cleanup frm creation:

* comments
* cosmetic changes, *(ptr+5) -> ptr[5]
* a couple of trivial functions -> inline
* remove unused argument from pack_header()
* create_frm() no longer creates frm file (the function used to prepare and
  fill a memory buffer and call my_create at the end. Now it only prepares
  a memory buffer). Renamed accordingly.
* don't call pack_screen twice, go for a smaller screen area in the first attempt
* remove useless calls to check_duplicate_warning()
* don't write unireg screens to .frm files
* remove make_new_entry(), it's basically dead code, always calculating
  and writing into frm the same string value. replace the function call
  with the constant string.

mysql-test/suite/archive/archive.result

@@ -12701,12 +12701,12 @@ CREATE TABLE t1(a INT, b BLOB) ENGINE=archive;
 SELECT DATA_LENGTH, AVG_ROW_LENGTH FROM
 INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME='t1' AND TABLE_SCHEMA='test';
 DATA_LENGTH	AVG_ROW_LENGTH
-8666	15
+8608	15
 INSERT INTO t1 VALUES(1, 'sampleblob1'),(2, 'sampleblob2');
 SELECT DATA_LENGTH, AVG_ROW_LENGTH FROM
 INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME='t1' AND TABLE_SCHEMA='test';
 DATA_LENGTH	AVG_ROW_LENGTH
-8700	4350
+8642	4321
 DROP TABLE t1;
 SET @save_join_buffer_size= @@join_buffer_size;
 SET @@join_buffer_size= 8192;

mysql-test/suite/archive/partition_archive.result

@@ -15,10 +15,10 @@ ENGINE = ARCHIVE;
 INSERT INTO t1 VALUES(CURRENT_DATE);
 SELECT DATA_LENGTH, INDEX_LENGTH FROM information_schema.TABLES WHERE TABLE_SCHEMA='test' AND TABLE_NAME='t1';
 DATA_LENGTH	INDEX_LENGTH
-8658	0
+8604	0
 SELECT DATA_LENGTH, INDEX_LENGTH FROM information_schema.TABLES WHERE TABLE_SCHEMA='test' AND TABLE_NAME='t1';
 DATA_LENGTH	INDEX_LENGTH
-8658	0
+8604	0
 DROP TABLE t1;
 drop database if exists db99;
 drop table if exists t1;

sql/field.h

@@ -2383,7 +2383,7 @@ public:
   /** structure with parsed options (for comparing fields in ALTER TABLE) */
   ha_field_option_struct *option_struct;
 
-  uint8 row,col,sc_length,interval_id;	// For rea_create_table
+  uint8 interval_id;                    // For rea_create_table
   uint	offset,pack_flag;
 
     /* 

sql/table.cc

@@ -594,7 +594,7 @@ enum open_frm_error open_table_def(THD *thd, TABLE_SHARE *share, uint flags)
   File file;
   MY_STAT stats;
   uchar *buf;
-  uchar head[64];
+  uchar head[FRM_HEADER_SIZE];
   char	path[FN_REFLEN];
   DBUG_ENTER("open_table_def");
   DBUG_PRINT("enter", ("table: '%s'.'%s'  path: '%s'", share->db.str,
@@ -690,6 +690,10 @@ err_not_open:
   28..29  (used to be key_info_length)
 
   They're still set, for compatibility reasons, but never read.
+
+  42..46 are unused since 5.0 (were for RAID support)
+  Also, there're few unused bytes in forminfo.
+
 */
 
 bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
@@ -739,7 +743,7 @@ bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
   if (path && writefrm(path, frm_image, frm_length))
     goto err;
 
-  if (frm_length < 64 + 288)
+  if (frm_length < FRM_HEADER_SIZE + FRM_FORMINFO_SIZE)
     goto err;
 
   new_field_pack_flag= frm_image[27];
@@ -748,11 +752,12 @@ bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
 
