text: /*
   * Copyright (c) 1998-2001 Apple Computer, Inc. All rights reserved.
   *
   * @APPLE_LICENSE_HEADER_START@
   *
   * The contents of this file constitute Original Code as defined in and
   * are subject to the Apple Public Source License Version 1.2 (the
   * "License").  You may not use this file except in compliance with the
   * License.  Please obtain a copy of the License at
   * http://www.apple.com/publicsource and read it before using this file.
   *
   * This Original Code and all software distributed under the License are
   * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
   * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
   * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
   * License for the specific language governing rights and limitations
   * under the License.
   *
   * @APPLE_LICENSE_HEADER_END@
   *
   *	File:	fsx.c
   *	Author:	Avadis Tevanian, Jr.
   *
   *	File system exerciser. 
   *
   *	Rewrite and enhancements 1998-2001 Conrad Minshall -- conrad@mac.com
   *
   *	Various features from Joe Sokol, Pat Dirks, and Clark Warner.
   *
   *	Small changes to work under Linux -- davej@suse.de
   *
   *	Sundry porting patches from Guy Harris 12/2001
   *
   *	Checks for mmap last-page zero fill.
   *
   * $FreeBSD: src/tools/regression/fsx/fsx.c,v 1.2 2003/04/23 23:42:23 jkh Exp $
   * $DragonFly: src/tools/regression/fsx/fsx.c,v 1.1 2003/10/11 13:37:14 drhodus Exp $
   *
   */
  
  #include <sys/types.h>
  #include <sys/stat.h>
  #ifdef _UWIN
  # include <sys/param.h>
  # include <limits.h>
  # include <time.h>
  # include <strings.h>
  #endif
  #include <fcntl.h>
  #include <sys/mman.h>
  #ifndef MAP_FILE
  # define MAP_FILE 0
  #endif
  #include <limits.h>
  #include <signal.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  #include <stdarg.h>
  #include <errno.h>
  
  #define NUMPRINTCOLUMNS 32	/* # columns of data to print on each line */
  
  /*
   *	A log entry is an operation and a bunch of arguments.
   */
  
  struct log_entry {
  	int	operation;
  	int	args[3];
  };
  
  #define	LOGSIZE	1000
  
  struct log_entry	oplog[LOGSIZE];	/* the log */
  int			logptr = 0;	/* current position in log */
  int			logcount = 0;	/* total ops */
  
  /*
   *	Define operations
   */
  
  #define	OP_READ		1
  #define OP_WRITE	2
  #define OP_TRUNCATE	3
  #define OP_CLOSEOPEN	4
  #define OP_MAPREAD	5
  #define OP_MAPWRITE	6
  #define OP_SKIPPED	7
  
  int page_size;
  int page_mask;
  
  char	*original_buf;			/* a pointer to the original data */
  char	*good_buf;			/* a pointer to the correct data */
  char	*temp_buf;			/* a pointer to the current data */
  char	*fname;				/* name of our test file */
  int	fd;				/* fd for our test file */
  
  off_t		file_size = 0;
  off_t		biggest = 0;
  char		state[256];
  unsigned long	testcalls = 0;		/* calls to function "test" */
  
  unsigned long	simulatedopcount = 0;	/* -b flag */
  int	closeprob = 0;			/* -c flag */
  int	debug = 0;			/* -d flag */
  unsigned long	debugstart = 0;		/* -D flag */
  unsigned long	maxfilelen = 256 * 1024;	/* -l flag */
  int	sizechecks = 1;			/* -n flag disables them */
  int	maxoplen = 64 * 1024;		/* -o flag */
  int	quiet = 0;			/* -q flag */
  unsigned long progressinterval = 0;	/* -p flag */
  int	readbdy = 1;			/* -r flag */
  int	style = 0;			/* -s flag */
  int	truncbdy = 1;			/* -t flag */
  int	writebdy = 1;			/* -w flag */
  long	monitorstart = -1;		/* -m flag */
  long	monitorend = -1;		/* -m flag */
  int	lite = 0;			/* -L flag */
  long	numops = -1;			/* -N flag */
  int	randomoplen = 1;		/* -O flag disables it */
  int	seed = 1;			/* -S flag */
  int     mapped_writes = 1;	      /* -W flag disables */
  int 	mapped_reads = 1;		/* -R flag disables it */
  int	fsxgoodfd = 0;
  FILE *	fsxlogf = NULL;
  int badoff = -1;
  int closeopen = 0;
  
