wendy

inotify based node watcher
git clone git://git.2f30.org/wendy.git
Log | Files | Refs | README | LICENSE

commit 2619339f1fb96c93f427bf088e898e713aa36e0b
parent a8a44b4a2acf56b9871abb4ecbaab64f4ff4f079
Author: Willy Goiffon <dev@z3bra.org>
Date:   Fri, 28 Feb 2020 18:05:58 +0100

Rewrite body to use SLIST from queue.h

Full rewrite that aims to be more modular and easier to hack on.
Uses simple lists for node watching, and return events by their names
rather than cryptic integer values.

Diffstat:
Aqueue.h | 534+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Astrlcpy.h | 45+++++++++++++++++++++++++++++++++++++++++++++
Mwendy.c | 300++++++++++++++++++++++++++++---------------------------------------------------
3 files changed, 686 insertions(+), 193 deletions(-)

diff --git a/queue.h b/queue.h @@ -0,0 +1,534 @@ +/* $OpenBSD: queue.h,v 1.45 2018/07/12 14:22:54 sashan Exp $ */ +/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */ + +/* + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)queue.h 8.5 (Berkeley) 8/20/94 + */ + +#ifndef _SYS_QUEUE_H_ +#define _SYS_QUEUE_H_ + +/* + * This file defines five types of data structures: singly-linked lists, + * lists, simple queues, tail queues and XOR simple queues. + * + * + * A singly-linked list is headed by a single forward pointer. The elements + * are singly linked for minimum space and pointer manipulation overhead at + * the expense of O(n) removal for arbitrary elements. New elements can be + * added to the list after an existing element or at the head of the list. + * Elements being removed from the head of the list should use the explicit + * macro for this purpose for optimum efficiency. A singly-linked list may + * only be traversed in the forward direction. Singly-linked lists are ideal + * for applications with large datasets and few or no removals or for + * implementing a LIFO queue. + * + * A list is headed by a single forward pointer (or an array of forward + * pointers for a hash table header). The elements are doubly linked + * so that an arbitrary element can be removed without a need to + * traverse the list. New elements can be added to the list before + * or after an existing element or at the head of the list. A list + * may only be traversed in the forward direction. + * + * A simple queue is headed by a pair of pointers, one to the head of the + * list and the other to the tail of the list. The elements are singly + * linked to save space, so elements can only be removed from the + * head of the list. New elements can be added to the list before or after + * an existing element, at the head of the list, or at the end of the + * list. A simple queue may only be traversed in the forward direction. + * + * A tail queue is headed by a pair of pointers, one to the head of the + * list and the other to the tail of the list. The elements are doubly + * linked so that an arbitrary element can be removed without a need to + * traverse the list. New elements can be added to the list before or + * after an existing element, at the head of the list, or at the end of + * the list. A tail queue may be traversed in either direction. + * + * An XOR simple queue is used in the same way as a regular simple queue. + * The difference is that the head structure also includes a "cookie" that + * is XOR'd with the queue pointer (first, last or next) to generate the + * real pointer value. + * + * For details on the use of these macros, see the queue(3) manual page. + */ + +#if defined(QUEUE_MACRO_DEBUG) || (defined(_KERNEL) && defined(DIAGNOSTIC)) +#define _Q_INVALID ((void *)-1) +#define _Q_INVALIDATE(a) (a) = _Q_INVALID +#else +#define _Q_INVALIDATE(a) +#endif + +/* + * Singly-linked