Commit 943f8335 authored by unknown's avatar unknown
Browse files

a fix (bug #4214: Table corruption with myisampack and large BLOB objects). 


myisam/mi_check.c:
  a fix (bug #4214: Table corruption with myisampack and large BLOB objects).
  - pass version to the save_pack_length().
myisam/mi_packrec.c:
  a fix (bug #4214: Table corruption with myisampack and large BLOB objects).
  - code cleanup: read_pack_length() and calc_pack_length() introduced, 
                  save_pack_length() modified: now the behavior depends on packing version
  - save packing version in the share->pack.version
  - pass it to the read_pack_length()
myisam/mi_static.c:
  a fix (bug #4214: Table corruption with myisampack and large BLOB objects).
  - packing version set to 2
myisam/myisamdef.h:
  a fix (bug #4214: Table corruption with myisampack and large BLOB objects).
  - packing version slot introduced (see MI_PACK)
myisam/myisampack.c:
  a fix (bug #4214: Table corruption with myisampack and large BLOB objects).
  - code cleanup
  - pass version to the calc_pack_length() and save_pack_length()
parent 9e796abb

myisam/mi_check.c

+4 −2
Original line number Diff line number Diff line
@@ -3189,9 +3189,11 @@ int sort_write_record(MI_SORT_PARAM *sort_param) 
      break;

    case COMPRESSED_RECORD:

      reclength=info->packed_length;

      length=save_pack_length(block_buff,reclength);

      length= save_pack_length((uint) share->pack.version, block_buff,

                               reclength);

      if (info->s->base.blobs)

	length+=save_pack_length(block_buff+length,info->blob_length);

	length+= save_pack_length((uint) share->pack.version,

	                          block_buff + length, info->blob_length);

      if (my_b_write(&info->rec_cache,block_buff,length) ||

	  my_b_write(&info->rec_cache,(byte*) sort_param->rec_buff,reclength))

      {

myisam/mi_packrec.c

+53 −60
Original line number Diff line number Diff line
@@ -149,11 +149,12 @@ my_bool _mi_read_pack_info(MI_INFO *info, pbool fix_keys) 
      my_errno=HA_ERR_END_OF_FILE;

    goto err0;

  }

  if (memcmp((byte*) header,(byte*) myisam_pack_file_magic,4))

  if (memcmp((byte*) header, (byte*) myisam_pack_file_magic, 3))

  {

    my_errno=HA_ERR_WRONG_IN_RECORD;

    goto err0;

  }

  share->pack.version= header[3];

  share->pack.header_length=	uint4korr(header+4);

  share->min_pack_length=(uint) uint4korr(header+8);

  share->max_pack_length=(uint) uint4korr(header+12);
@@ -1040,38 +1041,12 @@ uint _mi_pack_get_block_info(MI_INFO *myisam, MI_BLOCK_INFO *info, File file, 
      return BLOCK_FATAL_ERROR;

    DBUG_DUMP("header",(byte*) header,ref_length);

  }

  if (header[0] < 254)

  {

    info->rec_len=header[0];

    head_length=1;

  }

  else if (header[0] == 254)

  {

    info->rec_len=uint2korr(header+1);

    head_length=3;

  }

  else

  {

    info->rec_len=uint3korr(header+1);

    head_length=4;

  }

  head_length= read_pack_length((uint) myisam->s->pack.version, header,

                                &info->rec_len);

  if (myisam->s->base.blobs)

  {

    if (header[head_length] < 254)

    {

      info->blob_len=header[head_length];

      head_length++;

    }

    else if (header[head_length] == 254)

    {

      info->blob_len=uint2korr(header+head_length+1);

      head_length+=3;

    }

    else

    {

      info->blob_len=uint3korr(header+head_length+1);

      head_length+=4;

    }

    head_length+= read_pack_length((uint) myisam->s->pack.version,

                                   header + head_length, &info->blob_len);

    if (!(mi_alloc_rec_buff(myisam,info->rec_len + info->blob_len,

			    &myisam->rec_buff)))

      return BLOCK_FATAL_ERROR;			/* not enough memory */
@@ -1220,34 +1195,12 @@ void _mi_unmap_file(MI_INFO *info) 
static uchar *_mi_mempack_get_block_info(MI_INFO *myisam,MI_BLOCK_INFO *info,

					 uchar *header)

{

  if (header[0] < 254)

    info->rec_len= *header++;

  else if (header[0] == 254)

  {

    info->rec_len=uint2korr(header+1);

    header+=3;

  }

  else

  {

    info->rec_len=uint3korr(header+1);

    header+=4;

  }

  header+= read_pack_length((uint) myisam->s->pack.version, header,

                            &info->rec_len);

  if (myisam->s->base.blobs)

  {

    if (header[0] < 254)

    {

      info->blob_len= *header++;

    }

    else if (header[0] == 254)

    {

      info->blob_len=uint2korr(header+1);

      header+=3;

    }

    else

    {

      info->blob_len=uint3korr(header+1);

      header+=4;

    }

    header+= read_pack_length((uint) myisam->s->pack.version, header,

                              &info->blob_len);

    /* mi_alloc_rec_buff sets my_errno on error */

    if (!(mi_alloc_rec_buff(myisam, info->blob_len,

			    &myisam->rec_buff)))
@@ -1319,7 +1272,7 @@ static int _mi_read_rnd_mempack_record(MI_INFO *info, byte *buf, 


