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linux_misc_notalpha.c revision 1.1
      1 /*	$NetBSD: linux_misc_notalpha.c,v 1.1 1995/02/28 23:25:07 fvdl Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1995 Frank van der Linden
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *      This product includes software developed for the NetBSD Project
     18  *      by Frank van der Linden
     19  * 4. The name of the author may not be used to endorse or promote products
     20  *    derived from this software without specific prior written permission
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     32  */
     33 
     34 /*
     35  * Linux compatibility module. Try to deal with various Linux system calls.
     36  */
     37 
     38 #include <sys/param.h>
     39 #include <sys/systm.h>
     40 #include <sys/namei.h>
     41 #include <sys/proc.h>
     42 #include <sys/dir.h>
     43 #include <sys/file.h>
     44 #include <sys/stat.h>
     45 #include <sys/filedesc.h>
     46 #include <sys/ioctl.h>
     47 #include <sys/kernel.h>
     48 #include <sys/malloc.h>
     49 #include <sys/mbuf.h>
     50 #include <sys/mman.h>
     51 #include <sys/mount.h>
     52 #include <sys/ptrace.h>
     53 #include <sys/resource.h>
     54 #include <sys/resourcevar.h>
     55 #include <sys/signal.h>
     56 #include <sys/signalvar.h>
     57 #include <sys/socket.h>
     58 #include <sys/time.h>
     59 #include <sys/times.h>
     60 #include <sys/vnode.h>
     61 #include <sys/uio.h>
     62 #include <sys/wait.h>
     63 #include <sys/utsname.h>
     64 #include <sys/unistd.h>
     65 
     66 #include <sys/syscallargs.h>
     67 
     68 #include <vm/vm.h>
     69 #include <vm/vm_param.h>
     70 
     71 #include <compat/linux/linux_types.h>
     72 #include <compat/linux/linux_fcntl.h>
     73 #include <compat/linux/linux_mmap.h>
     74 #include <compat/linux/linux_syscallargs.h>
     75 #include <compat/linux/linux_util.h>
     76 #include <compat/linux/linux_dirent.h>
     77 
     78 /*
     79  * The information on a terminated (or stopped) process needs
     80  * to be converted in order for Linux binaries to get a valid signal
     81  * number out of it.
     82  */
     83 static int
     84 bsd_to_linux_wstat(status)
     85 	int *status;
     86 {
     87 	if (WIFSIGNALED(*status))
     88 		*status = (*status & ~0177) |
     89 		    bsd_to_linux_sig(WTERMSIG(*status));
     90 	else if (WIFSTOPPED(*status))
     91 		*status = (*status & ~0xff00) |
     92 		    (bsd_to_linux_sig(WSTOPSIG(*status)) << 8);
     93 }
     94 
     95 /*
     96  * waitpid(2). Passed on to the NetBSD call, surrounded by code to
     97  * reserve some space for a NetBSD-style wait status, and converting
     98  * it to what Linux wants.
     99  */
    100 int
    101 linux_waitpid(p, uap, retval)
    102 	struct proc *p;
    103 	struct linux_waitpid_args /* {
    104 		syscallarg(int) pid;
    105 		syscallarg(int *) status;
    106 		syscallarg(int) options;
    107 	} */ *uap;
    108 	register_t *retval;
    109 {
    110 	struct wait4_args w4a;
    111 	int error, *status, tstat;
    112 	caddr_t sg;
    113 
    114 	sg = stackgap_init();
    115 	status = (int *) stackgap_alloc(&sg, sizeof status);
    116 
    117 	SCARG(&w4a, pid) = SCARG(uap, pid);
    118 	SCARG(&w4a, status) = status;
    119 	SCARG(&w4a, options) = SCARG(uap, options);
    120 	SCARG(&w4a, rusage) = NULL;
    121 
    122 	if ((error = wait4(p, &w4a, retval)))
    123 		return error;
    124 
    125 	if ((error = copyin(status, &tstat, sizeof tstat)))
