1990/0227/port/pgrp.c (diff list | history)

port/pgrp.c on 1990/0227
1990/0227		#include "u.h" #include "lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "errno.h" struct{ Lock; Pgrp *free; ulong pgrpid; }pgrpalloc; struct{ Lock; Mount *free; ulong mountid; }mountalloc; void pgrpinit(void) { int i; Pgrp *p; Mount *m; pgrpalloc.free = ialloc(conf.npgrp*sizeof(Pgrp), 0); p = pgrpalloc.free; for(i=0; i<conf.npgrp-1; i++,p++){ p->next = p+1; p->mtab = ialloc(conf.nmtab*sizeof(Mtab), 0); p->etab = ialloc(conf.npgenv*sizeof(Envp*), 0); } p->next = 0; mountalloc.free = ialloc(conf.nmount*sizeof(Mount), 0); m = mountalloc.free; for(i=0; i<conf.nmount-1; i++,m++) m->next = m+1; m->next = 0; } Pgrp* newpgrp(void) { Pgrp *p; loop: lock(&pgrpalloc); if(p = pgrpalloc.free){ /* assign = */ pgrpalloc.free = p->next; p->ref = 1; p->pgrpid = ++pgrpalloc.pgrpid; p->nmtab = 0; p->nenv = 0; unlock(&pgrpalloc); return p; } unlock(&pgrpalloc); print("no pgrps\n"); if(u == 0) panic("newpgrp"); u->p->state = Wakeme; alarm(1000, wakeme, u->p); sched(); goto loop; } void closepgrp(Pgrp *p) { int i; Mtab *m; Envp *ep; if(decref(p) == 0){ m = p->mtab; for(i=0; i<p->nmtab; i++,m++) if(m->c){ close(m->c); closemount(m->mnt); } ep = p->etab; for(i=0; i<p->nenv; i++,ep++) if(ep->env) envpgclose(ep->env); lock(&pgrpalloc); p->next = pgrpalloc.free; pgrpalloc.free = p; unlock(&pgrpalloc); } } Mount* newmount(void) { Mount *m; loop: lock(&mountalloc); if(m = mountalloc.free){ /* assign = */ mountalloc.free = m->next; m->ref = 1; m->mountid = ++mountalloc.mountid; unlock(&mountalloc); return m; } unlock(&mountalloc); print("no mounts\n"); if(u == 0) panic("newmount"); u->p->state = Wakeme; alarm(1000, wakeme, u->p); sched(); goto loop; } void closemount(Mount *m) { lock(m); if(m->ref == 1){ close(m->c); if(m->next) closemount(m->next); unlock(m); lock(&mountalloc); m->mountid = 0; m->next = mountalloc.free; mountalloc.free = m; unlock(&mountalloc); return; } m->ref--; unlock(m); } void pgrpcpy(Pgrp *to, Pgrp *from) { int i; Mtab *m; Envp *ep; Env *e; lock(from); memcpy(to->user, from->user, NAMELEN); memcpy(to->mtab, from->mtab, from->nmtab*sizeof(Mtab)); to->nmtab = from->nmtab; m = to->mtab; for(i=0; i<from->nmtab; i++,m++) if(m->c){ incref(m->c); lock(m->mnt); m->mnt->ref++; unlock(m->mnt); } to->nenv = from->nenv; ep = to->etab; for(i=0; i<from->nenv; i++,ep++){ ep->chref = 0; e = ep->env = from->etab[i].env; if(e){ lock(e); if(waserror()){ unlock(e); unlock(from); ep->env = 0; nexterror(); } /* * If pgrp being forked has an open channel * on this env, it may write it after the fork * so make a copy now. * Don't worry about other pgrps, because they * will copy if they are about to write. */ if(from->etab[i].chref){ ep->env = copyenv(e, 0); unlock(ep->env); }else e->pgref++; poperror(); unlock(e); } } unlock(from); }