	/* Save length of row */



uint save_pack_length(byte *block_buff,ulong length)

uint save_pack_length(uint version, byte *block_buff, ulong length)

{

  if (length < 254)

  {
@@ -1333,6 +1286,46 @@ uint save_pack_length(byte *block_buff,ulong length) 
    return 3;

  }

  *(uchar*) block_buff=255;

  if (version == 1) /* old format */

  {

    DBUG_ASSERT(length <= 0xFFFFFF);

    int3store(block_buff + 1, (ulong) length);

    return 4;

  }

  else

  {

    int4store(block_buff + 1, (ulong) length);

    return 5;

  }

}





uint read_pack_length(uint version, const uchar *buf, ulong *length)

{

  if (buf[0] < 254)

  {

    *length= buf[0];

    return 1;

  }

  else if (buf[0] == 254)

  {

    *length= uint2korr(buf + 1);

    return 3;

  }

  if (version == 1) /* old format */

  {

    *length= uint3korr(buf + 1);

    return 4;

  }

  else

  {

    *length= uint4korr(buf + 1);

    return 5;

  }

}





uint calc_pack_length(uint version, ulong length)

{

  return (length < 254) ? 1 : (length < 65536) ? 3 : (version == 1) ? 4 : 5;

}

myisam/mi_static.c

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ LIST *myisam_open_list=0; 
uchar	NEAR myisam_file_magic[]=

{ (uchar) 254, (uchar) 254,'\007', '\001', };

uchar	NEAR myisam_pack_file_magic[]=

{ (uchar) 254, (uchar) 254,'\010', '\001', };

{ (uchar) 254, (uchar) 254,'\010', '\002', };

my_string myisam_log_filename=(char*) "myisam.log";

File	myisam_log_file= -1;

uint	myisam_quick_table_bits=9;

myisam/myisamdef.h

+4 −1
Original line number Diff line number Diff line
@@ -149,6 +149,7 @@ typedef struct st_mi_blob /* Info of record */ 
typedef struct st_mi_isam_pack {

  ulong header_length;

  uint ref_length;

  uchar version;

} MI_PACK;
@@ -669,7 +670,9 @@ extern void _myisam_log_record(enum myisam_log_commands command,MI_INFO *info, 
			      int result);

extern my_bool _mi_memmap_file(MI_INFO *info);

extern void _mi_unmap_file(MI_INFO *info);

extern uint save_pack_length(byte *block_buff,ulong length);

extern uint save_pack_length(uint version, byte *block_buff, ulong length);

extern uint read_pack_length(uint version, const uchar *buf, ulong *length);

extern uint calc_pack_length(uint version, ulong length);



uint mi_state_info_write(File file, MI_STATE_INFO *state, uint pWrite);

char *mi_state_info_read(char *ptr, MI_STATE_INFO *state);

myisam/myisampack.c

+7 −18
Original line number Diff line number Diff line
@@ -1666,6 +1666,7 @@ static int compress_isam_file(PACK_MRG_INFO *mrg, HUFF_COUNTS *huff_counts) 
  HUFF_COUNTS *count,*end_count;

  HUFF_TREE *tree;

  MI_INFO *isam_file=mrg->file[0];

  uint pack_version= (uint) isam_file->s->pack.version;

  DBUG_ENTER("compress_isam_file");



  if (!(record=(byte*) my_alloca(isam_file->s->base.reclength)))
@@ -1693,23 +1694,10 @@ static int compress_isam_file(PACK_MRG_INFO *mrg, HUFF_COUNTS *huff_counts) 
	  huff_counts[i].tree->height+huff_counts[i].length_bits;

  }

  max_calc_length/=8;

  if (max_calc_length < 254)

    pack_ref_length=1;

  else if (max_calc_length <= 65535)

    pack_ref_length=3;

  else

    pack_ref_length=4;

  pack_ref_length= calc_pack_length(pack_version, max_calc_length);

  record_count=0;

  pack_blob_length=0;

  if (isam_file->s->base.blobs)

  {

    if (mrg->max_blob_length < 254)

      pack_blob_length=1;

    else if (mrg->max_blob_length <= 65535)

      pack_blob_length=3;

    else

      pack_blob_length=4;

  }

  pack_blob_length= isam_file->s->base.blobs ?

                    calc_pack_length(pack_version, mrg->max_blob_length) : 0;

  max_pack_length=pack_ref_length+pack_blob_length;



  mrg_reset(mrg);
@@ -1865,9 +1853,10 @@ static int compress_isam_file(PACK_MRG_INFO *mrg, HUFF_COUNTS *huff_counts) 
      }

      flush_bits();

      length=(ulong) (file_buffer.pos-record_pos)-max_pack_length;

      pack_length=save_pack_length(record_pos,length);

      pack_length= save_pack_length(pack_version, record_pos, length);

      if (pack_blob_length)

	pack_length+=save_pack_length(record_pos+pack_length,tot_blob_length);

	pack_length+= save_pack_length(pack_version, record_pos + pack_length,

	                               tot_blob_length);



      /* Correct file buffer if the header was smaller */

      if (pack_length != max_pack_length)