Commit 035062b2 authored by unknown's avatar unknown
Browse files

Bug#25807: LOAD DATA INFILE does not work with Pipes 

Showstopper and regression against 5.0.24.

Previously, we ignored seek() errors (see Bug#22828) and let seek()s
against pipes fail.  Now, since we check that a seek didn't fail,
and return without reading, this bug popped up.

This restores the behavior for file-ish objects that could never be 
seek()ed.


mysys/mf_iocache.c:
  If we detect early that the file is not tell()able, then we should
  assume that it's also not seek()able and therefore we should never
  set the (poorly named) "seek_not_done" flag so that we don't immedi-
  ately try to seek() when reading later.
  
  The problem was that tell() was returning -1, so when we read later, 
  we needlessly tried to seek to position  (unsigned long) -1 . 
  
  Also, if we think we're supposed to seek to a position in a file and 
  the file is un-tell()able, then abort.
parent 6f628013

BitKeeper/etc/collapsed

+2 −0
Original line number Diff line number Diff line
@@ -39,3 +39,5 @@ 
45ba4faf2oqu6eR8fqecR3LfSNcYUg

45ba5238-NKl80QVXzdGo8hO9M75Xg

45c0fdfb2mz6NdOIsLenJtf6_ZelTA

45d1ffcd-r3v8A7uh92hQaMfQM9UPQ

45d21437Vg_-i4uOWyvzYWHESXDP6A

mysys/mf_iocache.c

+35 −6
Original line number Diff line number Diff line
@@ -157,6 +157,7 @@ int init_io_cache(IO_CACHE *info, File file, uint cachesize, 
		  pbool use_async_io, myf cache_myflags)

{

  uint min_cache;

  my_off_t pos;

  my_off_t end_of_file= ~(my_off_t) 0;

  DBUG_ENTER("init_io_cache");

  DBUG_PRINT("enter",("cache: 0x%lx  type: %d  pos: %ld",
@@ -169,7 +170,25 @@ int init_io_cache(IO_CACHE *info, File file, uint cachesize, 
  info->arg = 0;

  info->alloced_buffer = 0;

  info->buffer=0;

  info->seek_not_done= test(file >= 0 && seek_offset != my_tell(file, MYF(0)));



  pos= my_tell(file, MYF(0));

  if ((pos == (my_off_t) -1) && (my_errno == ESPIPE))

  {

    /* 

      This kind of object doesn't support seek() or tell().  Don't set a flag

      that will make us again try to seek() later and fail.

    */

    info->seek_not_done= 0;

    /*

      Additionally, if we're supposed to start somewhere other than the

      the beginning of whatever this file is, then somebody made a bad

      assumption.

    */

    DBUG_ASSERT(seek_offset == 0);

  }

  else

    info->seek_not_done= test(file >= 0 && seek_offset != pos);



  info->disk_writes= 0;

#ifdef THREAD

  info->share=0;
@@ -454,13 +473,23 @@ int _my_b_read(register IO_CACHE *info, byte *Buffer, uint Count) 
  */

  if (info->seek_not_done)

  {

    if (my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)) 

        == MY_FILEPOS_ERROR)

    if ((my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)) 

        != MY_FILEPOS_ERROR))

    {

      /* No error, reset seek_not_done flag. */

      info->seek_not_done= 0;

    }

    else

    {

      /*

        If the seek failed and the error number is ESPIPE, it is because

        info->file is a pipe or socket or FIFO.  We never should have tried

        to seek on that.  See Bugs#25807 and #22828 for more info.

      */

      DBUG_ASSERT(my_errno != ESPIPE);

      info->error= -1;

      DBUG_RETURN(1);

    }

    info->seek_not_done=0;

  }



  diff_length=(uint) (pos_in_file & (IO_SIZE-1));