1 | |
---|
2 | #include <stdio.h> |
---|
3 | #include <unistd.h> |
---|
4 | #include <stdlib.h> |
---|
5 | #include <string.h> |
---|
6 | #include <signal.h> |
---|
7 | #include <sys/types.h> |
---|
8 | #include <sys/socket.h> |
---|
9 | #include <sys/wait.h> |
---|
10 | #include <sys/select.h> |
---|
11 | #include <sys/time.h> |
---|
12 | #include <arpa/inet.h> |
---|
13 | #include <fcntl.h> |
---|
14 | #include <netinet/in.h> |
---|
15 | #include <getopt.h> |
---|
16 | #include <errno.h> |
---|
17 | |
---|
18 | |
---|
19 | static void |
---|
20 | Help(const char *program) |
---|
21 | { |
---|
22 | fprintf(stderr, |
---|
23 | "Syntax: %s [-d] [-f serversFile] [-x numVideoCards]\n", program); |
---|
24 | exit(1); |
---|
25 | } |
---|
26 | |
---|
27 | typedef struct { |
---|
28 | const char *name; |
---|
29 | int port; |
---|
30 | int argc; |
---|
31 | char **argv; |
---|
32 | int f; |
---|
33 | } RenderServer; |
---|
34 | |
---|
35 | static Tcl_HashTable serverTable; |
---|
36 | |
---|
37 | static int |
---|
38 | RegisterServerCmd(ClientData clientData, Tcl_Interp *interp, int objc, |
---|
39 | Tcl_Obj *const *objv) |
---|
40 | { |
---|
41 | Tcl_Obj *objPtr; |
---|
42 | const char *serverName; |
---|
43 | int bool, isNew; |
---|
44 | int f; |
---|
45 | int port; |
---|
46 | struct sockaddr_in addr; |
---|
47 | RenderServer *serverPtr; |
---|
48 | Tcl_HashEntry *hPtr; |
---|
49 | |
---|
50 | if (objc != 4) { |
---|
51 | Tcl_AppendResult("wrong # args: should be \"", Tcl_GetString(objv[0]), |
---|
52 | " serverName port cmd", (char *)NULL); |
---|
53 | return TCL_ERROR; |
---|
54 | } |
---|
55 | serverName = Tcl_GetString(objv[1]); |
---|
56 | if (Tcl_GetInt(interp, objv[2], &port) != TCL_OK) { |
---|
57 | return TCL_ERROR; |
---|
58 | } |
---|
59 | hPtr = Tcl_CreateHashEntry(&serverTable, (char *)port, &isNew); |
---|
60 | if (!isNew) { |
---|
61 | Tcl_AppendResult("a server is already listening on port ", |
---|
62 | Tcl_GetString(objv[2]), (char *)NULL); |
---|
63 | return TCL_ERROR; |
---|
64 | } |
---|
65 | objPtr = Tcl_SubstObj(interp, objv[3], |
---|
66 | TCL_SUBST_VARIABLES | TCL_SUBST_BACKSLASHES); |
---|
67 | if (Tcl_SplitList(interp, Tcl_GetString(objPtr), &argc, &argv) != TCL_OK) { |
---|
68 | return TCL_ERROR; |
---|
69 | } |
---|
70 | |
---|
71 | // Create a socket for listening. |
---|
72 | f = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); |
---|
73 | if (f < 0) { |
---|
74 | Tcl_AppendResult(interp, "can't create listerner socket for \"", |
---|
75 | serverName, "\": ", Tcl_PosixError(interp), (char *)NULL); |
---|
76 | return TCL_ERROR; |
---|
77 | } |
---|
78 | |
---|
79 | // If program is killed, drop the socket address reservation immediately. |
---|
80 | bool = 1; |
---|
81 | status = setsockopt(f, SOL_SOCKET, SO_REUSEADDR, &bool, sizeof(bool)); |
---|
82 | if (status < 0) { |
---|
83 | Tcl_AppendResult(interp, "can't create set socket option for \"", |
---|
84 | serverName, "\": ", Tcl_PosixError(interp), (char *)NULL); |
---|
85 | return TCL_ERROR; |
---|
86 | } |
---|
87 | |
---|
88 | /* Bind this address to the socket. */ |
---|
89 | addr.sin_family = AF_INET; |
---|
90 | addr.sin_port = htons(port); |
---|
91 | addr.sin_addr.s_addr = htonl(INADDR_ANY); |
---|
92 | status = bind(f, (struct sockaddr *)&addr, sizeof(addr)); |
---|
93 | if (status < 0) { |
---|
94 | Tcl_AppendResult(interp, "can't bind to socket for \"", |
---|
95 | serverName, "\": ", Tcl_PosixError(interp), (char *)NULL); |
---|
96 | return TCL_ERROR; |
---|
97 | } |
---|
98 | /* Listen on the specified port. */ |
