1 /*- 2 * Copyright (c) 1982, 1986, 1991 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)tty_tty.c 7.14 (Berkeley) 05/09/91 8 */ 9 10 /* 11 * Indirect driver for controlling tty. 12 */ 13 #include "param.h" 14 #include "systm.h" 15 #include "conf.h" 16 #include "ioctl.h" 17 #include "tty.h" 18 #include "proc.h" 19 #include "vnode.h" 20 #include "file.h" 21 22 #define cttyvp(p) ((p)->p_flag&SCTTY ? (p)->p_session->s_ttyvp : NULL) 23 24 /*ARGSUSED*/ 25 cttyopen(dev, flag, mode, p) 26 dev_t dev; 27 int flag, mode; 28 struct proc *p; 29 { 30 struct vnode *ttyvp = cttyvp(p); 31 int error; 32 33 if (ttyvp == NULL) 34 return (ENXIO); 35 VOP_LOCK(ttyvp); 36 error = VOP_ACCESS(ttyvp, 37 (flag&FREAD ? VREAD : 0) | (flag&FWRITE ? VWRITE : 0), p->p_ucred, p); 38 VOP_UNLOCK(ttyvp); 39 if (error) 40 return (error); 41 return (VOP_OPEN(ttyvp, flag, NOCRED, p)); 42 } 43 44 /*ARGSUSED*/ 45 cttyread(dev, uio, flag) 46 dev_t dev; 47 struct uio *uio; 48 { 49 register struct vnode *ttyvp = cttyvp(uio->uio_procp); 50 int error; 51 52 if (ttyvp == NULL) 53 return (EIO); 54 VOP_LOCK(ttyvp); 55 error = VOP_READ(ttyvp, uio, flag, NOCRED); 56 VOP_UNLOCK(ttyvp); 57 return (error); 58 } 59 60 /*ARGSUSED*/ 61 cttywrite(dev, uio, flag) 62 dev_t dev; 63 struct uio *uio; 64 { 65 register struct vnode *ttyvp = cttyvp(uio->uio_procp); 66 int error; 67 68 if (ttyvp == NULL) 69 return (EIO); 70 VOP_LOCK(ttyvp); 71 error = VOP_WRITE(ttyvp, uio, flag, NOCRED); 72 VOP_UNLOCK(ttyvp); 73 return (error); 74 } 75 76 /*ARGSUSED*/ 77 cttyioctl(dev, cmd, addr, flag, p) 78 dev_t dev; 79 int cmd; 80 caddr_t addr; 81 int flag; 82 struct proc *p; 83 { 84 struct vnode *ttyvp = cttyvp(p); 85 86 if (ttyvp == NULL) 87 return (EIO); 88 if (cmd == TIOCNOTTY) { 89 if (!SESS_LEADER(p)) { 90 p->p_flag &= ~SCTTY; 91 return (0); 92 } else 93 return (EINVAL); 94 } 95 return (VOP_IOCTL(ttyvp, cmd, addr, flag, NOCRED, p)); 96 } 97 98 /*ARGSUSED*/ 99 cttyselect(dev, flag, p) 100 dev_t dev; 101 int flag; 102 struct proc *p; 103 { 104 struct vnode *ttyvp = cttyvp(p); 105 106 if (ttyvp == NULL) 107 return (1); /* try operation to get EOF/failure */ 108 return (VOP_SELECT(ttyvp, flag, FREAD|FWRITE, NOCRED, p)); 109 } 110