1991/0501/port/sysfile.c (diff list | history)

port/sysfile.c on 1990/0227
1990/0227		#include "u.h" #include "lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "errno.h" #include "fcall.h" /* * The sys*() routines needn't poperror() as they return directly to syscall(). */ int newfd(void) { int i; for(i=0; i<NFD; i++) if(u->fd[i] == 0){ if(i > u->maxfd) u->maxfd = i; return i; }
1990/11211		error(Enofd);
1990/0227		} Chan* fdtochan(int fd, int mode) { Chan *c;
1990/1210		c = 0; /* set */
1990/0227		if(fd<0 || NFD<=fd || (c=u->fd[fd])==0)
1990/11211		error(Ebadfd);
1990/1009		if(mode<0 || c->mode==ORDWR)
1990/0227		return c;
1990/1009		if((mode&OTRUNC) && c->mode==OREAD)
1990/0227		err:
1990/11211		error(Ebadusefd);
1990/1009		if((mode&~OTRUNC) != c->mode)
1990/0227		goto err; return c; } int openmode(ulong o) {
1990/08141		if(o >= (OTRUNC|OCEXEC|ORCLOSE|OEXEC))
1990/0227		Err:
1990/11211		error(Ebadarg);
1990/08141		o &= ~(OTRUNC|OCEXEC|ORCLOSE);
1990/0227		if(o > OEXEC) goto Err; if(o == OEXEC) return OREAD; return o; } long
1990/1009		syspipe(ulong *arg) { int fd[2]; Chan *c[2]; Dev *d; validaddr(arg[0], 2*BY2WD, 1); evenaddr(arg[0]); d = &devtab[devno('|', 0)]; c[0] = (*d->attach)(0); c[1] = 0; fd[0] = -1; fd[1] = -1; if(waserror()){ close(c[0]); if(c[1]) close(c[1]); if(fd[0] >= 0) u->fd[fd[0]]=0; if(fd[1] >= 0) u->fd[fd[1]]=0; nexterror(); } c[1] = (*d->clone)(c[0], 0); (*d->walk)(c[0], "data"); (*d->walk)(c[1], "data1"); c[0] = (*d->open)(c[0], ORDWR); c[1] = (*d->open)(c[1], ORDWR); fd[0] = newfd(); u->fd[fd[0]] = c[0]; fd[1] = newfd(); u->fd[fd[1]] = c[1]; ((long*)arg[0])[0] = fd[0]; ((long*)arg[0])[1] = fd[1]; poperror(); return 0; } long
1990/0227		sysdup(ulong *arg) { int fd; Chan *c, *oc; /* * Close after dup'ing, so date > #d/1 works */ c = fdtochan(arg[0], -1); fd = arg[1];
1991/0221		if(fd != -1){ if(fd<0 || NFD<=fd) error(Ebadfd); if(fd > u->maxfd) u->maxfd = fd;
1990/0227		oc = u->fd[fd];
1991/0221		}else{
1990/0227		oc = 0; fd = newfd(); } u->fd[fd] = c; incref(c); if(oc) close(oc); return fd; } long sysopen(ulong *arg) { int fd; Chan *c; openmode(arg[1]); /* error check only */ fd = newfd(); validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Aopen, arg[1], 0); u->fd[fd] = c; return fd; } void fdclose(int fd) { int i; u->fd[fd] = 0; if(fd == u->maxfd) for(i=fd; --i>=0 && u->fd[i]==0; ) u->maxfd = i; } long sysclose(ulong *arg) { Chan *c; c = fdtochan(arg[0], -1); close(c); fdclose(arg[0]); return 0; } long unionread(Chan *c, void *va, long n) { Mount *mnt; Chan *mc, *nc; Pgrp *pg = u->p->pgrp; long nr; mnt = c->mnt; lock(pg); if(c->mountid != mnt->mountid){
1990/0321		pprint("unionread: changed underfoot?\n");
1990/0227		unlock(pg); return 0; } Again: mc = mnt->c; incref(mc); unlock(pg); if(waserror()){ close(mc); nexterror(); } nc = clone(mc, 0); close(mc); poperror(); if(waserror()){ close(nc); nexterror(); } nc = (*devtab[nc->type].open)(nc, OREAD); nc->offset = c->offset;