---|
99 | status = listen(f, 5); |
---|
100 | if (status < 0) { |
---|
101 | Tcl_AppendResult(interp, "can't listen to socket for \"", |
---|
102 | serverName, "\": ", Tcl_PosixError(interp), (char *)NULL); |
---|
103 | return TCL_ERROR; |
---|
104 | } |
---|
105 | serverPtr = malloc(sizeof(RenderServer)); |
---|
106 | if (serverPtr == NULL) { |
---|
107 | Tcl_AppendResult(interp, "can't allocate structure for \"", |
---|
108 | serverName, "\": ", Tcl_PosixError(interp), (char *)NULL); |
---|
109 | return TCL_ERROR; |
---|
110 | } |
---|
111 | serverPtr->name = strdup(serverName); |
---|
112 | serverPtr->argv = argv; |
---|
113 | serverPtr->argc = argc; |
---|
114 | serverPtr->listenerFd = f; |
---|
115 | return TCL_OK; |
---|
116 | } |
---|
117 | |
---|
118 | static int |
---|
119 | ParseServersFile(const char *fileName) |
---|
120 | { |
---|
121 | Tcl_Interp *interp; |
---|
122 | |
---|
123 | interp = Tcl_CreateInterp(); |
---|
124 | Tcl_MakeSafe(interp); |
---|
125 | Tcl_CreateObjCommand(interp, "register_server", RegisterServerCmd, NULL, |
---|
126 | NULL); |
---|
127 | if (Tcl_EvalFile(interp, fileName) != TCL_OK) { |
---|
128 | ERROR("can't add server: %s", Tcl_GetString(Tcl_GetObjResult(interp))); |
---|
129 | return FALSE; |
---|
130 | } |
---|
131 | Tcl_DeleteInterp(interp); |
---|
132 | return TRUE; |
---|
133 | } |
---|
134 | |
---|
135 | int |
---|
136 | main(int argc, char *argv[]) |
---|
137 | { |
---|
138 | int status; |
---|
139 | struct sockaddr_in recvAddr; |
---|
140 | int serverFds[FD_SETSIZE]; |
---|
141 | int recvPort; |
---|
142 | int n; |
---|
143 | char displayVar[200]; |
---|
144 | int maxCards; |
---|
145 | int dispNum; |
---|
146 | Tcl_HashEntry *hPtr; |
---|
147 | Tcl_HashSearch iter; |
---|
148 | |
---|
149 | dispNum = 0; |
---|
150 | maxCards = 1; |
---|
151 | recvPort = 2000; |
---|
152 | debug_flags = FALSE; |
---|
153 | strcpy(displayVar, "DISPLAY=:0.0"); |
---|
154 | if (putenv(displayVar) < 0) { |
---|
155 | ERROR("can't set DISPLAY variable: ", strerror(errno)); |
---|
156 | exit(1); |
---|
157 | } |
---|
158 | Tcl_InitHashTable(&serverTable, TCL_ONE_WORD_KEYS); |
---|
159 | while (1) { |
---|
160 | int c; |
---|
161 | int option_index = 0; |
---|
162 | struct option long_options[] = { |
---|
163 | // name, has_arg, flag, val |
---|
164 | { 0,0,0,0 }, |
---|
165 | }; |
---|
166 | |
---|
167 | c = getopt_long(argc, argv, "+p:x:d", long_options, &option_index); |
---|
168 | if (c == -1) { |
---|
169 | break; |
---|
170 | } |
---|
171 | |
---|
172 | switch(c) { |
---|
173 | case 'x': /* Number of video cards */ |
---|
174 | maxCards = strtoul(optarg, 0, 0); |
---|
175 | if ((maxCards < 1) || (maxCards > 10)) { |
---|
176 | fprintf(stderr, "bad number of max videocards specified\n"); |
---|
177 | return 1; |
---|
178 | } |
---|
179 | break; |
---|
180 | case 'd': |
---|
181 | debug_flag = 1; |
---|
182 | break; |
---|
183 | case 'p': |
---|
184 | recvPort = strtoul(optarg, 0, 0); |
---|
185 | break; |
---|
186 | |
---|
187 | case 'f': |
---|
188 | fileName = strdup(optarg); |
---|
189 | break; |
---|
190 | |
---|
191 | default: |
---|
192 | fprintf(stderr,"Don't know what option '%c'.\n", c); |
---|
193 | help(argv[0]); |
---|
194 | return 1; |
---|
195 | } |
---|
196 | } |
---|
197 | |
---|
198 | if (serverTable.numEntries == 0) { |
---|
199 | ERROR("no servers designated."); |
---|
200 | exit(0); |
---|
201 | } |
---|
202 | |
---|
203 | if (!ParseServersFile(fileName)) { |
---|
204 | exit(1); |
---|
205 | } |
---|
206 | |
---|
207 | // Bind this address to the socket. |