List definitions. + */ +#define SLIST_HEAD(name, type) \ +struct name { \ + struct type *slh_first; /* first element */ \ +} + +#define SLIST_HEAD_INITIALIZER(head) \ + { NULL } + +#define SLIST_ENTRY(type) \ +struct { \ + struct type *sle_next; /* next element */ \ +} + +/* + * Singly-linked List access methods. + */ +#define SLIST_FIRST(head) ((head)->slh_first) +#define SLIST_END(head) NULL +#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) +#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) + +#define SLIST_FOREACH(var, head, field) \ + for((var) = SLIST_FIRST(head); \ + (var) != SLIST_END(head); \ + (var) = SLIST_NEXT(var, field)) + +#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ + for ((var) = SLIST_FIRST(head); \ + (var) && ((tvar) = SLIST_NEXT(var, field), 1); \ + (var) = (tvar)) + +/* + * Singly-linked List functions. + */ +#define SLIST_INIT(head) { \ + SLIST_FIRST(head) = SLIST_END(head); \ +} + +#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ + (elm)->field.sle_next = (slistelm)->field.sle_next; \ + (slistelm)->field.sle_next = (elm); \ +} while (0) + +#define SLIST_INSERT_HEAD(head, elm, field) do { \ + (elm)->field.sle_next = (head)->slh_first; \ + (head)->slh_first = (elm); \ +} while (0) + +#define SLIST_REMOVE_AFTER(elm, field) do { \ + (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \ +} while (0) + +#define SLIST_REMOVE_HEAD(head, field) do { \ + (head)->slh_first = (head)->slh_first->field.sle_next; \ +} while (0) + +#define SLIST_REMOVE(head, elm, type, field) do { \ + if ((head)->slh_first == (elm)) { \ + SLIST_REMOVE_HEAD((head), field); \ + } else { \ + struct type *curelm = (head)->slh_first; \ + \ + while (curelm->field.sle_next != (elm)) \ + curelm = curelm->field.sle_next; \ + curelm->field.sle_next = \ + curelm->field.sle_next->field.sle_next; \ + } \ + _Q_INVALIDATE((elm)->field.sle_next); \ +} while (0) + +/* + * List definitions. + */ +#define LIST_HEAD(name, type) \ +struct name { \ + struct type *lh_first; /* first element */ \ +} + +#define LIST_HEAD_INITIALIZER(head) \ + { NULL } + +#define LIST_ENTRY(type) \ +struct { \ + struct type *le_next; /* next element */ \ + struct type **le_prev; /* address of previous next element */ \ +} + +/* + * List access methods. + */ +#define LIST_FIRST(head) ((head)->lh_first) +#define LIST_END(head) NULL +#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) +#define LIST_NEXT(elm, field) ((elm)->field.le_next) + +#define LIST_FOREACH(var, head, field) \ + for((var) = LIST_FIRST(head); \ + (var)!= LIST_END(head); \ + (var) = LIST_NEXT(var, field)) + +#define LIST_FOREACH_SAFE(var, head, field, tvar) \ + for ((var) = LIST_FIRST(head); \ + (var) && ((tvar) = LIST_NEXT(var, field), 1); \ + (var) = (tvar)) + +/* + * List functions. + */ +#define LIST_INIT(head) do { \ + LIST_FIRST(head) = LIST_END(head); \ +} while (0) + +#define LIST_INSERT_AFTER(listelm, elm, field) do { \ + if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ + (listelm)->field.le_next->field.le_prev = \ + &(elm)->field.le_next; \ + (listelm)->field.le_next = (elm); \ + (elm)->field.le_prev = &(listelm)->field.le_next; \ +} while (0) + +#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ + (elm)->field.le_prev = (listelm)->field.le_prev; \ + (elm)->field.le_next = (listelm); \ + *(listelm)->field.le_prev = (elm); \ + (listelm)->field.le_prev = &(elm)->field.le_next; \ +} while (0) + +#define LIST_INSERT_HEAD(head, elm, field) do { \ + if (((elm)->field.le_next = (head)->lh_first) != NULL) \ + (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ + (head)->lh_first = (elm); \ + (elm)->field.le_prev = &(head)->lh_first; \ +} while (0) + +#define