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tape.c revision 1.13
      1  1.13    lukem /*	$NetBSD: tape.c,v 1.13 1997/09/15 12:42:55 lukem Exp $	*/
      2   1.6      cgd 
      3   1.1      cgd /*-
      4   1.3  mycroft  * Copyright (c) 1980, 1991, 1993
      5   1.3  mycroft  *	The Regents of the University of California.  All rights reserved.
      6   1.1      cgd  *
      7   1.1      cgd  * Redistribution and use in source and binary forms, with or without
      8   1.1      cgd  * modification, are permitted provided that the following conditions
      9   1.1      cgd  * are met:
     10   1.1      cgd  * 1. Redistributions of source code must retain the above copyright
     11   1.1      cgd  *    notice, this list of conditions and the following disclaimer.
     12   1.1      cgd  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1      cgd  *    notice, this list of conditions and the following disclaimer in the
     14   1.1      cgd  *    documentation and/or other materials provided with the distribution.
     15   1.1      cgd  * 3. All advertising materials mentioning features or use of this software
     16   1.1      cgd  *    must display the following acknowledgement:
     17   1.1      cgd  *	This product includes software developed by the University of
     18   1.1      cgd  *	California, Berkeley and its contributors.
     19   1.1      cgd  * 4. Neither the name of the University nor the names of its contributors
     20   1.1      cgd  *    may be used to endorse or promote products derived from this software
     21   1.1      cgd  *    without specific prior written permission.
     22   1.1      cgd  *
     23   1.1      cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24   1.1      cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25   1.1      cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26   1.1      cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27   1.1      cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28   1.1      cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29   1.1      cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30   1.1      cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31   1.1      cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32   1.1      cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33   1.1      cgd  * SUCH DAMAGE.
     34   1.1      cgd  */
     35   1.1      cgd 
     36  1.12    lukem #include <sys/cdefs.h>
     37   1.1      cgd #ifndef lint
     38   1.6      cgd #if 0
     39   1.6      cgd static char sccsid[] = "@(#)tape.c	8.2 (Berkeley) 3/17/94";
     40   1.6      cgd #else
     41  1.13    lukem __RCSID("$NetBSD: tape.c,v 1.13 1997/09/15 12:42:55 lukem Exp $");
     42   1.6      cgd #endif
     43   1.1      cgd #endif /* not lint */
     44   1.1      cgd 
     45   1.3  mycroft #include <sys/param.h>
     46   1.3  mycroft #include <sys/socket.h>
     47   1.3  mycroft #include <sys/time.h>
     48   1.3  mycroft #include <sys/wait.h>
     49   1.1      cgd #ifdef sunos
     50   1.3  mycroft #include <sys/vnode.h>
     51   1.3  mycroft 
     52   1.1      cgd #include <ufs/fs.h>
     53   1.3  mycroft #include <ufs/inode.h>
     54   1.1      cgd #else
     55   1.3  mycroft #include <ufs/ffs/fs.h>
     56   1.3  mycroft #include <ufs/ufs/dinode.h>
     57   1.1      cgd #endif
     58   1.3  mycroft 
     59   1.1      cgd #include <protocols/dumprestore.h>
     60   1.3  mycroft 
     61   1.1      cgd #include <errno.h>
     62   1.3  mycroft #include <fcntl.h>
     63   1.1      cgd #include <setjmp.h>
     64   1.3  mycroft #include <signal.h>
     65   1.3  mycroft #include <stdio.h>
     66   1.1      cgd #ifdef __STDC__
     67   1.1      cgd #include <stdlib.h>
     68   1.1      cgd #include <string.h>
     69   1.8    lukem #include <time.h>
     70   1.3  mycroft #include <unistd.h>
     71   1.3  mycroft #else
     72   1.3  mycroft int	write(), read();
     73   1.1      cgd #endif
     74   1.3  mycroft 
     75   1.1      cgd #include "dump.h"
     76   1.1      cgd #include "pathnames.h"
     77   1.1      cgd 
     78   1.1      cgd int	writesize;		/* size of malloc()ed buffer for tape */
     79   1.1      cgd long	lastspclrec = -1;	/* tape block number of last written header */
     80   1.1      cgd int	trecno = 0;		/* next record to write in current block */
     81   1.1      cgd extern	long blocksperfile;	/* number of blocks per output file */
     82   1.1      cgd long	blocksthisvol;		/* number of blocks on current output file */
     83   1.1      cgd extern	int ntrec;		/* blocking factor on tape */
     84   1.1      cgd extern	int cartridge;
     85   1.1      cgd extern	char *host;
     86   1.1      cgd char	*nexttape;
     87   1.3  mycroft 
     88  1.12    lukem static	ssize_t atomic_read __P((int, char *, int));
     89  1.12    lukem static	ssize_t atomic_write __P((int, char *, int));
     90   1.3  mycroft static	void doslave __P((int, int));
     91   1.3  mycroft static	void enslave __P((void));
     92   1.3  mycroft static	void flushtape __P((void));
     93   1.3  mycroft static	void killall __P((void));
     94  1.12    lukem static	void proceed __P((int));
     95   1.3  mycroft static	void rollforward __P((void));
     96  1.12    lukem static	void sigpipe __P((int));
     97  1.12    lukem static	void tperror __P((int));
     98   1.1      cgd 
     99   1.1      cgd /*
    100   1.1      cgd  * Concurrent dump mods (Caltech) - disk block reading and tape writing
    101   1.1      cgd  * are exported to several slave processes.  While one slave writes the
    102   1.1      cgd  * tape, the others read disk blocks; they pass control of the tape in
    103   1.1      cgd  * a ring via signals. The parent process traverses the filesystem and
    104   1.1      cgd  * sends writeheader()'s and lists of daddr's to the slaves via pipes.
    105   1.1      cgd  * The following structure defines the instruction packets sent to slaves.