   /* Position of the form in the form file. */
   len = uint2korr(frm_image+4);
-  if (frm_length < 64 + len || !(pos= uint4korr(frm_image + 64 + len)))
+  if (frm_length < FRM_HEADER_SIZE + len ||
+      !(pos= uint4korr(frm_image + FRM_HEADER_SIZE + len)))
     goto err;
 
   forminfo= frm_image + pos;
-  if (forminfo + 288 >= frm_image_end)
+  if (forminfo + FRM_FORMINFO_SIZE >= frm_image_end)
     goto err;
 
   share->frm_version= frm_image[2];
@@ -766,13 +771,13 @@ bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
     share->frm_version= FRM_VER_TRUE_VARCHAR;
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
-  if (*(frm_image+61) &&
+  if (frm_image[61] &&
       !(share->default_part_db_type= 
-        ha_checktype(thd, (enum legacy_db_type) (uint) *(frm_image+61), 1, 0)))
+        ha_checktype(thd, (enum legacy_db_type) (uint) frm_image[61], 1, 0)))
     goto err;
   DBUG_PRINT("info", ("default_part_db_type = %u", frm_image[61]));
 #endif
-  legacy_db_type= (enum legacy_db_type) (uint) *(frm_image+3);
+  legacy_db_type= (enum legacy_db_type) (uint) frm_image[3];
   DBUG_ASSERT(share->db_plugin == NULL);
   /*
     if the storage engine is dynamic, no point in resolving it by its
@@ -1004,7 +1009,7 @@ bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
 
   share->reclength = uint2korr((frm_image+16));
   share->stored_rec_length= share->reclength;
-  if (*(frm_image+26) == 1)
+  if (frm_image[26] == 1)
     share->system= 1;				/* one-record-database */
 
   record_offset= (ulong) (uint2korr(frm_image+6)+
@@ -1196,7 +1201,7 @@ bool TABLE_SHARE::init_from_binary_frm_image(THD *thd, const char *path,
   share->default_values= record;
   memcpy(record, frm_image + record_offset, share->reclength);
 
-  disk_buff= frm_image + pos + 288;
+  disk_buff= frm_image + pos + FRM_FORMINFO_SIZE;
 
   share->fields= uint2korr(forminfo+258);
   pos= uint2korr(forminfo+260);   /* Length of all screens */
@@ -2705,79 +2710,7 @@ void free_field_buffers_larger_than(TABLE *table, uint32 size)
   }
 }
 
-	/* Add a new form to a form file */
-
-ulong make_new_entry(File file, uchar *fileinfo, TYPELIB *formnames,
-		     const char *newname)
-{
-  uint i,bufflength,maxlength,n_length,length,names;
-  ulong endpos,newpos;
-  uchar buff[IO_SIZE];
-  uchar *pos;
-  DBUG_ENTER("make_new_entry");
-
-  length=(uint) strlen(newname)+1;
-  n_length=uint2korr(fileinfo+4);
-  maxlength=uint2korr(fileinfo+6);
-  names=uint2korr(fileinfo+8);
-  newpos=uint4korr(fileinfo+10);
-
-  if (64+length+n_length+(names+1)*4 > maxlength)
-  {						/* Expand file */
-    newpos+=IO_SIZE;
-    int4store(fileinfo+10,newpos);
-    /* Copy from file-end */
-    endpos= (ulong) mysql_file_seek(file, 0L, MY_SEEK_END, MYF(0));
-    bufflength= (uint) (endpos & (IO_SIZE-1));	/* IO_SIZE is a power of 2 */
-
-    while (endpos > maxlength)
-    {
-      mysql_file_seek(file, (ulong) (endpos-bufflength), MY_SEEK_SET, MYF(0));
-      if (mysql_file_read(file, buff, bufflength, MYF(MY_NABP+MY_WME)))
-	DBUG_RETURN(0L);
-      mysql_file_seek(file, (ulong) (endpos-bufflength+IO_SIZE), MY_SEEK_SET,
-                      MYF(0));
-      if ((mysql_file_write(file, buff, bufflength, MYF(MY_NABP+MY_WME))))
-	DBUG_RETURN(0);
-      endpos-=bufflength; bufflength=IO_SIZE;
-    }
-    bzero(buff,IO_SIZE);			/* Null new block */
-    mysql_file_seek(file, (ulong) maxlength, MY_SEEK_SET, MYF(0));
-    if (mysql_file_write(file, buff, bufflength, MYF(MY_NABP+MY_WME)))
-	DBUG_RETURN(0L);
-    maxlength+=IO_SIZE;				/* Fix old ref */
-    int2store(fileinfo+6,maxlength);
-    for (i=names, pos= (uchar*) *formnames->type_names+n_length-1; i-- ;
-	 pos+=4)
-    {
-      endpos=uint4korr(pos)+IO_SIZE;
-      int4store(pos,endpos);
-    }
-  }
-
-  if (n_length == 1 )
-  {						/* First name */
-    length++;
-    (void) strxmov((char*) buff,"/",newname,"/",NullS);
-  }
-  else
-    (void) strxmov((char*) buff,newname,"/",NullS); /* purecov: inspected */
-  mysql_file_seek(file, 63L+(ulong) n_length, MY_SEEK_SET, MYF(0));
-  if (mysql_file_write(file, buff, (size_t) length+1, MYF(MY_NABP+MY_WME)) ||
-      (names && mysql_file_write(file,
-                                 (uchar*) (*formnames->type_names+n_length-1),
-                                 names*4, MYF(MY_NABP+MY_WME))) ||
-      mysql_file_write(file, fileinfo+10, 4, MYF(MY_NABP+MY_WME)))
-    DBUG_RETURN(0L); /* purecov: inspected */
-
-  int2store(fileinfo+8,names+1);
-  int2store(fileinfo+4,n_length+length);
-  (void) mysql_file_chsize(file, newpos, 0, MYF(MY_WME));/* Append file with '\0' */
-  DBUG_RETURN(newpos);
-} /* make_new_entry */
-
-
-	/* error message when opening a form file */
+/* error message when opening a form file */
 
