/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */


/* create and drop of databases */

#include "mysql_priv.h"
#include "sql_acl.h"
#include <my_dir.h>
#include <m_ctype.h>
#ifdef __WIN__
#include <direct.h>
#endif

#define MY_DB_OPT_FILE ".db.opt"

static long mysql_rm_known_files(THD *thd, MY_DIR *dirp,
				 const char *db, const char *path,
				 uint level);

/* 
    Create database options file:
    Currently databse default charset is only stored there.
*/

static int write_db_opt(THD *thd,const char *db,HA_CREATE_INFO *create,char *fn)
{
  register File file;
    char buf[256]; // Should be enough
  int error=0;

  if ((file=my_create(fn,CREATE_MODE,O_RDWR | O_TRUNC,MYF(MY_WME))) >= 0)
  {
    sprintf(buf,"default-character-set=%s\n",
		 (create && create->table_charset) ? 
		 create->table_charset->name : "DEFAULT");
    
    if (my_write(file,(byte*)buf,strlen(buf),MYF(MY_NABP+MY_WME)))
    {
      // QQ : should we send more suitable error message?
      my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
      error = -1;
      goto exit;
    }
    my_close(file,MYF(0));
  }
  else
  {
    // QQ : should we send more suitable error message?
    my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
    error = -1;
    goto exit;
  }
exit:
  return error;
}


  /* 
    Load database options file:
  */
static int load_db_opt(THD *thd,const char *db,HA_CREATE_INFO *create,char *fn)
{
  register File file;
  char buf[256]="";

  if ((file=my_open(fn,O_RDWR|O_BINARY,MYF(MY_WME))) >= 0)
  {
    int nbytes=my_read(file,(byte*)buf,sizeof(buf)-1,MYF(0));
    if ( nbytes >= 0 )
    {
      char *ln=buf;
      char *pe=buf+nbytes;

      buf[nbytes]='\0';

      for ( ln=buf; ln<pe; )
      {
	char *le,*val;
	for ( le=ln, val=0 ; le<pe ; le++ )
	{
	  switch(le[0])
	  {
	    case '=':
	      le[0]='\0';
	      val=le+1;
	      le++;
	      break;
	    case '\r':
	    case '\n':
	      le[0]='\0';
	      le++;
	      for( ; (le[0]=='\r' || le[0]=='\n') ; le++);
	      if (!strcmp(ln,"default-character-set") && val && val[0])
	      {
		create->table_charset=get_charset_by_name(val, MYF(0));
	      }
	      goto cnt;
	      break;
	  }
	}
cnt:
	ln=le;
      }
    }
    my_close(file,MYF(0));
  }
  return 0;
}

/* db-name is already validated when we come here */

int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent)
{
  char	 path[FN_REFLEN+16];
  MY_DIR *dirp;
  long result=1;
  int error = 0;
  uint create_options = create_info ? create_info->options : 0;
  
  DBUG_ENTER("mysql_create_db");
  
  VOID(pthread_mutex_lock(&LOCK_mysql_create_db));

  // do not create database if another thread is holding read lock
  if (wait_if_global_read_lock(thd,0))
  {
    error= -1;
    goto exit2;
  }

  /* Check directory */
  (void)sprintf(path,"%s/%s", mysql_data_home, db);
  unpack_dirname(path,path);			// Convert if not unix
  if ((dirp = my_dir(path,MYF(MY_DONT_SORT))))
  {
    my_dirend(dirp);
    if (!(create_options & HA_LEX_CREATE_IF_NOT_EXISTS))
    {
      my_error(ER_DB_CREATE_EXISTS,MYF(0),db);
      error = -1;
      goto exit;
    }
    result = 0;
  }
  else
  {
    strend(path)[-1]=0;				// Remove last '/' from path
    if (my_mkdir(path,0777,MYF(0)) < 0)
    {
      my_error(ER_CANT_CREATE_DB,MYF(0),db,my_errno);
      error = -1;
      goto exit;
    }
  }

