~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 */

/* This file is originally from the mysql distribution. Coded by monty */

#ifdef USE_PRAGMA_INTERFACE

#pragma interface			/* gcc class implementation */

#endif

#ifndef NOT_FIXED_DEC

#define NOT_FIXED_DEC			31

#endif

class String;

int sortcmp(const String *a,const String *b, CHARSET_INFO *cs);

String *copy_if_not_alloced(String *a,String *b,uint32 arg_length);

uint32 copy_and_convert(char *to, uint32 to_length, CHARSET_INFO *to_cs,

			const char *from, uint32 from_length,

			CHARSET_INFO *from_cs, uint *errors);

class String

{

  char *Ptr;

  uint32 str_length,Alloced_length;

  bool alloced;

  CHARSET_INFO *str_charset;

public:

  String()

  { 

    Ptr=0; str_length=Alloced_length=0; alloced=0; 

    str_charset= &my_charset_bin; 

  }

  String(uint32 length_arg)

  { 

    alloced=0; Alloced_length=0; (void) real_alloc(length_arg); 

    str_charset= &my_charset_bin;

  }

  String(const char *str, CHARSET_INFO *cs)

  { 

    Ptr=(char*) str; str_length=(uint) strlen(str); Alloced_length=0; alloced=0;

    str_charset=cs;

  }

  String(const char *str,uint32 len, CHARSET_INFO *cs)

  { 

    Ptr=(char*) str; str_length=len; Alloced_length=0; alloced=0;

    str_charset=cs;

  }

  String(char *str,uint32 len, CHARSET_INFO *cs)

  { 

    Ptr=(char*) str; Alloced_length=str_length=len; alloced=0;

    str_charset=cs;

  }

  String(const String &str)

  { 

    Ptr=str.Ptr ; str_length=str.str_length ;

    Alloced_length=str.Alloced_length; alloced=0; 

    str_charset=str.str_charset;

  }

  static void *operator new(size_t size, MEM_ROOT *mem_root)

  { return (void*) alloc_root(mem_root, (uint) size); }

  static void operator delete(void *ptr_arg __attribute__((__unused__)),

                              size_t size __attribute__((__unused__)))

  { /* never called */ }

  static void operator delete(void *ptr_arg __attribute__((__unused__)),

                              MEM_ROOT *mem_root __attribute__((__unused__)))

  { /* never called */ }

  ~String() { free(); }

  inline void set_charset(CHARSET_INFO *charset_arg)

  { str_charset= charset_arg; }

  inline CHARSET_INFO *charset() const { return str_charset; }

  inline uint32 length() const { return str_length;}

  inline uint32 alloced_length() const { return Alloced_length;}

  inline char& operator [] (uint32 i) const { return Ptr[i]; }

  inline void length(uint32 len) { str_length=len ; }

  inline bool is_empty() { return (str_length == 0); }

  inline void mark_as_const() { Alloced_length= 0;}

  inline const char *ptr() const { return Ptr; }

  inline char *c_ptr()

  {

    if (!Ptr || Ptr[str_length])		/* Should be safe */

      (void) realloc(str_length);

    return Ptr;

  }

  inline char *c_ptr_quick()

  {

    if (Ptr && str_length < Alloced_length)

      Ptr[str_length]=0;

    return Ptr;

  }

  inline char *c_ptr_safe()

  {

    if (Ptr && str_length < Alloced_length)

      Ptr[str_length]=0;

    else

      (void) realloc(str_length);

    return Ptr;

  }

  void set(String &str,uint32 offset,uint32 arg_length)

  {

    DBUG_ASSERT(&str != this);

    free();

    Ptr=(char*) str.ptr()+offset; str_length=arg_length; alloced=0;

    if (str.Alloced_length)

      Alloced_length=str.Alloced_length-offset;

    else

      Alloced_length=0;

    str_charset=str.str_charset;

  }

  inline void set(char *str,uint32 arg_length, CHARSET_INFO *cs)

  {

    free();

    Ptr=(char*) str; str_length=Alloced_length=arg_length ; alloced=0;

    str_charset=cs;

  }

  inline void set(const char *str,uint32 arg_length, CHARSET_INFO *cs)

  {

    free();

    Ptr=(char*) str; str_length=arg_length; Alloced_length=0 ; alloced=0;

    str_charset=cs;

  }

  bool set_ascii(const char *str, uint32 arg_length);

  inline void set_quick(char *str,uint32 arg_length, CHARSET_INFO *cs)

  {

    if (!alloced)

    {

      Ptr=(char*) str; str_length=Alloced_length=arg_length;

    }

    str_charset=cs;

  }

  bool set(longlong num, CHARSET_INFO *cs);

  bool set(ulonglong num, CHARSET_INFO *cs);

  bool set(double num,uint decimals, CHARSET_INFO *cs);

  /*

    PMG 2004.11.12

    This is a method that works the same as perl's "chop". It simply

    drops the last character of a string. This is useful in the case

    of the federated storage handler where I'm building a unknown

    number, list of values and fields to be used in a sql insert

    statement to be run on the remote server, and have a comma after each.

    When the list is complete, I "chop" off the trailing comma

    ex. 