LIST_REMOVE(elm, field) do { \ + if ((elm)->field.le_next != NULL) \ + (elm)->field.le_next->field.le_prev = \ + (elm)->field.le_prev; \ + *(elm)->field.le_prev = (elm)->field.le_next; \ + _Q_INVALIDATE((elm)->field.le_prev); \ + _Q_INVALIDATE((elm)->field.le_next); \ +} while (0) + +#define LIST_REPLACE(elm, elm2, field) do { \ + if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ + (elm2)->field.le_next->field.le_prev = \ + &(elm2)->field.le_next; \ + (elm2)->field.le_prev = (elm)->field.le_prev; \ + *(elm2)->field.le_prev = (elm2); \ + _Q_INVALIDATE((elm)->field.le_prev); \ + _Q_INVALIDATE((elm)->field.le_next); \ +} while (0) + +/* + * Simple queue definitions. + */ +#define SIMPLEQ_HEAD(name, type) \ +struct name { \ + struct type *sqh_first; /* first element */ \ + struct type **sqh_last; /* addr of last next element */ \ +} + +#define SIMPLEQ_HEAD_INITIALIZER(head) \ + { NULL, &(head).sqh_first } + +#define SIMPLEQ_ENTRY(type) \ +struct { \ + struct type *sqe_next; /* next element */ \ +} + +/* + * Simple queue access methods. + */ +#define SIMPLEQ_FIRST(head) ((head)->sqh_first) +#define SIMPLEQ_END(head) NULL +#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) +#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) + +#define SIMPLEQ_FOREACH(var, head, field) \ + for((var) = SIMPLEQ_FIRST(head); \ + (var) != SIMPLEQ_END(head); \ + (var) = SIMPLEQ_NEXT(var, field)) + +#define SIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \ + for ((var) = SIMPLEQ_FIRST(head); \ + (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1); \ + (var) = (tvar)) + +/* + * Simple queue functions. + */ +#define SIMPLEQ_INIT(head) do { \ + (head)->sqh_first = NULL; \ + (head)->sqh_last = &(head)->sqh_first; \ +} while (0) + +#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ + if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ + (head)->sqh_last = &(elm)->field.sqe_next; \ + (head)->sqh_first = (elm); \ +} while (0) + +#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ + (elm)->field.sqe_next = NULL; \ + *(head)->sqh_last = (elm); \ + (head)->sqh_last = &(elm)->field.sqe_next; \ +} while (0) + +#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ + if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ + (head)->sqh_last = &(elm)->field.sqe_next; \ + (listelm)->field.sqe_next = (elm); \ +} while (0) + +#define SIMPLEQ_REMOVE_HEAD(head, field) do { \ + if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \ + (head)->sqh_last = &(head)->sqh_first; \ +} while (0) + +#define SIMPLEQ_REMOVE_AFTER(head, elm, field) do { \ + if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \ + == NULL) \ + (head)->sqh_last = &(elm)->field.sqe_next; \ +} while (0) + +#define SIMPLEQ_CONCAT(head1, head2) do { \ + if (!SIMPLEQ_EMPTY((head2))) { \ + *(head1)->sqh_last = (head2)->sqh_first; \ + (head1)->sqh_last = (head2)->sqh_last; \ + SIMPLEQ_INIT((head2)); \ + } \ +} while (0) + +/* + * XOR Simple queue definitions. + */ +#define XSIMPLEQ_HEAD(name, type) \ +struct name { \ + struct type *sqx_first; /* first element */ \ + struct type **sqx_last; /* addr of last next element */ \ + unsigned long sqx_cookie; \ +} + +#define XSIMPLEQ_ENTRY(type) \ +struct { \ + struct type *sqx_next; /* next element */ \ +} + +/* + * XOR Simple queue access methods. + */ +#define XSIMPLEQ_XOR(head, ptr) ((__typeof(ptr))((head)->sqx_cookie ^ \ + (unsigned long)(ptr))) +#define XSIMPLEQ_FIRST(head) XSIMPLEQ_XOR(head, ((head)->sqx_first)) +#define XSIMPLEQ_END(head) NULL +#define XSIMPLEQ_EMPTY(head) (XSIMPLEQ_FIRST(head) == XSIMPLEQ_END(head)) +#define XSIMPLEQ_NEXT(head, elm, field) XSIMPLEQ_XOR(head, ((elm)->field.sqx_next)) + + +#define XSIMPLEQ_FOREACH(var, head, field) \ + for ((var) = XSIMPLEQ_FIRST(head); \ + (var) != XSIMPLEQ_END(head); \ + (var) = XSIMPLEQ_NEXT(head, var, field)) + +#define XSIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \ + for ((var) = XSIMPLEQ_FIRST(head); \ + (var) && ((tvar) = XSIMPLEQ_NEXT(head, var, field), 1); \ + (var) = (tvar)) + +/* + * XOR Simple queue functions. + */ +#define XSIMPLEQ_INIT(head) do { \ + arc4random_buf(&(head)->sqx_cookie, sizeof((head)->sqx_cookie)); \ + (head)->sqx_first = XSIMPLEQ_XOR(head, NULL); \ + (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \ +} while (0) + +#define XSIMPLEQ_INSERT_HEAD(head, elm, field) do { \ + if (((elm)->field.sqx_next = (head)->sqx_first) == \ + XSIMPLEQ_XOR(head, NULL)) \ + (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ + (head)->sqx_first = XSIMPLEQ_XOR(head, (elm)); \ +} while (0) + +#define XSIMPLEQ_INSERT_TAIL(head, elm, field) do { \ + (elm)->field.sqx_next = XSIMPLEQ_XOR(head, NULL); \ + *(XSIMPLEQ_XOR(head, (head)->sqx_last)) = XSIMPLEQ_XOR(head, (elm)); \ + (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ +} while (0) + +#define XSIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ + if (((elm)->field.sqx_next = (listelm)->field.sqx_next) == \ + XSIMPLEQ_XOR(head, NULL)) \ + (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ + (listelm)->field.sqx_next = XSIMPLEQ_XOR(head, (elm)); \ +} while (0) + +#define XSIMPLEQ_REMOVE_HEAD(head, field) do { \ + if (((head)->sqx_first = XSIMPLEQ_XOR(head, \ + (head)->sqx_first)->field.sqx_next) == XSIMPLEQ_XOR(head, NULL)) \ + (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \ +} while (0) + +#define XSIMPLEQ_REMOVE_AFTER(head, elm, field) do { \ + if (((elm)->field.sqx_next = XSIMPLEQ_XOR(head, \ + (elm)->field.sqx_next)->field.sqx_next) \ + == XSIMPLEQ_XOR(head, NULL)) \ + (head)->sqx_last = \ + XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ +} while (0) + + +/* + * Tail queue definitions. + */ +#define TAILQ_HEAD(name, type) \ +struct name { \ + struct type *tqh_first; /* first element */ \ + struct type **tqh_last; /* addr of last next element */ \ +} + +#define TAILQ_HEAD_INITIALIZER(head) \ + { NULL, &(head).tqh_first } + +#define TAILQ_ENTRY(type) \ +struct { \ + struct type *tqe_next; /* next element */ \ + struct type **tqe_prev; /* address of previous next element */ \ +} + +/* + * Tail queue access methods. + */ +#define TAILQ_FIRST(head) ((head)->tqh_first) +#define TAILQ_END(head) NULL +#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) +#define TAILQ_LAST(head, headname) \ + (*(((struct headname *)((head)->tqh_last))->tqh_last)) +/* XXX */ +#define TAILQ_PREV(elm, headname, field) \ + (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) +#define TAILQ_EMPTY(head) \ + (TAILQ_FIRST(head) == TAILQ_END(head)) + +#define TAILQ_FOREACH(var, head, field) \ + for((var) = TAILQ_FIRST(head); \ + (var) != TAILQ_END(head); \ + (var) = TAILQ_NEXT(var, field)) + +#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ + for ((var) = TAILQ_FIRST(head); \ + (var) != TAILQ_END(head) && \ + ((tvar) = TAILQ_NEXT(var, field), 1); \ + (var) = (tvar)) + + +#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ + for((var) = TAILQ_LAST(head, headname); \ + (var) != TAILQ_END(head); \ + (var) = TAILQ_PREV(var, headname, field)) + +#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ + for ((var) = TAILQ_LAST(head, headname); \ + (var) != TAILQ_END(head) && \ + ((tvar) = TAILQ_PREV(var, headname, field), 1); \ + (var) = (tvar)) + +/* + * Tail queue functions. + */ +#define TAILQ_INIT(head) do { \ + (head)->tqh_first = NULL; \ + (head)->tqh_last = &(head)->tqh_first; \ +} while (0) + +#define TAILQ_INSERT_HEAD(head, elm, field) do { \ + if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ + (head)->tqh_first->field.tqe_prev = \ + &(elm)->field.tqe_next; \ + else \ + (head)->tqh_last = &(elm)->field.tqe_next; \ + (head)->tqh_first = (elm); \ + (elm)->field.tqe_prev = &(head)->tqh_first; \ +} while (0) + +#define TAILQ_INSERT_TAIL(head, elm, field) do { \ + (elm)->field.tqe_next = NULL; \ + (elm)->field.tqe_prev = (head)->tqh_last; \ + *(head)->tqh_last = (elm); \ + (head)->tqh_last = &(elm)->field.tqe_next; \ +} while (0) + +#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ + if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ + (elm)->field.tqe_next->field.tqe_prev = \ + &(elm)->field.tqe_next; \ + else \ + (head)->tqh_last = &(elm)->field.tqe_next; \ + (listelm)->field.tqe_next = (elm); \ + (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ +} while (0) + +#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ + (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ + (elm)->field.tqe_next = (listelm); \ + *(listelm)->field.tqe_prev = (elm); \ + (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ +} while (0) + +#define TAILQ_REMOVE(head, elm, field) do { \ + if (((elm)->field.tqe_next) != NULL) \ + (elm)->field.tqe_next->field.tqe_prev = \ + (elm)->field.tqe_prev; \ + else \ + (head)->tqh_last = (elm)->field.tqe_prev; \ + *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ + _Q_INVALIDATE((elm)->field.tqe_prev); \ + _Q_INVALIDATE((elm)->field.tqe_next); \ +} while (0) + +#define TAILQ_REPLACE(head, elm, elm2, field) do { \ + if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ + (elm2)->field.tqe_next->field.tqe_prev = \ + &(elm2)->field.tqe_next; \ + else \ + (head)->tqh_last = &(elm2)->field.tqe_next; \ + (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ + *(elm2)->field.tqe_prev = (elm2); \ + _Q_INVALIDATE((elm)->field.tqe_prev); \ + _Q_INVALIDATE((elm)->field.tqe_next); \ +} while (0) + +#define TAILQ_CONCAT(head1, head2, field) do { \ + if (!TAILQ_EMPTY(head2)) { \ + *(head1)->tqh_last = (head2)->tqh_first; \ + (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ + (head1)->tqh_last = (head2)->tqh_last; \ + TAILQ_INIT((head2)); \ + } \ +} while (0) + +#endif /* !_SYS_QUEUE_H_ */ diff --git a/strlcpy.h b/strlcpy.h @@ -0,0 +1,45 @@ +/* + * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#include <sys/types.h> +#include <string.h> +/* Implementation of strlcpy() for platforms that don't already have it. */ +/* + * Copy src to string dst of size siz. At most siz-1 characters + * will be copied. Always NUL terminates (unless siz == 0). + * Returns strlen(src); if retval >= siz, truncation occurred. + */ +size_t +strlcpy(char *dst, const char *src, size_t siz) +{ + char *d = dst; + const char *s = src; + size_t n = siz; + /* Copy as many bytes as will fit */ + if (n != 0) { + while (--n != 0) { + if ((*d++ = *s++) == '\0') + break; + } + } + /* Not enough room in dst, add NUL and traverse rest of src */ + if (n == 0) { + if (siz != 0) + *d = '\0'; /* NUL-terminate dst */ + while (*s++) + ; + } + return(s - src - 1); /* count does not include NUL */ +} diff --git a/wendy.c b/wendy.c @@ -1,3 +1,4 @@ +#include <errno.