~drizzle-trunk/drizzle/development

/* Copyright (C) 2000 MySQL 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; version 2 of the License.

   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 */

/*

  Code for handling strings with can grow dynamicly.

  Copyright Monty Program KB.

  By monty.

*/

#include "mysys_priv.h"

#include <m_string.h>

bool init_dynamic_string(DYNAMIC_STRING *str, const char *init_str,

			    size_t init_alloc, size_t alloc_increment)

{

  uint length;

  DBUG_ENTER("init_dynamic_string");

  if (!alloc_increment)

    alloc_increment=128;

  length=1;

  if (init_str && (length= strlen(init_str)+1) < init_alloc)

    init_alloc=((length+alloc_increment-1)/alloc_increment)*alloc_increment;

  if (!init_alloc)

    init_alloc=alloc_increment;

  if (!(str->str=(char*) my_malloc(init_alloc,MYF(MY_WME))))

    DBUG_RETURN(true);

  str->length=length-1;

  if (init_str)

    memcpy(str->str,init_str,length);

  str->max_length=init_alloc;

  str->alloc_increment=alloc_increment;

  DBUG_RETURN(false);

}

bool dynstr_set(DYNAMIC_STRING *str, const char *init_str)

{

  uint length=0;

  DBUG_ENTER("dynstr_set");

  if (init_str && (length= (uint) strlen(init_str)+1) > str->max_length)

  {

    str->max_length=((length+str->alloc_increment-1)/str->alloc_increment)*

      str->alloc_increment;

    if (!str->max_length)

      str->max_length=str->alloc_increment;

    if (!(str->str=(char*) my_realloc(str->str,str->max_length,MYF(MY_WME))))

      DBUG_RETURN(true);

  }

  if (init_str)

  {

    str->length=length-1;

    memcpy(str->str,init_str,length);

  }

  else

    str->length=0;

  DBUG_RETURN(false);

}

bool dynstr_realloc(DYNAMIC_STRING *str, size_t additional_size)

{

  DBUG_ENTER("dynstr_realloc");

  if (!additional_size) DBUG_RETURN(false);

  if (str->length + additional_size > str->max_length)

  {

    str->max_length=((str->length + additional_size+str->alloc_increment-1)/

		     str->alloc_increment)*str->alloc_increment;

    if (!(str->str=(char*) my_realloc(str->str,str->max_length,MYF(MY_WME))))

      DBUG_RETURN(true);

  }

  DBUG_RETURN(false);

}

bool dynstr_append(DYNAMIC_STRING *str, const char *append)

{

  return dynstr_append_mem(str,append,(uint) strlen(append));

}

bool dynstr_append_mem(DYNAMIC_STRING *str, const char *append,

			  size_t length)

{

  char *new_ptr;

  if (str->length+length >= str->max_length)

  {

    uint new_length=(str->length+length+str->alloc_increment)/

      str->alloc_increment;

    new_length*=str->alloc_increment;

    if (!(new_ptr=(char*) my_realloc(str->str,new_length,MYF(MY_WME))))

      return true;

    str->str=new_ptr;

    str->max_length=new_length;

  }

  memcpy(str->str + str->length,append,length);

  str->length+=length;

  str->str[str->length]=0;			/* Safety for C programs */

  return false;

}

bool dynstr_trunc(DYNAMIC_STRING *str, size_t n)

{

  str->length-=n;

  str->str[str->length]= '\0';

  return false;

}

/*

  Concatenates any number of strings, escapes any OS quote in the result then

  surround the whole affair in another set of quotes which is finally appended

  to specified DYNAMIC_STRING.  This function is especially useful when 

  building strings to be executed with the system() function.

  @param str Dynamic String which will have addtional strings appended.

  @param append String to be appended.

  @param ... Optional. Additional string(s) to be appended.

  @note The final argument in the list must be NullS even if no additional

  options are passed.

  @return True = Success.

*/

bool dynstr_append_os_quoted(DYNAMIC_STRING *str, const char *append, ...)

{

  const char *quote_str= "\'";

  const uint  quote_len= 1;

  bool ret= true;

  va_list dirty_text;

  ret&= dynstr_append_mem(str, quote_str, quote_len); /* Leading quote */

  va_start(dirty_text, append);

  while (append != NullS)

  {

    const char  *cur_pos= append;

    const char *next_pos= cur_pos;

    /* Search for quote in each string and replace with escaped quote */

    while(*(next_pos= strcend(cur_pos, quote_str[0])) != '\0')

    {

      ret&= dynstr_append_mem(str, cur_pos, next_pos - cur_pos);

      ret&= dynstr_append_mem(str ,"\\", 1);

      ret&= dynstr_append_mem(str, quote_str, quote_len);

      cur_pos= next_pos + 1;

    }

    ret&= dynstr_append_mem(str, cur_pos, next_pos - cur_pos);

    append= va_arg(dirty_text, char *);

  }

  va_end(dirty_text);

  ret&= dynstr_append_mem(str, quote_str, quote_len); /* Trailing quote */

  return ret;

}

void dynstr_free(DYNAMIC_STRING *str)

{

  if (str->str)

  {

    my_free(str->str,MYF(MY_WME));

    str->str=0;

  }

}