Commit | Line | Data |
---|---|---|
3b600ead TL |
1 | #include <signal.h> |
2 | #include <sys/types.h> | |
3 | #include <utmp.h> | |
4 | #include <setjmp.h> | |
5 | ||
6 | #define TABSIZ 100 | |
7 | #define ALL p = &itab[0]; p < &itab[TABSIZ]; p++ | |
8 | #define EVER ;; | |
9 | ||
10 | char shell[] = "/bin/sh"; | |
11 | char getty[] = "/etc/getty"; | |
12 | char minus[] = "-"; | |
13 | char runc[] = "/etc/rc"; | |
14 | char ifile[] = "/etc/ttys"; | |
15 | char utmp[] = "/etc/utmp"; | |
16 | char wtmpf[] = "/usr/adm/wtmp"; | |
17 | char ctty[] = "/dev/console"; | |
18 | char dev[] = "/dev/"; | |
19 | ||
20 | struct utmp wtmp; | |
21 | struct | |
22 | { | |
23 | char line[8]; | |
24 | char comn; | |
25 | char flag; | |
26 | } line; | |
27 | struct tab | |
28 | { | |
29 | char line[8]; | |
30 | char comn; | |
31 | int pid; | |
32 | } itab[TABSIZ]; | |
33 | ||
34 | int fi; | |
35 | char tty[20]; | |
36 | jmp_buf sjbuf; | |
37 | ||
38 | main() | |
39 | { | |
40 | int reset(); | |
41 | ||
42 | setjmp(sjbuf); | |
43 | signal(SIGHUP, reset); | |
44 | for(EVER) { | |
45 | shutdown(); | |
46 | single(); | |
47 | runcom(); | |
48 | merge(); | |
49 | multiple(); | |
50 | } | |
51 | } | |
52 | ||
53 | shutdown() | |
54 | { | |
55 | register i; | |
56 | register struct tab *p; | |
57 | ||
58 | signal(SIGINT, SIG_IGN); | |
59 | for(ALL) | |
60 | term(p); | |
61 | signal(SIGALRM, reset); | |
62 | alarm(60); | |
63 | for(i=0; i<5; i++) | |
64 | kill(-1, SIGKILL); | |
65 | while(wait((int *)0) != -1) | |
66 | ; | |
67 | alarm(0); | |
68 | signal(SIGALRM, SIG_DFL); | |
69 | for(i=0; i<10; i++) | |
70 | close(i); | |
71 | } | |
72 | ||
73 | single() | |
74 | { | |
75 | register pid; | |
76 | ||
77 | pid = fork(); | |
78 | if(pid == 0) { | |
79 | /* | |
80 | alarm(300); | |
81 | */ | |
82 | signal(SIGHUP, SIG_DFL); | |
83 | signal(SIGINT, SIG_DFL); | |
84 | signal(SIGALRM, SIG_DFL); | |
85 | open(ctty, 2); | |
86 | dup(0); | |
87 | dup(0); | |
88 | execl(shell, minus, (char *)0); | |
89 | exit(0); | |
90 | } | |
91 | while(wait((int *)0) != pid) | |
92 | ; | |
93 | } | |
94 | ||
95 | runcom() | |
96 | { | |
97 | register pid; | |
98 | ||
99 | pid = fork(); | |
100 | if(pid == 0) { | |
101 | open("/", 0); | |
102 | dup(0); | |
103 | dup(0); | |
104 | execl(shell, shell, runc, (char *)0); | |
105 | exit(0); | |
106 | } | |
107 | while(wait((int *)0) != pid) | |
108 | ; | |
109 | } | |
110 | ||
111 | multiple() | |
112 | { | |
113 | register struct tab *p; | |
114 | register pid; | |
115 | ||
116 | for(EVER) { | |
117 | pid = wait((int *)0); | |
118 | if(pid == -1) | |
119 | return; | |
120 | for(ALL) | |
121 | if(p->pid == pid || p->pid == -1) { | |
122 | rmut(p); | |
123 | dfork(p); | |
124 | } | |
125 | } | |
126 | } | |
127 | ||
128 | term(p) | |
129 | register struct tab *p; | |
130 | { | |
131 | ||
132 | if(p->pid != 0) { | |
133 | rmut(p); | |
134 | kill(p->pid, SIGKILL); | |
135 | } | |
136 | p->pid = 0; | |
137 | p->line[0] = 0; | |
138 | } | |
139 | ||
140 | rline() | |
141 | { | |
142 | register c, i; | |
143 | ||
144 | c = get(); | |
145 | if(c < 0) | |
146 | return(0); | |
147 | if(c == 0) | |
148 | goto bad; | |
149 | line.flag = c; | |
150 | c = get(); | |
151 | if(c <= 0) | |
152 | goto bad; | |
153 | line.comn = c; | |
154 | for(i=0; i<8; i++) | |
155 | line.line[i] = 0; | |
156 | for(i=0; i<7; i++) { | |
