| 1 | /* Copyright 2017 Max Voit |
| 2 | * |
| 3 | * This file is part of sxiv. |
| 4 | * |
| 5 | * sxiv is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published |
| 7 | * by the Free Software Foundation; either version 2 of the License, |
| 8 | * or (at your option) any later version. |
| 9 | * |
| 10 | * sxiv is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with sxiv. If not, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | |
| 19 | #include <errno.h> |
| 20 | #include <stdlib.h> |
| 21 | #include <string.h> |
| 22 | #include <unistd.h> |
| 23 | #include <sys/inotify.h> |
| 24 | #include <libgen.h> |
| 25 | |
| 26 | #include "util.h" |
| 27 | #include "autoreload.h" |
| 28 | |
| 29 | CLEANUP void arl_cleanup(arl_t *arl) |
| 30 | { |
| 31 | if (arl->fd != -1) |
| 32 | close(arl->fd); |
| 33 | } |
| 34 | |
| 35 | static void arl_setup_dir(arl_t *arl, const char *filepath) |
| 36 | { |
| 37 | char *dntmp, *dn; |
| 38 | |
| 39 | if (arl->fd == -1) |
| 40 | return; |
| 41 | |
| 42 | /* get dirname */ |
| 43 | dntmp = (char*) strdup(filepath); |
| 44 | dn = (char*) dirname(dntmp); |
| 45 | |
| 46 | /* this is not one-shot as other stuff may be created too |
| 47 | * note: we won't handle deletion of the directory itself, |
| 48 | * this is a design decision |
| 49 | */ |
| 50 | arl->wd = inotify_add_watch(arl->fd, dn, IN_CREATE); |
| 51 | if (arl->wd == -1) |
| 52 | error(0, 0, "%s: Error watching directory", dn); |
| 53 | else |
| 54 | arl->watching_dir = true; |
| 55 | |
| 56 | free(dntmp); |
| 57 | } |
| 58 | |
| 59 | union { |
| 60 | char d[4096]; /* aligned buffer */ |
| 61 | struct inotify_event e; |
| 62 | } buf; |
| 63 | |
| 64 | bool arl_handle(arl_t *arl, const char *filepath) |
| 65 | { |
| 66 | bool reload = false; |
| 67 | char *ptr; |
| 68 | const struct inotify_event *event; |
| 69 | |
| 70 | for (;;) { |
| 71 | ssize_t len = read(arl->fd, buf.d, sizeof(buf.d)); |
| 72 | |
| 73 | if (len == -1) { |
| 74 | if (errno == EINTR) |
| 75 | continue; |
| 76 | break; |
| 77 | } |
| 78 | for (ptr = buf.d; ptr < buf.d + len; ptr += sizeof(*event) + event->len) { |
| 79 | event = (const struct inotify_event*) ptr; |
| 80 | |
| 81 | /* events from watching the file itself */ |
| 82 | if (event->mask & IN_CLOSE_WRITE) { |
| 83 | reload = true; |
| 84 | } |
| 85 | if (event->mask & IN_DELETE_SELF) |
| 86 | arl_setup_dir(arl, filepath); |
| 87 | |
| 88 | /* events from watching the file's directory */ |
| 89 | if (event->mask & IN_CREATE) { |
| 90 | char *fntmp = strdup(filepath); |
| 91 | char *fn = basename(fntmp); |
| 92 | |
| 93 | if (STREQ(event->name, fn)) { |
| 94 | /* this is the file we're looking for */ |
| 95 | |
| 96 | /* cleanup, this has not been one-shot */ |
| 97 | if (arl->watching_dir) { |
| 98 | inotify_rm_watch(arl->fd, arl->wd); |
| 99 | arl->watching_dir = false; |
| 100 | } |
| 101 | reload = true; |
| 102 | } |
| 103 | free(fntmp); |
| 104 | } |
| 105 | } |
| 106 | } |
| 107 | return reload; |
| 108 | } |
| 109 | |
| 110 | void arl_init(arl_t *arl) |
| 111 | { |
| 112 | /* this needs to be done only once */ |
| 113 | arl->fd = inotify_init1(IN_CLOEXEC | IN_NONBLOCK); |
| 114 | arl->watching_dir = false; |
| 115 | if (arl->fd == -1) |
| 116 | error(0, 0, "Could not initialize inotify, no automatic image reloading"); |
| 117 | } |
| 118 | |
| 119 | void arl_setup(arl_t *arl, const char *filepath) |
| 120 | { |
| 121 | if (arl->fd == -1) |
| 122 | return; |
| 123 | |
| 124 | /* may have switched from a deleted to another image */ |
| 125 | if (arl->watching_dir) { |
| 126 | inotify_rm_watch(arl->fd, arl->wd); |
| 127 | arl->watching_dir = false; |
| 128 | } |
| 129 | |
| 130 | arl->wd = inotify_add_watch(arl->fd, filepath, |
| 131 | IN_ONESHOT | IN_CLOSE_WRITE | IN_DELETE_SELF); |
| 132 | if (arl->wd == -1) |
| 133 | error(0, 0, "%s: Error watching file", filepath); |
| 134 | } |
| 135 | |