    106   1.1      cgd  */
    107   1.1      cgd struct req {
    108   1.1      cgd 	daddr_t dblk;
    109   1.1      cgd 	int count;
    110   1.1      cgd };
    111   1.1      cgd int reqsiz;
    112   1.1      cgd 
    113   1.1      cgd #define SLAVES 3		/* 1 slave writing, 1 reading, 1 for slack */
    114   1.1      cgd struct slave {
    115   1.1      cgd 	int tapea;		/* header number at start of this chunk */
    116   1.1      cgd 	int count;		/* count to next header (used for TS_TAPE */
    117   1.1      cgd 				/* after EOT) */
    118   1.1      cgd 	int inode;		/* inode that we are currently dealing with */
    119   1.1      cgd 	int fd;			/* FD for this slave */
    120   1.1      cgd 	int pid;		/* PID for this slave */
    121   1.1      cgd 	int sent;		/* 1 == we've sent this slave requests */
    122   1.1      cgd 	int firstrec;		/* record number of this block */
    123   1.1      cgd 	char (*tblock)[TP_BSIZE]; /* buffer for data blocks */
    124   1.1      cgd 	struct req *req;	/* buffer for requests */
    125   1.1      cgd } slaves[SLAVES+1];
    126   1.1      cgd struct slave *slp;
    127   1.1      cgd 
    128   1.1      cgd char	(*nextblock)[TP_BSIZE];
    129   1.1      cgd 
    130   1.8    lukem static time_t tstart_volume;	/* time of volume start */
    131   1.8    lukem static int tapea_volume;	/* value of spcl.c_tapea at volume start */
    132   1.8    lukem 
    133   1.1      cgd int master;		/* pid of master, for sending error signals */
    134   1.1      cgd int tenths;		/* length of tape used per block written */
    135   1.1      cgd static int caught;	/* have we caught the signal to proceed? */
    136   1.1      cgd static int ready;	/* have we reached the lock point without having */
    137   1.1      cgd 			/* received the SIGUSR2 signal from the prev slave? */
    138   1.1      cgd static jmp_buf jmpbuf;	/* where to jump to if we are ready when the */
    139   1.1      cgd 			/* SIGUSR2 arrives from the previous slave */
    140   1.1      cgd 
    141   1.1      cgd int
    142   1.1      cgd alloctape()
    143   1.1      cgd {
    144   1.1      cgd 	int pgoff = getpagesize() - 1;
    145   1.1      cgd 	char *buf;
    146   1.1      cgd 	int i;
    147   1.1      cgd 
    148   1.1      cgd 	writesize = ntrec * TP_BSIZE;
    149   1.1      cgd 	reqsiz = (ntrec + 1) * sizeof(struct req);
    150   1.1      cgd 	/*
    151   1.1      cgd 	 * CDC 92181's and 92185's make 0.8" gaps in 1600-bpi start/stop mode
    152   1.1      cgd 	 * (see DEC TU80 User's Guide).  The shorter gaps of 6250-bpi require
    153   1.1      cgd 	 * repositioning after stopping, i.e, streaming mode, where the gap is
    154   1.1      cgd 	 * variable, 0.30" to 0.45".  The gap is maximal when the tape stops.
    155   1.1      cgd 	 */
    156   1.1      cgd 	if (blocksperfile == 0)
    157   1.1      cgd 		tenths = writesize / density +
    158   1.1      cgd 		    (cartridge ? 16 : density == 625 ? 5 : 8);
    159   1.1      cgd 	/*
    160   1.1      cgd 	 * Allocate tape buffer contiguous with the array of instruction
    161   1.1      cgd 	 * packets, so flushtape() can write them together with one write().
    162   1.1      cgd 	 * Align tape buffer on page boundary to speed up tape write().
    163   1.1      cgd 	 */
    164   1.1      cgd 	for (i = 0; i <= SLAVES; i++) {
    165   1.1      cgd 		buf = (char *)
    166   1.1      cgd 		    malloc((unsigned)(reqsiz + writesize + pgoff + TP_BSIZE));
    167   1.1      cgd 		if (buf == NULL)
    168   1.1      cgd 			return(0);
    169   1.1      cgd 		slaves[i].tblock = (char (*)[TP_BSIZE])
    170   1.1      cgd 		    (((long)&buf[ntrec + 1] + pgoff) &~ pgoff);
    171   1.1      cgd 		slaves[i].req = (struct req *)slaves[i].tblock - ntrec - 1;
    172   1.1      cgd 	}
    173   1.1      cgd 	slp = &slaves[0];
    174   1.1      cgd 	slp->count = 1;
    175   1.1      cgd 	slp->tapea = 0;
    176   1.1      cgd 	slp->firstrec = 0;
    177   1.1      cgd 	nextblock = slp->tblock;
    178   1.1      cgd 	return(1);
    179   1.1      cgd }
    180   1.1      cgd 
    181   1.1      cgd void
    182   1.1      cgd writerec(dp, isspcl)
    183   1.1      cgd 	char *dp;
    184   1.1      cgd 	int isspcl;
    185   1.1      cgd {
    186   1.1      cgd 
    187   1.1      cgd 	slp->req[trecno].dblk = (daddr_t)0;
    188   1.1      cgd 	slp->req[trecno].count = 1;
    189   1.1      cgd 	*(union u_spcl *)(*(nextblock)++) = *(union u_spcl *)dp;
    190   1.1      cgd 	if (isspcl)
    191   1.1      cgd 		lastspclrec = spcl.c_tapea;
    192   1.1      cgd 	trecno++;
    193   1.1      cgd 	spcl.c_tapea++;
    194   1.1      cgd 	if (trecno >= ntrec)
    195   1.1      cgd 		flushtape();
    196   1.1      cgd }
    197   1.1      cgd 
    198   1.1      cgd void
    199   1.1      cgd dumpblock(blkno, size)
    200   1.1      cgd 	daddr_t blkno;
    201   1.1      cgd 	int size;
    202   1.1      cgd {
    203   1.1      cgd 	int avail, tpblks, dblkno;
    204   1.1      cgd 
    205   1.1      cgd 	dblkno = fsbtodb(sblock, blkno);
    206   1.1      cgd 	tpblks = size >> tp_bshift;
    207   1.1      cgd 	while ((avail = MIN(tpblks, ntrec - trecno)) > 0) {
    208   1.1      cgd 		slp->req[trecno].dblk = dblkno;
    209   1.1      cgd 		slp->req[trecno].count = avail;
    210   1.1      cgd 		trecno += avail;
    211   1.1      cgd 		spcl.c_tapea += avail;
    212   1.1      cgd 		if (trecno >= ntrec)
    213   1.1      cgd 			flushtape();
    214   1.1      cgd 		dblkno += avail << (tp_bshift - dev_bshift);
    215   1.1      cgd 		tpblks -= avail;
    216   1.1      cgd 	}
    217   1.1      cgd }
    218   1.1      cgd 
    219   1.1      cgd int	nogripe = 0;
    220   1.1      cgd 
    221  1.12    lukem static void
    222   1.1      cgd tperror(signo)
    223   1.1      cgd 	int signo;
    224   1.1      cgd {
    225   1.1      cgd 
    226   1.1      cgd 	if (pipeout) {
    227   1.1      cgd 		msg("write error on %s\n", tape);
    228   1.1      cgd 		quit("Cannot recover\n");
    229   1.1      cgd 		/* NOTREACHED */
    230   1.1      cgd 	}
    231   1.1      cgd 	msg("write error %d blocks into volume %d\n", blocksthisvol, tapeno);
    232   1.1      cgd 	broadcast("DUMP WRITE ERROR!\n");
    233   1.1      cgd 	if (!query("Do you want to restart?"))
