X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=miscutils%2Finotifyd.c;h=7a1a6a2e533442bb77e5e642206169a86c62d6a3;hb=45dc96c8a6dce3aeea983f6c32572d4cee646b5d;hp=216a696543e105f3685a456a49b6bd571a4d6b7c;hpb=289ff0e3411543446f40cfa45db606431a4657e1;p=oweals%2Fbusybox.git diff --git a/miscutils/inotifyd.c b/miscutils/inotifyd.c index 216a69654..7a1a6a2e5 100644 --- a/miscutils/inotifyd.c +++ b/miscutils/inotifyd.c @@ -5,7 +5,7 @@ * * Copyright (C) 2008 by Vladimir Dronnikov * - * Licensed under GPLv2, see file LICENSE in this tarball for details. + * Licensed under GPLv2, see file LICENSE in this source tree. */ /* @@ -27,6 +27,34 @@ * See below for mask names explanation. */ +//usage:#define inotifyd_trivial_usage +//usage: "PROG FILE1[:MASK]..." +//usage:#define inotifyd_full_usage "\n\n" +//usage: "Run PROG on filesystem changes." +//usage: "\nWhen a filesystem event matching MASK occurs on FILEn," +//usage: "\nPROG ACTUAL_EVENTS FILEn [SUBFILE] is run." +//usage: "\nIf PROG is -, events are sent to stdout." +//usage: "\nEvents:" +//usage: "\n a File is accessed" +//usage: "\n c File is modified" +//usage: "\n e Metadata changed" +//usage: "\n w Writable file is closed" +//usage: "\n 0 Unwritable file is closed" +//usage: "\n r File is opened" +//usage: "\n D File is deleted" +//usage: "\n M File is moved" +//usage: "\n u Backing fs is unmounted" +//usage: "\n o Event queue overflowed" +//usage: "\n x File can't be watched anymore" +//usage: "\nIf watching a directory:" +//usage: "\n m Subfile is moved into dir" +//usage: "\n y Subfile is moved out of dir" +//usage: "\n n Subfile is created" +//usage: "\n d Subfile is deleted" +//usage: "\n" +//usage: "\ninotifyd waits for PROG to exit." +//usage: "\nWhen x event happens for all FILEs, inotifyd exits." + #include "libbb.h" #include @@ -34,8 +62,8 @@ static const char mask_names[] ALIGN1 = "a" // 0x00000001 File was accessed "c" // 0x00000002 File was modified "e" // 0x00000004 Metadata changed - "w" // 0x00000008 Writtable file was closed - "0" // 0x00000010 Unwrittable file closed + "w" // 0x00000008 Writable file was closed + "0" // 0x00000010 Unwritable file closed "r" // 0x00000020 File was opened "m" // 0x00000040 File was moved from X "y" // 0x00000080 File was moved to Y @@ -43,43 +71,59 @@ static const char mask_names[] ALIGN1 = "d" // 0x00000200 Subfile was deleted "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) ; - -extern int inotify_init(void); -extern int inotify_add_watch(int fd, const char *path, uint32_t mask); +enum { + MASK_BITS = sizeof(mask_names) - 1 +}; 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[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 // convert mask names to mask bitset mask = 0; while (*++masks) { - int i = strchr(mask_names, *masks) - mask_names; - if (i >= 0) { - mask |= (1 << i); - } + const char *found; + found = memchr(mask_names, *masks, MASK_BITS); + if (found) + mask |= (1 << (found - mask_names)); } } // add watch @@ -95,10 +139,9 @@ 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; @@ -117,6 +160,7 @@ 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); @@ -124,21 +168,37 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv) // process events. N.B. events may vary in length while (len > 0) { int i; - char events[sizeof(mask_names)]; - char *s = events; - unsigned m = ie->mask; - - for (i = 0; i < sizeof(mask_names)-1; ++i, m >>= 1) { - if (m & 1) - *s++ = mask_names[i]; + // cache relevant events mask + unsigned m = ie->mask & ((1 << MASK_BITS) - 1); + if (m) { + char events[MASK_BITS + 1]; + char *s = events; + for (i = 0; i < MASK_BITS; ++i, m >>= 1) { + if ((m & 1) && (mask_names[i] != '\0')) + *s++ = mask_names[i]; + } + *s = '\0'; + if (LONE_CHAR(args[0], '-')) { + /* "inotifyd - FILE": built-in echo */ + printf(ie->len ? "%s\t%s\t%s\n" : "%s\t%s\n", events, + watches[ie->wd], + ie->name); + fflush(stdout); + } else { +// bb_error_msg("exec %s %08X\t%s\t%s\t%s", args[0], +// ie->mask, events, watches[ie->wd], ie->len ? ie->name : ""); + args[1] = events; + args[2] = watches[ie->wd]; + args[3] = ie->len ? ie->name : NULL; + spawn_and_wait((char **)args); + } + // we are done if all files got final x event + if (ie->mask & 0x8000) { + if (--argc <= 0) + goto done; + inotify_rm_watch(pfd.fd, ie->wd); + } } - *s = '\0'; - //bb_error_msg("exec %s %08X\t%s\t%s\t%s", agent, - // ie->mask, events, watched[ie->wd], ie->len ? ie->name : ""); - args[1] = events; - args[2] = watched[ie->wd]; - args[3] = ie->len ? ie->name : NULL; - wait4pid(xspawn((char **)args)); // next event i = sizeof(struct inotify_event) + ie->len; len -= i; @@ -146,7 +206,7 @@ int inotifyd_main(int argc UNUSED_PARAM, char **argv) } if (eventbuf != buf) free(buf); - } - - return EXIT_SUCCESS; + } // while (1) + done: + return bb_got_signal; }