    126 		return error;
    127 
    128 	bsd_to_linux_wstat(&tstat);
    129 
    130 	return copyout(&tstat, SCARG(uap, status), sizeof tstat);
    131 }
    132 
    133 /*
    134  * This is very much the same as waitpid()
    135  */
    136 int
    137 linux_wait4(p, uap, retval)
    138 	struct proc *p;
    139 	struct linux_wait4_args /* {
    140 		syscallarg(int) pid;
    141 		syscallarg(int *) status;
    142 		syscallarg(int) options;
    143 		syscallarg(struct rusage *) rusage;
    144 	} */ *uap;
    145 	register_t *retval;
    146 {
    147 	struct wait4_args w4a;
    148 	int error, *status, tstat;
    149 	caddr_t sg;
    150 
    151 	sg = stackgap_init();
    152 	status = (int *) stackgap_alloc(&sg, sizeof status);
    153 
    154 	SCARG(&w4a, pid) = SCARG(uap, pid);
    155 	SCARG(&w4a, status) = status;
    156 	SCARG(&w4a, options) = SCARG(uap, options);
    157 	SCARG(&w4a, rusage) = SCARG(uap, rusage);
    158 
    159 	if ((error = wait4(p, &w4a, retval)))
    160 		return error;
    161 
    162 	if ((error = copyin(status, &tstat, sizeof tstat)))
    163 		return error;
    164 
    165 	bsd_to_linux_wstat(&tstat);
    166 
    167 	return copyout(&tstat, SCARG(uap, status), sizeof tstat);
    168 }
    169 
    170 /*
    171  * This is the old brk(2) call. I don't think anything in the Linux
    172  * world uses this anymore
    173  */
    174 int
    175 linux_break(p, uap, retval)
    176 	struct proc *p;
    177 	struct linux_brk_args /* {
    178 		syscallarg(char *) nsize;
    179 	} */ *uap;
    180 	register_t *retval;
    181 {
    182 	return ENOSYS;
    183 }
    184 
    185 /*
    186  * Linux brk(2). The check if the new address is >= the old one is
    187  * done in the kernel in Linux. NetBSD does it in the library.
    188  */
    189 int
    190 linux_brk(p, uap, retval)
    191 	struct proc *p;
    192 	struct linux_brk_args /* {
    193 		syscallarg(char *) nsize;
    194 	} */ *uap;
    195 	register_t *retval;
    196 {
    197 	char *nbrk = SCARG(uap, nsize);
    198 	struct obreak_args oba;
    199 	struct vmspace *vm = p->p_vmspace;
    200 	int error = 0;
    201 	caddr_t oldbrk, newbrk;
    202 
    203 	oldbrk = vm->vm_daddr + ctob(vm->vm_dsize);
    204 	/*
    205 	 * XXX inconsistent.. Linux always returns at least the old
    206 	 * brk value, but it will be page-aligned if this fails,
    207 	 * and possibly not page aligned if it succeeds (the user
    208 	 * supplied pointer is returned).
    209 	 */
    210 	SCARG(&oba, nsize) = nbrk;
    211 
    212 	if ((caddr_t) nbrk > vm->vm_daddr && obreak(p, &oba, retval) == 0)
    213 		retval[0] = (register_t) nbrk;
    214 	else
    215 		retval[0] = (register_t) oldbrk;
    216 
    217 	return 0;
    218 }
    219 
    220 /*
    221  * I wonder why Linux has gettimeofday() _and_ time().. Still, we
    222  * need to deal with it.
    223  */
    224 int
    225 linux_time(p, uap, retval)
    226 	struct proc *p;
    227 	struct linux_time_args /* {
    228 		linux_time_t *t;
    229 	} */ *uap;
    230 	register_t *retval;
    231 {
    232 	struct timeval atv;
    233 	linux_time_t tt;
    234 	int error;
    235 
    236 	microtime(&atv);
    237 
    238 	tt = atv.tv_sec;
    239 	if (SCARG(uap, t) && (error = copyout(&tt, SCARG(uap, t), sizeof tt)))
    240 		return error;
    241 
    242 	retval[0] = tt;
    243 	return 0;
    244 }
    245 
    246 /*
    247  * The statfs and fstatfs called are not implemented yet. They're
    248  * easy, but just not important for the binaries I wanted to get
    249  * running.