    234   1.1      cgd 		dumpabort(0);
    235   1.1      cgd 	msg("Closing this volume.  Prepare to restart with new media;\n");
    236   1.1      cgd 	msg("this dump volume will be rewritten.\n");
    237   1.1      cgd 	killall();
    238   1.1      cgd 	nogripe = 1;
    239   1.1      cgd 	close_rewind();
    240   1.1      cgd 	Exit(X_REWRITE);
    241   1.1      cgd }
    242   1.1      cgd 
    243  1.12    lukem static void
    244   1.1      cgd sigpipe(signo)
    245   1.1      cgd 	int signo;
    246   1.1      cgd {
    247   1.1      cgd 
    248   1.1      cgd 	quit("Broken pipe\n");
    249   1.1      cgd }
    250   1.1      cgd 
    251   1.8    lukem /*
    252   1.8    lukem  * do_stats --
    253   1.8    lukem  *	Update xferrate stats
    254   1.8    lukem  */
    255   1.8    lukem time_t
    256   1.8    lukem do_stats()
    257   1.8    lukem {
    258   1.8    lukem 	time_t tnow, ttaken;
    259   1.8    lukem 	int blocks;
    260   1.8    lukem 
    261   1.8    lukem 	(void)time(&tnow);
    262   1.8    lukem 	ttaken = tnow - tstart_volume;
    263   1.8    lukem 	blocks = spcl.c_tapea - tapea_volume;
    264   1.8    lukem 	msg("Volume %d completed at: %s", tapeno, ctime(&tnow));
    265   1.8    lukem 	if (ttaken > 0) {
    266   1.8    lukem 		msg("Volume %d took %d:%02d:%02d\n", tapeno,
    267   1.8    lukem 		    ttaken / 3600, (ttaken % 3600) / 60, ttaken % 60);
    268  1.11    lukem 		msg("Volume %d transfer rate: %ld KB/s\n", tapeno,
    269   1.8    lukem 		    blocks / ttaken);
    270   1.8    lukem 		xferrate += blocks / ttaken;
    271   1.8    lukem 	}
    272   1.8    lukem 	return(tnow);
    273   1.8    lukem }
    274   1.8    lukem 
    275  1.11    lukem /*
    276  1.11    lukem  * statussig --
    277  1.11    lukem  *	information message upon receipt of SIGINFO
    278  1.11    lukem  *	(derived from optr.c::timeest())
    279  1.11    lukem  */
    280  1.11    lukem void
    281  1.11    lukem statussig(notused)
    282  1.11    lukem 	int notused;
    283  1.11    lukem {
    284  1.11    lukem 	time_t	tnow, deltat;
    285  1.11    lukem 	char	msgbuf[128];
    286  1.11    lukem 
    287  1.11    lukem 	if (blockswritten < 500)
    288  1.11    lukem 		return;
    289  1.11    lukem 	(void) time((time_t *) &tnow);
    290  1.11    lukem 	deltat = tstart_writing - tnow + (1.0 * (tnow - tstart_writing))
    291  1.11    lukem 		/ blockswritten * tapesize;
    292  1.11    lukem 	(void)snprintf(msgbuf, sizeof(msgbuf),
    293  1.11    lukem 	    "%3.2f%% done at %ld KB/s, finished in %d:%02d\n",
    294  1.11    lukem 	    (blockswritten * 100.0) / tapesize,
    295  1.11    lukem 	    (spcl.c_tapea - tapea_volume) / (tnow - tstart_volume),
    296  1.11    lukem 	    (int)(deltat / 3600), (int)((deltat % 3600) / 60));
    297  1.11    lukem 	write(STDERR_FILENO, msgbuf, strlen(msgbuf));
    298  1.11    lukem }
    299  1.11    lukem 
    300   1.3  mycroft static void
    301   1.1      cgd flushtape()
    302   1.1      cgd {
    303   1.1      cgd 	int i, blks, got;
    304   1.1      cgd 	long lastfirstrec;
    305   1.1      cgd 
    306   1.1      cgd 	int siz = (char *)nextblock - (char *)slp->req;
    307   1.1      cgd 
    308   1.1      cgd 	slp->req[trecno].count = 0;			/* Sentinel */
    309   1.1      cgd 
    310  1.12    lukem 	if (atomic_write(slp->fd, (char *)slp->req, siz) != siz)
    311   1.1      cgd 		quit("error writing command pipe: %s\n", strerror(errno));
    312   1.1      cgd 	slp->sent = 1; /* we sent a request, read the response later */
    313   1.1      cgd 
    314   1.1      cgd 	lastfirstrec = slp->firstrec;
    315   1.1      cgd 
    316   1.1      cgd 	if (++slp >= &slaves[SLAVES])
    317   1.1      cgd 		slp = &slaves[0];
    318   1.1      cgd 
    319   1.1      cgd 	/* Read results back from next slave */
    320   1.1      cgd 	if (slp->sent) {
    321  1.12    lukem 		if (atomic_read(slp->fd, (char *)&got, sizeof got)
    322   1.1      cgd 		    != sizeof got) {
    323   1.1      cgd 			perror("  DUMP: error reading command pipe in master");
    324   1.1      cgd 			dumpabort(0);
    325   1.1      cgd 		}
    326   1.1      cgd 		slp->sent = 0;
    327   1.1      cgd 
    328   1.1      cgd 		/* Check for end of tape */
    329   1.1      cgd 		if (got < writesize) {
    330   1.1      cgd 			msg("End of tape detected\n");
    331   1.1      cgd 
    332   1.1      cgd 			/*
    333   1.1      cgd 			 * Drain the results, don't care what the values were.
    334   1.1      cgd 			 * If we read them here then trewind won't...
