summaryrefslogtreecommitdiff
path: root/miscutils/last_fancy.c
blob: d234a48bfc6ff583a4c6ba9d7eea93b969861c46 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
/* vi: set sw=4 ts=4: */
/*
 * (sysvinit like) last implementation
 *
 * Copyright (C) 2008 by Patricia Muscalu <patricia.muscalu@axis.com>
 *
 * Licensed under the GPLv2 or later, see the file LICENSE in this tarball.
 */

#include "libbb.h"
#include <utmp.h>

#ifndef SHUTDOWN_TIME
#  define SHUTDOWN_TIME 254
#endif

#define HEADER_FORMAT     "%-8.8s %-12.12s %-*.*s %-16.16s %-7.7s %s\n"
#define HEADER_LINE       "USER", "TTY", \
	INET_ADDRSTRLEN, INET_ADDRSTRLEN, "HOST", "LOGIN", "  TIME", ""
#define HEADER_LINE_WIDE  "USER", "TTY", \
	INET6_ADDRSTRLEN, INET6_ADDRSTRLEN, "HOST", "LOGIN", "  TIME", ""

enum {
	NORMAL,
	LOGGED,
	DOWN,
	REBOOT,
	CRASH,
	GONE
};

enum {
	LAST_OPT_W = (1 << 0),  /* -W wide            */
	LAST_OPT_f = (1 << 1),  /* -f input file      */
	LAST_OPT_H = (1 << 2),  /* -H header          */
};

#define show_wide (option_mask32 & LAST_OPT_W)

static void show_entry(struct utmp *ut, int state, time_t dur_secs)
{
	unsigned days, hours, mins;
	char duration[32];
	char login_time[17];
	char logout_time[8];
	const char *logout_str;
	const char *duration_str;

	safe_strncpy(login_time, ctime(&(ut->ut_time)), 17);
	snprintf(logout_time, 8, "- %s", ctime(&dur_secs) + 11);

	dur_secs = MAX(dur_secs - (time_t)ut->ut_tv.tv_sec, (time_t)0);
	/* unsigned int is easier to divide than time_t (which may be signed long) */
	mins = dur_secs / 60;
	days = mins / (24*60);
	mins = mins % (24*60);
	hours = mins / 60;
	mins = mins % 60;

//	if (days) {
		sprintf(duration, "(%u+%02u:%02u)", days, hours, mins);
//	} else {
//		sprintf(duration, " (%02u:%02u)", hours, mins);
//	}

	logout_str = logout_time;
	duration_str = duration;
	switch (state) {
	case NORMAL:
		break;
	case LOGGED:
		logout_str = "  still";
		duration_str = "logged in";
		break;
	case DOWN:
		logout_str = "- down ";
		break;
	case REBOOT:
		break;
	case CRASH:
		logout_str = "- crash";
		break;
	case GONE:
		logout_str = "   gone";
		duration_str = "- no logout";
		break;
	}

	printf(HEADER_FORMAT,
		   ut->ut_name,
		   ut->ut_line,
		   show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
		   show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
		   ut->ut_host,
		   login_time,
		   logout_str,
		   duration_str);
}

static int get_ut_type(struct utmp *ut)
{
	if (ut->ut_line[0] == '~') {
		if (strcmp(ut->ut_user, "shutdown") == 0) {
			return SHUTDOWN_TIME;
		}
		if (strcmp(ut->ut_user, "reboot") == 0) {
			return BOOT_TIME;
		}
		if (strcmp(ut->ut_user, "runlevel") == 0) {
			return RUN_LVL;
		}
		return ut->ut_type;
	}

	if (ut->ut_name[0] == 0) {
		return DEAD_PROCESS;
	}

	if ((ut->ut_type != DEAD_PROCESS)
	 && (strcmp(ut->ut_name, "LOGIN") != 0)
	 && ut->ut_name[0]
	 && ut->ut_line[0]
	) {
		ut->ut_type = USER_PROCESS;
	}

	if (strcmp(ut->ut_name, "date") == 0) {
		if (ut->ut_line[0] == '|') {
			return OLD_TIME;
		}
		if (ut->ut_line[0] == '{') {
			return NEW_TIME;
		}
	}
	return ut->ut_type;
}

