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root/radiance/ray/src/util/netproc.c
Revision: 2.8
Committed: Tue Oct 28 14:01:39 1997 UTC (26 years, 5 months ago) by gregl
Content type: text/plain
Branch: MAIN
Changes since 2.7: +1 -21 lines
Log Message:
created selcall.h include file for select(2) compatibility

File Contents

# User Rev Content
1 greg 2.1 /* Copyright (c) 1996 Regents of the University of California */
2    
3     #ifndef lint
4     static char SCCSid[] = "$SunId$ LBL";
5     #endif
6    
7     /*
8     * Parallel network process handling routines
9     */
10    
11     #include <stdio.h>
12     #include <signal.h>
13     #include <fcntl.h>
14 gregl 2.8 #include "selcall.h"
15 greg 2.1 #include "netproc.h"
16 greg 2.5 #include "paths.h"
17 greg 2.1 #include "vfork.h"
18    
19     PSERVER *pslist = NULL; /* global process server list */
20    
21     static PROC *pindex[FD_SETSIZE]; /* process index table */
22    
23     static char ourhost[64]; /* this host name */
24 greg 2.5 static char ourdir[MAXPATH]; /* our working directory */
25 greg 2.1 static char ouruser[32]; /* our user name */
26     static char *ourshell; /* our user's shell */
27    
28     static fd_set errdesc; /* error file descriptors */
29     static int maxfd; /* maximum assigned descriptor */
30    
31 greg 2.3 extern char *remsh; /* externally defined remote shell program */
32    
33 greg 2.1 extern char *malloc(), *realloc();
34     extern char *getenv();
35    
36    
37     PSERVER *
38     addpserver(host, dir, usr, np) /* add a new process server */
39     char *host, *dir, *usr;
40     int np;
41     {
42     register PSERVER *ps;
43     /* allocate the struct */
44     if (np < 1)
45     return(NULL);
46     ps = (PSERVER *)malloc(sizeof(PSERVER)+(np-1)*sizeof(PROC));
47     if (ps == NULL)
48     return(NULL);
49     if (!ourhost[0]) { /* initialize */
50 greg 2.5 char dirtmp[MAXPATH];
51 greg 2.1 register char *cp;
52     register int len;
53    
54 greg 2.2 strcpy(ourhost, myhostname());
55 greg 2.4 getwd(dirtmp);
56 greg 2.1 if ((cp = getenv("HOME")) != NULL) {
57     if (!strcmp(cp, dirtmp))
58     ourdir[0] = '\0';
59     else if (!strncmp(cp, dirtmp, len=strlen(cp)) &&
60     dirtmp[len] == '/')
61     strcpy(ourdir, dirtmp+len+1);
62     else
63     strcpy(ourdir, dirtmp);
64     } else
65     strcpy(ourdir, dirtmp);
66     if ((cp = getenv("USER")) != NULL)
67     strcpy(ouruser, cp);
68     if ((ourshell = getenv("SHELL")) == NULL)
69     ourshell = "/bin/sh";
70     FD_ZERO(&errdesc);
71     maxfd = -1;
72     }
73     /* assign host, directory, user */
74     if (host == NULL || !strcmp(host, ourhost) ||
75     !strcmp(host, LHOSTNAME))
76     ps->hostname[0] = '\0';
77     else
78     strcpy(ps->hostname, host);
79     if (dir == NULL)
80     strcpy(ps->directory, ourdir);
81     else
82     strcpy(ps->directory, dir);
83     if (usr == NULL || !strcmp(usr, ouruser))
84     ps->username[0] = '\0';
85     else
86     strcpy(ps->username, usr);
87     /* clear process slots */
88     ps->nprocs = np;
89     while (np--) {
90     ps->proc[np].com = NULL;
91     ps->proc[np].pid = -1;
92     ps->proc[np].efd = -1;
93     ps->proc[np].errs = NULL;
94     ps->proc[np].elen = 0;
95     ps->proc[np].cf = NULL;
96     }
97     /* insert in our list */
98     ps->next = pslist;
99     pslist = ps;
100     /* check for signs of life */
101     if (!pserverOK(ps)) {
102     delpserver(ps); /* failure -- abort */
103     return(NULL);
104     }
105     return(ps);
106     }
107    
108    
109     delpserver(ps) /* delete a process server */
110     PSERVER *ps;
111     {