  
  void
  vwarnc(code, fmt, ap)
  	int code;
  	const char *fmt;
  	va_list ap;
  {
  	fprintf(stderr, "fsx: ");
  	if (fmt != NULL) {
  		vfprintf(stderr, fmt, ap);
  		fprintf(stderr, ": ");
  	}
  	fprintf(stderr, "%s\n", strerror(code));
  }
  
  
  void
  warn(const char * fmt, ...)
  {
  	va_list ap;
  	va_start(ap, fmt);
  	vwarnc(errno, fmt, ap);
  	va_end(ap);
  }
  
  
  void
  prt(char *fmt, ...)
  {
  	va_list args;
  
  	va_start(args, fmt);
  	vfprintf(stdout, fmt, args);
  	if (fsxlogf)
  		vfprintf(fsxlogf, fmt, args);
  	va_end(args);
  }
  
  void
  prterr(char *prefix)
  {
  	prt("%s%s%s\n", prefix, prefix ? ": " : "", strerror(errno));
  }
  
  
  void
  log4(int operation, int arg0, int arg1, int arg2)
  {
  	struct log_entry *le;
  
  	le = &oplog[logptr];
  	le->operation = operation;
  	if (closeopen)
  		le->operation = ~ le->operation;
  	le->args[0] = arg0;
  	le->args[1] = arg1;
  	le->args[2] = arg2;
  	logptr++;
  	logcount++;
  	if (logptr >= LOGSIZE)
  		logptr = 0;
  }
  
  
  void
  logdump(void)
  {
  	int	i, count, down;
  	struct log_entry	*lp;
  
  	prt("LOG DUMP (%d total operations):\n", logcount);
  	if (logcount < LOGSIZE) {
  		i = 0;
  		count = logcount;
  	} else {
  		i = logptr;
  		count = LOGSIZE;
  	}
  	for ( ; count > 0; count--) {
  		int opnum;
  
  		opnum = i+1 + (logcount/LOGSIZE)*LOGSIZE;
  		prt("%d(%d mod 256): ", opnum, opnum%256);
  		lp = &oplog[i];
  		if ((closeopen = lp->operation < 0))
  			lp->operation = ~ lp->operation;
  			
  		switch (lp->operation) {
  		case OP_MAPREAD:
  			prt("MAPREAD\t0x%x thru 0x%x\t(0x%x bytes)",
  			    lp->args[0], lp->args[0] + lp->args[1] - 1,
  			    lp->args[1]);
  			if (badoff >= lp->args[0] && badoff <
  						     lp->args[0] + lp->args[1])
  				prt("\t***RRRR***");
  			break;
  		case OP_MAPWRITE:
  			prt("MAPWRITE 0x%x thru 0x%x\t(0x%x bytes)",
  			    lp->args[0], lp->args[0] + lp->args[1] - 1,
  			    lp->args[1]);
  			if (badoff >= lp->args[0] && badoff <
  						     lp->args[0] + lp->args[1])
  				prt("\t******WWWW");
  			break;
  		case OP_READ:
  			prt("READ\t0x%x thru 0x%x\t(0x%x bytes)",
  			    lp->args[0], lp->args[0] + lp->args[1] - 1,
  			    lp->args[1]);
  			if (badoff >= lp->args[0] &&
  			    badoff < lp->args[0] + lp->args[1])
  				prt("\t***RRRR***");
  			break;
  		case OP_WRITE:
  			prt("WRITE\t0x%x thru 0x%x\t(0x%x bytes)",
  			    lp->args[0], lp->args[0] + lp->args[1] - 1,
  			    lp->args[1]);
  			if (lp->args[0] > lp->args[2])
  				prt(" HOLE");
  			else if (lp->args[0] + lp->args[1] > lp->args[2])
  				prt(" EXTEND");
  			if ((badoff >= lp->args[0] || badoff >=lp->args[2]) &&
  			    badoff < lp->args[0] + lp->args[1])
  				prt("\t***WWWW");
  			break;
  		case OP_TRUNCATE:
  			down = lp->args[0] < lp->args[1];
  			prt("TRUNCATE %s\tfrom 0x%x to 0x%x",
  			    down ? "DOWN" : "UP", lp->args[1], lp->args[0]);
  			if (badoff >= lp->args[!down] &&
  			    badoff < lp->args[!!down])
  				prt("\t******WWWW");
  			break;
  		case OP_SKIPPED:
  			prt("SKIPPED (no operation)");
  			break;
  		default:
  			prt("BOGUS LOG ENTRY (operation code = %d)!",
  			    lp->operation);
  		}
  		if (closeopen)
  			prt("\n\t\tCLOSE/OPEN");
  		prt("\n");
  		i++;
  		if (i == LOGSIZE)
  			i = 0;
  	}
  }
  
