/*
 * Copyright (c) 2003 Sean Chittenden <seanc@FreeBSD.org>.
 * All rights reserved.
 *
 * $Id$
 */

#include <fcntl.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <err.h>
#include <time.h>

#ifdef notdef
#define DEBUG 1
#endif

#ifdef notdef
# define DO_MMAP 1
#endif

#ifdef notdef
# define DO_MMAP_ONCE 1
#endif

#ifdef notdef
# define DO_SHOW_FILENAMES 1
#endif

#ifdef DEFAULT_READSIZE
# ifndef READ_SIZE
#  define READ_SIZE MAXBSIZE
# endif
#else
# define READ_SIZE 0
#endif

struct bs {
  off_t size;
  int fd;
  struct stat fs;
  struct timeval t_start;
  struct timeval t_final;
  void *addr;
  char *filename;
};

struct timeval t_teststart, t_testfinal;
int npages, psize, ret, wret;


inline void setup_fd(struct bs *s) {
  s->fd = open(s->filename, O_RDWR);
  if (s->fd < 0)
    err(1, "Unable to open: %s", s->filename);

#ifdef DEBUG
  fprintf(stderr, "open():\t\t%s\n", s->filename);
#endif

  ret = fstat(s->fd, &s->fs);
  if (ret < 0)
    err(1, "Unable to fstat: %s", s->filename);

#ifdef DEBUG
  fprintf(stderr, "fstat():\t%d (st_size: %d)\n", s->fd, (int)s->fs.st_size);
#endif

  if (READ_SIZE != 0)
    s->size = READ_SIZE;
  else
    s->size = s->fs.st_size;

  npages = s->size / psize;
  if ((s->size % psize) != 0)
    npages++;
#ifdef DEBUG
  fprintf(stderr, "pages:\t\t%d\n", npages);
#endif
  s->size = npages * psize;
#ifdef DEBUG
  fprintf(stderr, "size:\t\t%d\n", (int)s->size);
#endif


#ifdef DO_MMAP
  s->addr = mmap(0, s->size, PROT_READ|PROT_WRITE, MAP_NOSYNC|MAP_SHARED, s->fd, 0);
  if (s->addr == MAP_FAILED)
    err(1, "Unable to mmap() file %s\n", s->filename);

#ifdef DEBUG
  fprintf(stderr, "mmap():\t\t%d\n", s->fd);
#endif


  ret = madvise(s->addr, s->size, MADV_SEQUENTIAL);
  if (ret < 0)
    err(1, "Unable to madvise() region %p\n", s->addr);

#ifdef DEBUG
  fprintf(stderr, "madvise():\t%p\n", s->addr);
#endif
#endif
  return;
}


inline void close_fd(struct bs *s) {
#ifdef DO_MMAP
  ret = munmap(s->addr, s->size);
  if (ret < 0)
    err(1, "Unable to munmap() file %p\n", s->addr);

#ifdef DEBUG
  fprintf(stderr, "munmap():\t%p\n", s->addr);
#endif
#endif

  ret = close(s->fd);
  if (ret < 0)
    err(1, "Unable to close: %s\n", s->filename);

#ifdef DEBUG
  fprintf(stderr, "close():\t%d\n", s->fd);
#endif
}


inline int bench(struct bs *s) {
  ret = gettimeofday(&s->t_start, NULL);
  if (ret < 0)
    err(1, "Unable to get the time of day");

#ifndef DO_MMAP_ONCE
  setup_fd(s);
#endif

  /* Do some tests */
#ifdef DO_MMAP
  write(STDOUT_FILENO, s->addr, s->size);
#else
  s->addr = malloc(s->size);
  if (s->addr == NULL)
    err(1, "Unable to malloc %d bytes", s->size);

  do {
    ret = read(s->fd, s->addr, s->size);
    if (ret < 0)
      err(1, "Unable to read from fd %d", s->fd);
    wret = write(STDOUT_FILENO, s->addr, ret);
  } while (ret > 0);

  free(s->addr);
#endif
  /* End tests */

#ifndef DO_MMAP_ONCE
  close_fd(s);
#endif

  ret = gettimeofday(&s->t_final, NULL);
  if (ret < 0)
    err(1, "Unable to get the time of day");

  return(0);
}



int main(int argc, char *argv[]) {
  int i, j, numfiles, numiterations;
  struct bs *s;

  numiterations = 100000;

  if (argc == 0) {
    fprintf(stderr, "Please specify one or more files as arguments\n");
    exit(1);
  }

  numfiles = argc - 1;

  s = (struct bs *)malloc(sizeof(struct bs) * numfiles);
  if (s == NULL)
    err(1, "Unable to malloc enough data for benchmark struct array");

  for (i = 0; i < numfiles; i++) {
    s[i].addr = NULL;
    s[i].size = -1;
    s[i].fd = -1;
    s[i].addr = NULL;
    s[i].filename = argv[i + 1];
  }

#ifdef DO_SHOW_FILENAMES
  fprintf(stderr, "Beginning tests with file(s):\t\t");
  for (i = 0; i < numfiles; i++)
    fprintf(stderr, "%s, ", s[i].filename);
  fprintf(stderr, "\n");
#endif

  psize = getpagesize();
  fprintf(stderr, "Page size:\t\t\t\t%d\n", psize);

#ifndef DO_MMAP
#ifdef DEFAULT_READSIZE
  if (READ_SIZE != 0)
    fprintf(stderr, "File read size is default read size:\t%d\n", READ_SIZE);
  else
    fprintf(stderr, "File read size is the same as the file size\n");
#else
  fprintf(stderr, "File read size is the same as the file size\n");
#endif
#else
  fprintf(stderr, "File read size is the same as the file size\n");
#endif

  fprintf(stderr, "Number of iterations:\t\t\t%d\n", numiterations);

  ret = gettimeofday(&t_teststart, NULL);
  if (ret < 0)
    err(1, "Unable to get the time of day");


#ifdef DO_MMAP_ONCE
  for (i = 0; i < numfiles; i++)
    setup_fd(&s[i]);
#endif

  /* some kind of benchmarking */
  for (i = 0, j = 0; j < numiterations; i++, j++) {
    if (i == numfiles)
      i = 0;

    bench(&s[i]);
#ifdef DEBUG
    fprintf(stderr, "Time:\t\t%lu.%lu\n",
	    (s[i]->t_final.tv_sec -  s[i]->t_start.tv_sec),
	    (s[i]->t_final.tv_usec - s[i]->t_start.tv_usec));
#endif
  }


#ifdef DO_MMAP_ONCE
  for (i = 0; i < numfiles; i++)
    close_fd(&s[i]);
#endif

  ret = gettimeofday(&t_testfinal, NULL);
  if (ret < 0)
    err(1, "Unable to get the time of day");

  fprintf(stderr, "Start time:\t\t\t\t%lu.%lu\n", t_teststart.tv_sec, t_teststart.tv_usec);
  fprintf(stderr, "Time:\t\t\t\t\t%lu.%lu\n",
	  (t_testfinal.tv_sec - t_teststart.tv_sec),
	  (t_testfinal.tv_usec - t_teststart.tv_usec));

  fprintf(stderr, "\nCompleted tests\n");
  return(0);
}