/* d4open.c   (c)Copyright Sequiter Software Inc., 1990-1994.  All rights reserved. */

#include "d4all.h"
#ifndef S4UNIX
#ifdef __TURBOC__
#pragma hdrstop
#endif
#endif

#ifdef S4OFF_MEMO
extern char f4memo_null_char ;
#endif

DATA4 *S4FUNCTION d4open( CODE4 *c4, char *name )
{
  int rc, i_fields, i_memo ;
  unsigned field_data_len, count ;
  char name_buf[258], field_buf[2], *info ;
  DATA4 *d4 ;
  DATA4HEADER_FULL full_header ;
  INDEX4 *i4 ;
  FIELD4IMAGE *image ;

#ifdef S4VBASIC
  if ( c4parm_check( c4, 1, E4_D4OPEN ) )
    return 0 ;
#endif

  if ( c4 == 0 || name == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4OPEN ) ;
#else
  return 0 ;
#endif

  if ( c4->error_code < 0 )
    return 0 ;

#ifdef S4DEBUG
  if ( c4->debug_int != 0x5281 )
    e4severe( e4result, E4_RESULT_D4I ) ;

#ifndef S4WIN32
  u4name_piece( name_buf, sizeof( name_buf ), name, 0, 0 ) ;
  if ( d4data( c4, name_buf ) )
  {
    e4( c4, e4info, E4_INFO_DAO ) ;
    return 0 ;
  }
#endif
#endif

  if ( c4->data_memory == 0 )
  {
    c4->data_memory = mem4create( c4, c4->mem_start_data, sizeof(DATA4), c4->mem_expand_data, 0 ) ;
    if ( c4->data_memory == 0 )
    {
      e4( c4, e4memory, 0 ) ;
      return 0 ;
    }
  }
  d4 = (DATA4 *) mem4alloc( c4->data_memory ) ;
  if ( d4 == 0 )
  {
    e4(  c4, e4memory, 0 ) ;
    return 0 ;
  }

#ifdef S4VBASIC
  d4->debug_int = 0x5281 ;
#endif
  d4->code_base = c4 ;

#ifndef S4SINGLE
  d4->locks = &d4->locked_record ;
  d4->n_locks = 1 ;
#endif
  d4->memo_file.file.hand = -1 ;

  u4ncpy( name_buf, name, sizeof(name_buf) ) ;
#ifdef S4UNIX
  u4name_ext( name_buf, sizeof(name_buf), "dbf", 0 ) ;
#else
  u4name_ext( name_buf, sizeof(name_buf), "DBF", 0 ) ;
#endif

  rc = file4open( &d4->file, c4, name_buf, 1 ) ;
  if ( rc )
  {
    d4close( d4 ) ;
    return 0 ;
  }
  l4add( &c4->data_list, &d4->link ) ;

  u4name_piece( d4->alias, sizeof(d4->alias), name_buf, 0,0 ) ;

  if ( file4read_all( &d4->file, 0L, &full_header, sizeof( full_header ) ) < 0 )
  {
    d4close( d4 ) ;
    return 0 ;
  }

#ifdef S4BYTE_SWAP
  full_header.num_recs = x4reverse_long( (void *)&full_header.num_recs ) ;
  full_header.header_len = x4reverse_short( (void *)&full_header.header_len ) ;
  full_header.record_len = x4reverse_short( (void *)&full_header.record_len ) ;
#endif

#ifdef S4DEMO
  if ( full_header.num_recs > 200L)
  {
    e4( c4, e4demo, 0 ) ;
    d4close(d4) ;
    return 0 ;
  }
#endif

#ifdef S4DEBUG
  if ( full_header.num_recs < 0L || full_header.num_recs > ( 1 +  ( file4len ( &d4->file )  - full_header.header_len ) / full_header.record_len ) )
    e4severe( e4info, E4_DATA_COR ) ;
#endif

  memcpy( (void *)&d4->version, (void *)&full_header.version, (4+(sizeof(S4LONG))+(sizeof(short))) ) ;

  d4->num_recs = -1L ;
  d4->has_mdx = full_header.has_mdx ;

  field_data_len = full_header.header_len-sizeof(full_header) ;
  if ( full_header.header_len <= sizeof(full_header) )
  {
    e4( c4, e4data, d4->file.name ) ;
    d4close(d4) ;
    return 0 ;
  }

  info = (char *) u4alloc_free( c4, field_data_len ) ;
  if ( info == 0 )
  {
    e4( c4, e4memory, 0 ) ;
    d4close(d4) ;
    return 0 ;
  }

  if ( file4read_all( &d4->file, (long) sizeof(full_header), info,field_data_len) < 0 )
  {
    u4free(info) ;
    e4( c4, e4data, 0 ) ;
    d4close(d4) ;
    return 0 ;
  }