  
  void
  save_buffer(char *buffer, off_t bufferlength, int fd)
  {
  	off_t ret;
  	ssize_t byteswritten;
  
  	if (fd <= 0 || bufferlength == 0)
  		return;
  
  	if (bufferlength > SSIZE_MAX) {
  		prt("fsx flaw: overflow in save_buffer\n");
  		exit(67);
  	}
  	if (lite) {
  		off_t size_by_seek = lseek(fd, (off_t)0, SEEK_END);
  		if (size_by_seek == (off_t)-1)
  			prterr("save_buffer: lseek eof");
  		else if (bufferlength > size_by_seek) {
  			warn("save_buffer: .fsxgood file too short... will save 0x%llx bytes instead of 0x%llx\n", (unsigned long long)size_by_seek,
  			     (unsigned long long)bufferlength);
  			bufferlength = size_by_seek;
  		}
  	}
  
  	ret = lseek(fd, (off_t)0, SEEK_SET);
  	if (ret == (off_t)-1)
  		prterr("save_buffer: lseek 0");
  	
  	byteswritten = write(fd, buffer, (size_t)bufferlength);
  	if (byteswritten != bufferlength) {
  		if (byteswritten == -1)
  			prterr("save_buffer write");
  		else
  			warn("save_buffer: short write, 0x%x bytes instead of 0x%llx\n",
  			     (unsigned)byteswritten,
  			     (unsigned long long)bufferlength);
  	}
  }
  
  
  void
  report_failure(int status)
  {
  	logdump();
  	
  	if (fsxgoodfd) {
  		if (good_buf) {
  			save_buffer(good_buf, file_size, fsxgoodfd);
  			prt("Correct content saved for comparison\n");
  			prt("(maybe hexdump \"%s\" vs \"%s.fsxgood\")\n",
  			    fname, fname);
  		}
  		close(fsxgoodfd);
  	}
  	exit(status);
  }
  
  
  #define short_at(cp) ((unsigned short)((*((unsigned char *)(cp)) << 8) | \
  					*(((unsigned char *)(cp)) + 1)))
  
  void
  check_buffers(unsigned offset, unsigned size)
  {
  	unsigned char c, t;
  	unsigned i = 0;
  	unsigned n = 0;
  	unsigned op = 0;
  	unsigned bad = 0;
  
  	if (memcmp(good_buf + offset, temp_buf, size) != 0) {
  		prt("READ BAD DATA: offset = 0x%x, size = 0x%x\n",
  		    offset, size);
  		prt("OFFSET\tGOOD\tBAD\tRANGE\n");
  		while (size > 0) {
  			c = good_buf[offset];
  			t = temp_buf[i];
  			if (c != t) {
  				if (n == 0) {
  					bad = short_at(&temp_buf[i]);
  					prt("0x%5x\t0x%04x\t0x%04x", offset,
  					    short_at(&good_buf[offset]), bad);
  					op = temp_buf[offset & 1 ? i+1 : i];
  				}
  				n++;
  				badoff = offset;
  			}
  			offset++;
  			i++;
  			size--;
  		}
  		if (n) {
  			prt("\t0x%5x\n", n);
  			if (bad)
  				prt("operation# (mod 256) for the bad data may be %u\n", ((unsigned)op & 0xff));
  			else
  				prt("operation# (mod 256) for the bad data unknown, check HOLE and EXTEND ops\n");
  		} else
  			prt("????????????????\n");
  		report_failure(110);
  	}
  }
  
  
  void
  check_size(void)
  {
  	struct stat	statbuf;
  	off_t	size_by_seek;
  
  	if (fstat(fd, &statbuf)) {
  		prterr("check_size: fstat");
  		statbuf.st_size = -1;
  	}
  	size_by_seek = lseek(fd, (off_t)0, SEEK_END);
  	if (file_size != statbuf.st_size || file_size != size_by_seek) {
  		prt("Size error: expected 0x%llx stat 0x%llx seek 0x%llx\n",
  		    (unsigned long long)file_size,
  		    (unsigned long long)statbuf.st_size,
  		    (unsigned long long)size_by_seek);
  		report_failure(120);
  	}
  }
  
  
  void
  check_trunc_hack(void)
  {
  	struct stat statbuf;
  