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> @@ -7,260 +8,173 @@ #include <sys/wait.h> #include "arg.h" +#include "queue.h" +#include "strlcpy.h" -/* definitions, defaults, bla bla blah */ -#define EVENT_SIZE (sizeof(struct inotify_event)) +#define EVSZ (sizeof(struct inotify_event) + NAME_MAX + 1) -/* maximum number of event * queuing at the same time */ -#define BUF_LEN (512 * (EVENT_SIZE+16)) - -/* macro used to retrieve the path of the node triggering the event */ -#define EVENT_PATH(e) (e->len ? e->name : wd_path(e->wd)) - -/* environment variable names set by wendy to pass to the command */ -#define ENV_PATH "WENDY_INODE" -#define ENV_MASK "WENDY_EVENT" - -/* default value for the mask when -m is not specified */ -#define DEFAULT_MASK (IN_CLOSE_WRITE|IN_MODIFY) - -/* timeout value used by default to queue the events */ -#define DEFAULT_TIMEOUT 1 - -struct node_t { +struct watcher { int wd; char path[PATH_MAX]; - struct node_t *next; + SLIST_ENTRY(watcher) entries; }; -int verbose = 0, nb = 0; -struct node_t *head = NULL; +SLIST_HEAD(watchers, watcher) head; + +char *evname[] = { + [IN_ACCESS] = "ACCESS", + [IN_MODIFY] = "MODIFY", + [IN_ATTRIB] = "ATTRIB", + [IN_CLOSE_WRITE] = "CLOSE_WRITE", + [IN_CLOSE_NOWRITE] = "CLOSE_NOWRITE", + [IN_OPEN] = "OPEN", + [IN_MOVED_FROM] = "MOVED_FROM", + [IN_MOVED_TO] = "MOVED_TO", + [IN_CREATE] = "CREATE", + [IN_DELETE] = "DELETE", + [IN_DELETE_SELF] = "DELETE_SELF", + [IN_MOVE_SELF] = "MOVE_SELF", +}; + +int verbose = 1; void usage(char *name) { - fprintf(stderr, "usage: %s [-lq] [-m mask] [-f file] [-t timeout] " - "[cmd [args..]]\n", name); + fprintf(stderr, "usage: %s [-v] [-m mask] [-f file] [cmd [args..]]\n", name); exit(1); } void -list_events() +listwatcher(struct watchers *h) { - fprintf(stdout, "IN_ACCESS ........ %u\n" - "IN_MODIFY ........ %u\n" - "IN_ATTRIB ........ %u\n" - "IN_CLOSE_WRITE ... %u\n" - "IN_CLOSE_NOWRITE . %u\n" - "IN_OPEN .......... %u\n" - "IN_MOVED_FROM .... %u\n" - "IN_MOVED_TO ...... %u\n" - "IN_CREATE ........ %u\n" - "IN_DELETE ........ %u\n" - "IN_DELETE_SELF ... %u\n" - "IN_MOVE_SELF ..... %u\n" - "IN_ALL_EVENTS .... %u\n" - "IN_UNMOUNT ....... %u\n", - IN_ACCESS, - IN_MODIFY, - IN_ATTRIB, - IN_CLOSE_WRITE, - IN_CLOSE_NOWRITE, - IN_OPEN, - IN_MOVED_FROM, - IN_MOVED_TO, - IN_CREATE, - IN_DELETE, - IN_DELETE_SELF, - IN_MOVE_SELF, - IN_ALL_EVENTS, - IN_UNMOUNT); + struct watcher *tmp; + + fprintf(stderr, "watchlist:\n"); + SLIST_FOREACH(tmp, h, entries) + fprintf(stderr, "%s (%lu)\n", tmp->path, tmp->wd); } -char * -read_filename(int fd) -{ - int i; - char *fn = NULL, ch; - fn = malloc(PATH_MAX); - if (!fn) - return NULL; +struct watcher * +getwatcher(struct watchers *h, int wd) +{ + struct watcher *tmp; - for (i=0; read(fd, &ch, 1) > 0 && i < PATH_MAX; i++) { - if (ch == 0 || ch == '\n') { - *(fn + i + 1) = 0; - return fn; - } else { - *(fn+i) = ch; - } - } + SLIST_FOREACH(tmp, h, entries) + if (tmp->wd == wd) + return tmp; return NULL; + } -struct node_t * -add_node(int wd, const char *path) +struct watcher * +watch(int fd, char *pathname, int mask) { - struct node_t *n = NULL; + size_t len; + struct watcher *w; - n = malloc(sizeof(struct node_t)); - if (!n) + w = malloc(sizeof(*w)); + if (!w) return NULL; - n->wd = wd; - strncpy(n->path, path, PATH_MAX); - n->next = head ? head : NULL; - head = n; - - nb++; - return n; -} - -const char * -wd_path(int wd) -{ - struct node_t *n = head; - - while (n && n->wd != wd) - n = n->next; + /* store full inode path */ + realpath(pathname, w->path); + w->wd = inotify_add_watch(fd, w->path, mask); + if (w->wd < 0) { + perror(pathname); + return NULL; + } - return n ? n->path : "unknown"; + SLIST_INSERT_HEAD(&head, w, entries); + return w; } -int -watch_node(int fd, const char *path, uint32_t mask) +char * +wdpath(struct inotify_event *e) { - int wd = -1; + int event; + struct watcher *w; + static char pathname[PATH_MAX]; - if (!path) - return -1; + if (e->len) + snprintf(pathname, PATH_MAX, "%s/%s", w->path, e->name); + else + strlcpy(pathname, w->path, PATH_MAX); - /* add a watcher on the file */ - wd = inotify_add_watch(fd, path, mask); - if (wd < 0) { - perror("inotify_add_watch"); - return wd; - } + return pathname; - add_node(wd, path); - return