  /* count the number of fields */
  for (count=0; count < field_data_len; count+= 32 )
    if ( info[count] == 0xD )  break ;
  d4->n_fields = (int) (count/32) ;
  if ( field_data_len/32 < (unsigned) d4->n_fields )
  {
    u4free(info) ;
    e4( c4, e4data, d4->file.name ) ;
    d4close(d4) ;
    return 0 ;
  }

  d4->fields = (FIELD4 *) u4alloc_free( c4, sizeof(FIELD4) * (long) d4->n_fields ) ;
  if ( d4->fields == 0 )  e4( c4, e4memory, 0 ) ;

  d4->record_width = 1 ;

  if ( !(c4->error_code < 0)  )
    for ( i_fields = 0; i_fields < d4->n_fields; i_fields++ )
    {
      image = (FIELD4IMAGE *) (info+ i_fields*32) ;
      u4ncpy( d4->fields[i_fields].name, image->name, sizeof(d4->fields->name) ) ;

      u4ncpy( field_buf, &image->type, 2 ) ;
      c4upper( field_buf ) ;
      d4->fields[i_fields].type = *field_buf ;

      if ( d4->fields[i_fields].type == 'N' || d4->fields[i_fields].type == 'F')
      {
        d4->fields[i_fields].len = image->len ;
        d4->fields[i_fields].dec = image->dec ;
      }
      else
      {
        if ( d4->fields[i_fields].type == 'L' || d4->fields[i_fields].type == 'D' || d4->fields[i_fields].type == 'M' || d4->fields[i_fields].type == 'G' ||
            d4->fields[i_fields].type == 'B' )
          d4->fields[i_fields].len = image->len ;
        else
          d4->fields[i_fields].len = image->len + (image->dec << 8) ;
        d4->fields[i_fields].dec = 0 ;
      }

      if ( d4->fields[i_fields].type == 'M' || d4->fields[i_fields].type == 'G' || d4->fields[i_fields].type == 'B' )
      {
        d4->n_fields_memo++ ;
#ifdef S4MEMO_OFF
        d4->fields[i_fields].memo = (F4MEMO *)&f4memo_null_char ;
#endif
      }

#ifdef S4VBASIC
      d4->fields[i_fields].debug_int = 0x5281 ;
#endif
      d4->fields[i_fields].offset = d4->record_width ;
      d4->record_width += d4->fields[i_fields].len ;
      d4->fields[i_fields].data = d4 ;
    }

  u4free( info ) ;

#ifndef S4MEMO_OFF
  if ( d4->n_fields_memo > 0  &&  ! (c4->error_code< 0) )
  {
    i_memo = 0 ;

    d4->fields_memo = (F4MEMO *)u4alloc_free( c4, (long)sizeof(F4MEMO) * d4->n_fields_memo ) ;
    if ( d4->fields_memo == 0 )
      e4( c4, e4memory, 0 ) ;
    else
      for ( i_fields = 0; i_fields < d4->n_fields; i_fields++ )
        if ( d4->fields[i_fields].type == 'M' || d4->fields[i_fields].type == 'G' || d4->fields[i_fields].type == 'B' )
        {
          d4->fields[i_fields].memo = d4->fields_memo+i_memo ;
          d4->fields_memo[i_memo].status = 1 ;
          d4->fields_memo[i_memo].field = d4->fields+i_fields ;
          i_memo++ ;
        }
  }
#endif

  if ( d4->record_width != full_header.record_len  &&  ! (c4->error_code<0) )
    e4( c4, e4data, d4->file.name ) ;

  if ( c4->error_code < 0 )
  {
    d4close(d4) ;
    return 0 ;
  }

  d4->record = (char *) u4alloc_free( c4, d4->record_width + 1 ) ;
  d4->record_old = (char *) u4alloc_free( c4, d4->record_width+1 ) ;
  if ( d4->record == 0  ||  d4->record_old == 0 )
  {
    e4( c4, e4memory, 0 ) ;
    d4close(d4) ;
    return 0 ;
  }

  memset( d4->record, ' ', d4->record_width ) ;
  memset( d4->record_old, ' ', d4->record_width ) ;

  d4->rec_num = d4->rec_num_old = -1 ;

#ifndef S4OPTIMIZE_OFF
  file4optimize( &d4->file, c4->optimize, OPT4DBF ) ;
#endif

#ifndef S4INDEX_OFF
#ifdef N4OTHER
  if ( c4->auto_open )
  {
    i4 = i4open( d4, 0 ) ;
    if ( i4 == 0 )
    {
      d4close(d4) ;
      return 0 ;
    }
  }
#else
  if ( d4->has_mdx && c4->auto_open )
  {
    i4 = i4open( d4, 0 ) ;
    if ( i4 == 0 )
    {
      d4close(d4) ;
      return 0 ;
    }
#ifdef S4MDX
    if ( !i4->header.is_production )
      i4close(i4);
#endif
  }
#endif
#endif

#ifndef S4MEMO_OFF
  if ( d4->version & 0x80 )
  {
#ifdef S4MFOX
#ifdef S4UNIX
    u4name_ext( name_buf, sizeof(name_buf), "fpt", 1 ) ;
#else
    u4name_ext( name_buf, sizeof(name_buf), "FPT", 1 ) ;
#endif
#else
#ifdef S4UNIX
    u4name_ext( name_buf, sizeof(name_buf), "dbt", 1 ) ;
#else
    u4name_ext( name_buf, sizeof(name_buf), "DBT", 1 ) ;
#endif
#endif
    if ( memo4file_open( &d4->memo_file, d4, name_buf ) < 0 )
    {
      d4close(d4) ;
      return 0 ;
    }
  }
#endif

  return d4 ;
}

#ifdef S4VB_DOS

DATA4 * d4open_v( CODE4 *c4, char *name )
{
  return d4open( c4, c4str(name) ) ;
}

#endif