From 47eaa5f5425f847e1eaa08335344dd71bb6e0d91 Mon Sep 17 00:00:00 2001 From: Dima Dorfman Date: Tue, 22 May 2001 22:13:14 +0000 Subject: [PATCH] Convert this driver to (ab?)use line disciplines to get the input it needs instead of relying on idiosyncratic hacks in the tty subsystem. Also add module code since this can now be compiled as a module. Silence by: -hackers, -audit --- sys/dev/snp/snp.c | 101 +++++++++++++++++++++++++++++++++++-------- sys/kern/tty_snoop.c | 101 +++++++++++++++++++++++++++++++++++-------- 2 files changed, 168 insertions(+), 34 deletions(-) diff --git a/sys/dev/snp/snp.c b/sys/dev/snp/snp.c index 85609285068..8019418d480 100644 --- a/sys/dev/snp/snp.c +++ b/sys/dev/snp/snp.c @@ -15,7 +15,6 @@ * $FreeBSD$ */ -#include "opt_compat.h" #include #include #include @@ -29,6 +28,7 @@ #include #include #include +#include static d_open_t snpopen; static d_close_t snpclose; @@ -61,9 +61,63 @@ static struct cdevsw snp_cdevsw = { static MALLOC_DEFINE(M_SNP, "snp", "Snoop device data"); +#define ttytosnp(t) (struct snoop *)(t)->t_sc static struct tty *snpdevtotty __P((dev_t dev)); static int snp_detach __P((struct snoop *snp)); +/* + * The number of the "snoop" line discipline. This gets determined at + * module load time. + */ +static int mylinedisc; + +static int +dsnwrite(struct tty *tp, struct uio *uio, int flag) +{ + struct snoop *snp = ttytosnp(tp); + int error = 0; + char ibuf[1024]; + int ilen; + struct iovec iov; + struct uio uio2; + + while (uio->uio_resid) { + ilen = MIN(sizeof(ibuf), uio->uio_resid); + error = uiomove(ibuf, ilen, uio); + if (error) + break; + snpin(snp, ibuf, ilen); + /* Hackish, but I think it's the least of all evils. */ + iov.iov_base = ibuf; + iov.iov_len = ilen; + uio2.uio_iov = &iov; + uio2.uio_iovcnt = 1; + uio2.uio_offset = 0; + uio2.uio_resid = ilen; + uio2.uio_segflg = UIO_SYSSPACE; + uio2.uio_rw = UIO_WRITE; + uio2.uio_procp = uio->uio_procp; + error = ttwrite(tp, &uio2, flag); + if (error) + break; + } + return (error); +} + +/* + * XXX should there be a global version of this? + */ +static int +l_nullioctl(struct tty *tp, u_long cmd, char *data, int flags, struct proc *p) +{ + + return (ENOIOCTL); +} + +static struct linesw snpdisc = { + ttyopen, ttylclose, ttread, dsnwrite, + l_nullioctl, ttyinput, ttstart, ttymodem }; + static struct tty * snpdevtotty (dev) dev_t dev; @@ -98,7 +152,7 @@ snpwrite(dev, uio, flag) tp = snp->snp_tty; if ((tp->t_sc == snp) && (tp->t_state & TS_SNOOP) && - (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC)) + tp->t_line == mylinedisc) goto tty_input; printf("Snoop: attempt to write to bad tty.\n"); @@ -334,9 +388,10 @@ snp_detach(snp) tp = snp->snp_tty; if (tp && (tp->t_sc == snp) && (tp->t_state & TS_SNOOP) && - (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC)) { + tp->t_line == mylinedisc) { tp->t_sc = NULL; tp->t_state &= ~TS_SNOOP; + tp->t_line = snp->snp_olddisc; } else printf("Snoop: bad attached tty data.\n"); @@ -409,12 +464,6 @@ snpioctl(dev, cmd, data, flags, p) if (!tp) return (EINVAL); - if ((tp->t_sc != (caddr_t)snp) && (tp->t_state & TS_SNOOP)) - return (EBUSY); - - if ((tp->t_line != OTTYDISC) && (tp->t_line != NTTYDISC)) - return (EBUSY); - s = spltty(); if (snp->snp_target == NODEV) { @@ -425,6 +474,8 @@ snpioctl(dev, cmd, data, flags, p) tp->t_sc = (caddr_t)snp; tp->t_state |= TS_SNOOP; + snp->snp_olddisc = tp->t_line; + tp->t_line = mylinedisc; snp->snp_tty = tp; snp->snp_target = tdev; @@ -503,8 +554,6 @@ snppoll(dev, events, p) return (revents); } -static void snp_drvinit __P((void *unused)); - static void snp_clone(void *arg, char *name, int namelen, dev_t *dev) { @@ -519,13 +568,31 @@ snp_clone(void *arg, char *name, int namelen, dev_t *dev) return; } -static void -snp_drvinit(unused) - void *unused; +static int +snp_modevent(module_t mod, int type, void *data) { + static eventhandler_tag eh_tag = NULL; - EVENTHANDLER_REGISTER(dev_clone, snp_clone, 0, 1000); - cdevsw_add(&snp_cdevsw); + switch (type) { + case MOD_LOAD: + eh_tag = EVENTHANDLER_REGISTER(dev_clone, snp_clone, 0, 1000); + mylinedisc = ldisc_register(LDISC_LOAD, &snpdisc); + cdevsw_add(&snp_cdevsw); + break; + case MOD_UNLOAD: + EVENTHANDLER_DEREGISTER(dev_clone, eh_tag); + ldisc_deregister(mylinedisc); + cdevsw_remove(&snp_cdevsw); + break; + default: + break; + } + return 0; } -SYSINIT(snpdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,snp_drvinit,NULL) +static moduledata_t snp_mod = { + "snp", + snp_modevent, + NULL +}; +DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE+CDEV_MAJOR); diff --git a/sys/kern/tty_snoop.c b/sys/kern/tty_snoop.c index 85609285068..8019418d480 100644 --- a/sys/kern/tty_snoop.c +++ b/sys/kern/tty_snoop.c @@ -15,7 +15,6 @@ * $FreeBSD$ */ -#include "opt_compat.h" #include #include #include @@ -29,6 +28,7 @@ #include #include #include +#include static d_open_t snpopen; static d_close_t snpclose; @@ -61,9 +61,63 @@ static struct cdevsw snp_cdevsw = { static MALLOC_DEFINE(M_SNP, "snp", "Snoop device data"); +#define ttytosnp(t) (struct snoop *)(t)->t_sc static struct tty *snpdevtotty __P((dev_t dev)); static int snp_detach __P((struct snoop *snp)); +/* + * The number of the "snoop" line discipline. This gets determined at + * module load time. + */ +static int mylinedisc; + +static int +dsnwrite(struct tty *tp, struct uio *uio, int flag) +{ + struct snoop *snp = ttytosnp(tp); + int error = 0; + char ibuf[1024]; + int ilen; + struct iovec iov; + struct uio uio2; + + while (uio->uio_resid) { + ilen = MIN(sizeof(ibuf), uio->uio_resid); + error = uiomove(ibuf, ilen, uio); + if (error) + break; + snpin(snp, ibuf, ilen); + /* Hackish, but I think it's the least of all evils. */ + iov.iov_base = ibuf; + iov.iov_len = ilen; + uio2.uio_iov = &iov; + uio2.uio_iovcnt = 1; + uio2.uio_offset = 0; + uio2.uio_resid = ilen; + uio2.uio_segflg = UIO_SYSSPACE; + uio2.uio_rw = UIO_WRITE; + uio2.uio_procp = uio->uio_procp; + error = ttwrite(tp, &uio2, flag); + if (error) + break; + } + return (error); +} + +/* + * XXX should there be a global version of this? + */ +static int +l_nullioctl(struct tty *tp, u_long cmd, char *data, int flags, struct proc *p) +{ + + return (ENOIOCTL); +} + +static struct linesw snpdisc = { + ttyopen, ttylclose, ttread, dsnwrite, + l_nullioctl, ttyinput, ttstart, ttymodem }; + static struct tty * snpdevtotty (dev) dev_t dev; @@ -98,7 +152,7 @@ snpwrite(dev, uio, flag) tp = snp->snp_tty; if ((tp->t_sc == snp) && (tp->t_state & TS_SNOOP) && - (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC)) + tp->t_line == mylinedisc) goto tty_input; printf("Snoop: attempt to write to bad tty.\n"); @@ -334,9 +388,10 @@ snp_detach(snp) tp = snp->snp_tty; if (tp && (tp->t_sc == snp) && (tp->t_state & TS_SNOOP) && - (tp->t_line == OTTYDISC || tp->t_line == NTTYDISC)) { + tp->t_line == mylinedisc) { tp->t_sc = NULL; tp->t_state &= ~TS_SNOOP; + tp->t_line = snp->snp_olddisc; } else printf("Snoop: bad attached tty data.\n"); @@ -409,12 +464,6 @@ snpioctl(dev, cmd, data, flags, p) if (!tp) return (EINVAL); - if ((tp->t_sc != (caddr_t)snp) && (tp->t_state & TS_SNOOP)) - return (EBUSY); - - if ((tp->t_line != OTTYDISC) && (tp->t_line != NTTYDISC)) - return (EBUSY); - s = spltty(); if (snp->snp_target == NODEV) { @@ -425,6 +474,8 @@ snpioctl(dev, cmd, data, flags, p) tp->t_sc = (caddr_t)snp; tp->t_state |= TS_SNOOP; + snp->snp_olddisc = tp->t_line; + tp->t_line = mylinedisc; snp->snp_tty = tp; snp->snp_target = tdev; @@ -503,8 +554,6 @@ snppoll(dev, events, p) return (revents); } -static void snp_drvinit __P((void *unused)); - static void snp_clone(void *arg, char *name, int namelen, dev_t *dev) { @@ -519,13 +568,31 @@ snp_clone(void *arg, char *name, int namelen, dev_t *dev) return; } -static void -snp_drvinit(unused) - void *unused; +static int +snp_modevent(module_t mod, int type, void *data) { + static eventhandler_tag eh_tag = NULL; - EVENTHANDLER_REGISTER(dev_clone, snp_clone, 0, 1000); - cdevsw_add(&snp_cdevsw); + switch (type) { + case MOD_LOAD: + eh_tag = EVENTHANDLER_REGISTER(dev_clone, snp_clone, 0, 1000); + mylinedisc = ldisc_register(LDISC_LOAD, &snpdisc); + cdevsw_add(&snp_cdevsw); + break; + case MOD_UNLOAD: + EVENTHANDLER_DEREGISTER(dev_clone, eh_tag); + ldisc_deregister(mylinedisc); + cdevsw_remove(&snp_cdevsw); + break; + default: + break; + } + return 0; } -SYSINIT(snpdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,snp_drvinit,NULL) +static moduledata_t snp_mod = { + "snp", + snp_modevent, + NULL +}; +DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE+CDEV_MAJOR);