    335   1.1      cgd 			 */
    336   1.1      cgd 			for (i = 0; i < SLAVES; i++) {
    337   1.1      cgd 				if (slaves[i].sent) {
    338  1.12    lukem 					if (atomic_read(slaves[i].fd,
    339   1.1      cgd 					    (char *)&got, sizeof got)
    340   1.1      cgd 					    != sizeof got) {
    341   1.1      cgd 						perror("  DUMP: error reading command pipe in master");
    342   1.1      cgd 						dumpabort(0);
    343   1.1      cgd 					}
    344   1.1      cgd 					slaves[i].sent = 0;
    345   1.1      cgd 				}
    346   1.1      cgd 			}
    347   1.1      cgd 
    348   1.1      cgd 			close_rewind();
    349   1.1      cgd 			rollforward();
    350   1.1      cgd 			return;
    351   1.1      cgd 		}
    352   1.1      cgd 	}
    353   1.1      cgd 
    354   1.1      cgd 	blks = 0;
    355   1.1      cgd 	if (spcl.c_type != TS_END) {
    356   1.1      cgd 		for (i = 0; i < spcl.c_count; i++)
    357   1.1      cgd 			if (spcl.c_addr[i] != 0)
    358   1.1      cgd 				blks++;
    359   1.1      cgd 	}
    360   1.1      cgd 	slp->count = lastspclrec + blks + 1 - spcl.c_tapea;
    361   1.1      cgd 	slp->tapea = spcl.c_tapea;
    362   1.1      cgd 	slp->firstrec = lastfirstrec + ntrec;
    363   1.1      cgd 	slp->inode = curino;
    364   1.1      cgd 	nextblock = slp->tblock;
    365   1.1      cgd 	trecno = 0;
    366   1.1      cgd 	asize += tenths;
    367   1.1      cgd 	blockswritten += ntrec;
    368   1.1      cgd 	blocksthisvol += ntrec;
    369   1.1      cgd 	if (!pipeout && (blocksperfile ?
    370   1.1      cgd 	    (blocksthisvol >= blocksperfile) : (asize > tsize))) {
    371   1.1      cgd 		close_rewind();
    372   1.1      cgd 		startnewtape(0);
    373   1.1      cgd 	}
    374   1.1      cgd 	timeest();
    375   1.1      cgd }
    376   1.1      cgd 
    377   1.1      cgd void
    378   1.1      cgd trewind()
    379   1.1      cgd {
    380   1.1      cgd 	int f;
    381   1.1      cgd 	int got;
    382   1.1      cgd 
    383   1.1      cgd 	for (f = 0; f < SLAVES; f++) {
    384   1.1      cgd 		/*
    385   1.1      cgd 		 * Drain the results, but unlike EOT we DO (or should) care
    386   1.1      cgd 		 * what the return values were, since if we detect EOT after
    387   1.1      cgd 		 * we think we've written the last blocks to the tape anyway,
    388   1.1      cgd 		 * we have to replay those blocks with rollforward.
    389   1.1      cgd 		 *
    390   1.1      cgd 		 * fixme: punt for now.
    391   1.1      cgd 		 */
    392   1.1      cgd 		if (slaves[f].sent) {
    393  1.12    lukem 			if (atomic_read(slaves[f].fd, (char *)&got, sizeof got)
    394   1.1      cgd 			    != sizeof got) {
    395   1.1      cgd 				perror("  DUMP: error reading command pipe in master");
    396   1.1      cgd 				dumpabort(0);
    397   1.1      cgd 			}
    398   1.1      cgd 			slaves[f].sent = 0;
    399   1.1      cgd 			if (got != writesize) {
    400   1.1      cgd 				msg("EOT detected in last 2 tape records!\n");
    401   1.1      cgd 				msg("Use a longer tape, decrease the size estimate\n");
    402   1.1      cgd 				quit("or use no size estimate at all.\n");
    403   1.1      cgd 			}
    404   1.1      cgd 		}
    405   1.1      cgd 		(void) close(slaves[f].fd);
    406   1.1      cgd 	}
    407   1.1      cgd 	while (wait((int *)NULL) >= 0)	/* wait for any signals from slaves */
    408   1.1      cgd 		/* void */;
    409   1.1      cgd 
    410   1.1      cgd 	if (pipeout)
    411   1.1      cgd 		return;
    412   1.1      cgd 
    413   1.1      cgd 	msg("Closing %s\n", tape);
    414   1.1      cgd 
    415   1.1      cgd #ifdef RDUMP
    416   1.1      cgd 	if (host) {
    417   1.1      cgd 		rmtclose();
    418   1.1      cgd 		while (rmtopen(tape, 0) < 0)
    419   1.1      cgd 			sleep(10);
    420   1.1      cgd 		rmtclose();
    421   1.1      cgd 		return;
    422   1.1      cgd 	}
    423   1.1      cgd #endif
    424   1.1      cgd 	(void) close(tapefd);
    425   1.1      cgd 	while ((f = open(tape, 0)) < 0)
    426   1.1      cgd 		sleep (10);
    427   1.1      cgd 	(void) close(f);
    428   1.1      cgd }
    429   1.1      cgd 
    430   1.1      cgd void
    431   1.1      cgd close_rewind()
    432   1.1      cgd {
    433   1.1      cgd 	trewind();
    434   1.8    lukem 	(void)do_stats();
    435   1.1      cgd 	if (nexttape)
    436   1.1      cgd 		return;
    437   1.1      cgd 	if (!nogripe) {
    438   1.1      cgd 		msg("Change Volumes: Mount volume #%d\n", tapeno+1);
    439   1.1      cgd 		broadcast("CHANGE DUMP VOLUMES!\7\7\n");
    440   1.1      cgd 	}
    441   1.1      cgd 	while (!query("Is the new volume mounted and ready to go?"))
    442   1.1      cgd 		if (query("Do you want to abort?")) {
    443   1.1      cgd 			dumpabort(0);
    444   1.1      cgd 			/*NOTREACHED*/
    445   1.1      cgd 		}
    446   1.1      cgd }
    447   1.1      cgd 
    448   1.1      cgd void
    449   1.1      cgd rollforward()
    450   1.1      cgd {
    451   1.9    lukem 	struct req *p, *q, *prev;
    452   1.9    lukem 	struct slave *tslp;
    453   1.1      cgd 	int i, size, savedtapea, got;
    454   1.1      cgd 	union u_spcl *ntb, *otb;
    455   1.1      cgd 	tslp = &slaves[SLAVES];
    456   1.1      cgd 	ntb = (union u_spcl *)tslp->tblock[1];
    457   1.1      cgd 
    458   1.1      cgd 	/*
    459   1.1      cgd 	 * Each of the N slaves should have requests that need to
    460   1.1      cgd 	 * be replayed on the next tape.  Use the extra slave buffers
    461   1.1      cgd 	 * (slaves[SLAVES]) to construct request lists to be sent to
    462   1.1      cgd 	 * each slave in turn.
    463   1.1      cgd 	 */
    464   1.1      cgd 	for (i = 0; i < SLAVES; i++) {
    465   1.1      cgd 		q = &tslp->req[1];
    466   1.1      cgd 		otb = (union u_spcl *)slp->tblock;
    467   1.1      cgd 
    468   1.1      cgd 		/*
    469   1.1      cgd 		 * For each request in the current slave, copy it to tslp.