 void open_table_error(TABLE_SHARE *share, enum open_frm_error error,
                       int db_errno)
@@ -2928,28 +2861,6 @@ static uint find_field(Field **fields, uchar *record, uint start, uint length)
 }
 
 
-	/* Check that the integer is in the internal */
-
-int set_zone(register int nr, int min_zone, int max_zone)
-{
-  if (nr<=min_zone)
-    return (min_zone);
-  if (nr>=max_zone)
-    return (max_zone);
-  return (nr);
-} /* set_zone */
-
-	/* Adjust number to next larger disk buffer */
-
-ulong next_io_size(register ulong pos)
-{
-  reg2 ulong offset;
-  if ((offset= pos & (IO_SIZE-1)))
-    return pos-offset+IO_SIZE;
-  return pos;
-} /* next_io_size */
-
-
 /*
   Store an SQL quoted string.
 
@@ -3012,22 +2923,13 @@ void append_unescaped(String *res, const char *pos, uint length)
 }
 
 
-	/* Create a .frm file */
-
-File create_frm(THD *thd, const char *name, const char *db,
-                const char *table, uint reclength, uchar *fileinfo,
+void prepare_frm_header(THD *thd, uint reclength, uchar *fileinfo,
                         HA_CREATE_INFO *create_info, uint keys, KEY *key_info)
 {
-  register File file;
   ulong length;
-  uchar fill[IO_SIZE];
-  int create_flags= O_RDWR | O_TRUNC;
   ulong key_comment_total_bytes= 0;
   uint i;
-  DBUG_ENTER("create_frm");
-
-  if (create_info->options & HA_LEX_CREATE_TMP_TABLE)
-    create_flags|= O_EXCL | O_NOFOLLOW;
+  DBUG_ENTER("prepare_frm_header");
 
   /* Fix this when we have new .frm files;  Current limit is 4G rows (TODO) */
   if (create_info->max_rows > UINT_MAX32)
@@ -3035,11 +2937,8 @@ File create_frm(THD *thd, const char *name, const char *db,
   if (create_info->min_rows > UINT_MAX32)
     create_info->min_rows= UINT_MAX32;
 
