Krolyxon
Commit 278f0ce

Branches

Refs →

nsxivautoreload_inotify.c

112 lines · 2.6 KB · C

1/* Copyright 2017 Max Voit, Bert Muennich
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 "sxiv.h"
20
21#include <errno.h>
22#include <stdlib.h>
23#include <string.h>
24#include <unistd.h>
25#include <sys/inotify.h>
26
27void arl_init(arl_t *arl)
28{
29 arl->fd = inotify_init1(IN_CLOEXEC | IN_NONBLOCK);
30 arl->wd_dir = arl->wd_file = -1;
31 if (arl->fd == -1)
32 error(0, 0, "Could not initialize inotify, no automatic image reloading");
33}
34
35CLEANUP void arl_cleanup(arl_t *arl)
36{
37 if (arl->fd != -1)
38 close(arl->fd);
39 free(arl->filename);
40}
41
42static void rm_watch(int fd, int *wd)
43{
44 if (*wd != -1) {
45 inotify_rm_watch(fd, *wd);
46 *wd = -1;
47 }
48}
49
50static void add_watch(int fd, int *wd, const char *path, uint32_t mask)
51{
52 *wd = inotify_add_watch(fd, path, mask);
53 if (*wd == -1)
54 error(0, errno, "inotify: %s", path);
55}
56
57void arl_setup(arl_t *arl, const char *filepath)
58{
59 char *base = strrchr(filepath, '/');
60
61 if (arl->fd == -1)
62 return;
63
64 rm_watch(arl->fd, &arl->wd_dir);
65 rm_watch(arl->fd, &arl->wd_file);
66
67 add_watch(arl->fd, &arl->wd_file, filepath, IN_CLOSE_WRITE | IN_DELETE_SELF);
68
69 free(arl->filename);
70 arl->filename = estrdup(filepath);
71
72 if (base != NULL) {
73 arl->filename[++base - filepath] = '\0';
74 add_watch(arl->fd, &arl->wd_dir, arl->filename, IN_CREATE | IN_MOVED_TO);
75 strcpy(arl->filename, base);
76 }
77}
78
79union {
80 char d[4096]; /* aligned buffer */
81 struct inotify_event e;
82} buf;
83
84bool arl_handle(arl_t *arl)
85{
86 bool reload = false;
87 char *ptr;
88 const struct inotify_event *e;
89
90 for (;;) {
91 ssize_t len = read(arl->fd, buf.d, sizeof(buf.d));
92
93 if (len == -1) {
94 if (errno == EINTR)
95 continue;
96 break;
97 }
98 for (ptr = buf.d; ptr < buf.d + len; ptr += sizeof(*e) + e->len) {
99 e = (const struct inotify_event*) ptr;
100 if (e->wd == arl->wd_file && (e->mask & IN_CLOSE_WRITE)) {
101 reload = true;
102 } else if (e->wd == arl->wd_file && (e->mask & IN_DELETE_SELF)) {
103 rm_watch(arl->fd, &arl->wd_file);
104 } else if (e->wd == arl->wd_dir && (e->mask & (IN_CREATE | IN_MOVED_TO))) {
105 if (STREQ(e->name, arl->filename))
106 reload = true;
107 }
108 }
109 }
110 return reload;
111}
112