    470   1.1      cgd 		 */
    471   1.1      cgd 
    472   1.3  mycroft 		prev = NULL;
    473   1.1      cgd 		for (p = slp->req; p->count > 0; p += p->count) {
    474   1.1      cgd 			*q = *p;
    475   1.1      cgd 			if (p->dblk == 0)
    476   1.1      cgd 				*ntb++ = *otb++; /* copy the datablock also */
    477   1.1      cgd 			prev = q;
    478   1.1      cgd 			q += q->count;
    479   1.1      cgd 		}
    480   1.3  mycroft 		if (prev == NULL)
    481   1.3  mycroft 			quit("rollforward: protocol botch");
    482   1.1      cgd 		if (prev->dblk != 0)
    483   1.1      cgd 			prev->count -= 1;
    484   1.1      cgd 		else
    485   1.1      cgd 			ntb--;
    486   1.1      cgd 		q -= 1;
    487   1.1      cgd 		q->count = 0;
    488   1.1      cgd 		q = &tslp->req[0];
    489   1.1      cgd 		if (i == 0) {
    490   1.1      cgd 			q->dblk = 0;
    491   1.1      cgd 			q->count = 1;
    492   1.1      cgd 			trecno = 0;
    493   1.1      cgd 			nextblock = tslp->tblock;
    494   1.1      cgd 			savedtapea = spcl.c_tapea;
    495   1.1      cgd 			spcl.c_tapea = slp->tapea;
    496   1.1      cgd 			startnewtape(0);
    497   1.1      cgd 			spcl.c_tapea = savedtapea;
    498   1.1      cgd 			lastspclrec = savedtapea - 1;
    499   1.1      cgd 		}
    500   1.1      cgd 		size = (char *)ntb - (char *)q;
    501  1.12    lukem 		if (atomic_write(slp->fd, (char *)q, size) != size) {
    502   1.1      cgd 			perror("  DUMP: error writing command pipe");
    503   1.1      cgd 			dumpabort(0);
    504   1.1      cgd 		}
    505   1.1      cgd 		slp->sent = 1;
    506   1.1      cgd 		if (++slp >= &slaves[SLAVES])
    507   1.1      cgd 			slp = &slaves[0];
    508   1.1      cgd 
    509   1.1      cgd 		q->count = 1;
    510   1.1      cgd 
    511   1.1      cgd 		if (prev->dblk != 0) {
    512   1.1      cgd 			/*
    513   1.1      cgd 			 * If the last one was a disk block, make the
    514   1.1      cgd 			 * first of this one be the last bit of that disk
    515   1.1      cgd 			 * block...
    516   1.1      cgd 			 */
    517   1.1      cgd 			q->dblk = prev->dblk +
    518   1.1      cgd 				prev->count * (TP_BSIZE / DEV_BSIZE);
    519   1.1      cgd 			ntb = (union u_spcl *)tslp->tblock;
    520   1.1      cgd 		} else {
    521   1.1      cgd 			/*
    522   1.1      cgd 			 * It wasn't a disk block.  Copy the data to its
    523   1.1      cgd 			 * new location in the buffer.
    524   1.1      cgd 			 */
    525   1.1      cgd 			q->dblk = 0;
    526   1.1      cgd 			*((union u_spcl *)tslp->tblock) = *ntb;
    527   1.1      cgd 			ntb = (union u_spcl *)tslp->tblock[1];
    528   1.1      cgd 		}
    529   1.1      cgd 	}
    530   1.1      cgd 	slp->req[0] = *q;
    531   1.1      cgd 	nextblock = slp->tblock;
    532   1.1      cgd 	if (q->dblk == 0)
    533   1.1      cgd 		nextblock++;
    534   1.1      cgd 	trecno = 1;
    535   1.1      cgd 
    536   1.1      cgd 	/*
    537   1.1      cgd 	 * Clear the first slaves' response.  One hopes that it
    538   1.1      cgd 	 * worked ok, otherwise the tape is much too short!
    539   1.1      cgd 	 */
    540   1.1      cgd 	if (slp->sent) {
    541  1.12    lukem 		if (atomic_read(slp->fd, (char *)&got, sizeof got)
    542   1.1      cgd 		    != sizeof got) {
    543   1.1      cgd 			perror("  DUMP: error reading command pipe in master");
    544   1.1      cgd 			dumpabort(0);
    545   1.1      cgd 		}
    546   1.1      cgd 		slp->sent = 0;
    547   1.1      cgd 
    548   1.1      cgd 		if (got != writesize) {
    549   1.1      cgd 			quit("EOT detected at start of the tape!\n");
    550   1.1      cgd 		}
    551   1.1      cgd 	}
    552   1.1      cgd }
    553   1.1      cgd 
    554   1.1      cgd /*
    555   1.1      cgd  * We implement taking and restoring checkpoints on the tape level.
    556   1.1      cgd  * When each tape is opened, a new process is created by forking; this
    557   1.1      cgd  * saves all of the necessary context in the parent.  The child
    558   1.1      cgd  * continues the dump; the parent waits around, saving the context.
    559   1.1      cgd  * If the child returns X_REWRITE, then it had problems writing that tape;
    560   1.1      cgd  * this causes the parent to fork again, duplicating the context, and
    561   1.1      cgd  * everything continues as if nothing had happened.
    562   1.1      cgd  */
    563   1.1      cgd void
    564   1.1      cgd startnewtape(top)
    565   1.1      cgd 	int top;
    566   1.1      cgd {
    567   1.1      cgd 	int	parentpid;
    568   1.1      cgd 	int	childpid;
    569   1.1      cgd 	int	status;
    570   1.1      cgd 	int	waitpid;
    571   1.1      cgd 	char	*p;
    572   1.1      cgd #ifdef sunos
    573   1.1      cgd 	void	(*interrupt_save)();
    574   1.1      cgd #else
    575   1.1      cgd 	sig_t	interrupt_save;
    576   1.1      cgd #endif
    577   1.1      cgd 
    578   1.1      cgd 	interrupt_save = signal(SIGINT, SIG_IGN);
    579   1.1      cgd 	parentpid = getpid();
    580   1.8    lukem 	tapea_volume = spcl.c_tapea;
    581   1.8    lukem 	(void)time(&tstart_volume);
    582   1.1      cgd 
    583   1.3  mycroft restore_check_point:
    584   1.1      cgd 	(void)signal(SIGINT, interrupt_save);
    585   1.1      cgd 	/*
    586   1.1      cgd 	 *	All signals are inherited...