  strcat(path,"/");
  unpack_dirname(path,path);
  strcat(path,MY_DB_OPT_FILE);
  if ((error=write_db_opt(thd,db,create_info,path)))
    goto exit;
  
  if (!silent)
  {
    if (!thd->query)
    {
      thd->query = path;
      thd->query_length = (uint) (strxmov(path,"create database ", db, NullS)-
				  path);
    }
    {
      mysql_update_log.write(thd,thd->query, thd->query_length);
      if (mysql_bin_log.is_open())
      {
	Query_log_event qinfo(thd, thd->query);
	mysql_bin_log.write(&qinfo);
      }
    }
    if (thd->query == path)
    {
      thd->query = 0; // just in case
      thd->query_length = 0;
    }
    send_ok(&thd->net, result);
  }

exit:
  start_waiting_global_read_lock(thd);
exit2:
  VOID(pthread_mutex_unlock(&LOCK_mysql_create_db));
  DBUG_RETURN(error);
}


/* db-name is already validated when we come here */

int mysql_alter_db(THD *thd, char *db, HA_CREATE_INFO *create_info, bool silent)
{
  char	 path[FN_REFLEN+16];
  MY_DIR *dirp;
  long result=1;
  int error = 0;
  DBUG_ENTER("mysql_create_db");
  register File file;
  uint create_options = create_info ? create_info->options : 0;

  VOID(pthread_mutex_lock(&LOCK_mysql_create_db));

  // do not alter database if another thread is holding read lock
  if (wait_if_global_read_lock(thd,0))
  {
    error= -1;
    goto exit2;
  }

  /* Check directory */
  (void)sprintf(path,"%s/%s", mysql_data_home, db);
  strcat(path,"/");
  unpack_dirname(path,path);			// Convert if not unix
  strcat(path,MY_DB_OPT_FILE);
  if ((error=write_db_opt(thd,db,create_info,path)))
    goto exit;

  /* 
     Change options if current
     database is being altered
  */
  if (thd->db && !strcmp(thd->db,db))
  {
    thd->db_charset= create_info ? create_info->table_charset : NULL;
  }

  if (!silent)
  {
    if (!thd->query)
    {
      thd->query = path;
      thd->query_length = (uint) (strxmov(path,"alter database ", db, NullS)-
				  path);
    }
    {
      mysql_update_log.write(thd,thd->query, thd->query_length);
      if (mysql_bin_log.is_open())
      {
	Query_log_event qinfo(thd, thd->query, thd->query_length);
	mysql_bin_log.write(&qinfo);
      }
    }
    if (thd->query == path)
    {
      thd->query = 0; // just in case
      thd->query_length = 0;
    }
    send_ok(&thd->net, result);
  }

exit:
  start_waiting_global_read_lock(thd);
exit2:
  VOID(pthread_mutex_unlock(&LOCK_mysql_create_db));
  DBUG_RETURN(error);
}





const char *del_exts[]= {".frm", ".BAK", ".TMD",".opt", NullS};
static TYPELIB deletable_extentions=
{array_elements(del_exts)-1,"del_exts", del_exts};

const char *known_exts[]=
{".ISM",".ISD",".ISM",".MRG",".MYI",".MYD",".db",NullS};
static TYPELIB known_extentions=
{array_elements(known_exts)-1,"known_exts", known_exts};

/*
  Drop all tables in a database.

  db-name is already validated when we come here
  If thd == 0, do not write any messages; This is useful in replication
  when we want to remove a stale database before replacing it with the new one
*/


int mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
{
  long deleted=0;
  int error = 0;
  char	path[FN_REFLEN+16];
  MY_DIR *dirp;
  DBUG_ENTER("mysql_rm_db");

  VOID(pthread_mutex_lock(&LOCK_mysql_create_db));

  // do not drop database if another thread is holding read lock
  if (wait_if_global_read_lock(thd,0))
  {
    error= -1;
    goto exit2;
  }