wd; } + int main (int argc, char **argv) { - int fd, len, i = 0, timeout = 0; - uint32_t mask = DEFAULT_MASK; - char buf[BUF_LEN], strmask[8]; - char *fn = NULL, *argv0 = NULL; - char **cmd = NULL; - struct inotify_event *ev; + int fd; + uint8_t buf[EVSZ]; + uint32_t mask = IN_ALL_EVENTS; + ssize_t len, off = 0; + char *argv0 = NULL; + struct watcher *tmp, *w; + struct inotify_event *e; /* get file descriptor */ fd = inotify_init(); if (fd < 0) perror("inotify_init"); - - ARGBEGIN{ + ARGBEGIN { case 'm': mask = atoi(EARGF(usage(argv0))); break; - case 'l': - list_events(); - return 0; - break; /* NOT REACHED */ case 'v': verbose++; break; case 'f': - watch_node(fd, EARGF(usage(argv0)), mask); - break; - case 't': - timeout = atoi(EARGF(usage(argv0))); + watch(fd, EARGF(usage(argv0)), mask); break; default: usage(argv0); - }ARGEND; + } ARGEND; - if (argc > 0) - cmd = argv; + while (!SLIST_EMPTY(&head) && (off || (len=read(fd, buf, EVSZ))>0)) { - /* test given arguments */ - if (!timeout) { timeout = DEFAULT_TIMEOUT; } + /* cast buffer into the event structure */ + e = (struct inotify_event *) (buf + off); - if (!nb) { - while ((fn = read_filename(0)) != NULL) - watch_node(fd, fn, mask); + /* skip watch descriptors not in out list */ + if (!(w = getwatcher(&head, e->wd))) { + inotify_rm_watch(fd, e->wd); + goto skip; + } - free(fn); - } + if (verbose && e->mask & IN_ALL_EVENTS) { + printf("%s\t%s\n", evname[e->mask & IN_ALL_EVENTS], wdpath(e)); + fflush(stdout); + } - /* start looping */ - while (nb>0) { - /* get every event raised, and queue them */ - len = read(fd, buf, BUF_LEN); - if (!len || len < 0) - perror("read"); - - i = 0; - - /* treat all events queued */ - while (i < len) { - - /* get events one by one */ - ev = (struct inotify_event *) &buf[i]; - - /* - * IN_IGNORED is triggered when a file watched - * doesn't exists anymore. In this case we - * delete the node we were watching, and try to - * watch the file again. If that fails, then the 'nb' - * variable will be decremented, so that wendy can terminate - * when there is no more files to watch. - */ - if (ev->mask & IN_IGNORED) { - nb--; - if (watch_node(fd, EVENT_PATH(ev), mask) < 0 && verbose) - fprintf(stderr, "%s: watch removed\n", EVENT_PATH(ev)); - } else if (verbose) { - printf("%u\t%s\n", ev->mask, EVENT_PATH(ev)); - fflush(stdout); - } - - /* - * Do not do anything if no command given. Also only - * execute the command if the file concerned by the - * event is the one we're watching, or if we're not - * looking for a specific file. - * - * If you don't undersand this sentence, don't worry. - * Me neither. Just trust the if(). - */ - if (cmd) { - /* - * OMG a new event! raise an alert! - * We first add two variables to the environment - * and then run the command. - * Also, double-forking. - */ - snprintf(strmask, 8, "%d", ev->mask); - setenv(ENV_MASK, strmask, 1); - setenv(ENV_PATH, EVENT_PATH(ev), 1); - if (!fork()) - if (!fork()) execvp(cmd[0], cmd); - else exit(0); - else wait(NULL); - } - - /* jump to the next one */ - i += EVENT_SIZE + ev->len; + /* + * IN_IGNORED is triggered when a file watched + * doesn't exists anymore. In this case we first try to + * add the watcher back, and if it fails, remove the + * watcher completely. + */ + if (e->mask & IN_IGNORED) { + inotify_rm_watch(fd, e->wd); + if ((w->wd = inotify_add_watch(fd, w->path, mask)) < 0) + SLIST_REMOVE(&head, w, watcher, entries); + break; } - /* wait before queuing events */ - if (nb > 0) - sleep(timeout); + +skip: + /* shift buffer offset when there's more events to read */ + off += sizeof(*e) + e->len; + if (off >= len) + off = 0; } - return EXIT_SUCCESS; + close(fd); + + return 0; }