-  if ((file= mysql_file_create(key_file_frm,
-                               name, CREATE_MODE, create_flags, MYF(0))) >= 0)
-  {
   uint key_length, tmp_key_length, tmp, csid;
-    bzero((char*) fileinfo,64);
+  bzero((char*) fileinfo, FRM_HEADER_SIZE);
   /* header */
   fileinfo[0]=(uchar) 254;
   fileinfo[1]= 1;
@@ -3047,7 +2946,7 @@ File create_frm(THD *thd, const char *name, const char *db,
 
   fileinfo[3]= (uchar) ha_legacy_type(
         ha_checktype(thd,ha_legacy_type(create_info->db_type),0,0));
-    fileinfo[4]=1;
+  int2store(fileinfo+4,3);
   int2store(fileinfo+6,IO_SIZE);		/* Next block starts here */
   /*
     Keep in sync with pack_keys() in unireg.cc
@@ -3074,6 +2973,7 @@ File create_frm(THD *thd, const char *name, const char *db,
 
   length= next_io_size((ulong) (IO_SIZE+key_length+reclength+
                                 create_info->extra_size));
+  int2store(fileinfo+8,1);
   int4store(fileinfo+10,length);
   tmp_key_length= (key_length < 0xffff) ? key_length : 0xffff;
   int2store(fileinfo+14,tmp_key_length);
@@ -3110,26 +3010,8 @@ File create_frm(THD *thd, const char *name, const char *db,
     61 for default_part_db_type
   */
   int2store(fileinfo+62, create_info->key_block_size);
-    bzero(fill,IO_SIZE);
-    for (; length > IO_SIZE ; length-= IO_SIZE)
-    {
-      if (mysql_file_write(file, fill, IO_SIZE, MYF(MY_WME | MY_NABP)))
-      {
-        (void) mysql_file_close(file, MYF(0));
-        (void) mysql_file_delete(key_file_frm, name, MYF(0));
-	return(-1);
-      }
-    }
-  }
-  else
-  {
-    if (my_errno == ENOENT)
-      my_error(ER_BAD_DB_ERROR,MYF(0),db);
-    else
-      my_error(ER_CANT_CREATE_TABLE,MYF(0),table,my_errno);
-  }
-  DBUG_RETURN(file);
-} /* create_frm */
+  DBUG_VOID_RETURN;
+} /* prepare_fileinfo */
 
 
 void update_create_info_from_table(HA_CREATE_INFO *create_info, TABLE *table)

sql/table.h

@@ -2490,17 +2490,28 @@ bool get_field(MEM_ROOT *mem, Field *field, class String *res);
 int closefrm(TABLE *table, bool free_share);
 void free_blobs(TABLE *table);
 void free_field_buffers_larger_than(TABLE *table, uint32 size);
-int set_zone(int nr,int min_zone,int max_zone);
 ulong get_form_pos(File file, uchar *head, TYPELIB *save_names);
-ulong make_new_entry(File file,uchar *fileinfo,TYPELIB *formnames,
-		     const char *newname);
-ulong next_io_size(ulong pos);
 void append_unescaped(String *res, const char *pos, uint length);
-File create_frm(THD *thd, const char *name, const char *db,
-                const char *table, uint reclength, uchar *fileinfo,
+void prepare_frm_header(THD *thd, uint reclength, uchar *fileinfo,
                         HA_CREATE_INFO *create_info, uint keys, KEY *key_info);
 char *fn_rext(char *name);
 
+/* Check that the integer is in the internal */
+static inline int set_zone(int nr,int min_zone,int max_zone)
+{
+  if (nr <= min_zone)
+    return min_zone;
+  if (nr >= max_zone)
+    return max_zone;
+  return nr;
+}
+
+/* Adjust number to next larger disk buffer */
+static inline ulong next_io_size(ulong pos)
+{
+  return MY_ALIGN(pos, IO_SIZE);
+}
+
 /* performance schema */
 extern LEX_STRING PERFORMANCE_SCHEMA_DB_NAME;
 

sql/unireg.cc

@@ -27,7 +27,6 @@
 #include "sql_priv.h"
 #include "unireg.h"
 #include "sql_partition.h"                      // struct partition_info
-#include "sql_table.h"                          // check_duplicate_warning
 #include "sql_class.h"                  // THD, Internal_error_handler
 #include "create_options.h"
 #include <m_ctype.h>
@@ -38,54 +37,11 @@
 /* threshold for safe_alloca */
 #define ALLOCA_THRESHOLD       2048
 
