/*
   Copyright (c) 2005, 2012, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
*/

/*
  InnoDB offline file checksum utility.  85% of the code in this utility
  is included from the InnoDB codebase.

  The final 15% was originally written by Mark Smith of Danga
  Interactive, Inc. <junior@danga.com>

  Published with a permission.
*/

#include <my_global.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifndef __WIN__
# include <unistd.h>
#endif
#include <my_getopt.h>
#include <m_string.h>
#include <welcome_copyright_notice.h> /* ORACLE_WELCOME_COPYRIGHT_NOTICE */
#include <string.h>

/* Only parts of these files are included from the InnoDB codebase.
The parts not included are excluded by #ifndef UNIV_INNOCHECKSUM. */

#include "univ.i"                /*  include all of this */

#define FLST_NODE_SIZE (2 * FIL_ADDR_SIZE)
#define FSEG_PAGE_DATA FIL_PAGE_DATA

#include "ut0ut.h"
#include "ut0byte.h"
#include "mach0data.h"
#include "fsp0types.h"
#include "rem0rec.h"
#include "buf0checksum.h"        /* buf_calc_page_*() */
#include "fil0fil.h"             /* FIL_* */
#include "page0page.h"           /* PAGE_* */
#include "page0zip.h"            /* page_zip_*() */
#include "trx0undo.h"            /* TRX_* */
#include "fsp0fsp.h"             /* fsp_flags_get_page_size() &
                                    fsp_flags_get_zip_size() */
#include "mach0data.h"           /* mach_read_from_4() */
#include "ut0crc32.h"            /* ut_crc32_init() */

#ifdef UNIV_NONINL
# include "fsp0fsp.ic"
# include "mach0data.ic"
# include "ut0rnd.ic"
#endif

/* Global variables */
static my_bool verbose;
static my_bool debug;
static my_bool skip_corrupt;
static my_bool just_count;
static ulong start_page;
static ulong end_page;
static ulong do_page;
static my_bool use_end_page;
static my_bool do_one_page;
ulong srv_page_size;              /* replaces declaration in srv0srv.c */
static ulong physical_page_size;  /* Page size in bytes on disk. */
static ulong logical_page_size;   /* Page size when uncompressed. */
static bool compressed= false;    /* Is tablespace compressed */

/* Get the page size of the filespace from the filespace header. */
static
my_bool
get_page_size(
/*==========*/
  FILE*  f,                     /*!< in: file pointer, must be open
                                         and set to start of file */
  byte* buf,                    /*!< in: buffer used to read the page */
  ulong* logical_page_size,     /*!< out: Logical/Uncompressed page size */
  ulong* physical_page_size)    /*!< out: Physical/Commpressed page size */
{
  ulong flags;

  int bytes= fread(buf, 1, UNIV_PAGE_SIZE_MIN, f);

  if (ferror(f))
  {
    perror("Error reading file header");
    return FALSE;
  }

  if (bytes != UNIV_PAGE_SIZE_MIN)
  {
    fprintf(stderr, "Error; Was not able to read the minimum page size ");
    fprintf(stderr, "of %d bytes.  Bytes read was %d\n", UNIV_PAGE_SIZE_MIN, bytes);
    return FALSE;
  }

  rewind(f);

  flags = mach_read_from_4(buf + FIL_PAGE_DATA + FSP_SPACE_FLAGS);

  /* srv_page_size is used by InnoDB code as UNIV_PAGE_SIZE */
  srv_page_size = *logical_page_size = fsp_flags_get_page_size(flags);

  /* fsp_flags_get_zip_size() will return zero if not compressed. */
  *physical_page_size = fsp_flags_get_zip_size(flags);
  if (*physical_page_size == 0)
  {
    *physical_page_size= *logical_page_size;
  }
  else
  {
    compressed= true;
  }
  return TRUE;
}


/* command line argument to do page checks (that's it) */
/* another argument to specify page ranges... seek to right spot and go from there */

static struct my_option innochecksum_options[] =
{
  {"help", '?', "Displays this help and exits.",
    0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"info", 'I', "Synonym for --help.",
    0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"version", 'V', "Displays version information and exits.",
    0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"verbose", 'v', "Verbose (prints progress every 5 seconds).",
    &verbose, &verbose, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"debug", 'd', "Debug mode (prints checksums for each page, implies verbose).",
    &debug, &debug, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"skip_corrupt", 'u', "Skip corrupt pages.",
    &skip_corrupt, &skip_corrupt, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"count", 'c', "Print the count of pages in the file.",
    &just_count, &just_count, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
  {"start_page", 's', "Start on this page number (0 based).",
    &start_page, &start_page, 0, GET_ULONG, REQUIRED_ARG,
    0, 0, (longlong) 2L*1024L*1024L*1024L, 0, 1, 0},
  {"end_page", 'e', "End at this page number (0 based).",
    &end_page, &end_page, 0, GET_ULONG, REQUIRED_ARG,
    0, 0, (longlong) 2L*1024L*1024L*1024L, 0, 1, 0},
  {"page", 'p', "Check only this page (0 based).",
    &do_page, &do_page, 0, GET_ULONG, REQUIRED_ARG,
    0, 0, (longlong) 2L*1024L*1024L*1024L, 0, 1, 0},
  {0, 0, 0, 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0}
};

