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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 | /* * Copyright (c) 2000-2007 Apple Inc. All rights reserved. */ /* * Copyright (c) 1987, 1988 NeXT, Inc. * * HISTORY 7-Jan-93 Mac Gillon (mgillon) at NeXT Integrated POSIX support * * 12-Aug-87 John Seamons (jks) at NeXT Ported to NeXT. */ /* * Indirect driver for console. */ #include <kern/locks.h> #include <machine/cons.h> #include <sys/param.h> #include <sys/systm.h> #include <sys/conf.h> #include <sys/ioctl.h> #include <sys/tty.h> #include <sys/proc.h> #include <sys/uio.h> static struct tty *_constty; /* current console device */ static LCK_GRP_DECLARE(_constty_lock_grp, "constty"); static LCK_MTX_DECLARE(_constty_lock, &_constty_lock_grp); struct tty * copy_constty(void) { struct tty *result = NULL; lck_mtx_lock(&_constty_lock); if (_constty != NULL) { ttyhold(_constty); result = _constty; } lck_mtx_unlock(&_constty_lock); return result; } struct tty * set_constty(struct tty *new_tty) { struct tty *old_tty = NULL; lck_mtx_lock(&_constty_lock); old_tty = _constty; _constty = new_tty; if (_constty) { ttyhold(_constty); } lck_mtx_unlock(&_constty_lock); return old_tty; } /* * The km driver supplied the default console device for the systems * (usually a raw frame buffer driver, but potentially a serial driver). */ extern struct tty *km_tty[1]; /* * cdevsw[] entries for the console device driver */ int cnopen(__unused dev_t dev, int flag, int devtype, proc_t pp); int cnclose(__unused dev_t dev, int flag, int mode, proc_t pp); int cnread(__unused dev_t dev, struct uio *uio, int ioflag); int cnwrite(__unused dev_t dev, struct uio *uio, int ioflag); int cnioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flg, proc_t p); int cnselect(__unused dev_t dev, int flag, void * wql, proc_t p); int cnopen(__unused dev_t dev, int flag, int devtype, struct proc *pp) { int error; struct tty *constty = copy_constty(); if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } error = (*cdevsw[major(dev)].d_open)(dev, flag, devtype, pp); if (constty != NULL) { ttyfree(constty); } return error; } int cnclose(__unused dev_t dev, int flag, int mode, struct proc *pp) { int error; struct tty *constty = copy_constty(); if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } error = (*cdevsw[major(dev)].d_close)(dev, flag, mode, pp); if (constty != NULL) { ttyfree(constty); } return error; } int cnread(__unused dev_t dev, struct uio *uio, int ioflag) { int error; struct tty *constty = copy_constty(); if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } error = (*cdevsw[major(dev)].d_read)(dev, uio, ioflag); if (constty != NULL) { ttyfree(constty); } return error; } int cnwrite(__unused dev_t dev, struct uio *uio, int ioflag) { int error; struct tty *constty = copy_constty(); if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } error = (*cdevsw[major(dev)].d_write)(dev, uio, ioflag); if (constty != NULL) { ttyfree(constty); } return error; } int cnioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) { int error; struct tty *constty = copy_constty(); struct tty *freetp = NULL; if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } /* * XXX This check prevents the cons.c code from being shared between * XXX all architectures; it is probably not needed on ARM, either, * XXX but I have no test platforms or ability to run a kernel. * * Superuser can always use this to wrest control of console * output from the "virtual" console. */ if ((unsigned) cmd == TIOCCONS && constty) { error = proc_suser(p); if (error) { goto finish; } freetp = set_constty(NULL); if (freetp) { ttyfree(freetp); freetp = NULL; } } else { error = (*cdevsw[major(dev)].d_ioctl)(dev, cmd, addr, flag, p); } finish: if (constty != NULL) { ttyfree(constty); } return error; } int cnselect(__unused dev_t dev, int flag, void *wql, struct proc *p) { int error; struct tty *constty = copy_constty(); if (constty) { dev = constty->t_dev; } else { dev = km_tty[0]->t_dev; } error = (*cdevsw[major(dev)].d_select)(dev, flag, wql, p); if (constty != NULL) { ttyfree(constty); } return error; } |