Import sources from 2011-03-30 iso image

1 files changed, 142 insertions, 0 deletions

diff --git a/sys/src/libthread/note.c b/sys/src/libthread/note.c
new file mode 100755
index 000000000..74f7e9013
--- /dev/null
+++ b/sys/src/libthread/note.c
@@ -0,0 +1,142 @@
+#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;
+	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)
+					noted(NDFLT);
+				else if(strncmp(n->s, "sys:", 4)==0)
+					abort();
+				threadexitsall(n->s);
+			}
+			n->proc = nil;
+			unlock(&n->inuse);
+		}
+	}
+}
+
+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'\n", _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);
+}
+