  	ftruncate(fd, (off_t)0);
  	ftruncate(fd, (off_t)100000);
  	fstat(fd, &statbuf);
  	if (statbuf.st_size != (off_t)100000) {
  		prt("no extend on truncate! not posix!\n");
  		exit(130);
  	}
  	ftruncate(fd, (off_t)0);
  }
  
  
  void
  doread(unsigned offset, unsigned size)
  {
  	off_t ret;
  	unsigned iret;
  
  	offset -= offset % readbdy;
  	if (size == 0) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping zero size read\n");
  		log4(OP_SKIPPED, OP_READ, offset, size);
  		return;
  	}
  	if (size + offset > file_size) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping seek/read past end of file\n");
  		log4(OP_SKIPPED, OP_READ, offset, size);
  		return;
  	}
  
  	log4(OP_READ, offset, size, 0);
  
  	if (testcalls <= simulatedopcount)
  		return;
  
  	if (!quiet && ((progressinterval &&
  			testcalls % progressinterval == 0) ||
  		       (debug &&
  			(monitorstart == -1 ||
  			 (offset + size > monitorstart &&
  			  (monitorend == -1 || offset <= monitorend))))))
  		prt("%lu read\t0x%x thru\t0x%x\t(0x%x bytes)\n", testcalls,
  		    offset, offset + size - 1, size);
  	ret = lseek(fd, (off_t)offset, SEEK_SET);
  	if (ret == (off_t)-1) {
  		prterr("doread: lseek");
  		report_failure(140);
  	}
  	iret = read(fd, temp_buf, size);
  	if (iret != size) {
  		if (iret == -1)
  			prterr("doread: read");
  		else
  			prt("short read: 0x%x bytes instead of 0x%x\n",
  			    iret, size);
  		report_failure(141);
  	}
  	check_buffers(offset, size);
  }
  
  
  void
  check_eofpage(char *s, unsigned offset, char *p, int size)
  {
  	unsigned last_page, should_be_zero;
  
  	if (offset + size <= (file_size & ~page_mask))
  		return;
  	/*
  	 * we landed in the last page of the file
  	 * test to make sure the VM system provided 0's 
  	 * beyond the true end of the file mapping
  	 * (as required by mmap def in 1996 posix 1003.1)
  	 */
  	last_page = ((int)p + (offset & page_mask) + size) & ~page_mask;
  
  	for (should_be_zero = last_page + (file_size & page_mask);
  	     should_be_zero < last_page + page_size;
  	     should_be_zero++)
  		if (*(char *)should_be_zero) {
  			prt("Mapped %s: non-zero data past EOF (0x%llx) page offset 0x%x is 0x%04x\n",
  			    s, file_size - 1, should_be_zero & page_mask,
  			    short_at(should_be_zero));
  			report_failure(205);
  		}
  }
  
  
  void
  domapread(unsigned offset, unsigned size)
  {
  	unsigned pg_offset;
  	unsigned map_size;
  	char    *p;
  
  	offset -= offset % readbdy;
  	if (size == 0) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping zero size read\n");
  		log4(OP_SKIPPED, OP_MAPREAD, offset, size);
  		return;
  	}
  	if (size + offset > file_size) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping seek/read past end of file\n");
  		log4(OP_SKIPPED, OP_MAPREAD, offset, size);
  		return;
  	}
  
  	log4(OP_MAPREAD, offset, size, 0);
  
  	if (testcalls <= simulatedopcount)
  		return;
  
  	if (!quiet && ((progressinterval &&
  			testcalls % progressinterval == 0) ||
  		       (debug &&
  			(monitorstart == -1 ||
  			 (offset + size > monitorstart &&
  			  (monitorend == -1 || offset <= monitorend))))))
  		prt("%lu mapread\t0x%x thru\t0x%x\t(0x%x bytes)\n", testcalls,
  		    offset, offset + size - 1, size);
  
  	pg_offset = offset & page_mask;
  	map_size  = pg_offset + size;
  
  	if ((p = (char *)mmap(0, map_size, PROT_READ, MAP_FILE | MAP_SHARED, fd,
  			      (off_t)(offset - pg_offset))) == (char *)-1) {
  		prterr("domapread: mmap");
  		report_failure(190);
  	}
  	memcpy(temp_buf, p + pg_offset, size);
  
  	check_eofpage("Read", offset, p, size);
  
  	if (munmap(p, map_size) != 0) {
  		prterr("domapread: munmap");
  		report_failure(191);
  	}
  
  	check_buffers(offset, size);
  }
  
  
  void
  gendata(char *original_buf, char *good_buf, unsigned offset, unsigned size)
  {
  	while (size--) {
  		good_buf[offset] = testcalls % 256; 
  		if (offset % 2)
  			good_buf[offset] += original_buf[offset];
  		offset++;
  	}
  }
  