112     PSERVER pstart;
113     register PSERVER *psp;
114     register int i;
115     /* find server in our list */
116     pstart.next = pslist;
117     for (psp = &pstart; ps != psp->next; psp = psp->next)
118     if (psp->next == NULL)
119     return; /* not in our list! */
120     /* kill any running jobs */
121     for (i = 0; i < ps->nprocs; i++)
122     if (ps->proc[i].com != NULL) {
123     kill(SIGTERM, ps->proc[i].pid);
124     wait4job(ps, ps->proc[i].pid);
125     }
126     /* remove server from list */
127     psp->next = ps->next;
128     pslist = pstart.next;
129     free((char *)ps); /* free associated memory */
130     }
131    
132    
133     PSERVER *
134     findjob(pnp) /* find out where process is running */
135     register int *pnp; /* modified */
136     {
137     register PSERVER *ps;
138     register int i;
139    
140     for (ps = pslist; ps != NULL; ps = ps->next)
141     for (i = 0; i < ps->nprocs; i++)
142     if (ps->proc[i].pid == *pnp) {
143     *pnp = i;
144     return(ps);
145     }
146     return(NULL); /* not found */
147     }
148    
149    
150     int
151     startjob(ps, command, compf) /* start a job on a process server */
152     register PSERVER *ps;
153     char *command;
154     int (*compf)();
155     {
156 greg 2.5 char udirt[MAXPATH];
157 greg 2.3 char *av[16];
158 greg 2.1 int pfd[2], pid;
159     register int i;
160    
161     if (ps == NULL) { /* find a server */
162     for (ps = pslist; ps != NULL; ps = ps->next)
163     if ((i = startjob(ps, command, compf)) != -1)
164     return(i); /* got one */
165     return(-1); /* no slots anywhere */
166     }
167     for (i = 0; i < ps->nprocs; i++)
168     if (ps->proc[i].com == NULL)
169     break;
170     if (i >= ps->nprocs)
171     return(-1); /* out of process slots */
172     /* open pipe */
173     if (pipe(pfd) < 0) {
174     perror("cannot open pipe");
175     exit(1);
176     }
177     /* start child process */
178     if ((pid = vfork()) == 0) {
179     close(pfd[0]); /* connect stderr to pipe */
180     if (pfd[1] != 2) {
181     dup2(pfd[1], 2);
182     close(pfd[1]);
183     }
184     if (ps->hostname[0]) { /* rsh command */
185 greg 2.3 av[i=0] = remsh;
186 greg 2.1 av[++i] = ps->hostname;
187 greg 2.3 av[++i] = "-n"; /* no stdin */
188     if (ps->username[0]) { /* different user */
189 greg 2.1 av[++i] = "-l";
190     av[++i] = ps->username;
191 greg 2.3 av[++i] = "cd";
192     udirt[0] = '~';
193     strcpy(udirt+1, ouruser);
194     av[++i] = udirt;
195     av[++i] = ";";
196 greg 2.1 }
197 greg 2.3 if (ps->directory[0]) { /* change directory */
198 greg 2.1 av[++i] = "cd";
199     av[++i] = ps->directory;
200     av[++i] = ";";
201     }
202     av[++i] = command;
203     av[++i] = NULL;
204     } else { /* shell command */
205     av[0] = ourshell;
206     av[1] = "-c";
207     av[2] = command;
208     av[3] = NULL;
209     }
210     execv(av[0], av);
211     _exit(1);
212     }
213     if (pid == -1) {
214     perror("fork failed");
215     exit(1);
216     }
217     ps->proc[i].com = command; /* assign process slot */
218     ps->proc[i].cf = compf;
219     ps->proc[i].pid = pid;
220     close(pfd[1]); /* get piped stderr file descriptor */
221     ps->proc[i].efd = pfd[0];
222     fcntl(pfd[0], F_SETFD, 1); /* set close on exec flag */
223     pindex[pfd[0]] = ps->proc + i; /* assign error fd index */
224     FD_SET(pfd[0], &errdesc); /* add to select call parameter */
225     if (pfd[0] > maxfd)
226     maxfd = pfd[0];
227     return(pid); /* return to parent process */
228     }
229    
230    
231     static int
232     readerrs(fd) /* read error output from fd */