      String stringobj; 

      stringobj.append("VALUES ('foo', 'fi', 'fo',");

      stringobj.chop();

      stringobj.append(")");

    In this case, the value of string was:

    VALUES ('foo', 'fi', 'fo',

    VALUES ('foo', 'fi', 'fo'

    VALUES ('foo', 'fi', 'fo')

  */

  inline void chop()

  {

    Ptr[str_length--]= '\0'; 

  }

  inline void free()

  {

    if (alloced)

    {

      alloced=0;

      Alloced_length=0;

      my_free(Ptr,MYF(0));

      Ptr=0;

      str_length=0;				/* Safety */

    }

  }

  inline bool alloc(uint32 arg_length)

  {

    if (arg_length < Alloced_length)

      return 0;

    return real_alloc(arg_length);

  }

  bool real_alloc(uint32 arg_length);			// Empties old string

  bool realloc(uint32 arg_length);

  inline void shrink(uint32 arg_length)		// Shrink buffer

  {

    if (arg_length < Alloced_length)

    {

      char *new_ptr;

      if (!(new_ptr=(char*) my_realloc(Ptr,arg_length,MYF(0))))

      {

	Alloced_length = 0;

	real_alloc(arg_length);

      }

      else

      {

	Ptr=new_ptr;

	Alloced_length=arg_length;

      }

    }

  }

  bool is_alloced() { return alloced; }

  inline String& operator = (const String &s)

  {

    if (&s != this)

    {

      /*

        It is forbidden to do assignments like 

        some_string = substring_of_that_string

       */

      DBUG_ASSERT(!s.uses_buffer_owned_by(this));

      free();

      Ptr=s.Ptr ; str_length=s.str_length ; Alloced_length=s.Alloced_length;

      alloced=0;

    }

    return *this;

  }

  bool copy();					// Alloc string if not alloced

  bool copy(const String &s);			// Allocate new string

  bool copy(const char *s,uint32 arg_length, CHARSET_INFO *cs);	// Allocate new string

  static bool needs_conversion(uint32 arg_length,

  			       CHARSET_INFO *cs_from, CHARSET_INFO *cs_to,

			       uint32 *offset);

  bool copy_aligned(const char *s, uint32 arg_length, uint32 offset,

		    CHARSET_INFO *cs);

  bool set_or_copy_aligned(const char *s, uint32 arg_length, CHARSET_INFO *cs);

  bool copy(const char*s,uint32 arg_length, CHARSET_INFO *csfrom,

	    CHARSET_INFO *csto, uint *errors);

  bool append(const String &s);

  bool append(const char *s);

  bool append(const char *s,uint32 arg_length);

  bool append(const char *s,uint32 arg_length, CHARSET_INFO *cs);

  bool append(IO_CACHE* file, uint32 arg_length);

  bool append_with_prefill(const char *s, uint32 arg_length, 

			   uint32 full_length, char fill_char);

  int strstr(const String &search,uint32 offset=0); // Returns offset to substring or -1

  int strrstr(const String &search,uint32 offset=0); // Returns offset to substring or -1

  bool replace(uint32 offset,uint32 arg_length,const char *to,uint32 length);

  bool replace(uint32 offset,uint32 arg_length,const String &to);

  inline bool append(char chr)

  {

    if (str_length < Alloced_length)

    {

      Ptr[str_length++]=chr;

    }

    else

    {

      if (realloc(str_length+1))

	return 1;

      Ptr[str_length++]=chr;

    }

    return 0;

  }

  bool fill(uint32 max_length,char fill);

  void strip_sp();

  friend int sortcmp(const String *a,const String *b, CHARSET_INFO *cs);

  friend int stringcmp(const String *a,const String *b);

  friend String *copy_if_not_alloced(String *a,String *b,uint32 arg_length);

  uint32 numchars();

  int charpos(int i,uint32 offset=0);

  int reserve(uint32 space_needed)

  {

    return realloc(str_length + space_needed);

  }

  int reserve(uint32 space_needed, uint32 grow_by);

  /*

    The following append operations do NOT check alloced memory

    q_*** methods writes values of parameters itself

    qs_*** methods writes string representation of value

  */

  void q_append(const char c)

  {

    Ptr[str_length++] = c;

  }

  void q_append(const uint32 n)

  {

    int4store(Ptr + str_length, n);

    str_length += 4;

  }

  void q_append(double d)

  {

    float8store(Ptr + str_length, d);

    str_length += 8;

  }

  void q_append(double *d)

  {

    float8store(Ptr + str_length, *d);

    str_length += 8;

  }

  void q_append(const char *data, uint32 data_len)

  {

    memcpy(Ptr + str_length, data, data_len);

    str_length += data_len;

  }

  void write_at_position(int position, uint32 value)

  {

    int4store(Ptr + position,value);

  }

  void qs_append(const char *str, uint32 len);

  void qs_append(double d);

  void qs_append(double *d);

  inline void qs_append(const char c)

  {

     Ptr[str_length]= c;

     str_length++;

  }

  void qs_append(int i);

  void qs_append(uint i);

  /* Inline (general) functions used by the protocol functions */

  inline char *prep_append(uint32 arg_length, uint32 step_alloc)

  {

    uint32 new_length= arg_length + str_length;

    if (new_length > Alloced_length)

    {

      if (realloc(new_length + step_alloc))

        return 0;

    }

    uint32 old_length= str_length;

    str_length+= arg_length;

    return Ptr+ old_length;			/* Area to use */

  }

  inline bool append(const char *s, uint32 arg_length, uint32 step_alloc)

  {

    uint32 new_length= arg_length + str_length;

    if (new_length > Alloced_length && realloc(new_length + step_alloc))

      return TRUE;

    memcpy(Ptr+str_length, s, arg_length);

    str_length+= arg_length;

    return FALSE;

  }

  void print(String *print);

  /* Swap two string objects. Efficient way to exchange data without memcpy. */

  void swap(String &s);

  inline bool uses_buffer_owned_by(const String *s) const

  {

    return (s->alloced && Ptr >= s->Ptr && Ptr < s->Ptr + s->str_length);

  }

};