  
  void
  dowrite(unsigned offset, unsigned size)
  {
  	off_t ret;
  	unsigned iret;
  
  	offset -= offset % writebdy;
  	if (size == 0) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping zero size write\n");
  		log4(OP_SKIPPED, OP_WRITE, offset, size);
  		return;
  	}
  
  	log4(OP_WRITE, offset, size, file_size);
  
  	gendata(original_buf, good_buf, offset, size);
  	if (file_size < offset + size) {
  		if (file_size < offset)
  			memset(good_buf + file_size, '\0', offset - file_size);
  		file_size = offset + size;
  		if (lite) {
  			warn("Lite file size bug in fsx!");
  			report_failure(149);
  		}
  	}
  
  	if (testcalls <= simulatedopcount)
  		return;
  
  	if (!quiet && ((progressinterval &&
  			testcalls % progressinterval == 0) ||
  		       (debug &&
  			(monitorstart == -1 ||
  			 (offset + size > monitorstart &&
  			  (monitorend == -1 || offset <= monitorend))))))
  		prt("%lu write\t0x%x thru\t0x%x\t(0x%x bytes)\n", testcalls,
  		    offset, offset + size - 1, size);
  	ret = lseek(fd, (off_t)offset, SEEK_SET);
  	if (ret == (off_t)-1) {
  		prterr("dowrite: lseek");
  		report_failure(150);
  	}
  	iret = write(fd, good_buf + offset, size);
  	if (iret != size) {
  		if (iret == -1)
  			prterr("dowrite: write");
  		else
  			prt("short write: 0x%x bytes instead of 0x%x\n",
  			    iret, size);
  		report_failure(151);
  	}
  }
  
  
  void
  domapwrite(unsigned offset, unsigned size)
  {
  	unsigned pg_offset;
  	unsigned map_size;
  	off_t    cur_filesize;
  	char    *p;
  
  	offset -= offset % writebdy;
  	if (size == 0) {
  		if (!quiet && testcalls > simulatedopcount)
  			prt("skipping zero size write\n");
  		log4(OP_SKIPPED, OP_MAPWRITE, offset, size);
  		return;
  	}
  	cur_filesize = file_size;
  
  	log4(OP_MAPWRITE, offset, size, 0);
  
  	gendata(original_buf, good_buf, offset, size);
  	if (file_size < offset + size) {
  		if (file_size < offset)
  			memset(good_buf + file_size, '\0', offset - file_size);
  		file_size = offset + size;
  		if (lite) {
  			warn("Lite file size bug in fsx!");
  			report_failure(200);
  		}
  	}
  
  	if (testcalls <= simulatedopcount)
  		return;
  
  	if (!quiet && ((progressinterval &&
  			testcalls % progressinterval == 0) ||
  		       (debug &&
  			(monitorstart == -1 ||
  			 (offset + size > monitorstart &&
  			  (monitorend == -1 || offset <= monitorend))))))
  		prt("%lu mapwrite\t0x%x thru\t0x%x\t(0x%x bytes)\n", testcalls,
  		    offset, offset + size - 1, size);
  
  	if (file_size > cur_filesize) {
  		if (ftruncate(fd, file_size) == -1) {
  			prterr("domapwrite: ftruncate");
  			exit(201);
  		}
  	}
  	pg_offset = offset & page_mask;
  	map_size  = pg_offset + size;
  
  	if ((p = (char *)mmap(0, map_size, PROT_READ | PROT_WRITE,
  			      MAP_FILE | MAP_SHARED, fd,
  			      (off_t)(offset - pg_offset))) == (char *)-1) {
  		prterr("domapwrite: mmap");
  		report_failure(202);
  	}
  	memcpy(p + pg_offset, good_buf + offset, size);
  	if (msync(p, map_size, 0) != 0) {
  		prterr("domapwrite: msync");
  		report_failure(203);
  	}
  
  	check_eofpage("Write", offset, p, size);
  
  	if (munmap(p, map_size) != 0) {
  		prterr("domapwrite: munmap");
  		report_failure(204);
  	}
  }
  
  
  void
  dotruncate(unsigned size)
  {
  	int oldsize = file_size;
  
  	size -= size % truncbdy;
  	if (size > biggest) {
  		biggest = size;
  		if (!quiet && testcalls > simulatedopcount)
  			prt("truncating to largest ever: 0x%x\n", size);
  	}
  
  	log4(OP_TRUNCATE, size, (unsigned)file_size, 0);
  