233     int fd;
234     {
235     char errbuf[BUFSIZ];
236     int nr;
237     register PROC *pp;
238     /* look up associated process */
239     if ((pp = pindex[fd]) == NULL)
240     abort(); /* serious consistency error */
241     nr = read(fd, errbuf, BUFSIZ-1);
242     if (nr < 0) {
243     perror("read error");
244     exit(1);
245     }
246     if (nr == 0) /* stream closed (process finished) */
247     return(0);
248     errbuf[nr] = '\0'; /* add to error buffer */
249     if (pp->elen == 0)
250     pp->errs = (char *)malloc(nr+1);
251     else
252     pp->errs = (char *)realloc(pp->errs, pp->elen+nr+1);
253     if (pp->errs == NULL) {
254     perror("malloc failed");
255     exit(1);
256     }
257     strcpy(pp->errs+pp->elen, errbuf);
258     pp->elen += nr;
259     return(nr);
260     }
261    
262    
263     static
264     wait4end() /* read error streams until someone is done */
265     {
266     fd_set readfds, excepfds;
267     register int i;
268     /* find end of descriptor set */
269     for ( ; maxfd >= 0; maxfd--)
270     if (FD_ISSET(maxfd, &errdesc))
271     break;
272     if (maxfd < 0)
273     return; /* nothing to read */
274     readfds = excepfds = errdesc;
275     while (select(maxfd+1, &readfds, NULL, &excepfds, NULL) > 0)
276     for (i = 0; i <= maxfd; i++) /* get pending i/o */
277     if (FD_ISSET(i, &readfds) || FD_ISSET(i, &excepfds))
278     if (readerrs(i) == 0)
279     return; /* finished process */
280     perror("select call failed");
281     exit(1);
282     }
283    
284    
285     static int
286     finishjob(ps, pn, status) /* clean up finished process */
287     PSERVER *ps;
288     int pn;
289     int status;
290     {
291     register PROC *pp;
292    
293     pp = ps->proc + pn;
294     if (pp->cf != NULL) /* client cleanup */
295     status = (*pp->cf)(ps, pn, status);
296     close(pp->efd); /* close error stream */
297     pindex[pp->efd] = NULL;
298     FD_CLR(pp->efd, &errdesc);
299     free((char *)pp->errs);
300     pp->com = NULL; /* clear settings */
301     pp->pid = -1;
302     pp->efd = -1;
303     pp->errs = NULL;
304     pp->elen = 0;
305     pp->cf = NULL;
306     return(status);
307     }
308    
309    
310     int
311     wait4job(ps, pid) /* wait for process to finish */
312     PSERVER *ps;
313     int pid;
314     {
315     int status, psn, psn2;
316     PSERVER *ps2;
317    
318     if (pid == -1) { /* wait for first job */
319     if (ps != NULL) {
320     for (psn = ps->nprocs; psn--; )
321     if (ps->proc[psn].com != NULL)
322     break;
323     if (psn < 0)
324     return(-1); /* no processes this server */
325     }
326     do {
327     wait4end(); /* wait for something to end */
328     if ((psn2 = wait(&status)) == -1)
329     return(-1); /* none left */
330     ps2 = findjob(&psn2);
331     if (ps2 != NULL) /* clean up job if ours */
332     status = finishjob(ps2, psn2, status);
333     } while (ps2 == NULL || (ps != NULL && ps2 != ps));
334     return(status); /* return job status */
335     }
336     psn = pid; /* else find specific job */
337     ps2 = findjob(&psn); /* find process slot */
338     if (ps2 == NULL || (ps != NULL && ps2 != ps))
339     return(-1); /* inconsistent target */
340     ps = ps2;
341     do {
342     wait4end(); /* wait for something to end */
343     if ((psn2 = wait(&status)) == -1)
344     return(-1); /* none left */
345     ps2 = findjob(&psn2);
346     if (ps2 != NULL) /* clean up job if ours */
347     status = finishjob(ps2, psn2, status);
348     } while (ps2 != ps || psn2 != psn);
349     return(status); /* return job status */
350     }