1 #include <u.h>
2 #include <sys/time.h>
3 #include <sys/stat.h>
4 #include <sys/resource.h>
5 #include <errno.h>
6 #include <fcntl.h>
7 #include <libc.h>
8 #include "rc.h"
9 #include "exec.h"
10 #include "io.h"
11 #include "fns.h"
12 #include "getflags.h"
13 
14 extern char **mkargv(word*);
15 extern int mapfd(int);
16 
17 static char *eargs = "cdflmnstuv";
18 static int rlx[] = {
19 	RLIMIT_CORE,
20 	RLIMIT_DATA,
21 	RLIMIT_FSIZE,
22 #ifdef RLIMIT_MEMLOCK
23 	RLIMIT_MEMLOCK,
24 #else
25 	0,
26 #endif
27 #ifdef RLIMIT_RSS
28 	RLIMIT_RSS,
29 #else
30 	0,
31 #endif
32 	RLIMIT_NOFILE,
33 	RLIMIT_STACK,
34 	RLIMIT_CPU,
35 #ifdef RLIMIT_NPROC
36 	RLIMIT_NPROC,
37 #else
38 	0,
39 #endif
40 #ifdef RLIMIT_RSS
41 	RLIMIT_RSS,
42 #else
43 	0,
44 #endif
45 };
46 
47 static void
48 eusage(void)
49 {
50 	fprint(mapfd(2), "usage: ulimit [-SHa%s [limit]]\n", eargs);
51 }
52 
53 #define Notset -4
54 #define Unlimited -3
55 #define Hard -2
56 #define Soft -1
57 
58 void
59 execulimit(void)
60 {
61 	rlim_t n;
62 	int fd, argc, sethard, setsoft, limit;
63 	int flag[256];
64 	char **argv, **oargv, *p;
65 	char *argv0;
66 	struct rlimit rl;
67 
68 	argv0 = nil;
69 	setstatus("");
70 	oargv = mkargv(runq->argv->words);
71 	argv = oargv+1;
72 	for(argc=0; argv[argc]; argc++)
73 		;
74 
75 	memset(flag, 0, sizeof flag);
76 	ARGBEGIN{
77 	default:
78 		if(strchr(eargs, ARGC()) == nil){
79 			eusage();
80 			return;
81 		}
82 	case 'S':
83 	case 'H':
84 	case 'a':
85 		flag[ARGC()] = 1;
86 		break;
87 	}ARGEND
88 
89 	if(argc > 1){
90 		eusage();
91 		goto out;
92 	}
93 
94 	fd = mapfd(1);
95 
96 	sethard = 1;
97 	setsoft = 1;
98 	if(flag['S'] && flag['H'])
99 		;
100 	else if(flag['S'])
101 		sethard = 0;
102 	else if(flag['H'])
103 		setsoft = 0;
104 
105 	limit = Notset;
106 	if(argc>0){
107 		if(strcmp(argv[0], "unlimited") == 0)
108 			limit = Unlimited;
109 		else if(strcmp(argv[0], "hard") == 0)
110 			limit = Hard;
111 		else if(strcmp(argv[0], "soft") == 0)
112 			limit = Soft;
113 		else if((limit = strtol(argv[0], &p, 0)) < 0 || *p != 0){
114 			eusage();
115 			goto out;
116 		}
117 	}
118 	if(flag['a']){
119 		for(p=eargs; *p; p++){
120 			getrlimit(rlx[p-eargs], &rl);
121 			n = flag['H'] ? rl.rlim_max : rl.rlim_cur;
122 			if(n == RLIM_INFINITY)
123 				fprint(fd, "ulimit -%c unlimited\n", *p);
124 			else
125 				fprint(fd, "ulimit -%c %llud\n", *p, (uvlong)n);
126 		}
127 		goto out;
128 	}
129 	for(p=eargs; *p; p++){
130 		if(flag[(uchar)*p]){
131 			n = 0;
132 			getrlimit(rlx[p-eargs], &rl);
133 			switch(limit){
134 			case Notset:
135 				n = flag['H'] ? rl.rlim_max : rl.rlim_cur;
136 				if(n == RLIM_INFINITY)
137 					fprint(fd, "ulimit -%c unlimited\n", *p);
138 				else
139 					fprint(fd, "ulimit -%c %llud\n", *p, (uvlong)n);
140 				break;
141 			case Hard:
142 				n = rl.rlim_max;
143 				goto set;
144 			case Soft:
145 				n = rl.rlim_cur;
146 				goto set;
147 			case Unlimited:
148 				n = RLIM_INFINITY;
149 				goto set;
150 			default:
151 				n = limit;
152 			set:
153 				if(setsoft)
154 					rl.rlim_cur = n;
155 				if(sethard)
156 					rl.rlim_max = n;
157 				if(setrlimit(rlx[p-eargs], &rl) < 0)
158 					fprint(mapfd(2), "setrlimit: %r\n");
159 			}
160 		}
161 	}
162 
163 out:
164 	free(oargv);
165 	poplist();
166 	flush(err);
167 }
168 
169 void
170 execumask(void)
171 {
172 	int n, argc;
173 	char **argv, **oargv, *p;
174 	char *argv0;
175 
176 	argv0 = nil;
177 	setstatus("");
178 	oargv = mkargv(runq->argv->words);
179 	argv = oargv+1;
180 	for(argc=0; argv[argc]; argc++)
181 		;
182 
183 	ARGBEGIN{
184 	default:
185 	usage:
186 		fprint(mapfd(2), "usage: umask [mode]\n");
187 		goto out;
188 	}ARGEND
189 
190 	if(argc > 1)
191 		goto usage;
192 
193 	if(argc == 1){
194 		n = strtol(argv[0], &p, 8);
195 		if(*p != 0 || p == argv[0])
196 			goto usage;
197 		umask(n);
198 		goto out;
199 	}
200 
201 	n = umask(0);
202 	umask(n);
203 	if(n < 0){
204 		fprint(mapfd(2), "umask: %r\n");
205 		goto out;
206 	}
207 
208 	fprint(mapfd(1), "umask %03o\n", n);
209 
210 out:
211 	free(oargv);
212 	poplist();
213 	flush(err);
214 }
215 
216 /*
217  * Cope with non-blocking read.
218  */
219 long
220 readnb(int fd, char *buf, long cnt)
221 {
222 	int n, didreset;
223 	int flgs;
224 
225 	didreset = 0;
226 again:
227 	n = read(fd, buf, cnt);
228 	if(n == -1)
229 	if(errno == EAGAIN){
230 		if(!didreset){
231 			if((flgs = fcntl(fd, F_GETFL, 0)) == -1)
232 				return -1;
233 			flgs &= ~O_NONBLOCK;
234 			if(fcntl(fd, F_SETFL, flgs) == -1)
235 				return -1;
236 			didreset = 1;
237 		}
238 		goto again;
239 	}
240 
241 	return n;
242 }