-static uchar * pack_screens(List<Create_field> &create_fields,
-			    uint *info_length, uint *screens, bool small_file);
-static uint pack_keys(uchar *keybuff,uint key_count, KEY *key_info,
-                      ulong data_offset);
-static bool pack_header(uchar *forminfo,enum legacy_db_type table_type,
-			List<Create_field> &create_fields,
-			uint info_length, uint screens, uint table_options,
-			ulong data_offset, handler *file);
+static uint pack_keys(uchar *,uint, KEY *, ulong);
+static bool pack_header(uchar *, List<Create_field> &, uint, ulong, handler *);
 static uint get_interval_id(uint *,List<Create_field> &, Create_field *);
-static bool pack_fields(File file, List<Create_field> &create_fields,
-                        ulong data_offset);
-static bool make_empty_rec(THD *thd, int file, uint table_options,
-			   List<Create_field> &create_fields,
-			   uint reclength, ulong data_offset);
-
-/**
-  An interceptor to hijack ER_TOO_MANY_FIELDS error from
-  pack_screens and retry again without UNIREG screens.
-
-  XXX: what is a UNIREG  screen?
-*/
-
-struct Pack_header_error_handler: public Internal_error_handler
-{
-  virtual bool handle_condition(THD *thd,
-                                uint sql_errno,
-                                const char* sqlstate,
-                                MYSQL_ERROR::enum_warning_level level,
-                                const char* msg,
-                                MYSQL_ERROR ** cond_hdl);
-  bool is_handled;
-  Pack_header_error_handler() :is_handled(FALSE) {}
-};
-
-
-bool
-Pack_header_error_handler::
-handle_condition(THD *,
-                 uint sql_errno,
-                 const char*,
-                 MYSQL_ERROR::enum_warning_level,
-                 const char*,
-                 MYSQL_ERROR ** cond_hdl)
-{
-  *cond_hdl= NULL;
-  is_handled= (sql_errno == ER_TOO_MANY_FIELDS);
-  return is_handled;
-}
+static bool pack_fields(File, List<Create_field> &, ulong);
+static bool make_empty_rec(THD *, int, uint, List<Create_field> &, uint, ulong);
 
 /*
   Create a frm (table definition) file
@@ -115,25 +71,20 @@ bool mysql_create_frm(THD *thd, const char *file_name,
 		      handler *db_file)
 {
   LEX_STRING str_db_type;
-  uint reclength, info_length, screens, key_info_length, maxlength, tmp_len, i;
+  uint reclength, key_info_length, maxlength, tmp_len, i;
   ulong key_buff_length;
   File file;
   ulong filepos, data_offset;
   uint options_len;
-  uchar fileinfo[64],forminfo[288],*keybuff;
-  uchar *screen_buff;
+  uchar fileinfo[FRM_HEADER_SIZE],forminfo[FRM_FORMINFO_SIZE],*keybuff;
   char buff[128];
 #ifdef WITH_PARTITION_STORAGE_ENGINE
   partition_info *part_info= thd->work_part_info;
 #endif
-  Pack_header_error_handler pack_header_error_handler;
   int error;
   DBUG_ENTER("mysql_create_frm");
 
   DBUG_ASSERT(*fn_rext((char*)file_name)); // Check .frm extension
-
-  if (!(screen_buff=pack_screens(create_fields,&info_length,&screens,0)))
-    DBUG_RETURN(1);
   DBUG_ASSERT(db_file != NULL);
 
  /* If fixed row records, we need one bit to check for deleted rows */
@@ -141,32 +92,12 @@ bool mysql_create_frm(THD *thd, const char *file_name,
     create_info->null_bits++;
   data_offset= (create_info->null_bits + 7) / 8;
 
-  thd->push_internal_handler(&pack_header_error_handler);
-
-  error= pack_header(forminfo, ha_legacy_type(create_info->db_type),
-                     create_fields,info_length,
-                     screens, create_info->table_options,
+  error= pack_header(forminfo, create_fields, create_info->table_options,
                      data_offset, db_file);
 
-  thd->pop_internal_handler();
-
   if (error)
-  {
-    my_free(screen_buff);
-    if (! pack_header_error_handler.is_handled)
     DBUG_RETURN(1);
 
