freebsd-skq/usr.sbin/lpr/common_source/common.c
gad 92ccb9a78d Change the closeallfds() routine to use closefrom() when it is
available (closefrom() was added to FreeBSD in 8.0-release).
The selection is made at compile-time, as I still compile a
FreeBSD-based version of lpr&friends on other platforms.

While testing I out that (at least on my system) lpd has been
closing 11095 fd's, when there are only 6 fd's open.  The old
code took 120 times more clocktime than calling closefrom().
(although that was still less than 2/1000-ths of a second!)

Reviewed by:	jilles
MFC after:	2 weeks
2013-05-27 22:19:01 +00:00

779 lines
22 KiB
C

/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)common.c 8.5 (Berkeley) 4/28/95";
#endif /* not lint */
#endif
#include "lp.cdefs.h" /* A cross-platform version of <sys/cdefs.h> */
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "lp.h"
#include "lp.local.h"
#include "pathnames.h"
/*
* Routines and data common to all the line printer functions.
*/
char line[BUFSIZ];
const char *progname; /* program name */
static int compar(const void *_p1, const void *_p2);
/*
* isdigit() takes a parameter of 'int', but expect values in the range
* of unsigned char. Define a wrapper which takes a value of type 'char',
* whether signed or unsigned, and ensure it ends up in the right range.
*/
#define isdigitch(Anychar) isdigit((u_char)(Anychar))
/*
* Getline reads a line from the control file cfp, removes tabs, converts
* new-line to null and leaves it in line.
* Returns 0 at EOF or the number of characters read.
*/
int
getline(FILE *cfp)
{
register int linel = 0;
register char *lp = line;
register int c;
while ((c = getc(cfp)) != '\n' && (size_t)(linel+1) < sizeof(line)) {
if (c == EOF)
return(0);
if (c == '\t') {
do {
*lp++ = ' ';
linel++;
} while ((linel & 07) != 0 && (size_t)(linel+1) <
sizeof(line));
continue;
}
*lp++ = c;
linel++;
}
*lp++ = '\0';
return(linel);
}
/*
* Scan the current directory and make a list of daemon files sorted by
* creation time.
* Return the number of entries and a pointer to the list.
*/
int
getq(const struct printer *pp, struct jobqueue *(*namelist[]))
{
register struct dirent *d;
register struct jobqueue *q, **queue;
size_t arraysz, entrysz, nitems;
struct stat stbuf;
DIR *dirp;
int statres;
PRIV_START
if ((dirp = opendir(pp->spool_dir)) == NULL) {
PRIV_END
return (-1);
}
if (fstat(dirfd(dirp), &stbuf) < 0)
goto errdone;
PRIV_END
/*
* Estimate the array size by taking the size of the directory file
* and dividing it by a multiple of the minimum size entry.
*/
arraysz = (stbuf.st_size / 24);
if (arraysz < 16)
arraysz = 16;
queue = (struct jobqueue **)malloc(arraysz * sizeof(struct jobqueue *));
if (queue == NULL)
goto errdone;
nitems = 0;
while ((d = readdir(dirp)) != NULL) {
if (d->d_name[0] != 'c' || d->d_name[1] != 'f')
continue; /* daemon control files only */
PRIV_START
statres = stat(d->d_name, &stbuf);
PRIV_END
if (statres < 0)
continue; /* Doesn't exist */
entrysz = sizeof(struct jobqueue) - sizeof(q->job_cfname) +
strlen(d->d_name) + 1;
q = (struct jobqueue *)malloc(entrysz);
if (q == NULL)
goto errdone;
q->job_matched = 0;
q->job_processed = 0;
q->job_time = stbuf.st_mtime;
strcpy(q->job_cfname, d->d_name);
/*
* Check to make sure the array has space left and
* realloc the maximum size.
*/
if (++nitems > arraysz) {
arraysz *= 2;
queue = (struct jobqueue **)realloc((char *)queue,
arraysz * sizeof(struct jobqueue *));
if (queue == NULL)
goto errdone;
}
queue[nitems-1] = q;
}
closedir(dirp);
if (nitems)
qsort(queue, nitems, sizeof(struct jobqueue *), compar);
*namelist = queue;
return(nitems);
errdone:
closedir(dirp);
PRIV_END
return (-1);
}
/*
* Compare modification times.
*/
static int
compar(const void *p1, const void *p2)
{
const struct jobqueue *qe1, *qe2;
qe1 = *(const struct jobqueue * const *)p1;
qe2 = *(const struct jobqueue * const *)p2;
if (qe1->job_time < qe2->job_time)
return (-1);
if (qe1->job_time > qe2->job_time)
return (1);
/*
* At this point, the two files have the same last-modification time.