    250  */
    251 int
    252 linux_statfs(p, uap, retval)
    253 	struct proc *p;
    254 	struct linux_statfs_args /* {
    255 		syscallarg(char *) path;
    256 		syscallarg(struct linux_statfs *) sp;
    257 	} */ *uap;
    258 	register_t *retval;
    259 {
    260 	return ENOSYS;
    261 }
    262 
    263 int
    264 linux_fstatfs(p, uap, retval)
    265 	struct proc *p;
    266 	struct linux_fstatfs_args /* {
    267 		syscallarg(char *) path;
    268 		syscallarg(struct linux_statfs *) sp;
    269 	} */ *uap;
    270 	register_t *retval;
    271 {
    272 	return ENOSYS;
    273 }
    274 
    275 /*
    276  * uname(). Just copy the info from the various strings stored in the
    277  * kernel, and put it in the Linux utsname structure. That structure
    278  * is almost the same as the NetBSD one, only it has fields 65 characters
    279  * long, and an extra domainname field.
    280  */
    281 int
    282 linux_uname(p, uap, retval)
    283 	struct proc *p;
    284 	struct linux_uname_args /* {
    285 		syscallarg(struct linux_utsname *) up;
    286 	} */ *uap;
    287 	register_t *retval;
    288 {
    289 	extern char ostype[], osrelease[], version[], hostname[], domainname[];
    290 	extern char machine[];
    291 	struct linux_utsname tluts;
    292 	int len;
    293 	char *cp;
    294 
    295 	strncpy(tluts.l_sysname, ostype, sizeof (tluts.l_sysname));
    296 	strncpy(tluts.l_nodename, hostname, sizeof (tluts.l_nodename));
    297 	strncpy(tluts.l_release, osrelease, sizeof (tluts.l_release));
    298 	strncpy(tluts.l_machine, machine, sizeof (tluts.l_machine));
    299 	strncpy(tluts.l_domainname, domainname, sizeof (tluts.l_domainname));
    300 	strncpy(tluts.l_version, version, sizeof (tluts.l_version));
    301 
    302 	/* This part taken from the the uname() in libc */
    303 	len = sizeof (tluts.l_version);
    304 	for (cp = tluts.l_version; len--; ++cp)
    305 		if (*cp == '\n' || *cp == '\t')
    306 			if (len > 1)
    307 				*cp = ' ';
    308 			else
    309 				*cp = '\0';
    310 
    311 	return copyout(&tluts, SCARG(uap, up), sizeof tluts);
    312 }
    313 
    314 /*
    315  * Linux wants to pass everything to a syscall in registers. However,
    316  * mmap() has 6 of them. Oops: out of register error. They just pass
    317  * everything in a structure.
    318  */
    319 int
    320 linux_mmap(p, uap, retval)
    321 	struct proc *p;
    322 	struct linux_mmap_args /* {
    323 		syscallarg(struct linux_mmap *) lmp;
    324 	} */ *uap;
    325 	register_t *retval;
    326 {
    327 	struct linux_mmap lmap;
    328 	struct mmap_args cma;
    329 	int error, flags;
    330 
    331 	if ((error = copyin(SCARG(uap, lmp), &lmap, sizeof lmap)))
    332 		return error;
    333 
    334 	flags = 0;
    335 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_SHARED, MAP_SHARED);
    336 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_PRIVATE, MAP_PRIVATE);
    337 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_FIXED, MAP_FIXED);
    338 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_ANON, MAP_ANON);
    339 
    340 	SCARG(&cma,addr) = lmap.lm_addr;
    341 	SCARG(&cma,len) = lmap.lm_len;
    342  	SCARG(&cma,prot) = lmap.lm_prot;
    343 	SCARG(&cma,flags) = flags;
    344 	SCARG(&cma,fd) = lmap.lm_fd;
    345 	SCARG(&cma,pad) = 0;
    346 	SCARG(&cma,pos) = lmap.lm_pos;
    347 
    348 	return mmap(p, &cma, retval);
    349 }
    350 
    351 /*
    352  * Linux doesn't use the retval[1] value to determine whether
    353  * we are the child or parent.