  	if (size > file_size)
  		memset(good_buf + file_size, '\0', size - file_size);
  	file_size = size;
  
  	if (testcalls <= simulatedopcount)
  		return;
  	
  	if ((progressinterval && testcalls % progressinterval == 0) ||
  	    (debug && (monitorstart == -1 || monitorend == -1 ||
  		       size <= monitorend)))
  		prt("%lu trunc\tfrom 0x%x to 0x%x\n", testcalls, oldsize, size);
  	if (ftruncate(fd, (off_t)size) == -1) {
  		prt("ftruncate1: %x\n", size);
  		prterr("dotruncate: ftruncate");
  		report_failure(160);
  	}
  }
  
  
  void
  writefileimage()
  {
  	ssize_t iret;
  
  	if (lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) {
  		prterr("writefileimage: lseek");
  		report_failure(171);
  	}
  	iret = write(fd, good_buf, file_size);
  	if ((off_t)iret != file_size) {
  		if (iret == -1)
  			prterr("writefileimage: write");
  		else
  			prt("short write: 0x%x bytes instead of 0x%llx\n",
  			    iret, (unsigned long long)file_size);
  		report_failure(172);
  	}
  	if (lite ? 0 : ftruncate(fd, file_size) == -1) {
  		prt("ftruncate2: %llx\n", (unsigned long long)file_size);
  		prterr("writefileimage: ftruncate");
  		report_failure(173);
  	}
  }
  
  
  void
  docloseopen(void)
  { 
  	if (testcalls <= simulatedopcount)
  		return;
  
  	if (debug)
  		prt("%lu close/open\n", testcalls);
  	if (close(fd)) {
  		prterr("docloseopen: close");
  		report_failure(180);
  	}
  	fd = open(fname, O_RDWR, 0);
  	if (fd < 0) {
  		prterr("docloseopen: open");
  		report_failure(181);
  	}
  }
  
  
  void
  test(void)
  {
  	unsigned long	offset;
  	unsigned long	size = maxoplen;
  	unsigned long	rv = random();
  	unsigned long	op = rv % (3 + !lite + mapped_writes);
  
  	/* turn off the map read if necessary */
  
  	if (op == 2 && !mapped_reads)
  	    op = 0;
  
  	if (simulatedopcount > 0 && testcalls == simulatedopcount)
  		writefileimage();
  
  	testcalls++;
  
  	if (closeprob)
  		closeopen = (rv >> 3) < (1 << 28) / closeprob;
  
  	if (debugstart > 0 && testcalls >= debugstart)
  		debug = 1;
  
  	if (!quiet && testcalls < simulatedopcount && testcalls % 100000 == 0)
  		prt("%lu...\n", testcalls);
  
  	/*
  	 * READ:	op = 0
  	 * WRITE:	op = 1
  	 * MAPREAD:     op = 2
  	 * TRUNCATE:	op = 3
  	 * MAPWRITE:    op = 3 or 4
  	 */
  	if (lite ? 0 : op == 3 && style == 0) /* vanilla truncate? */
  		dotruncate(random() % maxfilelen);
  	else {
  		if (randomoplen)
  			size = random() % (maxoplen+1);
  		if (lite ? 0 : op == 3)
  			dotruncate(size);
  		else {
  			offset = random();
  			if (op == 1 || op == (lite ? 3 : 4)) {
  				offset %= maxfilelen;
  				if (offset + size > maxfilelen)
  					size = maxfilelen - offset;
  				if (op != 1)
  					domapwrite(offset, size);
  				else
  					dowrite(offset, size);
  			} else {
  				if (file_size)
  					offset %= file_size;
  				else
  					offset = 0;
  				if (offset + size > file_size)
  					size = file_size - offset;
  				if (op != 0)
  					domapread(offset, size);
  				else
  					doread(offset, size);
  			}
  		}
  	}
  	if (sizechecks && testcalls > simulatedopcount)
  		check_size();
  	if (closeopen)
  		docloseopen();
  }
  
  
  void
  cleanup(sig)
  	int	sig;
  {
  	if (sig)
  		prt("signal %d\n", sig);
  	prt("testcalls = %lu\n", testcalls);
  	exit(sig);
  }
  