1991/0411		nr = (*devtab[nc->type].read)(nc, va, n, nc->offset);
1990/0821		c->offset = nc->offset; /* devdirread e.g. changes it */
1990/0227		close(nc); poperror(); if(nr > 0) return nr; /* * Advance to next element */ lock(pg); mnt = c->mnt; if(c->mountid != mnt->mountid){ print("unionread: changed underfoot?\n"); unlock(pg); return 0; } if(mnt->term){ unlock(pg); return 0; } mnt = mnt->next; c->mnt = mnt; c->mountid = mnt->mountid; c->offset = 0; goto Again; } long sysread(ulong *arg) { Chan *c; long n;
1990/1009		c = fdtochan(arg[0], OREAD);
1990/1004		validaddr(arg[1], arg[2], 1);
1991/0411		qlock(&c->rdl);
1991/0501
1990/0227		if(waserror()){
1991/0411		qunlock(&c->rdl);
1990/0227		nexterror(); } n = arg[2];
1990/11211		if(c->qid.path & CHDIR){
1990/0227		n -= n%DIRLEN; if(c->offset%DIRLEN || n==0)
1990/11211		error(Ebaddirread);
1990/0227		}
1990/11211		if((c->qid.path&CHDIR) && (c->flag&CMOUNT))
1990/0227		n = unionread(c, (void*)arg[1], n); else
1991/0411		n = (*devtab[c->type].read)(c, (void*)arg[1], n, c->offset);
1990/0227		c->offset += n;
1991/0411		qunlock(&c->rdl);
1990/0227		return n; } long syswrite(ulong *arg) { Chan *c; long n;
1990/1009		c = fdtochan(arg[0], OWRITE);
1990/0227		validaddr(arg[1], arg[2], 0);
1991/0411		qlock(&c->wrl);
1991/0501
1990/0227		if(waserror()){
1991/0411		qunlock(&c->wrl);
1990/0227		nexterror(); }
1990/11211		if(c->qid.path & CHDIR) error(Eisdir);
1991/0411		n = (*devtab[c->type].write)(c, (void*)arg[1], arg[2], c->offset);
1990/0227		c->offset += n;
1991/0411		qunlock(&c->wrl);
1990/0227		return n; } long sysseek(ulong *arg) { Chan *c; char buf[DIRLEN]; Dir dir; long off; c = fdtochan(arg[0], -1);
1990/11211		if(c->qid.path & CHDIR) error(Eisdir);
1991/0319		if(devchar[c->type] == '|') error(Eisstream);
1991/0411		qlock(&c->rdl); qlock(&c->wrl);
1990/0227		if(waserror()){
1991/0411		qunlock(&c->rdl); qunlock(&c->wrl);
1990/0227		nexterror(); } switch(arg[2]){ case 0: c->offset = arg[1]; break; case 1: c->offset += (long)arg[1]; break; case 2: (*devtab[c->type].stat)(c, buf); convM2D(buf, &dir); c->offset = dir.length + (long)arg[1]; break; } off = c->offset;
1991/0411		qunlock(&c->rdl); qunlock(&c->wrl);
1990/0227		poperror(); return off; } long sysfstat(ulong *arg) { Chan *c; long n; validaddr(arg[1], DIRLEN, 1); evenaddr(arg[1]); c = fdtochan(arg[0], -1); (*devtab[c->type].stat)(c, (char*)arg[1]); return 0; } long sysstat(ulong *arg) { Chan *c; long n; validaddr(arg[1], DIRLEN, 1); evenaddr(arg[1]); validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Aaccess, 0, 0); if(waserror()){ close(c); nexterror(); } (*devtab[c->type].stat)(c, (char*)arg[1]); poperror(); close(c); return 0; } long syschdir(ulong *arg) { Chan *c; validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Atodir, 0, 0); close(u->dot); u->dot = c; return 0; } long bindmount(ulong *arg, int ismount) { Chan *c0, *c1; ulong flag; long ret;