    587   1.1      cgd 	 */
    588   1.1      cgd 	childpid = fork();
    589   1.1      cgd 	if (childpid < 0) {
    590   1.1      cgd 		msg("Context save fork fails in parent %d\n", parentpid);
    591   1.1      cgd 		Exit(X_ABORT);
    592   1.1      cgd 	}
    593   1.1      cgd 	if (childpid != 0) {
    594   1.1      cgd 		/*
    595   1.1      cgd 		 *	PARENT:
    596   1.1      cgd 		 *	save the context by waiting
    597   1.1      cgd 		 *	until the child doing all of the work returns.
    598   1.1      cgd 		 *	don't catch the interrupt
    599   1.1      cgd 		 */
    600   1.1      cgd 		signal(SIGINT, SIG_IGN);
    601   1.1      cgd #ifdef TDEBUG
    602   1.1      cgd 		msg("Tape: %d; parent process: %d child process %d\n",
    603   1.1      cgd 			tapeno+1, parentpid, childpid);
    604   1.3  mycroft #endif /* TDEBUG */
    605   1.1      cgd 		while ((waitpid = wait(&status)) != childpid)
    606   1.1      cgd 			msg("Parent %d waiting for child %d has another child %d return\n",
    607   1.1      cgd 				parentpid, childpid, waitpid);
    608   1.1      cgd 		if (status & 0xFF) {
    609   1.1      cgd 			msg("Child %d returns LOB status %o\n",
    610   1.1      cgd 				childpid, status&0xFF);
    611   1.1      cgd 		}
    612   1.1      cgd 		status = (status >> 8) & 0xFF;
    613   1.1      cgd #ifdef TDEBUG
    614   1.1      cgd 		switch(status) {
    615   1.1      cgd 			case X_FINOK:
    616   1.1      cgd 				msg("Child %d finishes X_FINOK\n", childpid);
    617   1.1      cgd 				break;
    618   1.1      cgd 			case X_ABORT:
    619   1.1      cgd 				msg("Child %d finishes X_ABORT\n", childpid);
    620   1.1      cgd 				break;
    621   1.1      cgd 			case X_REWRITE:
    622   1.1      cgd 				msg("Child %d finishes X_REWRITE\n", childpid);
    623   1.1      cgd 				break;
    624   1.1      cgd 			default:
    625   1.1      cgd 				msg("Child %d finishes unknown %d\n",
    626   1.1      cgd 					childpid, status);
    627   1.1      cgd 				break;
    628   1.1      cgd 		}
    629   1.3  mycroft #endif /* TDEBUG */
    630   1.1      cgd 		switch(status) {
    631   1.1      cgd 			case X_FINOK:
    632   1.1      cgd 				Exit(X_FINOK);
    633   1.1      cgd 			case X_ABORT:
    634   1.1      cgd 				Exit(X_ABORT);
    635   1.1      cgd 			case X_REWRITE:
    636   1.1      cgd 				goto restore_check_point;
    637   1.1      cgd 			default:
    638   1.1      cgd 				msg("Bad return code from dump: %d\n", status);
    639   1.1      cgd 				Exit(X_ABORT);
    640   1.1      cgd 		}
    641   1.1      cgd 		/*NOTREACHED*/
    642   1.1      cgd 	} else {	/* we are the child; just continue */
    643   1.1      cgd #ifdef TDEBUG
    644   1.1      cgd 		sleep(4);	/* allow time for parent's message to get out */
    645   1.1      cgd 		msg("Child on Tape %d has parent %d, my pid = %d\n",
    646   1.1      cgd 			tapeno+1, parentpid, getpid());
    647   1.3  mycroft #endif /* TDEBUG */
    648   1.1      cgd 		/*
    649  1.10    lukem 		 * If we have a name like "/dev/rst0,/dev/rst1",
    650   1.1      cgd 		 * use the name before the comma first, and save
    651   1.1      cgd 		 * the remaining names for subsequent volumes.
    652   1.1      cgd 		 */
    653   1.1      cgd 		tapeno++;               /* current tape sequence */
    654   1.4  mycroft 		if (nexttape || strchr(tape, ',')) {
    655   1.1      cgd 			if (nexttape && *nexttape)
    656   1.1      cgd 				tape = nexttape;
    657   1.4  mycroft 			if ((p = strchr(tape, ',')) != NULL) {
    658   1.1      cgd 				*p = '\0';
    659   1.1      cgd 				nexttape = p + 1;
    660   1.1      cgd 			} else
    661   1.1      cgd 				nexttape = NULL;
    662   1.1      cgd 			msg("Dumping volume %d on %s\n", tapeno, tape);
    663   1.1      cgd 		}
    664   1.1      cgd #ifdef RDUMP
    665   1.1      cgd 		while ((tapefd = (host ? rmtopen(tape, 2) :
    666   1.1      cgd 			pipeout ? 1 : open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
    667   1.1      cgd #else
    668   1.1      cgd 		while ((tapefd = (pipeout ? 1 :
    669   1.1      cgd 				  open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
    670   1.1      cgd #endif
    671   1.1      cgd 		    {
    672   1.1      cgd 			msg("Cannot open output \"%s\".\n", tape);
    673   1.1      cgd 			if (!query("Do you want to retry the open?"))
    674   1.1      cgd 				dumpabort(0);
    675   1.1      cgd 		}
    676   1.1      cgd 
    677   1.1      cgd 		enslave();  /* Share open tape file descriptor with slaves */
    678   1.1      cgd 
    679   1.1      cgd 		asize = 0;
    680   1.1      cgd 		blocksthisvol = 0;
    681   1.1      cgd 		if (top)
    682   1.1      cgd 			newtape++;		/* new tape signal */
    683   1.1      cgd 		spcl.c_count = slp->count;
    684   1.1      cgd 		/*
    685   1.1      cgd 		 * measure firstrec in TP_BSIZE units since restore doesn't
    686   1.1      cgd 		 * know the correct ntrec value...
