inotifyd_trivial_usage \
-       "/user/space/agent dir/or/file/being/watched[:mask] ..."
+       "PROG FILE1[:MASK] ..."
 #define inotifyd_full_usage "\n\n" \
-       "Run userspace agent on filesystem changes." \
-     "\nWhen a filesystem event matching the mask occurs" \
-     "\non specified file /user/space/agent is run" \
-     "\nwith the parameters:" \
-     "\n1. actual event(s)" \
-     "\n2. file name" \
-     "\n3. name of subfile (if any)" \
-     "\ninotifyd waits for agent to exit." \
+       "Run PROG on filesystem changes." \
+     "\nWhen a filesystem event matching MASK occurs on FILEn," \
+     "\nPROG <actual_event(s)> <FILEn> [<subfile_name>] is run." \
      "\nEvents:" \
      "\n       a       File is accessed" \
      "\n       c       File is modified" \
@@ -1865,6 +1860,9 @@
      "\n       y       Subfile is moved out of dir" \
      "\n       n       Subfile is created" \
      "\n       d       Subfile is deleted" \
+     "\n" \
+     "\ninotifyd waits for PROG to exit." \
+     "\nWhen x event happens for all FILEs, inotifyd exits" \
 
 #define insmod_trivial_usage \
        USE_FEATURE_2_4_MODULES("[OPTION]... ") "MODULE [symbol=value]..."

diff --git a/miscutils/inotifyd.c b/miscutils/inotifyd.c
index 656510453a3269ac84936c7112f9f9d6e60d49c1..fdf2a2c2be678c31bdbc53364af21e87d07d9ffd 100644 (file)
--- a/miscutils/inotifyd.c
+++ b/miscutils/inotifyd.c
@@ -44,6 +44,7 @@ static const char mask_names[] ALIGN1 =
        "D"     // 0x00000400   Self was deleted
        "M"     // 0x00000800   Self was moved
        "\0"    // 0x00001000   (unused)
+       // Kernel events, always reported:
        "u"     // 0x00002000   Backing fs was unmounted
        "o"     // 0x00004000   Event queued overflowed
        "x"     // 0x00008000   File is no longer watched (usually deleted)
@@ -56,27 +57,38 @@ extern int inotify_init(void);
 extern int inotify_add_watch(int fd, const char *path, uint32_t mask);
 
 int inotifyd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int inotifyd_main(int argc UNUSED_PARAM, char **argv)
+int inotifyd_main(int argc, char **argv)
 {
        int n;
-       unsigned mask = IN_ALL_EVENTS; // assume we want all events
+       unsigned mask;
        struct pollfd pfd;
-       char **watched = ++argv; // watched name list
-       const char *args[] = { *argv, NULL, NULL, NULL, NULL };
+       char **watches; // names of files being watched
+       const char *args[5];
 
        // sanity check: agent and at least one watch must be given
-       if (!argv[0] || !argv[1])
+       if (!argv[1] || !argv[2])
                bb_show_usage();
 
+       argv++;
+       // inotify_add_watch will number watched files
+       // starting from 1, thus watches[0] is unimportant,
+       // and 1st file name is watches[1].
+       watches = argv;
+       args[0] = *argv;
+       args[4] = NULL;
+       argc -= 2; // number of files we watch
+
        // open inotify
        pfd.fd = inotify_init();
        if (pfd.fd < 0)
                bb_perror_msg_and_die("no kernel support");
 
-       // setup watched
+       // setup watches
        while (*++argv) {
                char *path = *argv;
                char *masks = strchr(path, ':');
+
+               mask = 0x0fff; // assuming we want all non-kernel events
                // if mask is specified ->
                if (masks) {
                        *masks = '\0'; // split path and mask
@@ -102,10 +114,9 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv)
        // do watch
        pfd.events = POLLIN;
        while (1) {
-               ssize_t len;
+               int len;
                void *buf;
                struct inotify_event *ie;
-
  again:
                if (bb_got_signal)
                        break;
@@ -124,6 +135,7 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv)
                        break;
 
                // read out all pending events
+               // (NB: len must be int, not ssize_t or long!)
                xioctl(pfd.fd, FIONREAD, &len);
 #define eventbuf bb_common_bufsiz1
                ie = buf = (len <= sizeof(eventbuf)) ? eventbuf : xmalloc(len);
@@ -142,11 +154,15 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv)
                                }
                                *s = '\0';
 //                             bb_error_msg("exec %s %08X\t%s\t%s\t%s", args[0],
-//                                     ie->mask, events, watched[ie->wd], ie->len ? ie->name : "");
+//                                     ie->mask, events, watches[ie->wd], ie->len ? ie->name : "");
                                args[1] = events;
-                               args[2] = watched[ie->wd];
+                               args[2] = watches[ie->wd];
                                args[3] = ie->len ? ie->name : NULL;
                                wait4pid(xspawn((char **)args));
+                               // we are done if all files got final x event
+                               if (ie->mask & 0x8000)
+                                       if (--argc <= 0)
+                                               goto done;
                        }
                        // next event
                        i = sizeof(struct inotify_event) + ie->len;
@@ -155,7 +171,7 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv)
                }
                if (eventbuf != buf)
                        free(buf);
-       }
-
-       return EXIT_SUCCESS;
+       } // while (1)
+ done:
+       return bb_got_signal;
 }