  (void) sprintf(path,"%s/%s",mysql_data_home,db);
  unpack_dirname(path,path);			// Convert if not unix
  /* See if the directory exists */
  if (!(dirp = my_dir(path,MYF(MY_DONT_SORT))))
  {
    if (!if_exists)
    {
      error= -1;
      my_error(ER_DB_DROP_EXISTS,MYF(0),db);
    }
    else if (!silent)
      send_ok(&thd->net,0);
    goto exit;
  }
  pthread_mutex_lock(&LOCK_open);
  remove_db_from_cache(db);
  pthread_mutex_unlock(&LOCK_open);

  error = -1;
  if ((deleted=mysql_rm_known_files(thd, dirp, db, path,0)) >= 0 && thd)
  {
    ha_drop_database(path);
    query_cache_invalidate1(db);  
    if (!silent)
    {
      if (!thd->query)
      {
	thd->query = path;
	thd->query_length = (uint) (strxmov(path,"drop database ", db, NullS)-
				    path);
      }
      mysql_update_log.write(thd, thd->query, thd->query_length);
      if (mysql_bin_log.is_open())
      {
	Query_log_event qinfo(thd, thd->query, thd->query_length);
	mysql_bin_log.write(&qinfo);
      }
      if (thd->query == path)
      {
	thd->query = 0; // just in case
	thd->query_length = 0;
      }
      send_ok(&thd->net,(ulong) deleted);
    }
    error = 0;
  }

exit:
  start_waiting_global_read_lock(thd);
exit2:
  VOID(pthread_mutex_unlock(&LOCK_mysql_create_db));

  DBUG_RETURN(error);
}

/*
  Removes files with known extensions plus all found subdirectories that
  are 2 digits (raid directories).
  thd MUST be set when calling this function!
*/

static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db,
				 const char *org_path, uint level)
{
  long deleted=0;
  ulong found_other_files=0;
  char filePath[FN_REFLEN];
  TABLE_LIST *tot_list=0, **tot_list_next;
  DBUG_ENTER("mysql_rm_known_files");
  DBUG_PRINT("enter",("path: %s", org_path));

  tot_list_next= &tot_list;

  for (uint idx=2 ;
       idx < (uint) dirp->number_off_files && !thd->killed ;
       idx++)
  {
    FILEINFO *file=dirp->dir_entry+idx;
    DBUG_PRINT("info",("Examining: %s", file->name));

    /* Check if file is a raid directory */
    if (my_isdigit(system_charset_info,file->name[0]) && 
        my_isdigit(system_charset_info,file->name[1]) &&
	!file->name[2] && !level)
    {
      char newpath[FN_REFLEN];
      MY_DIR *new_dirp;
      strxmov(newpath,org_path,"/",file->name,NullS);
      unpack_filename(newpath,newpath);
      if ((new_dirp = my_dir(newpath,MYF(MY_DONT_SORT))))
      {
	DBUG_PRINT("my",("New subdir found: %s", newpath));
	if ((mysql_rm_known_files(thd, new_dirp, NullS, newpath,1)) < 0)
	{
	  my_dirend(dirp);
	  DBUG_RETURN(-1);
	}
      }
      continue;
    }
    if (find_type(fn_ext(file->name),&deletable_extentions,1+2) <= 0)
    {
      if (find_type(fn_ext(file->name),&known_extentions,1+2) <= 0)
	found_other_files++;
      continue;
    }
    strxmov(filePath,org_path,"/",file->name,NullS);
    if (db && !my_strcasecmp(system_charset_info, 
                             fn_ext(file->name), reg_ext))
    {
      /* Drop the table nicely */
      *fn_ext(file->name)=0;			// Remove extension
      TABLE_LIST *table_list=(TABLE_LIST*)
	thd->calloc(sizeof(*table_list)+ strlen(db)+strlen(file->name)+2);
      if (!table_list)
      {
	my_dirend(dirp);
	DBUG_RETURN(-1);
      }
      table_list->db= (char*) (table_list+1);
      strmov(table_list->real_name=strmov(table_list->db,db)+1,
	     file->name);
      /* Link into list */
      (*tot_list_next)= table_list;
      tot_list_next= &table_list->next;
    }
    else
    {

      if (my_delete_with_symlink(filePath,MYF(MY_WME)))
      {
	my_dirend(dirp);
	DBUG_RETURN(-1);
      }
      deleted++;
    }
  }
  my_dirend(dirp);

  if (thd->killed ||
      (tot_list && mysql_rm_table_part2_with_lock(thd, tot_list, 1, 1)))
    DBUG_RETURN(-1);