* return a result based on filenames, so that 'cfA001some.host' will
* come before 'cfA002some.host'. Since the jobid ('001') will wrap
* around when it gets to '999', we also assume that '9xx' jobs are
* older than '0xx' jobs.
*/
if ((qe1->job_cfname[3] == '9') && (qe2->job_cfname[3] == '0'))
return (-1);
if ((qe1->job_cfname[3] == '0') && (qe2->job_cfname[3] == '9'))
return (1);
return (strcmp(qe1->job_cfname, qe2->job_cfname));
}
/*
* A simple routine to determine the job number for a print job based on
* the name of its control file. The algorithm used here may look odd, but
* the main issue is that all parts of `lpd', `lpc', `lpq' & `lprm' must be
* using the same algorithm, whatever that algorithm may be. If the caller
* provides a non-null value for ''hostpp', then this returns a pointer to
* the start of the hostname (or IP address?) as found in the filename.
*
* Algorithm: The standard `cf' file has the job number start in position 4,
* but some implementations have that as an extra file-sequence letter, and
* start the job number in position 5. The job number is usually three bytes,
* but may be as many as five. Confusing matters still more, some Windows
* print servers will append an IP address to the job number, instead of
* the expected hostname. So, if the job number ends with a '.', then
* assume the correct jobnum value is the first three digits.
*/
int
calc_jobnum(const char *cfname, const char **hostpp)
{
int jnum;
const char *cp, *numstr, *hoststr;
numstr = cfname + 3;
if (!isdigitch(*numstr))
numstr++;
jnum = 0;
for (cp = numstr; (cp < numstr + 5) && isdigitch(*cp); cp++)
jnum = jnum * 10 + (*cp - '0');
hoststr = cp;
/*
* If the filename was built with an IP number instead of a hostname,
* then recalculate using only the first three digits found.
*/
while(isdigitch(*cp))
cp++;
if (*cp == '.') {
jnum = 0;
for (cp = numstr; (cp < numstr + 3) && isdigitch(*cp); cp++)
jnum = jnum * 10 + (*cp - '0');
hoststr = cp;
}
if (hostpp != NULL)
*hostpp = hoststr;
return (jnum);
}
/* sleep n milliseconds */
void
delay(int millisec)
{
struct timeval tdelay;
if (millisec <= 0 || millisec > 10000)
fatal((struct printer *)0, /* fatal() knows how to deal */
"unreasonable delay period (%d)", millisec);
tdelay.tv_sec = millisec / 1000;
tdelay.tv_usec = millisec * 1000 % 1000000;
(void) select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &tdelay);
}
char *
lock_file_name(const struct printer *pp, char *buf, size_t len)
{
static char staticbuf[MAXPATHLEN];
if (buf == 0)
buf = staticbuf;
if (len == 0)
len = MAXPATHLEN;
if (pp->lock_file[0] == '/')
strlcpy(buf, pp->lock_file, len);
else
snprintf(buf, len, "%s/%s", pp->spool_dir, pp->lock_file);
return buf;
}
char *
status_file_name(const struct printer *pp, char *buf, size_t len)
{
static char staticbuf[MAXPATHLEN];
if (buf == 0)
buf = staticbuf;
if (len == 0)
len = MAXPATHLEN;
if (pp->status_file[0] == '/')
strlcpy(buf, pp->status_file, len);
else
snprintf(buf, len, "%s/%s", pp->spool_dir, pp->status_file);
return buf;
}
/*
* Routine to change operational state of a print queue. The operational
* state is indicated by the access bits on the lock file for the queue.
* At present, this is only called from various routines in lpc/cmds.c.
*
* XXX - Note that this works by changing access-bits on the
* file, and you can only do that if you are the owner of
* the file, or root. Thus, this won't really work for
* userids in the "LPR_OPER" group, unless lpc is running
* setuid to root (or maybe setuid to daemon).
* Generally lpc is installed setgid to daemon, but does
* not run setuid.
*/
int
set_qstate(int action, const char *lfname)
{
struct stat stbuf;
mode_t chgbits, newbits, oldmask;
const char *failmsg, *okmsg;
static const char *nomsg = "no state msg";
int chres, errsav, fd, res, statres;
/*
* Find what the current access-bits are.
*/
memset(&stbuf, 0, sizeof(stbuf));
PRIV_START
statres = stat(lfname, &stbuf);
errsav = errno;
PRIV_END
if ((statres < 0) && (errsav != ENOENT)) {
printf("\tcannot stat() lock file\n");
return (SQS_STATFAIL);
/* NOTREACHED */
}
/*
* Determine which bit(s) should change for the requested action.