static void print_version(void)
{
  printf("%s Ver %s, for %s (%s)\n",
         my_progname, INNODB_VERSION_STR,
         SYSTEM_TYPE, MACHINE_TYPE);
}

static void usage(void)
{
  print_version();
  puts(ORACLE_WELCOME_COPYRIGHT_NOTICE("2000"));
  printf("InnoDB offline file checksum utility.\n");
  printf("Usage: %s [-c] [-s <start page>] [-e <end page>] [-p <page>] [-v] [-d] <filename>\n", my_progname);
  my_print_help(innochecksum_options);
  my_print_variables(innochecksum_options);
}

extern "C" my_bool
innochecksum_get_one_option(
/*========================*/
  int optid,
  const struct my_option *opt __attribute__((unused)),
  char *argument __attribute__((unused)))
{
  switch (optid) {
  case 'd':
    verbose=1;	/* debug implies verbose... */
    break;
  case 'e':
    use_end_page= 1;
    break;
  case 'p':
    end_page= start_page= do_page;
    use_end_page= 1;
    do_one_page= 1;
    break;
  case 'V':
    print_version();
    exit(0);
    break;
  case 'I':
  case '?':
    usage();
    exit(0);
    break;
  }
  return 0;
}

static int get_options(
/*===================*/
  int *argc,
  char ***argv)
{
  int ho_error;

  if ((ho_error=handle_options(argc, argv, innochecksum_options, innochecksum_get_one_option)))
    exit(ho_error);

  /* The next arg must be the filename */
  if (!*argc)
  {
    usage();
    return 1;
  }
  return 0;
} /* get_options */

int main(int argc, char **argv)
{
  FILE* f;                       /* our input file */
  char* filename;                /* our input filename. */
  unsigned char *big_buf= 0, *buf;

  ulong bytes;                   /* bytes read count */
  ulint ct;                      /* current page number (0 based) */
  time_t now;                    /* current time */
  time_t lastt;                  /* last time */
  ulint oldcsum, oldcsumfield, csum, csumfield, crc32, logseq, logseqfield;
                                 /* ulints for checksum storage */
  unsigned long long int size;   /* size of file (has to be 64 bits) */
  ulint pages;                   /* number of pages in file */
  long long offset= 0;
  int fd;

  printf("InnoDB offline file checksum utility.\n");

  ut_crc32_init();

  MY_INIT(argv[0]);

  if (get_options(&argc,&argv))
    exit(1);

  if (verbose)
    my_print_variables(innochecksum_options);

  /* The file name is not optional */
  filename = *argv;
  if (*filename == '\0')
  {
    fprintf(stderr, "Error; File name missing\n");
    goto error;
  }

#ifdef _WIN32
  /* Switch off OS file buffering for the file. */

  HANDLE h = CreateFile(filename, GENERIC_READ,
   FILE_SHARE_READ|FILE_SHARE_WRITE, 0,
   OPEN_EXISTING, FILE_FLAG_NO_BUFFERING, 0);

  if (!h)
  {
    fprintf(stderr, "Error; cant open file\n");
    goto error;
  }

  if (!GetFileSizeEx(h, (LARGE_INTEGER *)&size))
  {
    fprintf(stderr, "Error; GetFileSize() failed\n");
    goto error;
  }

  fd = _open_osfhandle ((intptr_t) h, _O_RDONLY);
  if (fd < 0)
  {
    fprintf(stderr, "Error; _open_osfhandle() failed\n");
    goto error;
  }

  f = _fdopen(fd, "rb");
  if (!f)
  {
    fprintf(stderr, "Error; fdopen() failed\n");
    goto error;
  }

  /*
    Disable stdio buffering (FILE_FLAG_NO_BUFFERING requires properly IO buffers
    which stdio does not guarantee.
  */
  setvbuf(f, NULL, _IONBF, 0);

#else
  struct stat st;
  /* stat the file to get size and page count */
  if (stat(filename, &st))
  {
    fprintf(stderr, "Error; %s cannot be found\n", filename);
    goto error;
  }
  size= st.st_size;

  /* Open the file for reading */
  f= fopen(filename, "rb");
#endif

  if (f == NULL)
  {
    fprintf(stderr, "Error; %s cannot be opened", filename);
    perror(" ");
    goto error;
  }

  big_buf = (unsigned char *)malloc(2 * UNIV_PAGE_SIZE_MAX);
  if (big_buf == NULL)
  {
    fprintf(stderr, "Error; failed to allocate memory\n");
    perror("");
    goto error;
  }