  
  void
  usage(void)
  {
  	fprintf(stdout, "usage: %s",
  		"fsx [-dnqLOW] [-b opnum] [-c Prob] [-l flen] [-m start:end] [-o oplen] [-p progressinterval] [-r readbdy] [-s style] [-t truncbdy] [-w writebdy] [-D startingop] [-N numops] [-P dirpath] [-S seed] fname\n\
  	-b opnum: beginning operation number (default 1)\n\
  	-c P: 1 in P chance of file close+open at each op (default infinity)\n\
  	-d: debug output for all operations\n\
  	-l flen: the upper bound on file size (default 262144)\n\
  	-m startop:endop: monitor (print debug output) specified byte range (default 0:infinity)\n\
  	-n: no verifications of file size\n\
  	-o oplen: the upper bound on operation size (default 65536)\n\
  	-p progressinterval: debug output at specified operation interval\n\
  	-q: quieter operation\n\
  	-r readbdy: 4096 would make reads page aligned (default 1)\n\
  	-s style: 1 gives smaller truncates (default 0)\n\
  	-t truncbdy: 4096 would make truncates page aligned (default 1)\n\
  	-w writebdy: 4096 would make writes page aligned (default 1)\n\
  	-D startingop: debug output starting at specified operation\n\
  	-L: fsxLite - no file creations & no file size changes\n\
  	-N numops: total # operations to do (default infinity)\n\
  	-O: use oplen (see -o flag) for every op (default random)\n\
  	-P dirpath: save .fsxlog and .fsxgood files in dirpath (default ./)\n\
  	-S seed: for random # generator (default 1) 0 gets timestamp\n\
  	-W: mapped write operations DISabled\n\
  	-R: mapped read operations DISabled)\n\
  	fname: this filename is REQUIRED (no default)\n");
  	exit(90);
  }
  
  
  int
  getnum(char *s, char **e)
  {
  	int ret = -1;
  
  	*e = NULL;
  	ret = strtol(s, e, 0);
  	if (*e)
  		switch (**e) {
  		case 'b':
  		case 'B':
  			ret *= 512;
  			*e = *e + 1;
  			break;
  		case 'k':
  		case 'K':
  			ret *= 1024;
  			*e = *e + 1;
  			break;
  		case 'm':
  		case 'M':
  			ret *= 1024*1024;
  			*e = *e + 1;
  			break;
  		case 'w':
  		case 'W':
  			ret *= 4;
  			*e = *e + 1;
  			break;
  		}
  	return (ret);
  }
  
  
  int
  main(int argc, char **argv)
  {
  	int	i, ch;
  	char	*endp;
  	char goodfile[1024];
  	char logfile[1024];
  
  	goodfile[0] = 0;
  	logfile[0] = 0;
  
  	page_size = getpagesize();
  	page_mask = page_size - 1;
  
  	setvbuf(stdout, NULL, _IOLBF, 0); /* line buffered stdout */
  
  	while ((ch = getopt(argc, argv, "b:c:dl:m:no:p:qr:s:t:w:D:LN:OP:RS:W"))
  	       != EOF)
  		switch (ch) {
  		case 'b':
  			simulatedopcount = getnum(optarg, &endp);
  			if (!quiet)
  				fprintf(stdout, "Will begin at operation %ld\n",
  					simulatedopcount);
  			if (simulatedopcount == 0)
  				usage();
  			simulatedopcount -= 1;
  			break;
  		case 'c':
  			closeprob = getnum(optarg, &endp);
  			if (!quiet)
  				fprintf(stdout,
  					"Chance of close/open is 1 in %d\n",
  					closeprob);
  			if (closeprob <= 0)
  				usage();
  			break;
  		case 'd':
  			debug = 1;
  			break;
  		case 'l':
  			maxfilelen = getnum(optarg, &endp);
  			if (maxfilelen <= 0)
  				usage();
  			break;
  		case 'm':
  			monitorstart = getnum(optarg, &endp);
  			if (monitorstart < 0)
  				usage();
  			if (!endp || *endp++ != ':')
  				usage();
  			monitorend = getnum(endp, &endp);
  			if (monitorend < 0)
  				usage();
  			if (monitorend == 0)
  				monitorend = -1; /* aka infinity */
  			debug = 1;
  		case 'n':
  			sizechecks = 0;
  			break;
  		case 'o':
  			maxoplen = getnum(optarg, &endp);
  			if (maxoplen <= 0)
  				usage();
  			break;
  		case 'p':
  			progressinterval = getnum(optarg, &endp);
  			if (progressinterval < 0)
  				usage();
  			break;
  		case 'q':
  			quiet = 1;
  			break;
  		case 'r':
  			readbdy = getnum(optarg, &endp);
  			if (readbdy <= 0)
  				usage();
  			break;
  		case 's':
  			style = getnum(optarg, &endp);
  			if (style < 0 || style > 1)
  				usage();
  			break;
  		case 't':
  			truncbdy = getnum(optarg, &endp);
  			if (truncbdy <= 0)
  				usage();
  			break;
  		case 'w':
  			writebdy = getnum(optarg, &endp);
  			if (writebdy <= 0)
  				usage();
  			break;
  		case 'D':
  			debugstart = getnum(optarg, &endp);
  			if (debugstart < 1)
  				usage();
  			break;
  		case 'L':
  			lite = 1;
  			break;
  		case 'N':
  			numops = getnum(optarg, &endp);
  			if (numops < 0)
  				usage();
  			break;
  		case 'O':
  			randomoplen = 0;
  			break;
  		case 'P':
  			strncpy(goodfile, optarg, sizeof(goodfile));
  			strcat(goodfile, "/");
  			strncpy(logfile, optarg, sizeof(logfile));
  			strcat(logfile, "/");
  			break;
  		case 'R':
  			mapped_reads = 0;
  			break;
  		case 'S':
  			seed = getnum(optarg, &endp);
  			if (seed == 0)
  				seed = time(0) % 10000;
  			if (!quiet)
  				fprintf(stdout, "Seed set to %d\n", seed);
  			if (seed < 0)
  				usage();
  			break;
  		case 'W':
  			mapped_writes = 0;
  			if (!quiet)
  				fprintf(stdout, "mapped writes DISABLED\n");
  			break;
  
