ref: 440ccbc06007422f04943378260f250f9efa5331
dir: /sys/src/libthread/note.c/
#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; } lock(&onnotelock); for(i=0; i<NFN; i++) if(onnote[i]==from){ onnote[i] = to; onnotepid[i] = topid; break; } unlock(&onnotelock); return i<NFN; } static void delayednotes(Proc *p, void *v) { int i; Note *n; char s[ERRMAX]; int (*fn)(void*, char*); if(!p->pending) return; p->pending = 0; for(n=notes; n<enotes; n++){ if(n->proc == p){ strcpy(s, n->s); n->proc = nil; unlock(&n->inuse); for(i=0; i<NFN; i++){ if(onnotepid[i]!=p->pid || (fn = onnote[i])==nil) continue; if((*fn)(v, s)) break; } if(i==NFN){ _threaddebug(DBGNOTE, "Unhandled note %s, proc %p", n->s, p); if(v != nil) noted(NDFLT); else if(strncmp(n->s, "sys:", 4)==0) abort(); threadexitsall(n->s); } } } } void _threadnote(void *v, char *s) { Proc *p; Note *n; _threaddebug(DBGNOTE, "Got note %s", s); if(strncmp(s, "sys:", 4) == 0) noted(NDFLT); if(_threadexitsallstatus){ _threaddebug(DBGNOTE, "Threadexitsallstatus = '%s'", _threadexitsallstatus); _exits(_threadexitsallstatus); } if(strcmp(s, "threadint")==0) noted(NCONT); p = _threadgetproc(); if(p == nil) noted(NDFLT); for(n=notes; n<enotes; n++) if(canlock(&n->inuse)) break; if(n==enotes) sysfatal("libthread: too many delayed notes"); utfecpy(n->s, n->s+ERRMAX, s); n->proc = p; p->pending = 1; if(!p->splhi) delayednotes(p, v); 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); }