ref: dfec09c436a8a328fc97007cf2dc3cd5476cc748
dir: /sys/src/9/ip/loopbackmedium.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "ip.h" enum { Maxtu= 16*1024, }; typedef struct LB LB; struct LB { Proc *readp; Queue *q; Fs *f; }; static void loopbackread(void *a); static void loopbackbind(Ipifc *ifc, int, char**) { LB *lb; lb = smalloc(sizeof(*lb)); lb->f = ifc->conv->p->f; lb->q = qopen(1024*1024, Qmsg, nil, nil); ifc->arg = lb; kproc("loopbackread", loopbackread, ifc); } static void loopbackunbind(Ipifc *ifc) { LB *lb = ifc->arg; if(lb->readp) postnote(lb->readp, 1, "unbind", 0); /* wait for reader to die */ while(lb->readp != 0) tsleep(&up->sleep, return0, 0, 300); /* clean up */ qfree(lb->q); free(lb); } static void loopbackbwrite(Ipifc *ifc, Block *bp, int, uchar*) { LB *lb; lb = ifc->arg; if(qpass(lb->q, bp) < 0) ifc->outerr++; ifc->out++; } static void loopbackread(void *a) { Ipifc *ifc; Block *bp; LB *lb; ifc = a; lb = ifc->arg; lb->readp = up; /* hide identity under a rock for unbind */ if(waserror()){ lb->readp = nil; pexit("hangup", 1); } for(;;){ bp = qbread(lb->q, Maxtu); if(bp == nil) continue; if(!canrlock(ifc)){ freeb(bp); continue; } if(waserror()){ runlock(ifc); nexterror(); } ifc->in++; if(ifc->lifc == nil) freeb(bp); else ipiput4(lb->f, ifc, bp); runlock(ifc); poperror(); } } Medium loopbackmedium = { .hsize= 0, .mintu= 0, .maxtu= Maxtu, .maclen= 0, .name= "loopback", .bind= loopbackbind, .unbind= loopbackunbind, .bwrite= loopbackbwrite, }; void loopbackmediumlink(void) { addipmedium(&loopbackmedium); }