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10#include "libbb.h"
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14
15#ifndef SHUTDOWN_TIME
16# define SHUTDOWN_TIME 254
17#endif
18
19#define HEADER_FORMAT "%-8.8s %-12.12s %-*.*s %-16.16s %-7.7s %s\n"
20#define HEADER_LINE "USER", "TTY", \
21 INET_ADDRSTRLEN, INET_ADDRSTRLEN, "HOST", "LOGIN", " TIME", ""
22#define HEADER_LINE_WIDE "USER", "TTY", \
23 INET6_ADDRSTRLEN, INET6_ADDRSTRLEN, "HOST", "LOGIN", " TIME", ""
24
25#if !defined __UT_LINESIZE && defined UT_LINESIZE
26# define __UT_LINESIZE UT_LINESIZE
27#endif
28
29enum {
30 NORMAL,
31 LOGGED,
32 DOWN,
33 REBOOT,
34 CRASH,
35 GONE
36};
37
38enum {
39 LAST_OPT_W = (1 << 0),
40 LAST_OPT_f = (1 << 1),
41 LAST_OPT_H = (1 << 2),
42};
43
44#define show_wide (option_mask32 & LAST_OPT_W)
45
46static void show_entry(struct utmpx *ut, int state, time_t dur_secs)
47{
48 unsigned days, hours, mins;
49 char duration[sizeof("(%u+02:02)") + sizeof(int)*3];
50 char login_time[17];
51 char logout_time[8];
52 const char *logout_str;
53 const char *duration_str;
54 time_t tmp;
55
56
57
58 tmp = ut->ut_tv.tv_sec;
59 safe_strncpy(login_time, ctime(&tmp), 17);
60 tmp = dur_secs;
61 snprintf(logout_time, 8, "- %s", ctime(&tmp) + 11);
62
63 dur_secs = MAX(dur_secs - (time_t)ut->ut_tv.tv_sec, (time_t)0);
64
65 mins = dur_secs / 60;
66 days = mins / (24*60);
67 mins = mins % (24*60);
68 hours = mins / 60;
69 mins = mins % 60;
70
71
72 sprintf(duration, "(%u+%02u:%02u)", days, hours, mins);
73
74
75
76
77 logout_str = logout_time;
78 duration_str = duration;
79 switch (state) {
80 case NORMAL:
81 break;
82 case LOGGED:
83 logout_str = " still";
84 duration_str = "logged in";
85 break;
86 case DOWN:
87 logout_str = "- down ";
88 break;
89 case REBOOT:
90 break;
91 case CRASH:
92 logout_str = "- crash";
93 break;
94 case GONE:
95 logout_str = " gone";
96 duration_str = "- no logout";
97 break;
98 }
99
100 printf(HEADER_FORMAT,
101 ut->ut_user,
102 ut->ut_line,
103 show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
104 show_wide ? INET6_ADDRSTRLEN : INET_ADDRSTRLEN,
105 ut->ut_host,
106 login_time,
107 logout_str,
108 duration_str);
109}
110
111static int get_ut_type(struct utmpx *ut)
112{
113 if (ut->ut_line[0] == '~') {
114 if (strcmp(ut->ut_user, "shutdown") == 0) {
115 return SHUTDOWN_TIME;
116 }
117 if (strcmp(ut->ut_user, "reboot") == 0) {
118 return BOOT_TIME;
119 }
120 if (strcmp(ut->ut_user, "runlevel") == 0) {
121 return RUN_LVL;
122 }
123 return ut->ut_type;
124 }
125
126 if (ut->ut_user[0] == 0) {
127 return DEAD_PROCESS;
128 }
129
130 if ((ut->ut_type != DEAD_PROCESS)
131 && (strcmp(ut->ut_user, "LOGIN") != 0)
132 && ut->ut_user[0]
133 && ut->ut_line[0]
134 ) {
135 ut->ut_type = USER_PROCESS;
136 }
137
138 if (strcmp(ut->ut_user, "date") == 0) {
139 if (ut->ut_line[0] == '|') {
140 return OLD_TIME;
141 }
142 if (ut->ut_line[0] == '{') {
143 return NEW_TIME;
144 }
145 }
146 return ut->ut_type;
147}
148
149static int is_runlevel_shutdown(struct utmpx *ut)
