1 // Copyright (C) 2011 The Android Open Source Project
2 //
3 // This software is licensed under the terms of the GNU General Public
4 // License version 2, as published by the Free Software Foundation, and
5 // may be copied, distributed, and modified under those terms.
6 //
7 // This program is distributed in the hope that it will be useful,
8 // but WITHOUT ANY WARRANTY; without even the implied warranty of
9 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 // GNU General Public License for more details.
11
12 #include "android/log-rotate.h"
13 #include "net/net.h"
14 #include "slirp-android/libslirp.h"
15 #include "sysemu/sysemu.h"
16
17 #include <stdio.h>
18
19 #ifdef _WIN32
20
qemu_log_rotation_init(void)21 void qemu_log_rotation_init(void) {
22 // Nothing to do on Win32 for now.
23 }
24
qemu_log_rotation_poll(void)25 void qemu_log_rotation_poll(void) {
26 // Nothing to do on Win32 for now.
27 }
28
29 #else // !_WIN32
30
31 #include <sys/signal.h>
32
33 static int rotate_logs_requested = 0;
34
rotate_qemu_logs_handler(int signum)35 static void rotate_qemu_logs_handler(int signum) {
36 rotate_logs_requested = 1;
37 }
38
qemu_log_rotation_init(void)39 void qemu_log_rotation_init(void) {
40 // Install SIGUSR1 signal handler.
41 struct sigaction act;
42 sigfillset(&act.sa_mask);
43 act.sa_flags = 0;
44 act.sa_handler = rotate_qemu_logs_handler;
45 if (sigaction(SIGUSR1, &act, NULL) == -1) {
46 fprintf(stderr, "Failed to setup SIGUSR1 handler to clear Qemu logs\n");
47 exit(-1);
48 }
49 }
50
51
52 // Clears the passed qemu log when the rotate_logs_requested
53 // is set. We need to clear the logs between the tasks that do not
54 // require restarting Qemu.
rotate_log(FILE * old_log_fd,const char * filename)55 static FILE* rotate_log(FILE* old_log_fd, const char* filename) {
56 FILE* new_log_fd = NULL;
57 if (old_log_fd) {
58 if (fclose(old_log_fd) == -1) {
59 fprintf(stderr, "Cannot close old_log fd\n");
60 exit(errno);
61 }
62 }
63
64 if (!filename) {
65 fprintf(stderr, "The log filename to be rotated is not provided");
66 exit(-1);
67 }
68
69 new_log_fd = fopen(filename , "wb+");
70 if (new_log_fd == NULL) {
71 fprintf(stderr, "Cannot open the log file: %s for write.\n",
72 filename);
73 exit(1);
74 }
75
76 return new_log_fd;
77 }
78
79
qemu_log_rotation_poll(void)80 void qemu_log_rotation_poll(void) {
81 if (!rotate_logs_requested)
82 return;
83
84 FILE* new_dns_log_fd = rotate_log(get_slirp_dns_log_fd(),
85 dns_log_filename);
86 FILE* new_drop_log_fd = rotate_log(get_slirp_drop_log_fd(),
87 drop_log_filename);
88 slirp_dns_log_fd(new_dns_log_fd);
89 slirp_drop_log_fd(new_drop_log_fd);
90 rotate_logs_requested = 0;
91 }
92
93 #endif // !_WIN32
94