a

kern/pgrp.c

@@ -0,0 +1,272 @@
+#include	"u.h"
+#include	"lib.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"error.h"
+
+static Ref pgrpid;
+static Ref mountid;
+
+#ifdef NOTDEF
+void
+pgrpnote(ulong noteid, char *a, long n, int flag)
+{
+	Proc *p, *ep;
+	char buf[ERRMAX];
+
+	if(n >= ERRMAX-1)
+		error(Etoobig);
+
+	memmove(buf, a, n);
+	buf[n] = 0;
+	p = proctab(0);
+	ep = p+conf.nproc;
+	for(; p < ep; p++) {
+		if(p->state == Dead)
+			continue;
+		if(up != p && p->noteid == noteid && p->kp == 0) {
+			qlock(&p->debug);
+			if(p->pid == 0 || p->noteid != noteid){
+				qunlock(&p->debug);
+				continue;
+			}
+			if(!waserror()) {
+				postnote(p, 0, buf, flag);
+				poperror();
+			}
+			qunlock(&p->debug);
+		}
+	}
+}
+#endif
+
+Pgrp*
+newpgrp(void)
+{
+	Pgrp *p;
+
+	p = smalloc(sizeof(Pgrp));
+	p->ref.ref = 1;
+	p->pgrpid = incref(&pgrpid);
+	return p;
+}
+
+Rgrp*
+newrgrp(void)
+{
+	Rgrp *r;
+
+	r = smalloc(sizeof(Rgrp));
+	r->ref.ref = 1;
+	return r;
+}
+
+void
+closergrp(Rgrp *r)
+{
+	if(decref(&r->ref) == 0)
+		free(r);
+}
+
+void
+closepgrp(Pgrp *p)
+{
+	Mhead **h, **e, *f, *next;
+
+	if(decref(&p->ref) != 0)
+		return;
+
+	qlock(&p->debug);
+	wlock(&p->ns);
+	p->pgrpid = -1;
+
+	e = &p->mnthash[MNTHASH];
+	for(h = p->mnthash; h < e; h++) {
+		for(f = *h; f; f = next) {
+			wlock(&f->lock);
+			cclose(f->from);
+			mountfree(f->mount);
+			f->mount = nil;
+			next = f->hash;
+			wunlock(&f->lock);
+			putmhead(f);
+		}
+	}
+	wunlock(&p->ns);
+	qunlock(&p->debug);
+	free(p);
+}
+
+void
+pgrpinsert(Mount **order, Mount *m)
+{
+	Mount *f;
+
+	m->order = 0;
+	if(*order == 0) {
+		*order = m;
+		return;
+	}
+	for(f = *order; f; f = f->order) {
+		if(m->mountid < f->mountid) {
+			m->order = f;
+			*order = m;
+			return;
+		}
+		order = &f->order;
+	}
+	*order = m;
+}
+
+/*
+ * pgrpcpy MUST preserve the mountid allocation order of the parent group
+ */
+void
+pgrpcpy(Pgrp *to, Pgrp *from)
+{
+	int i;
+	Mount *n, *m, **link, *order;
+	Mhead *f, **tom, **l, *mh;
+
+	wlock(&from->ns);
+	order = 0;
+	tom = to->mnthash;
+	for(i = 0; i < MNTHASH; i++) {
+		l = tom++;
+		for(f = from->mnthash[i]; f; f = f->hash) {
+			rlock(&f->lock);
+			mh = newmhead(f->from);
+			*l = mh;
+			l = &mh->hash;
+			link = &mh->mount;
+			for(m = f->mount; m; m = m->next) {
+				n = newmount(mh, m->to, m->mflag, m->spec);
+				m->copy = n;
+				pgrpinsert(&order, m);
+				*link = n;
+				link = &n->next;
+			}
+			runlock(&f->lock);
+		}
+	}
+	/*
+	 * Allocate mount ids in the same sequence as the parent group
+	 */
+	lock(&mountid.lk);
+	for(m = order; m; m = m->order)
+		m->copy->mountid = mountid.ref++;
+	unlock(&mountid.lk);
+	wunlock(&from->ns);
+}
+
+Fgrp*
+dupfgrp(Fgrp *f)
+{
+	Fgrp *new;
+	Chan *c;
+	int i;
+
+	new = smalloc(sizeof(Fgrp));
+	if(f == nil){
+		new->fd = smalloc(DELTAFD*sizeof(Chan*));
+		new->nfd = DELTAFD;
+		new->ref.ref = 1;
+		return new;
+	}
+
+	lock(&f->ref.lk);
+	/* Make new fd list shorter if possible, preserving quantization */
+	new->nfd = f->maxfd+1;
+	i = new->nfd%DELTAFD;
+	if(i != 0)
+		new->nfd += DELTAFD - i;
+	new->fd = malloc(new->nfd*sizeof(Chan*));
+	if(new->fd == 0){
+		unlock(&f->ref.lk);
+		error("no memory for fgrp");
+	}
+	new->ref.ref = 1;
+
+	new->maxfd = f->maxfd;
+	for(i = 0; i <= f->maxfd; i++) {
+		if(c = f->fd[i]){
+			incref(&c->ref);
+			new->fd[i] = c;
+		}
+	}
+	unlock(&f->ref.lk);
+
+	return new;
+}
+
+void
+closefgrp(Fgrp *f)
+{
+	int i;
+	Chan *c;
+
+	if(f == 0)
+		return;
+
+	if(decref(&f->ref) != 0)
+		return;
+
+	for(i = 0; i <= f->maxfd; i++)
+		if(c = f->fd[i])
+			cclose(c);
+
+	free(f->fd);
+	free(f);
+}
+
+Mount*
+newmount(Mhead *mh, Chan *to, int flag, char *spec)
+{
+	Mount *m;
+
+	m = smalloc(sizeof(Mount));
+	m->to = to;
+	m->head = mh;
+	incref(&to->ref);
+	m->mountid = incref(&mountid);
+	m->mflag = flag;
+	if(spec != 0)
+		kstrdup(&m->spec, spec);
+
+	return m;
+}
+
+void
+mountfree(Mount *m)
+{
+	Mount *f;
+
+	while(m) {
+		f = m->next;
+		cclose(m->to);
+		m->mountid = 0;
+		free(m->spec);
+		free(m);
+		m = f;
+	}
+}
+
+#ifdef NOTDEF
+void
+resrcwait(char *reason)
+{
+	char *p;
+
+	if(up == 0)
+		panic("resrcwait");
+
+	p = up->psstate;
+	if(reason) {
+		up->psstate = reason;
+		print("%s\n", reason);
+	}
+
+	tsleep(&up->sleep, return0, 0, 300);
+	up->psstate = p;
+}
+#endif