150{
151 if (((ut->ut_pid & 255) == '0') || ((ut->ut_pid & 255) == '6')) {
152 return 1;
153 }
154
155 return 0;
156}
157
158int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
159int last_main(int argc UNUSED_PARAM, char **argv)
160{
161 struct utmpx ut;
162 const char *filename = _PATH_WTMP;
163 llist_t *zlist;
164 off_t pos;
165 time_t start_time;
166 time_t boot_time;
167 time_t down_time;
168 int file;
169 smallint going_down;
170 smallint boot_down;
171
172 getopt32(argv, "Wf:" , &filename);
173#ifdef BUT_UTIL_LINUX_LAST_HAS_NO_SUCH_OPT
174 if (opt & LAST_OPT_H) {
175
176 if (opt & LAST_OPT_W) {
177 printf(HEADER_FORMAT, HEADER_LINE_WIDE);
178 } else {
179 printf(HEADER_FORMAT, HEADER_LINE);
180 }
181 }
182#endif
183
184 file = xopen(filename, O_RDONLY);
185 {
186
187 struct stat st;
188 fstat(file, &st);
189 start_time = st.st_ctime;
190 }
191
192 time(&down_time);
193 going_down = 0;
194 boot_down = NORMAL;
195 zlist = NULL;
196 boot_time = 0;
197
198 pos = xlseek(file, 0, SEEK_END) / sizeof(ut) * sizeof(ut);
199 for (;;) {
200 pos -= (off_t)sizeof(ut);
201 if (pos < 0) {
202
203
204 break;
205 }
206 xlseek(file, pos, SEEK_SET);
207 xread(file, &ut, sizeof(ut));
208
209
210 start_time = ut.ut_tv.tv_sec;
211
212 switch (get_ut_type(&ut)) {
213 case SHUTDOWN_TIME:
214 down_time = ut.ut_tv.tv_sec;
215 boot_down = DOWN;
216 going_down = 1;
217 break;
218 case RUN_LVL:
219 if (is_runlevel_shutdown(&ut)) {
220 down_time = ut.ut_tv.tv_sec;
221 going_down = 1;
222 boot_down = DOWN;
223 }
224 break;
225 case BOOT_TIME:
226 strcpy(ut.ut_line, "system boot");
227 show_entry(&ut, REBOOT, down_time);
228 boot_down = CRASH;
229 going_down = 1;
230 break;
231 case DEAD_PROCESS:
232 if (!ut.ut_line[0]) {
233 break;
234 }
235
236 llist_add_to(&zlist, xmemdup(&ut, sizeof(ut)));
237 break;
238 case USER_PROCESS: {
239 int show;
240
241 if (!ut.ut_line[0]) {
242 break;
243 }
244
245 show = 1;
246 {
247 llist_t *el, *next;
248 for (el = zlist; el; el = next) {
249 struct utmpx *up = (struct utmpx *)el->data;
250 next = el->link;
251 if (strncmp(up->ut_line, ut.ut_line, __UT_LINESIZE) == 0) {
252 if (show) {
253 show_entry(&ut, NORMAL, up->ut_tv.tv_sec);
254 show = 0;
255 }
256 llist_unlink(&zlist, el);
257 free(el->data);
258 free(el);
259 }
260 }
261 }
262
263 if (show) {
264 int state = boot_down;
265
266 if (boot_time == 0) {
267 state = LOGGED;
268
269 if ((ut.ut_pid > 0)
270 && (kill(ut.ut_pid, 0) != 0)
271 && (errno == ESRCH)) {
272 state = GONE;
273 }
274 }
275 show_entry(&ut, state, boot_time);
276 }
277
278 llist_add_to(&zlist, xmemdup(&ut, sizeof(ut)));
279 break;
280 }
281 }
282
283 if (going_down) {
284 boot_time = ut.ut_tv.tv_sec;
285 llist_free(zlist, free);
286 zlist = NULL;
287 going_down = 0;
288 }
289 }
290
291 if (ENABLE_FEATURE_CLEAN_UP) {
292 llist_free(zlist, free);
293 }
294
295 printf("\nwtmp begins %s", ctime(&start_time));
296
297 if (ENABLE_FEATURE_CLEAN_UP)
298 close(file);
299 fflush_stdout_and_exit(EXIT_SUCCESS);
300}
301
