1 /*
2  * Create a squashfs filesystem.  This is a highly compressed read only
3  * filesystem.
4  *
5  * Copyright (c) 2013, 2014
6  * Phillip Lougher <phillip@squashfs.org.uk>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2,
11  * or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21  *
22  * restore.c
23  */
24 
25 #include <pthread.h>
26 #include <sys/ioctl.h>
27 #include <unistd.h>
28 #include <signal.h>
29 #include <sys/time.h>
30 #include <stdio.h>
31 #include <math.h>
32 #include <stdarg.h>
33 #include <errno.h>
34 #include <stdlib.h>
35 #include <dirent.h>
36 #include <sys/types.h>
37 #include <sys/stat.h>
38 
39 #include "caches-queues-lists.h"
40 #include "squashfs_fs.h"
41 #include "mksquashfs.h"
42 #include "error.h"
43 #include "progressbar.h"
44 #include "info.h"
45 
46 #define FALSE 0
47 #define TRUE 1
48 
49 extern pthread_t reader_thread, writer_thread, main_thread;
50 extern pthread_t *deflator_thread, *frag_deflator_thread, *frag_thread;
51 extern struct queue *to_deflate, *to_writer, *to_frag, *to_process_frag;
52 extern struct seq_queue *to_main;
53 extern void restorefs();
54 extern int processors;
55 
56 static int interrupted = 0;
57 static pthread_t restore_thread;
58 
restore_thrd(void * arg)59 void *restore_thrd(void *arg)
60 {
61 	sigset_t sigmask, old_mask;
62 	int i, sig;
63 
64 	sigemptyset(&sigmask);
65 	sigaddset(&sigmask, SIGINT);
66 	sigaddset(&sigmask, SIGTERM);
67 	sigaddset(&sigmask, SIGUSR1);
68 	pthread_sigmask(SIG_BLOCK, &sigmask, &old_mask);
69 
70 	while(1) {
71 		sigwait(&sigmask, &sig);
72 
73 		if((sig == SIGINT || sig == SIGTERM) && !interrupted) {
74 			ERROR("Interrupting will restore original "
75 				"filesystem!\n");
76                 	ERROR("Interrupt again to quit\n");
77 			interrupted = TRUE;
78 			continue;
79 		}
80 
81 		/* kill main thread/worker threads and restore */
82 		set_progressbar_state(FALSE);
83 		disable_info();
84 
85 		/* first kill the reader thread */
86 		pthread_cancel(reader_thread);
87 		pthread_join(reader_thread, NULL);
88 
89 		/*
90 		 * then flush the reader to deflator thread(s) output queue.
91 		 * The deflator thread(s) will idle
92 		 */
93 		queue_flush(to_deflate);
94 
95 		/* now kill the deflator thread(s) */
96 		for(i = 0; i < processors; i++)
97 			pthread_cancel(deflator_thread[i]);
98 		for(i = 0; i < processors; i++)
99 			pthread_join(deflator_thread[i], NULL);
100 
101 		/*
102 		 * then flush the reader to process fragment thread(s) output
103 		 * queue.  The process fragment thread(s) will idle
104 		 */
105 		queue_flush(to_process_frag);
106 
107 		/* now kill the process fragment thread(s) */
108 		for(i = 0; i < processors; i++)
109 			pthread_cancel(frag_thread[i]);
110 		for(i = 0; i < processors; i++)
111 			pthread_join(frag_thread[i], NULL);
112 
113 		/*
114 		 * then flush the reader/deflator/process fragment to main
115 		 * thread output queue.  The main thread will idle
116 		 */
117 		seq_queue_flush(to_main);
118 
119 		/* now kill the main thread */
120 		pthread_cancel(main_thread);
121 		pthread_join(main_thread, NULL);
122 
123 		/* then flush the main thread to fragment deflator thread(s)
124 		 * queue.  The fragment deflator thread(s) will idle
125 		 */
126 		queue_flush(to_frag);
127 
128 		/* now kill the fragment deflator thread(s) */
129 		for(i = 0; i < processors; i++)
130 			pthread_cancel(frag_deflator_thread[i]);
131 		for(i = 0; i < processors; i++)
132 			pthread_join(frag_deflator_thread[i], NULL);
133 
134 		/*
135 		 * then flush the main thread/fragment deflator thread(s)
136 		 * to writer thread queue.  The writer thread will idle
137 		 */
138 		queue_flush(to_writer);
139 
140 		/* now kill the writer thread */
141 		pthread_cancel(writer_thread);
142 		pthread_join(writer_thread, NULL);
143 
144 		TRACE("All threads cancelled\n");
145 
146 		restorefs();
147 	}
148 }
149 
150 
init_restore_thread()151 pthread_t *init_restore_thread()
152 {
153 	pthread_create(&restore_thread, NULL, restore_thrd, NULL);
154 	return &restore_thread;
155 }
156