    687   1.1      cgd 		 */
    688   1.1      cgd 		spcl.c_firstrec = slp->firstrec;
    689   1.1      cgd 		spcl.c_volume++;
    690   1.1      cgd 		spcl.c_type = TS_TAPE;
    691   1.1      cgd 		spcl.c_flags |= DR_NEWHEADER;
    692   1.1      cgd 		writeheader((ino_t)slp->inode);
    693   1.1      cgd 		spcl.c_flags &=~ DR_NEWHEADER;
    694   1.8    lukem 		msg("Volume %d started at: %s", tapeno, ctime(&tstart_volume));
    695   1.1      cgd 		if (tapeno > 1)
    696   1.1      cgd 			msg("Volume %d begins with blocks from inode %d\n",
    697   1.1      cgd 				tapeno, slp->inode);
    698   1.1      cgd 	}
    699   1.1      cgd }
    700   1.1      cgd 
    701   1.1      cgd void
    702   1.1      cgd dumpabort(signo)
    703   1.1      cgd 	int signo;
    704   1.1      cgd {
    705   1.1      cgd 
    706   1.1      cgd 	if (master != 0 && master != getpid())
    707   1.1      cgd 		/* Signals master to call dumpabort */
    708   1.1      cgd 		(void) kill(master, SIGTERM);
    709   1.1      cgd 	else {
    710   1.1      cgd 		killall();
    711   1.1      cgd 		msg("The ENTIRE dump is aborted.\n");
    712   1.1      cgd 	}
    713   1.2      cgd #ifdef RDUMP
    714   1.2      cgd 	rmtclose();
    715   1.2      cgd #endif
    716   1.1      cgd 	Exit(X_ABORT);
    717   1.1      cgd }
    718   1.1      cgd 
    719  1.13    lukem void
    720   1.1      cgd Exit(status)
    721   1.1      cgd 	int status;
    722   1.1      cgd {
    723   1.1      cgd 
    724   1.1      cgd #ifdef TDEBUG
    725   1.1      cgd 	msg("pid = %d exits with status %d\n", getpid(), status);
    726   1.3  mycroft #endif /* TDEBUG */
    727   1.3  mycroft 	exit(status);
    728   1.1      cgd }
    729   1.1      cgd 
    730   1.1      cgd /*
    731   1.1      cgd  * proceed - handler for SIGUSR2, used to synchronize IO between the slaves.
    732   1.1      cgd  */
    733  1.12    lukem static void
    734   1.1      cgd proceed(signo)
    735   1.1      cgd 	int signo;
    736   1.1      cgd {
    737   1.1      cgd 
    738   1.1      cgd 	if (ready)
    739   1.1      cgd 		longjmp(jmpbuf, 1);
    740   1.1      cgd 	caught++;
    741   1.1      cgd }
    742   1.1      cgd 
    743   1.1      cgd void
    744   1.1      cgd enslave()
    745   1.1      cgd {
    746   1.1      cgd 	int cmd[2];
    747   1.9    lukem 	int i, j;
    748   1.1      cgd 
    749   1.1      cgd 	master = getpid();
    750   1.1      cgd 
    751   1.1      cgd 	signal(SIGTERM, dumpabort);  /* Slave sends SIGTERM on dumpabort() */
    752   1.1      cgd 	signal(SIGPIPE, sigpipe);
    753   1.1      cgd 	signal(SIGUSR1, tperror);    /* Slave sends SIGUSR1 on tape errors */
    754   1.1      cgd 	signal(SIGUSR2, proceed);    /* Slave sends SIGUSR2 to next slave */
    755   1.1      cgd 
    756   1.1      cgd 	for (i = 0; i < SLAVES; i++) {
    757   1.1      cgd 		if (i == slp - &slaves[0]) {
    758   1.1      cgd 			caught = 1;
    759   1.1      cgd 		} else {
    760   1.1      cgd 			caught = 0;
    761   1.1      cgd 		}
    762   1.1      cgd 
    763   1.1      cgd 		if (socketpair(AF_UNIX, SOCK_STREAM, 0, cmd) < 0 ||
    764   1.1      cgd 		    (slaves[i].pid = fork()) < 0)
    765   1.1      cgd 			quit("too many slaves, %d (recompile smaller): %s\n",
    766   1.1      cgd 			    i, strerror(errno));
    767   1.1      cgd 
    768   1.1      cgd 		slaves[i].fd = cmd[1];
    769   1.1      cgd 		slaves[i].sent = 0;
    770   1.1      cgd 		if (slaves[i].pid == 0) { 	    /* Slave starts up here */
    771   1.1      cgd 			for (j = 0; j <= i; j++)
    772   1.1      cgd 			        (void) close(slaves[j].fd);
    773   1.1      cgd 			signal(SIGINT, SIG_IGN);    /* Master handles this */
    774  1.11    lukem 			signal(SIGINFO, SIG_IGN);
    775   1.1      cgd 			doslave(cmd[0], i);
    776   1.1      cgd 			Exit(X_FINOK);
    777   1.1      cgd 		}
    778   1.1      cgd 	}
    779   1.1      cgd 
    780   1.1      cgd 	for (i = 0; i < SLAVES; i++)
    781  1.12    lukem 		(void) atomic_write(slaves[i].fd,
    782   1.1      cgd 			      (char *) &slaves[(i + 1) % SLAVES].pid,
    783   1.1      cgd 		              sizeof slaves[0].pid);
    784   1.1      cgd 
    785   1.1      cgd 	master = 0;
    786   1.1      cgd }
    787   1.1      cgd 
    788   1.1      cgd void
    789   1.1      cgd killall()
    790   1.1      cgd {
    791   1.9    lukem 	int i;
    792   1.1      cgd 
    793   1.1      cgd 	for (i = 0; i < SLAVES; i++)
    794   1.1      cgd 		if (slaves[i].pid > 0)
    795   1.1      cgd 			(void) kill(slaves[i].pid, SIGKILL);
    796   1.1      cgd }
    797   1.1      cgd 
    798   1.1      cgd /*
    799   1.1      cgd  * Synchronization - each process has a lockfile, and shares file
    800   1.1      cgd  * descriptors to the following process's lockfile.  When our write
    801   1.1      cgd  * completes, we release our lock on the following process's lock-
    802   1.1      cgd  * file, allowing the following process to lock it and proceed. We
    803   1.1      cgd  * get the lock back for the next cycle by swapping descriptors.
    804   1.1      cgd  */
    805   1.3  mycroft static void
    806   1.1      cgd doslave(cmd, slave_number)
    807   1.9    lukem 	int cmd;
    808   1.1      cgd         int slave_number;
    809   1.1      cgd {
    810   1.9    lukem 	int nread;
    811   1.1      cgd 	int nextslave, size, wrote, eot_count;
    812   1.7  mycroft 	sigset_t sigset;
    813   1.1      cgd 
    814   1.1      cgd 	/*
    815   1.1      cgd 	 * Need our own seek pointer.
    816   1.1      cgd 	 */
    817   1.1      cgd 	(void) close(diskfd);
    818   1.1      cgd 	if ((diskfd = open(disk, O_RDONLY)) < 0)
    819   1.1      cgd 		quit("slave couldn't reopen disk: %s\n", strerror(errno));
    820   1.1      cgd 
    821   1.1      cgd 	/*
    822   1.1      cgd 	 * Need the pid of the next slave in the loop...