-    // Try again without UNIREG screens (to get more columns)
-    if (!(screen_buff=pack_screens(create_fields,&info_length,&screens,1)))
-      DBUG_RETURN(1);
-    if (pack_header(forminfo, ha_legacy_type(create_info->db_type),
-                    create_fields,info_length,
-		    screens, create_info->table_options, data_offset, db_file))
-    {
-      my_free(screen_buff);
-      DBUG_RETURN(1);
-    }
-  }
   reclength=uint2korr(forminfo+266);
 
   /* Calculate extra data segment length */
@@ -244,14 +175,11 @@ bool mysql_create_frm(THD *thd, const char *file_name,
     {
       my_error(ER_TOO_LONG_TABLE_COMMENT, MYF(0),
                real_table_name, static_cast<ulong>(TABLE_COMMENT_MAXLEN));
-      my_free(screen_buff);
       DBUG_RETURN(1);
     }
     char warn_buff[MYSQL_ERRMSG_SIZE];
     my_snprintf(warn_buff, sizeof(warn_buff), ER(ER_TOO_LONG_TABLE_COMMENT),
                 real_table_name, static_cast<ulong>(TABLE_COMMENT_MAXLEN));
-    /* do not push duplicate warnings */
-    if (!check_duplicate_warning(current_thd, warn_buff, strlen(warn_buff)))
     push_warning(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                  ER_TOO_LONG_TABLE_COMMENT, warn_buff);
     create_info->comment.length= tmp_len;
@@ -266,32 +194,43 @@ bool mysql_create_frm(THD *thd, const char *file_name,
     forminfo[46]=255;
     create_info->extra_size+= 2 + create_info->comment.length;
   }
-  else{
+  else
+  {
     strmake((char*) forminfo+47, create_info->comment.str ?
             create_info->comment.str : "", create_info->comment.length);
     forminfo[46]=(uchar) create_info->comment.length;
   }
 
-  if ((file=create_frm(thd, file_name, db, table, reclength, fileinfo,
-		       create_info, keys, key_info)) < 0)
-  {
-    my_free(screen_buff);
-    DBUG_RETURN(1);
-  }
+  prepare_frm_header(thd, reclength, fileinfo, create_info, keys, key_info);
 
   key_buff_length= uint4korr(fileinfo+47);
   keybuff=(uchar*) my_malloc(key_buff_length, MYF(MY_THREAD_SPECIFIC));
   key_info_length= pack_keys(keybuff, keys, key_info, data_offset);
 
-  /*
-    Ensure that there are no forms in this newly created form file.
-    Even if the form file exists, create_frm must truncate it to
-    ensure one form per form file.
-  */
-  DBUG_ASSERT(uint2korr(fileinfo+8) == 0);
+  int create_flags= O_RDWR | O_TRUNC;
+  if (create_info->options & HA_LEX_CREATE_TMP_TABLE)
+    create_flags|= O_EXCL | O_NOFOLLOW;
 
-  if (!(filepos= make_new_entry(file, fileinfo, NULL, "")))
+  file= mysql_file_create(key_file_frm, file_name,
+                          CREATE_MODE, create_flags, MYF(0));
+  if (file < 0)
+  {
+    if (my_errno == ENOENT)
+      my_error(ER_BAD_DB_ERROR,MYF(0),db);
+    else
+      my_error(ER_CANT_CREATE_TABLE,MYF(0),table,my_errno);
+    my_free(keybuff);
+    DBUG_RETURN(1);
+  }
+
+  //========================
+  filepos= uint4korr(fileinfo+10);
+  mysql_file_seek(file, FRM_HEADER_SIZE, MY_SEEK_SET, MYF(0));
+  if (mysql_file_write(file, (uchar*)"//", 3, MYF(MY_NABP+MY_WME)) ||
+      mysql_file_write(file, fileinfo+10, 4, MYF(MY_NABP+MY_WME)))
     goto err;
+  //========================
+
   maxlength=(uint) next_io_size((ulong) (uint2korr(forminfo)+1000));
   int2store(forminfo+2,maxlength);
   int4store(fileinfo+10,(ulong) (filepos+maxlength));
@@ -308,7 +247,7 @@ bool mysql_create_frm(THD *thd, const char *file_name,
 #endif
   int2store(fileinfo+59,db_file->extra_rec_buf_length());
 
