xref: /plan9/sys/src/cmd/cwfs/pc.c (revision 8777f6886dbb72a923ec5e41671d53f78347b507)
1 #include "all.h"
2 #include "io.h"
3 
4 Mconf mconf;
5 
6 static void
mconfinit(void)7 mconfinit(void)
8 {
9 	int nf, pgsize = 0;
10 	ulong size, userpgs = 0, userused = 0;
11 	char *ln, *sl;
12 	char *fields[2];
13 	Biobuf *bp;
14 	Mbank *mbp;
15 
16 	size = 64*MB;
17 	bp = Bopen("#c/swap", OREAD);
18 	if (bp != nil) {
19 		while ((ln = Brdline(bp, '\n')) != nil) {
20 			ln[Blinelen(bp)-1] = '\0';
21 			nf = tokenize(ln, fields, nelem(fields));
22 			if (nf != 2)
23 				continue;
24 			if (strcmp(fields[1], "pagesize") == 0)
25 				pgsize = atoi(fields[0]);
26 			else if (strcmp(fields[1], "user") == 0) {
27 				sl = strchr(fields[0], '/');
28 				if (sl == nil)
29 					continue;
30 				userpgs = atol(sl+1);
31 				userused = atol(fields[0]);
32 			}
33 		}
34 		Bterm(bp);
35 		if (pgsize > 0 && userpgs > 0)
36 			size = (((userpgs - userused)*3LL)/4)*pgsize;
37 	}
38 	mconf.memsize = size;
39 	mbp = mconf.bank;
40 	mbp->base = 0x10000000;			/* fake addresses */
41 	mbp->limit = mbp->base + size;
42 	mbp++;
43 
44 	mconf.nbank = mbp - mconf.bank;
45 }
46 
47 ulong
meminit(void)48 meminit(void)
49 {
50 	conf.nmach = 1;
51 	mconfinit();
52 	return mconf.memsize;
53 }
54 
55 /*
56  * based on libthread's threadsetname, but drags in less library code.
57  * actually just sets the arguments displayed.
58  */
59 void
procsetname(char * fmt,...)60 procsetname(char *fmt, ...)
61 {
62 	int fd;
63 	char *cmdname;
64 	char buf[128];
65 	va_list arg;
66 
67 	va_start(arg, fmt);
68 	cmdname = vsmprint(fmt, arg);
69 	va_end(arg);
70 	if (cmdname == nil)
71 		return;
72 	snprint(buf, sizeof buf, "#p/%d/args", getpid());
73 	if((fd = open(buf, OWRITE)) >= 0){
74 		write(fd, cmdname, strlen(cmdname)+1);
75 		close(fd);
76 	}
77 	free(cmdname);
78 }
79 
80 void
newproc(void (* f)(void *),void * arg,char * text)81 newproc(void (*f)(void *), void *arg, char *text)
82 {
83 	int kid = rfork(RFPROC|RFMEM|RFNOWAIT);
84 
85 	if (kid < 0)
86 		sysfatal("can't fork: %r");
87 	if (kid == 0) {
88 		procsetname("%s", text);
89 		(*f)(arg);
90 		exits("child returned");
91 	}
92 }
93