1990/0918		char *p; int t;
1990/0227		struct{ Chan *chan; char *spec;
1990/11211		char *auth;
1990/0227		}bogus; flag = arg[2]; if(flag>MMASK || (flag&MORDER)==(MBEFORE|MAFTER))
1990/11211		error(Ebadarg);
1990/0227		if(ismount){ bogus.chan = fdtochan(arg[0], 2);
1990/11211		validaddr(arg[3], 1, 0);
1990/0918		p = (char*)arg[3]; t = BY2PG-((ulong)p&(BY2PG-1)); while(vmemchr(p, 0, t) == 0){ p += t; t = BY2PG; }
1990/0227		bogus.spec = (char*)arg[3];
1990/11211		validaddr(arg[4], 1, 0); p = (char*)arg[4]; t = BY2PG-((ulong)p&(BY2PG-1)); while(vmemchr(p, 0, t) == 0){ p += t; t = BY2PG; } bogus.auth = (char*)arg[4];
1990/0227		ret = devno('M', 0); c0 = (*devtab[ret].attach)((char*)&bogus); }else{ validaddr(arg[0], 1, 0); c0 = namec((char*)arg[0], Aaccess, 0, 0); } if(waserror()){ close(c0); nexterror(); } validaddr(arg[1], 1, 0); c1 = namec((char*)arg[1], Amount, 0, 0); if(waserror()){ close(c1); nexterror(); }
1990/11211		if((c0->qid.path^c1->qid.path) & CHDIR) error(Ebadmount); if(flag && !(c0->qid.path&CHDIR)) error(Ebadmount);
1990/0227		ret = mount(c0, c1, flag); close(c0); close(c1); if(ismount){ close(bogus.chan); fdclose(arg[0]); } return ret; } long sysbind(ulong *arg) { return bindmount(arg, 0); } long sysmount(ulong *arg) { return bindmount(arg, 1); } long syscreate(ulong *arg) { int fd; Chan *c; openmode(arg[1]); /* error check only */ fd = newfd(); validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Acreate, arg[1], arg[2]); u->fd[fd] = c; return fd; } long sysremove(ulong *arg) { Chan *c; validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Aaccess, 0, 0); if(waserror()){
1990/0703		c->type = 0; /* see below */
1990/0227		close(c); nexterror(); } (*devtab[c->type].remove)(c); /* * Remove clunks the fid, but we need to recover the Chan * so fake it up. rootclose() is known to be a nop. */ c->type = 0; close(c); return 0; } long syswstat(ulong *arg) { Chan *c; long n; validaddr(arg[1], DIRLEN, 0); evenaddr(arg[1]); validaddr(arg[0], 1, 0); c = namec((char*)arg[0], Aaccess, 0, 0); if(waserror()){ close(c); nexterror(); } (*devtab[c->type].wstat)(c, (char*)arg[1]); poperror(); close(c); return 0; } long sysfwstat(ulong *arg) { Chan *c; long n; validaddr(arg[1], DIRLEN, 0); evenaddr(arg[1]); c = fdtochan(arg[0], -1); (*devtab[c->type].wstat)(c, (char*)arg[1]); return 0; }
1990/1210		#ifdef asdf long sysfilsys(ulong *arg) { Chan *cin, *cout; cin = fdtochan(arg[0], OREAD); cout = fdtochan(arg[1], OWRITE); validaddr(arg[2], 1, 0); if((cin->qid.path&CHDIR) || (cout->qid.path&CHDIR)) error(Ebadarg); service((char *)arg[2], cin, cout, filsys); return 0; } #endif