/* * Copyright (C) 2003-2010 The Music Player Daemon Project * http://www.musicpd.org * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "config.h" #include "inotify_source.h" #include "fifo_buffer.h" #include "fd_util.h" #include <sys/inotify.h> #include <unistd.h> #include <errno.h> #include <stdbool.h> #undef G_LOG_DOMAIN #define G_LOG_DOMAIN "inotify" struct mpd_inotify_source { int fd; GIOChannel *channel; /** * The channel's source id in the GLib main loop. */ guint id; struct fifo_buffer *buffer; mpd_inotify_callback_t callback; void *callback_ctx; }; /** * A GQuark for GError instances. */ static inline GQuark mpd_inotify_quark(void) { return g_quark_from_static_string("inotify"); } static gboolean mpd_inotify_in_event(G_GNUC_UNUSED GIOChannel *_source, G_GNUC_UNUSED GIOCondition condition, gpointer data) { struct mpd_inotify_source *source = data; void *dest; size_t length; ssize_t nbytes; const struct inotify_event *event; dest = fifo_buffer_write(source->buffer, &length); if (dest == NULL) g_error("buffer full"); nbytes = read(source->fd, dest, length); if (nbytes < 0) g_error("failed to read from inotify: %s", g_strerror(errno)); if (nbytes == 0) g_error("end of file from inotify"); fifo_buffer_append(source->buffer, nbytes); while (true) { const char *name; event = fifo_buffer_read(source->buffer, &length); if (event == NULL || length < sizeof(*event) || length < sizeof(*event) + event->len) break; if (event->len > 0 && event->name[event->len - 1] == 0) name = event->name; else name = NULL; source->callback(event->wd, event->mask, name, source->callback_ctx); fifo_buffer_consume(source->buffer, sizeof(*event) + event->len); } return true; } struct mpd_inotify_source * mpd_inotify_source_new(mpd_inotify_callback_t callback, void *callback_ctx, GError **error_r) { struct mpd_inotify_source *source = g_new(struct mpd_inotify_source, 1); source->fd = inotify_init_cloexec(); if (source->fd < 0) { g_set_error(error_r, mpd_inotify_quark(), errno, "inotify_init() has failed: %s", g_strerror(errno)); g_free(source); return NULL; } source->buffer = fifo_buffer_new(4096); source->channel = g_io_channel_unix_new(source->fd); source->id = g_io_add_watch(source->channel, G_IO_IN, mpd_inotify_in_event, source); source->callback = callback; source->callback_ctx = callback_ctx; return source; } void mpd_inotify_source_free(struct mpd_inotify_source *source) { g_source_remove(source->id); g_io_channel_unref(source->channel); fifo_buffer_free(source->buffer); close(source->fd); g_free(source); } int mpd_inotify_source_add(struct mpd_inotify_source *source, const char *path_fs, unsigned mask, GError **error_r) { int wd = inotify_add_watch(source->fd, path_fs, mask); if (wd < 0) g_set_error(error_r, mpd_inotify_quark(), errno, "inotify_add_watch() has failed: %s", g_strerror(errno)); return wd; } void mpd_inotify_source_rm(struct mpd_inotify_source *source, unsigned wd) { int ret = inotify_rm_watch(source->fd, wd); if (ret < 0 && errno != EINVAL) g_warning("inotify_rm_watch() has failed: %s", g_strerror(errno)); /* EINVAL may happen here when the file has been deleted; the kernel seems to auto-unregister deleted files */ }