jehanne/sys/src/lib/thread/note.c

152 lines
2.7 KiB
C

/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <libc.h>
#include <thread.h>
#include "threadimpl.h"
int _threadnopasser;
#define NFN 33
#define ERRLEN 48
typedef struct Note Note;
struct Note
{
Lock inuse;
Proc *proc; /* recipient */
char s[ERRMAX]; /* arg2 */
};
static Note notes[128];
static Note *enotes = notes+nelem(notes);
static int (*onnote[NFN])(void*, char*);
static int onnotepid[NFN];
static Lock onnotelock;
int
threadnotify(int (*f)(void*, char*), int in)
{
int i, topid;
int (*from)(void*, char*), (*to)(void*, char*);
if(in){
from = nil;
to = f;
topid = _threadgetproc()->pid;
}else{
from = f;
to = nil;
topid = 0;
}
jehanne_lock(&onnotelock);
for(i=0; i<NFN; i++)
if(onnote[i]==from){
onnote[i] = to;
onnotepid[i] = topid;
break;
}
jehanne_unlock(&onnotelock);
return i<NFN;
}
static void
delayednotes(Proc *p, void *v)
{
int i;
Note *n;
int (*fn)(void*, char*);
if(!p->pending)
return;
p->pending = 0;
for(n=notes; n<enotes; n++){
if(n->proc == p){
for(i=0; i<NFN; i++){
if(onnotepid[i]!=p->pid || (fn = onnote[i])==nil)
continue;
if((*fn)(v, n->s))
break;
}
if(i==NFN){
_threaddebug(DBGNOTE, "Unhandled note %s, proc %p\n", n->s, p);
if(v != nil)
sys_noted(NDFLT);
else if(jehanne_strncmp(n->s, "sys:", 4)==0)
abort();
threadexitsall(n->s);
}
n->proc = nil;
jehanne_unlock(&n->inuse);
}
}
}
void
_threadnote(void *v, char *s)
{
Proc *p;
Note *n;
_threaddebug(DBGNOTE, "Got note %s", s);
if(jehanne_strncmp(s, "sys:", 4) == 0)
sys_noted(NDFLT);
if(_threadexitsallstatus){
_threaddebug(DBGNOTE, "Threadexitsallstatus = '%s'\n", _threadexitsallstatus);
sys__exits(_threadexitsallstatus);
}
if(jehanne_strcmp(s, "threadint")==0)
sys_noted(NCONT);
p = _threadgetproc();
if(p == nil)
sys_noted(NDFLT);
for(n=notes; n<enotes; n++)
if(jehanne_canlock(&n->inuse))
break;
if(n==enotes)
jehanne_sysfatal("libthread: too many delayed notes");
jehanne_utfecpy(n->s, n->s+ERRMAX, s);
n->proc = p;
p->pending = 1;
if(!p->splhi)
delayednotes(p, v);
sys_noted(NCONT);
}
int
_procsplhi(void)
{
int s;
Proc *p;
p = _threadgetproc();
s = p->splhi;
p->splhi = 1;
return s;
}
void
_procsplx(int s)
{
Proc *p;
p = _threadgetproc();
p->splhi = s;
if(s)
return;
if(p->pending)
delayednotes(p, nil);
}