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Based on kernel version 3.13. Page generated on 2014-01-20 22:03 EST.

1	/*
2	 * dslm.c
3	 * Simple Disk Sleep Monitor
4	 *  by Bartek Kania
5	 * Licensed under the GPL
6	 */
7	#include <unistd.h>
8	#include <stdlib.h>
9	#include <stdio.h>
10	#include <fcntl.h>
11	#include <errno.h>
12	#include <time.h>
13	#include <string.h>
14	#include <signal.h>
15	#include <sys/ioctl.h>
16	#include <linux/hdreg.h>
17	
18	#ifdef DEBUG
19	#define D(x) x
20	#else
21	#define D(x)
22	#endif
23	
24	int endit = 0;
25	
26	/* Check if the disk is in powersave-mode
27	 * Most of the code is stolen from hdparm.
28	 * 1 = active, 0 = standby/sleep, -1 = unknown */
29	static int check_powermode(int fd)
30	{
31	    unsigned char args[4] = {WIN_CHECKPOWERMODE1,0,0,0};
32	    int state;
33	
34	    if (ioctl(fd, HDIO_DRIVE_CMD, &args)
35		&& (args[0] = WIN_CHECKPOWERMODE2) /* try again with 0x98 */
36		&& ioctl(fd, HDIO_DRIVE_CMD, &args)) {
37		if (errno != EIO || args[0] != 0 || args[1] != 0) {
38		    state = -1; /* "unknown"; */
39		} else
40		    state = 0; /* "sleeping"; */
41	    } else {
42		state = (args[2] == 255) ? 1 : 0;
43	    }
44	    D(printf(" drive state is:  %d\n", state));
45	
46	    return state;
47	}
48	
49	static char *state_name(int i)
50	{
51	    if (i == -1) return "unknown";
52	    if (i == 0) return "sleeping";
53	    if (i == 1) return "active";
54	
55	    return "internal error";
56	}
57	
58	static char *myctime(time_t time)
59	{
60	    char *ts = ctime(&time);
61	    ts[strlen(ts) - 1] = 0;
62	
63	    return ts;
64	}
65	
66	static void measure(int fd)
67	{
68	    time_t start_time;
69	    int last_state;
70	    time_t last_time;
71	    int curr_state;
72	    time_t curr_time = 0;
73	    time_t time_diff;
74	    time_t active_time = 0;
75	    time_t sleep_time = 0;
76	    time_t unknown_time = 0;
77	    time_t total_time = 0;
78	    int changes = 0;
79	    float tmp;
80	
81	    printf("Starting measurements\n");
82	
83	    last_state = check_powermode(fd);
84	    start_time = last_time = time(0);
85	    printf("  System is in state %s\n\n", state_name(last_state));
86	
87	    while(!endit) {
88		sleep(1);
89		curr_state = check_powermode(fd);
90	
91		if (curr_state != last_state || endit) {
92		    changes++;
93		    curr_time = time(0);
94		    time_diff = curr_time - last_time;
95	
96		    if (last_state == 1) active_time += time_diff;
97		    else if (last_state == 0) sleep_time += time_diff;
98		    else unknown_time += time_diff;
99	
100		    last_state = curr_state;
101		    last_time = curr_time;
102	
103		    printf("%s: State-change to %s\n", myctime(curr_time),
104			   state_name(curr_state));
105		}
106	    }
107	    changes--; /* Compensate for SIGINT */
108	
109	    total_time = time(0) - start_time;
110	    printf("\nTotal running time:  %lus\n", curr_time - start_time);
111	    printf(" State changed %d times\n", changes);
112	
113	    tmp = (float)sleep_time / (float)total_time * 100;
114	    printf(" Time in sleep state:   %lus (%.2f%%)\n", sleep_time, tmp);
115	    tmp = (float)active_time / (float)total_time * 100;
116	    printf(" Time in active state:  %lus (%.2f%%)\n", active_time, tmp);
117	    tmp = (float)unknown_time / (float)total_time * 100;
118	    printf(" Time in unknown state: %lus (%.2f%%)\n", unknown_time, tmp);
119	}
120	
121	static void ender(int s)
122	{
123	    endit = 1;
124	}
125	
126	static void usage(void)
127	{
128	    puts("usage: dslm [-w <time>] <disk>");
129	    exit(0);
130	}
131	
132	int main(int argc, char **argv)
133	{
134	    int fd;
135	    char *disk = 0;
136	    int settle_time = 60;
137	
138	    /* Parse the simple command-line */
139	    if (argc == 2)
140		disk = argv[1];
141	    else if (argc == 4) {
142		settle_time = atoi(argv[2]);
143		disk = argv[3];
144	    } else
145		usage();
146	
147	    if (!(fd = open(disk, O_RDONLY|O_NONBLOCK))) {
148		printf("Can't open %s, because: %s\n", disk, strerror(errno));
149		exit(-1);
150	    }
151	
152	    if (settle_time) {
153		printf("Waiting %d seconds for the system to settle down to "
154		       "'normal'\n", settle_time);
155		sleep(settle_time);
156	    } else
157		puts("Not waiting for system to settle down");
158	
159	    signal(SIGINT, ender);
160	
161	    measure(fd);
162	
163	    close(fd);
164	
165	    return 0;
166	}
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