157 | c = get(); | |
158 | if(c <= 0) | |
159 | break; | |
160 | line.line[i] = c; | |
161 | } | |
162 | while(c > 0) | |
163 | c = get(); | |
164 | maktty(line.line); | |
165 | if(access(tty, 06) < 0) | |
166 | goto bad; | |
167 | return(1); | |
168 | ||
169 | bad: | |
170 | line.flag = '0'; | |
171 | return(1); | |
172 | } | |
173 | ||
174 | maktty(lin) | |
175 | char *lin; | |
176 | { | |
177 | register i, j; | |
178 | ||
179 | for(i=0; dev[i]; i++) | |
180 | tty[i] = dev[i]; | |
181 | for(j=0; lin[j]; j++) { | |
182 | tty[i] = lin[j]; | |
183 | i++; | |
184 | } | |
185 | tty[i] = 0; | |
186 | } | |
187 | ||
188 | get() | |
189 | { | |
190 | char b; | |
191 | ||
192 | if(read(fi, &b, 1) != 1) | |
193 | return(-1); | |
194 | if(b == '\n') | |
195 | return(0); | |
196 | return(b); | |
197 | } | |
198 | ||
199 | merge() | |
200 | { | |
201 | register struct tab *p, *q; | |
202 | register i; | |
203 | ||
204 | close(creat(utmp, 0644)); | |
205 | signal(SIGINT, merge); | |
206 | fi = open(ifile, 0); | |
207 | if(fi < 0) | |
208 | return; | |
209 | q = &itab[0]; | |
210 | while(rline()) { | |
211 | if(line.flag == '0') | |
212 | continue; | |
213 | for(ALL) { | |
214 | if(p->line[0] != 0) | |
215 | for(i=0; i<8; i++) | |
216 | if(p->line[i] != line.line[i]) | |
217 | goto contin; | |
218 | if(p >= q) { | |
219 | i = p->pid; | |
220 | p->pid = q->pid; | |
221 | q->pid = i; | |
222 | for(i=0; i<8; i++) | |
223 | p->line[i] = q->line[i]; | |
224 | p->comn = q->comn; | |
225 | for(i=0; i<8; i++) | |
226 | q->line[i] = line.line[i]; | |
227 | q->comn = line.comn; | |
228 | q++; | |
229 | } | |
230 | break; | |
231 | contin: | |
232 | ; | |
233 | } | |
234 | } | |
235 | close(fi); | |
236 | for(; q < &itab[TABSIZ]; q++) | |
237 | term(q); | |
238 | for(ALL) | |
239 | if(p->line[0] != 0 && p->pid == 0) | |
240 | dfork(p); | |
241 | } | |
242 | ||
243 | dfork(p) | |
244 | struct tab *p; | |
245 | { | |
246 | register pid; | |
247 | ||
248 | pid = fork(); | |
249 | if(pid == 0) { | |
250 | signal(SIGHUP, SIG_DFL); | |
251 | signal(SIGINT, SIG_DFL); | |
252 | maktty(p->line); | |
253 | chown(tty, 0, 0); | |
254 | chmod(tty, 0622); | |
255 | open(tty, 2); | |
256 | dup(0); | |
257 | dup(0); | |
258 | tty[0] = p->comn; | |
259 | tty[1] = 0; | |
260 | execl(getty, minus, tty, (char *)0); | |
261 | exit(0); | |
262 | } | |
263 | p->pid = pid; | |
264 | } | |
265 | ||
266 | rmut(p) | |
267 | register struct tab *p; | |
268 | { | |
269 | register i, f; | |
270 | ||
271 | f = open(utmp, 2); | |
272 | if(f >= 0) { | |
273 | while(read(f, (char *)&wtmp, sizeof(wtmp)) == sizeof(wtmp)) { | |
274 | for(i=0; i<8; i++) | |
275 | if(wtmp.ut_line[i] != p->line[i]) | |
276 | goto contin; | |
277 | lseek(f, (long)-sizeof(wtmp), 1); | |
278 | for(i=0; i<8; i++) | |
279 | wtmp.ut_name[i] = 0; | |
280 | time(&wtmp.ut_time); | |
281 | write(f, (char *)&wtmp, sizeof(wtmp)); | |
282 | contin:; | |
283 | } | |
284 | close(f); | |
285 | } | |
286 | f = open(wtmpf, 1); | |
287 | if (f >= 0) { | |
288 | for(i=0; i<8; i++) { | |
289 | wtmp.ut_name[i] = 0; | |
290 | wtmp.ut_line[i] = p->line[i]; | |
291 | } | |
292 | time(&wtmp.ut_time); | |
293 | lseek(f, (long)0, 2); | |
294 | write(f, (char *)&wtmp, sizeof(wtmp)); | |
295 | close(f); | |
296 | } | |
297 | } | |
298 | ||
299 | reset() | |
300 | { | |
301 | longjmp(sjbuf, 1); | |
302 | } |