1 #include "stdinc.h"
2 
3 #include "9.h"
4 
5 typedef struct Srv Srv;
6 struct Srv {
7 	int	fd;
8 	int	srvfd;
9 	char*	service;
10 	char*	mntpnt;
11 
12 	Srv*	next;
13 	Srv*	prev;
14 };
15 
16 static struct {
17 	RWLock	lock;
18 
19 	Srv*	head;
20 	Srv*	tail;
21 } sbox;
22 
23 #ifndef PLAN9PORT
24 static int
25 srvFd(char* name, int mode, int fd, char** mntpnt)
26 {
27 	int n, srvfd;
28 	char *p, buf[10];
29 
30 	/*
31 	 * Drop a file descriptor with given name and mode into /srv.
32 	 * Create with ORCLOSE and don't close srvfd so it will be removed
33 	 * automatically on process exit.
34 	 */
35 	p = smprint("/srv/%s", name);
36 	if((srvfd = create(p, ORCLOSE|OWRITE, mode)) < 0){
37 		vtfree(p);
38 		p = smprint("#s/%s", name);
39 		if((srvfd = create(p, ORCLOSE|OWRITE, mode)) < 0){
40 			werrstr("create %s: %r", p);
41 			vtfree(p);
42 			return -1;
43 		}
44 	}
45 
46 	n = snprint(buf, sizeof(buf), "%d", fd);
47 	if(write(srvfd, buf, n) < 0){
48 		close(srvfd);
49 		werrstr("write %s: %r", p);
50 		vtfree(p);
51 		return -1;
52 	}
53 
54 	*mntpnt = p;
55 
56 	return srvfd;
57 }
58 #endif
59 
60 static void
61 srvFree(Srv* srv)
62 {
63 	if(srv->prev != nil)
64 		srv->prev->next = srv->next;
65 	else
66 		sbox.head = srv->next;
67 	if(srv->next != nil)
68 		srv->next->prev = srv->prev;
69 	else
70 		sbox.tail = srv->prev;
71 
72 	if(srv->srvfd != -1)
73 		close(srv->srvfd);
74 	vtfree(srv->service);
75 	vtfree(srv->mntpnt);
76 	vtfree(srv);
77 }
78 
79 static Srv*
80 srvAlloc(char* service, int mode, int fd)
81 {
82 	Dir *dir;
83 	Srv *srv;
84 	int srvfd;
85 	char *mntpnt;
86 
87 	wlock(&sbox.lock);
88 	for(srv = sbox.head; srv != nil; srv = srv->next){
89 		if(strcmp(srv->service, service) != 0)
90 			continue;
91 		/*
92 		 * If the service exists, but is stale,
93 		 * free it up and let the name be reused.
94 		 */
95 		if((dir = dirfstat(srv->srvfd)) != nil){
96 			free(dir);
97 			werrstr("srv: already serving '%s'", service);
98 			wunlock(&sbox.lock);
99 			return nil;
100 		}
101 		srvFree(srv);
102 		break;
103 	}
104 
105 #ifdef PLAN9PORT
106 	mntpnt = nil;
107 	if((srvfd = post9pservice(fd, service, mntpnt)) < 0){
108 #else
109 	if((srvfd = srvFd(service, mode, fd, &mntpnt)) < 0){
110 #endif
111 		wunlock(&sbox.lock);
112 		return nil;
113 	}
114 	close(fd);
115 
116 	srv = vtmallocz(sizeof(Srv));
117 	srv->srvfd = srvfd;
118 	srv->service = vtstrdup(service);
119 	srv->mntpnt = mntpnt;
120 
121 	if(sbox.tail != nil){
122 		srv->prev = sbox.tail;
123 		sbox.tail->next = srv;
124 	}
125 	else{
126 		sbox.head = srv;
127 		srv->prev = nil;
128 	}
129 	sbox.tail = srv;
130 	wunlock(&sbox.lock);
131 
132 	return srv;
133 }
134 
135 static int
136 cmdSrv(int argc, char* argv[])
137 {
138 	Con *con;
139 	Srv *srv;
140 	char *usage = "usage: srv [-APWdp] [service]";
141 	int conflags, dflag, fd[2], mode, pflag, r;
142 
143 	dflag = 0;
144 	pflag = 0;
145 	conflags = 0;
146 	mode = 0666;
147 
148 	ARGBEGIN{
149 	default:
150 		return cliError(usage);
151 	case 'A':
152 		conflags |= ConNoAuthCheck;
153 		break;
154 	case 'I':
155 		conflags |= ConIPCheck;
156 		break;
157 	case 'N':
158 		conflags |= ConNoneAllow;
159 		break;
160 	case 'P':
161 		conflags |= ConNoPermCheck;
162 		mode = 0600;
163 		break;
164 	case 'W':
165 		conflags |= ConWstatAllow;
166 		mode = 0600;
167 		break;
168 	case 'd':
169 		dflag = 1;
170 		break;
171 	case 'p':
172 		pflag = 1;
173 		mode = 0600;
174 		break;
175 	}ARGEND
176 
177 	if(pflag && (conflags&ConNoPermCheck)){
178 		werrstr("srv: cannot use -P with -p");
179 		return 0;
180 	}
181 
182 	switch(argc){
183 	default:
184 		return cliError(usage);
185 	case 0:
186 		rlock(&sbox.lock);
187 		for(srv = sbox.head; srv != nil; srv = srv->next)
188 			consPrint("\t%s\t%d\n", srv->service, srv->srvfd);
189 		runlock(&sbox.lock);
190 
191 		return 1;
192 	case 1:
193 		if(!dflag)
194 			break;
195 
196 		wlock(&sbox.lock);
197 		for(srv = sbox.head; srv != nil; srv = srv->next){
198 			if(strcmp(srv->service, argv[0]) != 0)
199 				continue;
200 			srvFree(srv);
201 			break;
202 		}
203 		wunlock(&sbox.lock);
204 
205 		if(srv == nil){
206 			werrstr("srv: '%s' not found", argv[0]);
207 			return 0;
208 		}
209 
210 		return 1;
211 	}
212 
213 #ifdef PLAN9PORT	/* fossilcons unsupported */
214 	if(pflag)
215 		return 1;
216 #endif
217 
218 	if(pipe(fd) < 0){
219 		werrstr("srv pipe: %r");
220 		return 0;
221 	}
222 	if((srv = srvAlloc(argv[0], mode, fd[0])) == nil){
223 		close(fd[0]); close(fd[1]);
224 		return 0;
225 	}
226 
227 	if(pflag)
228 		r = consOpen(fd[1], srv->srvfd, -1);
229 	else{
230 		con = conAlloc(fd[1], srv->mntpnt, conflags);
231 		if(con == nil)
232 			r = 0;
233 		else
234 			r = 1;
235 	}
236 	if(r == 0){
237 		close(fd[1]);
238 		wlock(&sbox.lock);
239 		srvFree(srv);
240 		wunlock(&sbox.lock);
241 	}
242 
243 	return r;
244 }
245 
246 int
247 srvInit(void)
248 {
249 	cliAddCmd("srv", cmdSrv);
250 
251 	return 1;
252 }