    354  */
    355 int
    356 linux_fork(p, uap, retval)
    357 	struct proc *p;
    358 	void *uap;
    359 	register_t *retval;
    360 {
    361 	int error;
    362 
    363 	if ((error = fork(p, uap, retval)))
    364 		return error;
    365 
    366 	if (retval[1] == 1)
    367 		retval[0] = 0;
    368 
    369 	return 0;
    370 }
    371 
    372 /*
    373  * This code is partly stolen from src/lib/libc/compat-43/times.c
    374  * XXX - CLK_TCK isn't declared in /sys, just in <time.h>, done here
    375  */
    376 
    377 #define CLK_TCK 100
    378 #define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))
    379 
    380 int
    381 linux_times(p, uap, retval)
    382 	struct proc *p;
    383 	struct linux_times_args /* {
    384 		syscallarg(struct times *) tms;
    385 	} */ *uap;
    386 	register_t *retval;
    387 {
    388 	struct timeval t;
    389 	struct linux_tms ltms;
    390 	struct rusage ru;
    391 	int error;
    392 
    393 	calcru(p, &ru.ru_utime, &ru.ru_stime, NULL);
    394 	ltms.ltms_utime = CONVTCK(ru.ru_utime);
    395 	ltms.ltms_stime = CONVTCK(ru.ru_stime);
    396 
    397 	ltms.ltms_cutime = CONVTCK(p->p_stats->p_cru.ru_utime);
    398 	ltms.ltms_cstime = CONVTCK(p->p_stats->p_cru.ru_stime);
    399 
    400 	if ((error = copyout(&ltms, SCARG(uap, tms), sizeof ltms)))
    401 		return error;
    402 
    403 	microtime(&t);
    404 
    405 	retval[0] = ((linux_clock_t)(CONVTCK(t)));
    406 	return 0;
    407 }
    408 
    409 /*
    410  * NetBSD passes fd[0] in retval[0], and fd[1] in retval[1].
    411  * Linux directly passes the pointer.
    412  */
    413 int
    414 linux_pipe(p, uap, retval)
    415 	struct proc *p;
    416 	struct linux_pipe_args /* {
    417 		syscallarg(int *) pfds;
    418 	} */ *uap;
    419 	register_t *retval;
    420 {
    421 	int error;
    422 
    423 	if ((error = pipe(p, 0, retval)))
    424 		return error;
    425 
    426 	/* Assumes register_t is an int */
    427 
    428 	if ((error = copyout(retval, SCARG(uap, pfds), 2 * sizeof (int))))
    429 		return error;
    430 
    431 	retval[0] = 0;
    432 	return 0;
    433 }
    434 
    435 /*
    436  * Alarm. This is a libc call which used setitimer(2) in NetBSD.
    437  * Fiddle with the timers to make it work.
    438  */
    439 int
    440 linux_alarm(p, uap, retval)
    441 	struct proc *p;
    442 	struct linux_alarm_args /* {
    443 		syscallarg(unsigned int) secs;
    444 	} */ *uap;
    445 	register_t *retval;
    446 {
    447 	int error, s;
    448 	struct itimerval *itp, it;
    449 
    450 	itp = &p->p_realtimer;
    451 	s = splclock();
    452 	/*
    453 	 * Clear any pending timer alarms.
    454 	 */
    455 	untimeout(realitexpire, p);
    456 	timerclear(&itp->it_interval);
    457 	if (timerisset(&itp->it_value) &&
    458 	    timercmp(&itp->it_value, &time, >))
    459 		__timersub(&itp->it_value, &time);
    460 	/*
    461 	 * Return how many seconds were left (rounded up)
    462 	 */
    463 	retval[0] = itp->it_value.tv_sec;
    464 	if (itp->it_value.tv_usec)
    465 		retval[0]++;
    466 
    467 	/*
    468 	 * alarm(0) just resets the timer.
    469 	 */
    470 	if (SCARG(uap, secs) == 0) {
    471 		timerclear(&itp->it_value);
    472 		splx(s);
    473 		return 0;
    474 	}
    475 
    476 	/*
    477 	 * Check the new alarm time for sanity, and set it.
    478 	 */
    479 	timerclear(&it.it_interval);
    480 	it.it_value.tv_sec = SCARG(uap, secs);
    481 	it.it_value.tv_usec = 0;
    482 	if (itimerfix(&it.it_value) || itimerfix(&it.it_interval)) {
    483 		splx(s);
    484 		return (EINVAL);
    485 	}
    486 
    487 	if (timerisset(&it.it_value)) {
    488 		__timeradd(&it.it_value, &time);
    489 		timeout(realitexpire, p, hzto(&it.it_value));
    490 	}
    491 	p->p_realtimer = it;
    492 	splx(s);
    493 
    494 	return 0;
    495 }
    496 
    497 /*
    498  * utime(). Do conversion to things that utimes() understands,
    499  * and pass it on.