  /*
    If the directory is a symbolic link, remove the link first, then
    remove the directory the symbolic link pointed at
  */
  if (!found_other_files)
  {
    char tmp_path[FN_REFLEN], *pos;
    char *path=unpack_filename(tmp_path,org_path);
#ifdef HAVE_READLINK
    int error;
    
    /* Remove end FN_LIBCHAR as this causes problem on Linux in readlink */
    pos=strend(path);
    if (pos > path && pos[-1] == FN_LIBCHAR)
      *--pos=0;

    if ((error=my_readlink(filePath, path, MYF(MY_WME))) < 0)
      DBUG_RETURN(-1);
    if (!error)
    {
      if (my_delete(path,MYF(!level ? MY_WME : 0)))
      {
	/* Don't give errors if we can't delete 'RAID' directory */
	if (level)
	  DBUG_RETURN(deleted);
	DBUG_RETURN(-1);
      }
      /* Delete directory symbolic link pointed at */
      path= filePath;
    }
#endif
    /* Remove last FN_LIBCHAR to not cause a problem on OS/2 */
    pos=strend(path);

    if (pos > path && pos[-1] == FN_LIBCHAR)
      *--pos=0;
    /* Don't give errors if we can't delete 'RAID' directory */
    if (rmdir(path) < 0 && !level)
    {
      my_error(ER_DB_DROP_RMDIR, MYF(0), path, errno);
      DBUG_RETURN(-1);
    }
  }
  DBUG_RETURN(deleted);
}


bool mysql_change_db(THD *thd,const char *name)
{
  int length, db_length;
  char *dbname=my_strdup((char*) name,MYF(MY_WME));
  char	path[FN_REFLEN];
  uint db_access;
  HA_CREATE_INFO create;
  
  DBUG_ENTER("mysql_change_db");

  if (!dbname || !(db_length=strip_sp(dbname)))
  {
    x_free(dbname);				/* purecov: inspected */
    send_error(&thd->net,ER_NO_DB_ERROR);	/* purecov: inspected */
    DBUG_RETURN(1);				/* purecov: inspected */
  }
  if ((db_length > NAME_LEN) || check_db_name(dbname))
  {
    net_printf(&thd->net,ER_WRONG_DB_NAME, dbname);
    x_free(dbname);
    DBUG_RETURN(1);
  }
  if (lower_case_table_names)
    casedn_str(dbname);
  DBUG_PRINT("info",("Use database: %s", dbname));
  if (test_all_bits(thd->master_access,DB_ACLS))
    db_access=DB_ACLS;
  else
    db_access= (acl_get(thd->host,thd->ip,(char*) &thd->remote.sin_addr,
			thd->priv_user,dbname) |
		thd->master_access);
  if (!(db_access & DB_ACLS) && (!grant_option || check_grant_db(thd,dbname)))
  {
    net_printf(&thd->net,ER_DBACCESS_DENIED_ERROR,
	       thd->priv_user,
	       thd->host_or_ip,
	       dbname);
    mysql_log.write(thd,COM_INIT_DB,ER(ER_DBACCESS_DENIED_ERROR),
		    thd->priv_user,
		    thd->host_or_ip,
		    dbname);
    my_free(dbname,MYF(0));
    DBUG_RETURN(1);
  }