-  if (mysql_file_pwrite(file, fileinfo, 64, 0L, MYF_RW) ||
+  if (mysql_file_pwrite(file, fileinfo, FRM_HEADER_SIZE, 0L, MYF_RW) ||
       mysql_file_pwrite(file, keybuff, key_info_length,
                         (ulong) uint2korr(fileinfo+6), MYF_RW))
     goto err;
@@ -388,12 +327,10 @@ bool mysql_create_frm(THD *thd, const char *file_name,
   }
 
   mysql_file_seek(file, filepos, MY_SEEK_SET, MYF(0));
-  if (mysql_file_write(file, forminfo, 288, MYF_RW) ||
-      mysql_file_write(file, screen_buff, info_length, MYF_RW) ||
+  if (mysql_file_write(file, forminfo, FRM_FORMINFO_SIZE, MYF_RW) ||
       pack_fields(file, create_fields, data_offset))
     goto err;
 
-  my_free(screen_buff);
   my_free(keybuff);
 
   if (opt_sync_frm && !(create_info->options & HA_LEX_CREATE_TMP_TABLE) &&
@@ -423,7 +360,6 @@ bool mysql_create_frm(THD *thd, const char *file_name,
   DBUG_RETURN(0);
 
 err:
-  my_free(screen_buff);
   my_free(keybuff);
 err2:
   (void) mysql_file_close(file, MYF(MY_WME));
@@ -486,82 +422,6 @@ err_handler:
 } /* rea_create_table */
 
 
-	/* Pack screens to a screen for save in a form-file */
-
-static uchar *pack_screens(List<Create_field> &create_fields,
-                           uint *info_length, uint *screens,
-                           bool small_file)
-{
-  reg1 uint i;
-  uint row,start_row,end_row,fields_on_screen;
-  uint length,cols;
-  uchar *info,*pos,*start_screen;
-  uint fields=create_fields.elements;
-  List_iterator<Create_field> it(create_fields);
-  DBUG_ENTER("pack_screens");
-
-  start_row=4; end_row=22; cols=80; fields_on_screen=end_row+1-start_row;
-
-  *screens=(fields-1)/fields_on_screen+1;
-  length= (*screens) * (SC_INFO_LENGTH+ (cols>> 1)+4);
-
-  Create_field *field;
-  while ((field=it++))
-    length+=(uint) strlen(field->field_name)+1+TE_INFO_LENGTH+cols/2;
-
-  if (!(info=(uchar*) my_malloc(length,MYF(MY_WME | MY_THREAD_SPECIFIC))))
-    DBUG_RETURN(0);
-
-  start_screen=0;
-  row=end_row;
-  pos=info;
-  it.rewind();
-  for (i=0 ; i < fields ; i++)
-  {
-    Create_field *cfield=it++;
-    if (row++ == end_row)
-    {
-      if (i)
-      {
-	length=(uint) (pos-start_screen);
-	int2store(start_screen,length);
-	start_screen[2]=(uchar) (fields_on_screen+1);
-	start_screen[3]=(uchar) (fields_on_screen);
-      }
-      row=start_row;
-      start_screen=pos;
-      pos+=4;
-      pos[0]= (uchar) start_row-2;	/* Header string */
-      pos[1]= (uchar) (cols >> 2);
-      pos[2]= (uchar) (cols >> 1) +1;
-      strfill((char *) pos+3,(uint) (cols >> 1),' ');
-      pos+=(cols >> 1)+4;
-    }
-    length=(uint) strlen(cfield->field_name);
-    if (length > cols-3)
-      length=cols-3;
-
-    if (!small_file)
-    {
-      pos[0]=(uchar) row;
-      pos[1]=0;
-      pos[2]=(uchar) (length+1);
-      pos=(uchar*) strmake((char*) pos+3,cfield->field_name,length)+1;
-    }
-    cfield->row=(uint8) row;
-    cfield->col=(uint8) (length+1);
-    cfield->sc_length=(uint8) min(cfield->length,cols-(length+2));
-  }
-  length=(uint) (pos-start_screen);
-  int2store(start_screen,length);
-  start_screen[2]=(uchar) (row-start_row+2);
-  start_screen[3]=(uchar) (row-start_row+1);
-
-  *info_length=(uint) (pos-info);
-  DBUG_RETURN(info);
-} /* pack_screens */
-
-
 	/* Pack keyinfo and keynames to keybuff for save in form-file. */
 