  /* Make sure the page is aligned */
  buf = (unsigned char*)ut_align_down(big_buf
                                      + UNIV_PAGE_SIZE_MAX, UNIV_PAGE_SIZE_MAX);

  if (!get_page_size(f, buf, &logical_page_size, &physical_page_size))
    goto error;

  if (compressed)
  {
    printf("Table is compressed\n");
    printf("Key block size is %lu\n", physical_page_size);
  }
  else
  {
    printf("Table is uncompressed\n");
    printf("Page size is %lu\n", physical_page_size);
  }

  pages= (ulint) (size / physical_page_size);

  if (just_count)
  {
    if (verbose)
      printf("Number of pages: ");
    printf(ULINTPF "\n", pages);
    goto ok;
  }
  else if (verbose)
  {
    printf("file %s = %llu bytes (" ULINTPF " pages)...\n",
	   filename, size, pages);
    if (do_one_page)
      printf("InnoChecksum; checking page %lu\n", do_page);
    else
      printf("InnoChecksum; checking pages in range %lu to %lu\n", start_page, use_end_page ? end_page : (pages - 1));
  }

#ifdef UNIV_LINUX
  if (posix_fadvise(fileno(f), 0, 0, POSIX_FADV_SEQUENTIAL) ||
      posix_fadvise(fileno(f), 0, 0, POSIX_FADV_NOREUSE))
  {
    perror("posix_fadvise failed");
  }
#endif

  /* seek to the necessary position */
  if (start_page)
  {
    fd= fileno(f);
    if (!fd)
    {
      perror("Error; Unable to obtain file descriptor number");
      goto error;
    }

    offset= (longlong)start_page * (longlong)physical_page_size;
#ifdef _WIN32
    if (_lseeki64(fd, offset, SEEK_SET) != offset)
#else
    if (lseek(fd, offset, SEEK_SET) != offset)
#endif
    {
      perror("Error; Unable to seek to necessary offset");
      goto error;
    }
  }

  /* main checksumming loop */
  ct= start_page;
  lastt= 0;
  while (!feof(f))
  {
    bytes= fread(buf, 1, physical_page_size, f);
    if (!bytes && feof(f))
      goto ok;

    if (ferror(f))
    {
      fprintf(stderr, "Error reading %lu bytes", physical_page_size);
      perror(" ");
      goto error;
    }

    if (compressed) {
      /* compressed pages */
      if (!page_zip_verify_checksum(buf, physical_page_size)) {
        fprintf(stderr, "Fail; page " ULINTPF
		" invalid (fails compressed page checksum).\n", ct);
        if (!skip_corrupt)
          goto error;
      }
    } else {

      /* check the "stored log sequence numbers" */
      logseq= mach_read_from_4(buf + FIL_PAGE_LSN + 4);
      logseqfield= mach_read_from_4(buf + logical_page_size - FIL_PAGE_END_LSN_OLD_CHKSUM + 4);
      if (debug)
        printf("page " ULINTPF
	       ": log sequence number: first = " ULINTPF
	       "; second = " ULINTPF "\n",
	       ct, logseq, logseqfield);
      if (logseq != logseqfield)
      {
        fprintf(stderr, "Fail; page " ULINTPF
		" invalid (fails log sequence number check)\n", ct);
        if (!skip_corrupt)
          goto error;
      }

      /* check old method of checksumming */
      oldcsum= buf_calc_page_old_checksum(buf);
      oldcsumfield= mach_read_from_4(buf + logical_page_size - FIL_PAGE_END_LSN_OLD_CHKSUM);
      if (debug)
        printf("page " ULINTPF
	       ": old style: calculated = " ULINTPF
	       "; recorded = " ULINTPF "\n",
	       ct, oldcsum, oldcsumfield);
      if (oldcsumfield != mach_read_from_4(buf + FIL_PAGE_LSN) && oldcsumfield != oldcsum)
      {
        fprintf(stderr, "Fail;  page " ULINTPF
		" invalid (fails old style checksum)\n", ct);
        if (!skip_corrupt)
          goto error;
      }

      /* now check the new method */
      csum= buf_calc_page_new_checksum(buf);
      crc32= buf_calc_page_crc32(buf);
      csumfield= mach_read_from_4(buf + FIL_PAGE_SPACE_OR_CHKSUM);
      if (debug)
        printf("page " ULINTPF
	       ": new style: calculated = " ULINTPF
	       "; crc32 = " ULINTPF "; recorded = " ULINTPF "\n",
               ct, csum, crc32, csumfield);
      if (csumfield != 0 && crc32 != csumfield && csum != csumfield)
      {
        fprintf(stderr, "Fail; page " ULINTPF
		" invalid (fails innodb and crc32 checksum)\n", ct);
        if (!skip_corrupt)
          goto error;
      }
    }
    /* end if this was the last page we were supposed to check */
    if (use_end_page && (ct >= end_page))
      goto ok;

    /* do counter increase and progress printing */
    ct++;
    if (verbose)
    {
      if (ct % 64 == 0)
      {
        now= time(0);
        if (!lastt) lastt= now;
        if (now - lastt >= 1)
        {
          printf("page " ULINTPF " okay: %.3f%% done\n",
		 (ct - 1), (float) ct / pages * 100);
          lastt= now;
        }
      }
    }
  }

ok:
  free(big_buf);
  my_end(0);
  exit(0);

error:
  free(big_buf);
  my_end(0);
  exit(1);
}