---|
208 | recvAddr.sin_family = AF_INET; |
---|
209 | recvAddr.sin_port = htons(recvPort); |
---|
210 | recvAddr.sin_addr.s_addr = htonl(INADDR_ANY); |
---|
211 | |
---|
212 | status = bind(sendFd, (struct sockaddr *)&recvAddr, sizeof(recvAddr)); |
---|
213 | if (status < 0) { |
---|
214 | ERROR("can't bind to address: ", strerror(errno)); |
---|
215 | exit(1); |
---|
216 | } |
---|
217 | |
---|
218 | if (!debug_flag) { |
---|
219 | if (daemon(0,1) < 0) { |
---|
220 | ERROR("can't daemonize nanoscale: ", strerror(errno)); |
---|
221 | exit(1); |
---|
222 | } |
---|
223 | } |
---|
224 | |
---|
225 | /* Build the array of servers listener file descriptors. */ |
---|
226 | FD_ZERO(&serverFds); |
---|
227 | for (hPtr = Tcl_FirstHashEntry(&serverTable, &iter); hPtr != NULL; |
---|
228 | hPtr = Tcl_NextHashEntry(&iter)) { |
---|
229 | RenderServer *serverPtr; |
---|
230 | |
---|
231 | serverPtr = Tcl_GetHashValue(hPtr); |
---|
232 | FD_SET(serverPtr->listenerFd, &serverFds); |
---|
233 | if (serverPtr->listenerFd > maxFd) { |
---|
234 | maxFs = serverPtr->listenerFd; |
---|
235 | } |
---|
236 | } |
---|
237 | while (select(maxFd+1, serverFds, NULL, NULL, 0) > 0) { |
---|
238 | |
---|
239 | for (hPtr = Tcl_FirstHashEntry(&serverTable, &iter); hPtr != NULL; |
---|
240 | hPtr = Tcl_NextHashEntry(&iter)) { |
---|
241 | RenderServer *serverPtr; |
---|
242 | |
---|
243 | serverPtr = Tcl_GetHashValue(hPtr); |
---|
244 | if (FD_ISSET(serverPtr->listenerFd, &serverFds)) { |
---|
245 | struct sockaddr_in newaddr; |
---|
246 | unsigned int addrlen; |
---|
247 | int f; |
---|
248 | int child; |
---|
249 | |
---|
250 | /* Accept the new connection. */ |
---|
251 | unsigned int addrlen = sizeof(newaddr); |
---|
252 | f = accept(serverPtr->listenerFd, (struct sockaddr *)&newaddr, |
---|
253 | sizeof(newaddr)); |
---|
254 | if (f < 0) { |
---|
255 | ERROR("can't accept server \"", serverPtr->name, |
---|
256 | "\": ", strerror(errno)); |
---|
257 | continue; |
---|
258 | } |
---|
259 | INFO("Connected to %s\n", inet_ntoa(newaddr.sin_addr)); |
---|
260 | |
---|
261 | dispNum++; |
---|
262 | if (dispNum >= maxCards) { |
---|
263 | dispNum = 0; |
---|
264 | } |
---|
265 | /* Fork the new process. Connect I/O to the new socket. */ |
---|
266 | child = fork(); |
---|
267 | if (child < 0) { |
---|
268 | ERROR("can't fork \"", serverPtr->name, "\": ", |
---|
269 | strerror(errno)); |
---|
270 | continue; |
---|
271 | } else if (child == 0) { |
---|
272 | int i; |
---|
273 | |
---|
274 | /* Child process. */ |
---|
275 | if (!debug_flag) { |
---|
276 | /* Disassociate server from */ |
---|
277 | status = daemon(0,1); |
---|
278 | if (status < 0) { |
---|
279 | ERROR("can't daemonize \"", serverPtr->name, |
---|
280 | "\": ", strerror(errno)); |
---|
281 | } |
---|
282 | } |
---|
283 | dup2(f, 0); /* Stdin */ |
---|
284 | dup2(f, 1); /* Stdout */ |
---|
285 | |
---|
286 | for(i = 3; i <= FD_SETSIZE; i++) { |
---|
287 | close(i); /* Close all the other descriptors. */ |
---|
288 | } |
---|
289 | if (maxCards > 1) { |
---|
290 | displayVar[11] = dispNum + '0'; |
---|
291 | } |
---|
292 | status = execvp(serverPtr->argv[0], serverPtr->argv); |
---|
293 | ERROR("can't execute \"", serverPtr->argv[0], |
---|
294 | "\": ", strerror(errno)); |
---|
295 | _exit(1); |
---|
296 | } |
---|
297 | _exit(EINVAL); |
---|
298 | } else { |
---|
299 | /* Reap initial child which will exit immediately |
---|
300 | * (grandchild continues) */ |
---|
301 | waitpid(status, NULL, 0); |
---|
302 | } |
---|
303 | } |
---|
304 | } |
---|
305 | } |
---|
306 | |
---|