    823   1.1      cgd 	 */
    824  1.12    lukem 	if ((nread = atomic_read(cmd, (char *)&nextslave, sizeof nextslave))
    825   1.1      cgd 	    != sizeof nextslave) {
    826   1.1      cgd 		quit("master/slave protocol botched - didn't get pid of next slave.\n");
    827   1.1      cgd 	}
    828   1.1      cgd 
    829   1.1      cgd 	/*
    830   1.1      cgd 	 * Get list of blocks to dump, read the blocks into tape buffer
    831   1.1      cgd 	 */
    832  1.12    lukem 	while ((nread = atomic_read(cmd, (char *)slp->req, reqsiz)) == reqsiz) {
    833   1.9    lukem 		struct req *p = slp->req;
    834   1.1      cgd 
    835   1.1      cgd 		for (trecno = 0; trecno < ntrec;
    836   1.1      cgd 		     trecno += p->count, p += p->count) {
    837   1.1      cgd 			if (p->dblk) {
    838   1.1      cgd 				bread(p->dblk, slp->tblock[trecno],
    839   1.1      cgd 					p->count * TP_BSIZE);
    840   1.1      cgd 			} else {
    841  1.12    lukem 				if (p->count != 1 || atomic_read(cmd,
    842   1.1      cgd 				    (char *)slp->tblock[trecno],
    843   1.1      cgd 				    TP_BSIZE) != TP_BSIZE)
    844   1.1      cgd 				       quit("master/slave protocol botched.\n");
    845   1.1      cgd 			}
    846   1.1      cgd 		}
    847   1.1      cgd 		if (setjmp(jmpbuf) == 0) {
    848   1.1      cgd 			ready = 1;
    849   1.1      cgd 			if (!caught)
    850   1.1      cgd 				(void) pause();
    851   1.1      cgd 		}
    852   1.1      cgd 		ready = 0;
    853   1.1      cgd 		caught = 0;
    854   1.1      cgd 
    855   1.1      cgd 		/* Try to write the data... */
    856   1.1      cgd 		eot_count = 0;
    857   1.1      cgd 		size = 0;
    858   1.1      cgd 
    859   1.1      cgd 		while (eot_count < 10 && size < writesize) {
    860   1.1      cgd #ifdef RDUMP
    861   1.1      cgd 			if (host)
    862   1.1      cgd 				wrote = rmtwrite(slp->tblock[0]+size,
    863   1.1      cgd 				    writesize-size);
    864   1.1      cgd 			else
    865   1.1      cgd #endif
    866   1.1      cgd 				wrote = write(tapefd, slp->tblock[0]+size,
    867   1.1      cgd 				    writesize-size);
    868   1.1      cgd #ifdef WRITEDEBUG
    869   1.1      cgd 			printf("slave %d wrote %d\n", slave_number, wrote);
    870   1.1      cgd #endif
    871   1.1      cgd 			if (wrote < 0)
    872   1.1      cgd 				break;
    873   1.1      cgd 			if (wrote == 0)
    874   1.1      cgd 				eot_count++;
    875   1.1      cgd 			size += wrote;
    876   1.1      cgd 		}
    877   1.1      cgd 
    878   1.1      cgd #ifdef WRITEDEBUG
    879   1.1      cgd 		if (size != writesize)
    880   1.1      cgd 		 printf("slave %d only wrote %d out of %d bytes and gave up.\n",
    881   1.1      cgd 		     slave_number, size, writesize);
    882   1.1      cgd #endif
    883   1.1      cgd 
    884   1.1      cgd 		if (eot_count > 0)
    885   1.1      cgd 			size = 0;
    886   1.1      cgd 
    887   1.1      cgd 		/*
    888   1.1      cgd 		 * fixme: Pyramids running OSx return ENOSPC
    889   1.1      cgd 		 * at EOT on 1/2 inch drives.
    890   1.1      cgd 		 */
    891   1.1      cgd 		if (size < 0) {
    892   1.1      cgd 			(void) kill(master, SIGUSR1);
    893   1.7  mycroft 			sigemptyset(&sigset);
    894   1.1      cgd 			for (;;)
    895   1.7  mycroft 				sigsuspend(&sigset);
    896   1.1      cgd 		} else {
    897   1.1      cgd 			/*
    898   1.1      cgd 			 * pass size of write back to master
    899   1.1      cgd 			 * (for EOT handling)
    900   1.1      cgd 			 */
    901  1.12    lukem 			(void) atomic_write(cmd, (char *)&size, sizeof size);
    902   1.1      cgd 		}
    903   1.1      cgd 
    904   1.1      cgd 		/*
    905   1.1      cgd 		 * If partial write, don't want next slave to go.
    906   1.1      cgd 		 * Also jolts him awake.
    907   1.1      cgd 		 */
    908   1.1      cgd 		(void) kill(nextslave, SIGUSR2);
    909   1.1      cgd 	}
    910   1.1      cgd 	if (nread != 0)
    911   1.1      cgd 		quit("error reading command pipe: %s\n", strerror(errno));
    912   1.1      cgd }
    913   1.1      cgd 
    914   1.1      cgd /*
    915   1.1      cgd  * Since a read from a pipe may not return all we asked for,
    916   1.1      cgd  * loop until the count is satisfied (or error).
    917   1.1      cgd  */
    918   1.5      cgd static ssize_t
    919  1.12    lukem atomic_read(fd, buf, count)
    920  1.12    lukem 	int fd;
    921  1.12    lukem 	char *buf;
    922  1.12    lukem 	int count;
    923  1.12    lukem {
    924  1.12    lukem 	ssize_t got, need = count;
    925  1.12    lukem 
    926  1.12    lukem 	while ((got = read(fd, buf, need)) > 0 && (need -= got) > 0)
    927  1.12    lukem 		buf += got;
    928  1.12    lukem 	return (got < 0 ? got : count - need);
    929  1.12    lukem }
    930  1.12    lukem 
    931  1.12    lukem /*
    932  1.12    lukem  * Since a write may not write all we ask if we get a signal,
    933  1.12    lukem  * loop until the count is satisfied (or error).
    934  1.12    lukem  */
    935  1.12    lukem static ssize_t
    936  1.12    lukem atomic_write(fd, buf, count)
    937   1.5      cgd 	int fd;
    938   1.1      cgd 	char *buf;
    939   1.3  mycroft 	int count;
    940   1.1      cgd {
    941   1.5      cgd 	ssize_t got, need = count;
    942   1.1      cgd 
    943  1.12    lukem 	while ((got = write(fd, buf, need)) > 0 && (need -= got) > 0)
    944   1.1      cgd 		buf += got;
    945   1.1      cgd 	return (got < 0 ? got : count - need);
    946   1.1      cgd }
    947