1991/0319/port/sysfile.c (diff list | history)

1991/0319/sys/src/9/port/sysfile.c:191,197 – 1991/0411/sys/src/9/port/sysfile.c:191,197 (short | long | prev | next)
Bug fix: add explicit read lock and write lock instead of using channel's qlock. This way a process can write even if another process is blocked doing a read. Add explicit offset to dev read and write to accomodate this. rsc Fri Mar 4 17:11:43 2005
1990/0227		} nc = (*devtab[nc->type].open)(nc, OREAD); nc->offset = c->offset; nr = (*devtab[nc->type].read)(nc, va, n);
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();
1991/0319/sys/src/9/port/sysfile.c:226,234 – 1991/0411/sys/src/9/port/sysfile.c:226,234
1990/0227
1990/1009		c = fdtochan(arg[0], OREAD);
1990/1004		validaddr(arg[1], arg[2], 1);
1990/0227		qlock(c);
1991/0411		qlock(&c->rdl);
1990/0227		if(waserror()){ qunlock(c);
1991/0411		qunlock(&c->rdl);
1990/0227		nexterror(); } n = arg[2];
1991/0319/sys/src/9/port/sysfile.c:240,248 – 1991/0411/sys/src/9/port/sysfile.c:240,248
1990/11211		if((c->qid.path&CHDIR) && (c->flag&CMOUNT))
1990/0227		n = unionread(c, (void*)arg[1], n); else n = (*devtab[c->type].read)(c, (void*)arg[1], n);
1991/0411		n = (*devtab[c->type].read)(c, (void*)arg[1], n, c->offset);
1990/0227		c->offset += n; qunlock(c);
1991/0411		qunlock(&c->rdl);
1990/0227		return n; }
1991/0319/sys/src/9/port/sysfile.c:254,269 – 1991/0411/sys/src/9/port/sysfile.c:254,269
1990/0227
1990/1009		c = fdtochan(arg[0], OWRITE);
1990/0227		validaddr(arg[1], arg[2], 0); qlock(c);
1991/0411		qlock(&c->wrl);
1990/0227		if(waserror()){ qunlock(c);
1991/0411		qunlock(&c->wrl);
1990/0227		nexterror(); }
1990/11211		if(c->qid.path & CHDIR) error(Eisdir);
1990/0227		n = (*devtab[c->type].write)(c, (void*)arg[1], arg[2]);
1991/0411		n = (*devtab[c->type].write)(c, (void*)arg[1], arg[2], c->offset);
1990/0227		c->offset += n; qunlock(c);
1991/0411		qunlock(&c->wrl);
1990/0227		return n; }
1991/0319/sys/src/9/port/sysfile.c:280,288 – 1991/0411/sys/src/9/port/sysfile.c:280,290
1990/11211		error(Eisdir);
1991/0319		if(devchar[c->type] == '|') error(Eisstream);
1990/0227		qlock(c);
1991/0411		qlock(&c->rdl); qlock(&c->wrl);
1990/0227		if(waserror()){ qunlock(c);
1991/0411		qunlock(&c->rdl); qunlock(&c->wrl);
1990/0227		nexterror(); } switch(arg[2]){
1991/0319/sys/src/9/port/sysfile.c:301,307 – 1991/0411/sys/src/9/port/sysfile.c:303,310
1990/0227		break; } off = c->offset; qunlock(c);
1991/0411		qunlock(&c->rdl); qunlock(&c->wrl);
1990/0227		poperror(); return off; }