 static uint pack_keys(uchar *keybuff, uint key_count, KEY *keyinfo,
@@ -647,10 +507,8 @@ static uint pack_keys(uchar *keybuff, uint key_count, KEY *keyinfo,
 
 	/* Make formheader */
 
-static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
-			List<Create_field> &create_fields,
-                        uint info_length, uint screens, uint table_options,
-                        ulong data_offset, handler *file)
+static bool pack_header(uchar *forminfo, List<Create_field> &create_fields,
+                        uint table_options, ulong data_offset, handler *file)
 {
   uint length,int_count,int_length,no_empty, int_parts;
   uint time_stamp_pos,null_fields;
@@ -693,8 +551,6 @@ static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
       my_snprintf(warn_buff, sizeof(warn_buff), ER(ER_TOO_LONG_FIELD_COMMENT),
                   field->field_name,
                   static_cast<ulong>(COLUMN_COMMENT_MAXLEN));
-      /* do not push duplicate warnings */
-      if (!check_duplicate_warning(current_thd, warn_buff, strlen(warn_buff)))
       push_warning(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                    ER_TOO_LONG_FIELD_COMMENT, warn_buff);
       field->comment.length= tmp_len;
@@ -808,7 +664,7 @@ static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
   }
   /* Hack to avoid bugs with small static rows in MySQL */
   reclength=max(file->min_record_length(table_options),reclength);
-  if (info_length+(ulong) create_fields.elements*FCOMP+288+
+  if ((ulong) create_fields.elements*FCOMP+FRM_FORMINFO_SIZE+
       n_length+int_length+com_length+vcol_info_length > 65535L || 
       int_count > 255)
   {
@@ -816,13 +672,13 @@ static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
     DBUG_RETURN(1);
   }
 
-  bzero((char*)forminfo,288);
-  length=(info_length+create_fields.elements*FCOMP+288+n_length+int_length+
+  bzero((char*)forminfo,FRM_FORMINFO_SIZE);
+  length=(create_fields.elements*FCOMP+FRM_FORMINFO_SIZE+n_length+int_length+
 	  com_length+vcol_info_length);
   int2store(forminfo,length);
-  forminfo[256] = (uint8) screens;
+  forminfo[256] = 0;
   int2store(forminfo+258,create_fields.elements);
-  int2store(forminfo+260,info_length);
+  int2store(forminfo+260,0);
   int2store(forminfo+262,totlength);
   int2store(forminfo+264,no_empty);
   int2store(forminfo+266,reclength);
@@ -836,7 +692,6 @@ static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
   int2store(forminfo+282,null_fields);
   int2store(forminfo+284,com_length);
   int2store(forminfo+286,vcol_info_length);
-  /* forminfo+288 is free to use for additional information */
   DBUG_RETURN(0);
 } /* pack_header */
 
@@ -889,9 +744,6 @@ static bool pack_fields(File file, List<Create_field> &create_fields,
   {
     uint recpos;
     uint cur_vcol_expr_len= 0;
-    buff[0]= (uchar) field->row;
-    buff[1]= (uchar) field->col;
-    buff[2]= (uchar) field->sc_length;
     int2store(buff+3, field->length);
     /* The +1 is here becasue the col offset in .frm file have offset 1 */
     recpos= field->offset+1 + (uint) data_offset;

sql/unireg.h

@@ -179,6 +179,9 @@ int rea_create_table(THD *thd, const char *path,
                      uint key_count,KEY *key_info,
                      handler *file);
 
+#define FRM_HEADER_SIZE 64
+#define FRM_FORMINFO_SIZE 288
+
 static inline bool is_binary_frm_header(uchar *head)
 {
   return head[0] == 254