*/
chgbits = stbuf.st_mode;
newbits = LOCK_FILE_MODE;
okmsg = NULL;
failmsg = NULL;
if (action & SQS_QCHANGED) {
chgbits |= LFM_RESET_QUE;
newbits |= LFM_RESET_QUE;
/* The okmsg is not actually printed for this case. */
okmsg = nomsg;
failmsg = "set queue-changed";
}
if (action & SQS_DISABLEQ) {
chgbits |= LFM_QUEUE_DIS;
newbits |= LFM_QUEUE_DIS;
okmsg = "queuing disabled";
failmsg = "disable queuing";
}
if (action & SQS_STOPP) {
chgbits |= LFM_PRINT_DIS;
newbits |= LFM_PRINT_DIS;
okmsg = "printing disabled";
failmsg = "disable printing";
if (action & SQS_DISABLEQ) {
okmsg = "printer and queuing disabled";
failmsg = "disable queuing and printing";
}
}
if (action & SQS_ENABLEQ) {
chgbits &= ~LFM_QUEUE_DIS;
newbits &= ~LFM_QUEUE_DIS;
okmsg = "queuing enabled";
failmsg = "enable queuing";
}
if (action & SQS_STARTP) {
chgbits &= ~LFM_PRINT_DIS;
newbits &= ~LFM_PRINT_DIS;
okmsg = "printing enabled";
failmsg = "enable printing";
}
if (okmsg == NULL) {
/* This routine was called with an invalid action. */
printf("\t<error in set_qstate!>\n");
return (SQS_PARMERR);
/* NOTREACHED */
}
res = 0;
if (statres >= 0) {
/* The file already exists, so change the access. */
PRIV_START
chres = chmod(lfname, chgbits);
errsav = errno;
PRIV_END
res = SQS_CHGOK;
if (chres < 0)
res = SQS_CHGFAIL;
} else if (newbits == LOCK_FILE_MODE) {
/*
* The file does not exist, but the state requested is
* the same as the default state when no file exists.
* Thus, there is no need to create the file.
*/
res = SQS_SKIPCREOK;
} else {
/*
* The file did not exist, so create it with the
* appropriate access bits for the requested action.
* Push a new umask around that create, to make sure
* all the read/write bits are set as desired.
*/
oldmask = umask(S_IWOTH);
PRIV_START
fd = open(lfname, O_WRONLY|O_CREAT, newbits);
errsav = errno;
PRIV_END
umask(oldmask);
res = SQS_CREFAIL;
if (fd >= 0) {
res = SQS_CREOK;
close(fd);
}
}
switch (res) {
case SQS_CHGOK:
case SQS_CREOK:
case SQS_SKIPCREOK:
if (okmsg != nomsg)
printf("\t%s\n", okmsg);
break;
case SQS_CREFAIL:
printf("\tcannot create lock file: %s\n",
strerror(errsav));
break;
default:
printf("\tcannot %s: %s\n", failmsg, strerror(errsav));
break;
}
return (res);
}
/* routine to get a current timestamp, optionally in a standard-fmt string */
void
lpd_gettime(struct timespec *tsp, char *strp, size_t strsize)
{
struct timespec local_ts;
struct timeval btime;
char tempstr[TIMESTR_SIZE];
#ifdef STRFTIME_WRONG_z
char *destp;
#endif
if (tsp == NULL)
tsp = &local_ts;
/* some platforms have a routine called clock_gettime, but the
* routine does nothing but return "not implemented". */
memset(tsp, 0, sizeof(struct timespec));
if (clock_gettime(CLOCK_REALTIME, tsp)) {
/* nanosec-aware rtn failed, fall back to microsec-aware rtn */
memset(tsp, 0, sizeof(struct timespec));
gettimeofday(&btime, NULL);
tsp->tv_sec = btime.tv_sec;
tsp->tv_nsec = btime.tv_usec * 1000;
}
/* caller may not need a character-ized version */
if ((strp == NULL) || (strsize < 1))
return;
strftime(tempstr, TIMESTR_SIZE, LPD_TIMESTAMP_PATTERN,
localtime(&tsp->tv_sec));
/*
* This check is for implementations of strftime which treat %z
* (timezone as [+-]hhmm ) like %Z (timezone as characters), or
* completely ignore %z. This section is not needed on freebsd.
* I'm not sure this is completely right, but it should work OK
* for EST and EDT...