static int is_runlevel_shutdown(struct utmp *ut)
{
	if (((ut->ut_pid & 255) == '0') || ((ut->ut_pid & 255) == '6')) {
		return 1;
	}

	return 0;
}

int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int last_main(int argc ATTRIBUTE_UNUSED, char **argv)
{
	struct utmp ut;
	const char *filename = _PATH_WTMP;
	llist_t *zlist;
	off_t pos;
	time_t start_time;
	time_t boot_time;
	time_t down_time;
	int file;
	unsigned opt;
	smallint going_down;
	smallint boot_down;

	opt = getopt32(argv, "Wf:" /* "H" */, &filename);
#ifdef BUT_UTIL_LINUX_LAST_HAS_NO_SUCH_OPT
	if (opt & LAST_OPT_H) {
		/* Print header line */
		if (opt & LAST_OPT_W) {
			printf(HEADER_FORMAT, HEADER_LINE_WIDE);
		} else {
			printf(HEADER_FORMAT, HEADER_LINE);
		}
	}
#endif

	file = xopen(filename, O_RDONLY);
	{
		/* in case the file is empty... */
		struct stat st;
		fstat(file, &st);
		start_time = st.st_ctime;
	}

	time(&down_time);
	going_down = 0;
	boot_down = NORMAL; /* 0 */
	zlist = NULL;
	boot_time = 0;
	/* get file size, rounding down to last full record */
	pos = xlseek(file, 0, SEEK_END) / sizeof(ut) * sizeof(ut);
	for (;;) {
		pos -= (off_t)sizeof(ut);
		if (pos < 0) {
			/* Beyond the beginning of the file boundary =>
			 * the whole file has been read. */
			break;
		}
		xlseek(file, pos, SEEK_SET);
		xread(file, &ut, sizeof(ut));
		/* rewritten by each record, eventially will have
		 * first record's ut_time: */
		start_time = ut.ut_time;

		switch (get_ut_type(&ut)) {
		case SHUTDOWN_TIME:
			down_time = ut.ut_time;
			boot_down = DOWN;
			going_down = 1;
			break;
		case RUN_LVL:
			if (is_runlevel_shutdown(&ut)) {
				down_time = ut.ut_time;
				going_down = 1;
				boot_down = DOWN;
			}
			break;
		case BOOT_TIME:
			strcpy(ut.ut_line, "system boot");
			show_entry(&ut, REBOOT, down_time);
			boot_down = CRASH;
			going_down = 1;
			break;
		case DEAD_PROCESS:
			if (!ut.ut_line[0]) {
				break;
			}
			/* add_entry */
			llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
			break;
		case USER_PROCESS: {
			int show;

			if (!ut.ut_line[0]) {
				break;
			}
			/* find_entry */
			show = 1;
			{
				llist_t *el, *next;
				for (el = zlist; el; el = next) {
					struct utmp *up = (struct utmp *)el->data;
					next = el->link;
					if (strncmp(up->ut_line, ut.ut_line, UT_LINESIZE) == 0) {
						if (show) {
							show_entry(&ut, NORMAL, up->ut_time);
							show = 0;
						}
						llist_unlink(&zlist, el);
						free(el->data);
						free(el);
					}
				}
			}

			if (show) {
				int state = boot_down;

				if (boot_time == 0) {
					state = LOGGED;
					/* Check if the process is alive */
					if ((ut.ut_pid > 0)
					 && (kill(ut.ut_pid, 0) != 0)
					 && (errno == ESRCH)) {
						state = GONE;
					}
				}
				show_entry(&ut, state, boot_time);
			}
			/* add_entry */
			llist_add_to(&zlist, memcpy(xmalloc(sizeof(ut)), &ut, sizeof(ut)));
			break;
		}
		}

		if (going_down) {
			boot_time = ut.ut_time;
			llist_free(zlist, free);
			zlist = NULL;
			going_down = 0;
		}
	}

	if (ENABLE_FEATURE_CLEAN_UP) {
		llist_free(zlist, free);
	}

	printf("\nwtmp begins %s", ctime(&start_time));

	if (ENABLE_FEATURE_CLEAN_UP)
		close(file);
	fflush_stdout_and_exit(EXIT_SUCCESS);
}