  		default:
  			usage();
  			/* NOTREACHED */
  		}
  	argc -= optind;
  	argv += optind;
  	if (argc != 1)
  		usage();
  	fname = argv[0];
  
  	signal(SIGHUP,	cleanup);
  	signal(SIGINT,	cleanup);
  	signal(SIGPIPE,	cleanup);
  	signal(SIGALRM,	cleanup);
  	signal(SIGTERM,	cleanup);
  	signal(SIGXCPU,	cleanup);
  	signal(SIGXFSZ,	cleanup);
  	signal(SIGVTALRM,	cleanup);
  	signal(SIGUSR1,	cleanup);
  	signal(SIGUSR2,	cleanup);
  
  	initstate(seed, state, 256);
  	setstate(state);
  	fd = open(fname, O_RDWR|(lite ? 0 : O_CREAT|O_TRUNC), 0666);
  	if (fd < 0) {
  		prterr(fname);
  		exit(91);
  	}
  	strncat(goodfile, fname, 256);
  	strcat (goodfile, ".fsxgood");
  	fsxgoodfd = open(goodfile, O_RDWR|O_CREAT|O_TRUNC, 0666);
  	if (fsxgoodfd < 0) {
  		prterr(goodfile);
  		exit(92);
  	}
  	strncat(logfile, fname, 256);
  	strcat (logfile, ".fsxlog");
  	fsxlogf = fopen(logfile, "w");
  	if (fsxlogf == NULL) {
  		prterr(logfile);
  		exit(93);
  	}
  	if (lite) {
  		off_t ret;
  		file_size = maxfilelen = lseek(fd, (off_t)0, SEEK_END);
  		if (file_size == (off_t)-1) {
  			prterr(fname);
  			warn("main: lseek eof");
  			exit(94);
  		}
  		ret = lseek(fd, (off_t)0, SEEK_SET);
  		if (ret == (off_t)-1) {
  			prterr(fname);
  			warn("main: lseek 0");
  			exit(95);
  		}
  	}
  	original_buf = (char *) malloc(maxfilelen);
  	for (i = 0; i < maxfilelen; i++)
  		original_buf[i] = random() % 256;
  	good_buf = (char *) malloc(maxfilelen);
  	memset(good_buf, '\0', maxfilelen);
  	temp_buf = (char *) malloc(maxoplen);
  	memset(temp_buf, '\0', maxoplen);
  	if (lite) {	/* zero entire existing file */
  		ssize_t written;
  
  		written = write(fd, good_buf, (size_t)maxfilelen);
  		if (written != maxfilelen) {
  			if (written == -1) {
  				prterr(fname);
  				warn("main: error on write");
  			} else
  				warn("main: short write, 0x%x bytes instead of 0x%x\n",
  				     (unsigned)written, maxfilelen);
  			exit(98);
  		}
  	} else 
  		check_trunc_hack();
  
  	while (numops == -1 || numops--)
  		test();
  
  	if (close(fd)) {
  		prterr("close");
  		report_failure(99);
  	}
  	prt("All operations completed A-OK!\n");
  
  	exit(0);
  	return 0;
  }
  
  