    500  */
    501 int
    502 linux_utime(p, uap, retval)
    503 	struct proc *p;
    504 	struct linux_utime_args /* {
    505 		syscallarg(char *) path;
    506 		syscallarg(struct linux_utimbuf *)times;
    507 	} */ *uap;
    508 	register_t *retval;
    509 {
    510 	caddr_t sg;
    511 	int error;
    512 	struct utimes_args ua;
    513 	struct timeval tv[2], *tvp;
    514 	struct linux_utimbuf lut;
    515 
    516 	sg = stackgap_init();
    517 	CHECK_ALT(p, &sg, SCARG(uap, path));
    518 
    519 	SCARG(&ua, path) = SCARG(uap, path);
    520 
    521 	if (SCARG(uap, times) != NULL) {
    522 		if ((error = copyin(SCARG(uap, times), &lut, sizeof lut)))
    523 			return error;
    524 		tv[0].tv_usec = tv[1].tv_usec = 0;
    525 		tv[0].tv_sec = lut.l_actime;
    526 		tv[1].tv_sec = lut.l_modtime;
    527 		tvp = (struct timeval *) stackgap_alloc(sizeof tv);
    528 		if ((error = copyout(tv, tvp, sizeof tv)))
    529 			return error;
    530 		SCARG(&ua, tptr) = tvp;
    531 	}
    532 	else
    533 		SCARG(&ua, tptr) = NULL;
    534 
    535 	return utimes(p, uap, retval);
    536 }
    537 
    538 /*
    539  * Linux 'readdir' call. This code is mostly taken from the
    540  * SunOS getdents call (see compat/sunos/sunos_misc.c), though
    541  * an attempt has been made to keep it a little cleaner (failing
    542  * miserably, because of the cruft needed if count 1 is passed).
    543  *
    544  * Read in BSD-style entries, convert them, and copy them out.
    545  * Note that the Linux d_reclen is actually the name length,
    546  * and d_off is the reclen.
    547  *
    548  * Note that this doesn't handle union-mounted filesystems.
    549  */
    550 int
    551 linux_readdir(p, uap, retval)
    552 	struct proc *p;
    553 	struct linux_readdir_args /* {
    554 		syscallarg(int) fd;
    555 		syscallarg(struct linux_dirent *) dent;
    556 		syscallarg(unsigned int) count;
    557 	} */ *uap;
    558 	register_t *retval;
    559 {
    560 	register struct dirent *bdp;
    561 	struct vnode *vp;
    562 	caddr_t	inp, buf;	/* BSD-format */
    563 	int len, reclen;	/* BSD-format */
    564 	caddr_t outp;		/* Linux-format */
    565 	int resid, linuxreclen;	/* Linux-format */
    566 	struct file *fp;
    567 	struct uio auio;
    568 	struct iovec aiov;
    569 	struct linux_dirent idb;
    570 	off_t off;		/* true file offset */
    571 	linux_off_t soff;	/* Linux file offset */
    572 	int buflen, error, eofflag, nbytes, justone;
    573 	struct vattr va;
    574 
    575 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
    576 		return (error);
    577 
    578 	if ((fp->f_flag & FREAD) == 0)
    579 		return (EBADF);
    580 
    581 	vp = (struct vnode *) fp->f_data;
    582 
    583 	if (vp->v_type != VDIR)	/* XXX  vnode readdir op should do this */
    584 		return (EINVAL);
    585 
    586 	if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p)))
    587 		return error;
    588 
    589 	nbytes = SCARG(uap, count);
    590 	if (nbytes == 1) {	/* Need this for older Linux libs, apparently */
    591 		nbytes = sizeof (struct linux_dirent);
    592 		justone = 1;
    593 	}
    594 	else
    595 		justone = 0;
    596 
    597 	buflen = max(va.va_blocksize, nbytes);
    598 	buf = malloc(buflen, M_TEMP, M_WAITOK);
    599 	VOP_LOCK(vp);
    600 	off = fp->f_offset;
    601 again:
    602 	aiov.iov_base = buf;
    603 	aiov.iov_len = buflen;
    604 	auio.uio_iov = &aiov;
    605 	auio.uio_iovcnt = 1;
    606 	auio.uio_rw = UIO_READ;
    607 	auio.uio_segflg = UIO_SYSSPACE;
    608 	auio.uio_procp = p;
    609 	auio.uio_resid = buflen;
    610 	auio.uio_offset = off;
    611 	/*
    612          * First we read into the malloc'ed buffer, then
    613          * we massage it into user space, one record at a time.