*/
#ifdef STRFTIME_WRONG_z
destp = strrchr(tempstr, ':');
if (destp != NULL) {
destp += 3;
if ((*destp != '+') && (*destp != '-')) {
char savday[6];
int tzmin = timezone / 60;
int tzhr = tzmin / 60;
if (daylight)
tzhr--;
strcpy(savday, destp + strlen(destp) - 4);
snprintf(destp, (destp - tempstr), "%+03d%02d",
(-1*tzhr), tzmin % 60);
strcat(destp, savday);
}
}
#endif
if (strsize > TIMESTR_SIZE) {
strsize = TIMESTR_SIZE;
strp[TIMESTR_SIZE+1] = '\0';
}
strlcpy(strp, tempstr, strsize);
}
/* routines for writing transfer-statistic records */
void
trstat_init(struct printer *pp, const char *fname, int filenum)
{
register const char *srcp;
register char *destp, *endp;
/*
* Figure out the job id of this file. The filename should be
* 'cf', 'df', or maybe 'tf', followed by a letter (or sometimes
* two), followed by the jobnum, followed by a hostname.
* The jobnum is usually 3 digits, but might be as many as 5.
* Note that some care has to be taken parsing this, as the
* filename could be coming from a remote-host, and thus might
* not look anything like what is expected...
*/
memset(pp->jobnum, 0, sizeof(pp->jobnum));
pp->jobnum[0] = '0';
srcp = strchr(fname, '/');
if (srcp == NULL)
srcp = fname;
destp = &(pp->jobnum[0]);
endp = destp + 5;
while (*srcp != '\0' && (*srcp < '0' || *srcp > '9'))
srcp++;
while (*srcp >= '0' && *srcp <= '9' && destp < endp)
*(destp++) = *(srcp++);
/* get the starting time in both numeric and string formats, and
* save those away along with the file-number */
pp->jobdfnum = filenum;
lpd_gettime(&pp->tr_start, pp->tr_timestr, (size_t)TIMESTR_SIZE);
return;
}
void
trstat_write(struct printer *pp, tr_sendrecv sendrecv, size_t bytecnt,
const char *userid, const char *otherhost, const char *orighost)
{
#define STATLINE_SIZE 1024
double trtime;
size_t remspace;
int statfile;
char thishost[MAXHOSTNAMELEN], statline[STATLINE_SIZE];
char *eostat;
const char *lprhost, *recvdev, *recvhost, *rectype;
const char *sendhost, *statfname;
#define UPD_EOSTAT(xStr) do { \
eostat = strchr(xStr, '\0'); \
remspace = eostat - xStr; \
} while(0)
lpd_gettime(&pp->tr_done, NULL, (size_t)0);
trtime = DIFFTIME_TS(pp->tr_done, pp->tr_start);
gethostname(thishost, sizeof(thishost));
lprhost = sendhost = recvhost = recvdev = NULL;
switch (sendrecv) {
case TR_SENDING:
rectype = "send";
statfname = pp->stat_send;
sendhost = thishost;
recvhost = otherhost;
break;
case TR_RECVING:
rectype = "recv";
statfname = pp->stat_recv;
sendhost = otherhost;
recvhost = thishost;
break;
case TR_PRINTING:
/*
* This case is for copying to a device (presumably local,
* though filters using things like 'net/CAP' can confuse
* this assumption...).
*/
rectype = "prnt";
statfname = pp->stat_send;
sendhost = thishost;
recvdev = _PATH_DEFDEVLP;
if (pp->lp) recvdev = pp->lp;
break;
default:
/* internal error... should we syslog/printf an error? */
return;
}
if (statfname == NULL)
return;
/*
* the original-host and userid are found out by reading thru the
* cf (control-file) for the job. Unfortunately, on incoming jobs
* the df's (data-files) are sent before the matching cf, so the
* orighost & userid are generally not-available for incoming jobs.
*
* (it would be nice to create a work-around for that..)
*/
if (orighost && (*orighost != '\0'))
lprhost = orighost;
else
lprhost = ".na.";
if (*userid == '\0')
userid = NULL;
/*
* Format of statline.
* Some of the keywords listed here are not implemented here, but
* they are listed to reserve the meaning for a given keyword.
* Fields are separated by a blank. The fields in statline are:
* <tstamp> - time the transfer started
* <ptrqueue> - name of the printer queue (the short-name...)
* <hname> - hostname the file originally came from (the
* 'lpr host'), if known, or "_na_" if not known.
* <xxx> - id of job from that host (generally three digits)
* <n> - file count (# of file within job)
* <rectype> - 4-byte field indicating the type of transfer
* statistics record. "send" means it's from the
* host sending a datafile, "recv" means it's from
* a host as it receives a datafile.
