1 #include <u.h>
2 #include <libc.h>
3 #include "9proc.h"
4 
5 static Lock uproclock;
6 static Uproc *phash[PIDHASH];
7 
8 Uproc*
9 _p9uproc(void)
10 {
11 	/* for now, assume getpid is fast or cached */
12 	int pid;
13 	Uproc *up;
14 
15 	pid = getpid();
16 again:
17 if(0)print("find %d\n", pid);
18 	lock(&uproclock);
19 	for(up=phash[pid%PIDHASH]; up; up=up->next){
20 		if(up->pid == pid){
21 if(0)print("found %d\n", pid);
22 			unlock(&uproclock);
23 			return up;
24 		}
25 	}
26 
27 	up = mallocz(sizeof(Uproc), 1);
28 	if(up == nil){
29 if(0)print("again %d\n", pid);
30 		unlock(&uproclock);
31 		sleep(1000);
32 		goto again;
33 	}
34 
35 againpipe:
36 	if(pipe(up->pipe) < 0){
37 if(0)print("againpipe %d\n", pid);
38 		sleep(1000);
39 		goto againpipe;
40 	}
41 
42 	up->pid = pid;
43 	up->next = phash[pid%PIDHASH];
44 	phash[pid%PIDHASH] = up;
45 if(0)print("link %d\n", pid);
46 	unlock(&uproclock);
47 	return up;
48 }
49 
50 void
51 _p9uprocdie(void)
52 {
53 	Uproc **l, *up;
54 	int pid;
55 
56 	pid = getpid();
57 if(0)print("die %d\n", pid);
58 	lock(&uproclock);
59 	for(l=&phash[pid%33]; *l; l=&(*l)->next){
60 		if((*l)->pid == pid){
61 			up = *l;
62 			*l = up->next;
63 if(0)print("died %d\n", pid);
64 			unlock(&uproclock);
65 			close(up->pipe[0]);
66 			close(up->pipe[1]);
67 			free(up);
68 			return;
69 		}
70 	}
71 if(0)print("not started %d\n", pid);
72 	unlock(&uproclock);
73 }