    614          */
    615 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, (u_long *) 0, 0);
    616 	if (error)
    617 		goto out;
    618 
    619 	inp = buf;
    620 	outp = (caddr_t) SCARG(uap, dent);
    621 	resid = nbytes;
    622 	if ((len = buflen - auio.uio_resid) == 0)
    623 		goto eof;
    624 
    625 	for (; len > 0; len -= reclen) {
    626 		reclen = ((struct dirent *) inp)->d_reclen;
    627 		if (reclen & 3)
    628 			panic("linux_readdir");
    629 		off += reclen;	/* each entry points to next */
    630 		bdp = (struct dirent *) inp;
    631 		if (bdp->d_fileno == 0) {
    632 			inp += reclen;	/* it is a hole; squish it out */
    633 			continue;
    634 		}
    635 		linuxreclen = LINUX_RECLEN(&idb, bdp->d_namlen);
    636 		if (reclen > len || resid < linuxreclen) {
    637 			/* entry too big for buffer, so just stop */
    638 			outp++;
    639 			break;
    640 		}
    641 		/*
    642 		 * Massage in place to make a Linux-shaped dirent (otherwise
    643 		 * we have to worry about touching user memory outside of
    644 		 * the copyout() call).
    645 		 */
    646 		idb.l_dino = (long) bdp->d_fileno;
    647 		idb.l_doff = (linux_off_t) linuxreclen;
    648 		idb.l_dreclen = (u_short) bdp->d_namlen;	/* sigh */
    649 		strcpy(idb.l_dname, bdp->d_name);
    650 		if ((error = copyout((caddr_t)&idb, outp, linuxreclen)))
    651 			goto out;
    652 		/* advance past this real entry */
    653 		inp += reclen;
    654 		/* advance output past Linux-shaped entry */
    655 		outp += linuxreclen;
    656 		resid -= linuxreclen;
    657 		if (justone)
    658 			break;
    659 	}
    660 
    661 	/* if we squished out the whole block, try again */
    662 	if (outp == (caddr_t) SCARG(uap, dent))
    663 		goto again;
    664 	fp->f_offset = off;	/* update the vnode offset */
    665 
    666 	if (justone)
    667 		nbytes = resid + linuxreclen;
    668 
    669 eof:
    670 	*retval = nbytes - resid;
    671 out:
    672 	VOP_UNLOCK(vp);
    673 	free(buf, M_TEMP);
    674 	return error;
    675 }
    676 
    677 /*
    678  * Out of register error once more.. Apart from that, no difference.
    679  */
    680 int
    681 linux_select(p, uap, retval)
    682 	struct proc *p;
    683 	struct linux_select_args /* {
    684 		syscallarg(struct linux_select *) lsp;
    685 	} */ *uap;
    686 	register_t *retval;
    687 {
    688 	struct linux_select ls;
    689 	struct select_args bsa;
    690 	int error;
    691 
    692 	if ((error = copyin(SCARG(uap, lsp), (caddr_t) &ls, sizeof ls)))
    693 		return error;
    694 
    695 	SCARG(&bsa, nd) = ls.nfds;
    696 	SCARG(&bsa, in) = ls.readfds;
    697 	SCARG(&bsa, ou) = ls.writefds;
    698 	SCARG(&bsa, ex) = ls.exceptfds;
    699 	SCARG(&bsa, tv) = ls.timeout;
    700 
    701 	return select(p, &bsa, retval);
    702 }
    703 
    704 /*
    705  * Get the process group of a certain process. Look it up
    706  * and return the value.
    707  */
    708 int
    709 linux_getpgid(p, uap, retval)
    710 	struct proc *p;
    711 	struct linux_getpgid_args /* {
    712 		syscallarg(int) pid;
    713 	} */ *uap;
    714 	register_t *retval;
    715 {
    716 	struct proc *targp;
    717 
    718 	if (SCARG(uap, pid) != 0 && SCARG(uap, pid) != p->p_pid)
    719 		if ((targp = pfind(SCARG(uap, pid))) == 0)
    720 			return ESRCH;
    721 	else
    722 		targp = p;
    723 
    724 	retval[0] = targp->p_pgid;
    725 	return 0;
    726 }
    727