* user=<userid> - user who sent the job (if known)
* secs=<n> - seconds it took to transfer the file
* bytes=<n> - number of bytes transfered (ie, "bytecount")
* bps=<n.n>e<n> - Bytes/sec (if the transfer was "big enough"
* for this to be useful)
* ! top=<str> - type of printer (if the type is defined in
* printcap, and if this statline is for sending
* a file to that ptr)
* ! qls=<n> - queue-length at start of send/print-ing a job
* ! qle=<n> - queue-length at end of send/print-ing a job
* sip=<addr> - IP address of sending host, only included when
* receiving a job.
* shost=<hname> - sending host (if that does != the original host)
* rhost=<hname> - hostname receiving the file (ie, "destination")
* rdev=<dev> - device receiving the file, when the file is being
* send to a device instead of a remote host.
*
* Note: A single print job may be transferred multiple times. The
* original 'lpr' occurs on one host, and that original host might
* send to some interim host (or print server). That interim host
* might turn around and send the job to yet another host (most likely
* the real printer). The 'shost=' parameter is only included if the
* sending host for this particular transfer is NOT the same as the
* host which did the original 'lpr'.
*
* Many values have 'something=' tags before them, because they are
* in some sense "optional", or their order may vary. "Optional" may
* mean in the sense that different SITES might choose to have other
* fields in the record, or that some fields are only included under
* some circumstances. Programs processing these records should not
* assume the order or existence of any of these keyword fields.
*/
snprintf(statline, STATLINE_SIZE, "%s %s %s %s %03ld %s",
pp->tr_timestr, pp->printer, lprhost, pp->jobnum,
pp->jobdfnum, rectype);
UPD_EOSTAT(statline);
if (userid != NULL) {
snprintf(eostat, remspace, " user=%s", userid);
UPD_EOSTAT(statline);
}
snprintf(eostat, remspace, " secs=%#.2f bytes=%lu", trtime,
(unsigned long)bytecnt);
UPD_EOSTAT(statline);
/*
* The bps field duplicates info from bytes and secs, so do
* not bother to include it for very small files.
*/
if ((bytecnt > 25000) && (trtime > 1.1)) {
snprintf(eostat, remspace, " bps=%#.2e",
((double)bytecnt/trtime));
UPD_EOSTAT(statline);
}
if (sendrecv == TR_RECVING) {
if (remspace > 5+strlen(from_ip) ) {
snprintf(eostat, remspace, " sip=%s", from_ip);
UPD_EOSTAT(statline);
}
}
if (0 != strcmp(lprhost, sendhost)) {
if (remspace > 7+strlen(sendhost) ) {
snprintf(eostat, remspace, " shost=%s", sendhost);
UPD_EOSTAT(statline);
}
}
if (recvhost) {
if (remspace > 7+strlen(recvhost) ) {
snprintf(eostat, remspace, " rhost=%s", recvhost);
UPD_EOSTAT(statline);
}
}
if (recvdev) {
if (remspace > 6+strlen(recvdev) ) {
snprintf(eostat, remspace, " rdev=%s", recvdev);
UPD_EOSTAT(statline);
}
}
if (remspace > 1) {
strcpy(eostat, "\n");
} else {
/* probably should back up to just before the final " x=".. */
strcpy(statline+STATLINE_SIZE-2, "\n");
}
statfile = open(statfname, O_WRONLY|O_APPEND, 0664);
if (statfile < 0) {
/* statfile was given, but we can't open it. should we
* syslog/printf this as an error? */
return;
}
write(statfile, statline, strlen(statline));
close(statfile);
return;
#undef UPD_EOSTAT
}
#include <stdarg.h>
void
fatal(const struct printer *pp, const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
/* this error message is being sent to the 'from_host' */
if (from_host != local_host)
(void)printf("%s: ", local_host);
(void)printf("%s: ", progname);
if (pp && pp->printer)
(void)printf("%s: ", pp->printer);
(void)vprintf(msg, ap);
va_end(ap);
(void)putchar('\n');
exit(1);
}
/*
* Close all file descriptors from START on up.
*/
void
closeallfds(int start)
{
int stop;
if (USE_CLOSEFROM) /* The faster, modern solution */
closefrom(start);
else {
/* This older logic can be pretty awful on some OS's. The
* getdtablesize() might return ``infinity'', and then this
* will waste a lot of time closing file descriptors which
* had never been open()-ed. */
stop = getdtablesize();
for (; start < stop; start++)
close(start);
}
}