  (void) sprintf(path,"%s/%s",mysql_data_home,dbname);
  length=unpack_dirname(path,path);		// Convert if not unix
  if (length && path[length-1] == FN_LIBCHAR)
    path[length-1]=0;				// remove ending '\'
  if (access(path,F_OK))
  {
    net_printf(&thd->net,ER_BAD_DB_ERROR,dbname);
    my_free(dbname,MYF(0));
    DBUG_RETURN(1);
  }
  send_ok(&thd->net);
  x_free(thd->db);
  thd->db=dbname;
  thd->db_length=db_length;
  thd->db_access=db_access;

  strcat(path,"/");
  unpack_dirname(path,path);
  strcat(path,MY_DB_OPT_FILE);
  bzero(&create,sizeof(create));
  load_db_opt(thd,name,&create,path);
  thd->db_charset=create.table_charset;

  DBUG_RETURN(0);
}


int mysqld_show_create_db(THD *thd,const char *name)
{
  int length, db_length;
  char *dbname=my_strdup((char*) name,MYF(MY_WME));
  char	path[FN_REFLEN];
  uint db_access;
  HA_CREATE_INFO create;
  CONVERT *convert=thd->convert_set;
  
  DBUG_ENTER("mysql_show_create_db");
  
  if (!dbname || !(db_length=strip_sp(dbname)))
  {
    x_free(dbname);				/* purecov: inspected */
    send_error(&thd->net,ER_NO_DB_ERROR);	/* purecov: inspected */
    DBUG_RETURN(1);				/* purecov: inspected */
  }
  
  if ((db_length > NAME_LEN) || check_db_name(dbname))
  {
    net_printf(&thd->net,ER_WRONG_DB_NAME, dbname);
    x_free(dbname);
    DBUG_RETURN(1);
  }
  
  if (test_all_bits(thd->master_access,DB_ACLS))
    db_access=DB_ACLS;
  else
    db_access= (acl_get(thd->host,thd->ip,(char*) &thd->remote.sin_addr,
			thd->priv_user,dbname) |
		thd->master_access);
  if (!(db_access & DB_ACLS) && (!grant_option || check_grant_db(thd,dbname)))
  {
    net_printf(&thd->net,ER_DBACCESS_DENIED_ERROR,
	       thd->priv_user,
	       thd->host_or_ip,
	       dbname);
    mysql_log.write(thd,COM_INIT_DB,ER(ER_DBACCESS_DENIED_ERROR),
		    thd->priv_user,
		    thd->host_or_ip,
		    dbname);
    my_free(dbname,MYF(0));
    DBUG_RETURN(1);
  }
  
  (void) sprintf(path,"%s/%s",mysql_data_home,dbname);
  length=unpack_dirname(path,path);		// Convert if not unix
  if (length && path[length-1] == FN_LIBCHAR)
    path[length-1]=0;				// remove ending '\'
  if (access(path,F_OK))
  {
    net_printf(&thd->net,ER_BAD_DB_ERROR,dbname);
    my_free(dbname,MYF(0));
    DBUG_RETURN(1);
  }
  
  strcat(path,"/");
  unpack_dirname(path,path);
  strcat(path,MY_DB_OPT_FILE);
  bzero(&create,sizeof(create));
  load_db_opt(thd,name,&create,path);
  
  List<Item> field_list;
  field_list.push_back(new Item_empty_string("Database",NAME_LEN));
  field_list.push_back(new Item_empty_string("Create Database",1024));
  
  if (send_fields(thd,field_list,1))
    DBUG_RETURN(1);
  
  String *packet = &thd->packet;
  packet->length(0);
  net_store_data(packet, convert, name);
  sprintf(path, "CREATE DATABASE %s", name);
  if (create.table_charset)
  {
    strcat(path," DEFAULT CHARACTER SET ");
    strcat(path,create.table_charset->name);
  }
  net_store_data(packet, convert, path);
  
  if (my_net_write(&thd->net,(char*) packet->ptr(),packet->length()))
    DBUG_RETURN(1);
  
  send_eof(&thd->net);
  
  DBUG_RETURN(0);
}