awk '
   BEGIN {
      fields_count = split("5,5,5,5,5,5,5,5,5,5,5", fsize, ",");
      FS  = "|"
      OFS = "";
   }
   function cnv_field(fld   ) {
      if (length($fld) > fsize[fld]) {
         printf("Line %d, field %d is too long (%d > %d)\n", NR, fld, length($fld), fsize[fld]) | "cat >&2";
         status = 1;
      }
      $fld = sprintf("%-5.5s", $fld);
   }
   {
      if (NF != fields_count) { 
         printf("Line %d, fields count is invalid (%d != %d)\n", NR, NF, fields_count) | "cat >&2";
         status = 1;
      }
      for (f=1; f<=NF; f++) cnv_field(f);
      print;
   }
   END {
      exit status;
   }
    '  $1 > $2

$ cat input_file
111|22|333|444|555||77|888|9999|000|1
aa|bbbbbb|cc|dd|rr|ff|ggggggg|hh|ii|jjj|hhh
xxx|yyy|zzz
$ convert.sh input_file output_file
Line 2, field 2 is too long (6 > 5)
Line 2, field 7 is too long (7 > 5)
Line 3, fields count is invalid (3 != 11)
$ echo $?
1
$ cat output_file
111  22   333  444  555       77   888  9999 000  1    
aa   bbbbbcc   dd   rr   ff   ggggghh   ii   jjj  hhh  
xxx  yyy  zzz  
$