~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008 Sun Microsystems

 *

 *  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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#ifndef DRIZZLED_SQL_STRING_H

#define DRIZZLED_SQL_STRING_H

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

#ifndef NOT_FIXED_DEC

#define NOT_FIXED_DEC			(uint8_t)31

#endif

#include <drizzled/common.h>

#include <mysys/iocache.h>

#include <stdlib.h>

#include <string.h>

class String;

#if defined(__cplusplus)

extern "C" {

#endif

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

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

  String *copy_if_not_alloced(String *a,String *b,uint32_t arg_length);

  uint32_t well_formed_copy_nchars(const CHARSET_INFO * const to_cs,

                                   char *to, uint32_t to_length,

                                   const CHARSET_INFO * const from_cs,

                                   const char *from, uint32_t from_length,

                                   uint32_t nchars,

                                   const char **well_formed_error_pos,

                                   const char **cannot_convert_error_pos,

                                   const char **from_end_pos);

#if defined(__cplusplus)

}

#endif

class String

{

  char *Ptr;

  uint32_t str_length,Alloced_length;

  bool alloced;

  const CHARSET_INFO *str_charset;

public:

  String()

  {

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

    str_charset= &my_charset_bin;

  }

  String(uint32_t length_arg)

  {

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

    str_charset= &my_charset_bin;

  }

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

  {

    Ptr=(char*) str; str_length=(uint32_t) strlen(str); Alloced_length=0; alloced=0;

    str_charset=cs;

  }

  String(const char *str,uint32_t len, const CHARSET_INFO * const cs)

  {

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

    str_charset=cs;

  }

  String(char *str,uint32_t len, const CHARSET_INFO * const 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, (uint32_t) size); } 

  static void operator delete(void *, size_t)

  { TRASH(ptr_arg, size); }

  static void operator delete(void *, MEM_ROOT *)

  { /* never called */ }

  ~String();

  inline void set_charset(const CHARSET_INFO * const charset_arg)

  { str_charset= charset_arg; }

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

  inline uint32_t length() const { return str_length;}

  inline uint32_t alloced_length() const { return Alloced_length;}

  inline char& operator [] (uint32_t i) const { return Ptr[i]; }

  inline void length(uint32_t len) { str_length=len ; }

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

  inline void mark_as_const() { Alloced_length= 0;}

  inline char *ptr() { return Ptr; }

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

  inline char *c_ptr()

  {

    if (str_length == Alloced_length)

      (void) realloc(str_length);

    else

      Ptr[str_length]= 0;

    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 append_identifier(const char *name, uint32_t length);

  void set(String &str,uint32_t offset,uint32_t arg_length)

  {

    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_t arg_length, const CHARSET_INFO * const cs)

  {

    free();

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

    str_charset=cs;

  }

  inline void set(const char *str,uint32_t arg_length, const CHARSET_INFO * const cs)

  {

    free();

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

    str_charset=cs;

  }

  bool set_ascii(const char *str, uint32_t arg_length);

  inline void set_quick(char *str,uint32_t arg_length, const CHARSET_INFO * const cs)

  {

    if (!alloced)

    {

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

    }

    str_charset=cs;

  }

  bool set_int(int64_t num, bool unsigned_flag, const CHARSET_INFO * const cs);

  bool set(int64_t num, const CHARSET_INFO * const cs)

  { return set_int(num, false, cs); }

  bool set(uint64_t num, const CHARSET_INFO * const cs)

  { return set_int((int64_t)num, true, cs); }

  bool set_real(double num,uint32_t decimals, const CHARSET_INFO * const 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;

      ::free(Ptr);

      Ptr=0;

      str_length=0;				/* Safety */

    }

  }

  inline bool alloc(uint32_t arg_length)

  {

    if (arg_length < Alloced_length)

      return 0;

    return real_alloc(arg_length);

  }

  bool real_alloc(uint32_t arg_length);			// Empties old string

  bool realloc(uint32_t arg_length);

  inline void shrink(uint32_t arg_length)		// Shrink buffer

  {

    if (arg_length < Alloced_length)

    {

      char *new_ptr;

      if (!(new_ptr=(char*) ::realloc(Ptr,arg_length)))

      {

	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

       */

      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_t arg_length, const CHARSET_INFO * const cs);	// Allocate new string

  static bool needs_conversion(uint32_t arg_length,

  			       const CHARSET_INFO * const cs_from, const CHARSET_INFO * const cs_to,

			       uint32_t *offset);

  bool set_or_copy_aligned(const char *s, uint32_t arg_length, const CHARSET_INFO * const cs);

  bool copy(const char*s,uint32_t arg_length, const CHARSET_INFO * const csfrom,

	    const CHARSET_INFO * const csto, uint32_t *errors);

  bool append(const String &s);

  bool append(const char *s);

  bool append(const char *s,uint32_t arg_length);

  bool append(const char *s,uint32_t arg_length, const CHARSET_INFO * const cs);

  bool append_with_prefill(const char *s, uint32_t arg_length,

			   uint32_t full_length, char fill_char);

  int strstr(const String &search,uint32_t offset=0); // Returns offset to substring or -1

  int strrstr(const String &search,uint32_t offset=0); // Returns offset to substring or -1

  bool replace(uint32_t offset,uint32_t arg_length,const char *to,uint32_t length);

  bool replace(uint32_t offset,uint32_t 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;

  }

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

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

  friend String *copy_if_not_alloced(String *a,String *b,uint32_t arg_length);

  uint32_t numchars();

  int charpos(int i,uint32_t offset=0);

  int reserve(uint32_t space_needed)

  {

    return realloc(str_length + space_needed);

  }

  int reserve(uint32_t space_needed, uint32_t 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_t 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_t data_len)

  {

    memcpy(Ptr + str_length, data, data_len);

    str_length += data_len;

  }

  void write_at_position(int position, uint32_t value)

  {

    int4store(Ptr + position,value);

  }

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

  inline char *prep_append(uint32_t arg_length, uint32_t step_alloc)

  {

    uint32_t new_length= arg_length + str_length;

    if (new_length > Alloced_length)

    {

      if (realloc(new_length + step_alloc))

        return 0;

    }

    uint32_t old_length= str_length;

    str_length+= arg_length;

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

  }

  inline bool append(const char *s, uint32_t arg_length, uint32_t step_alloc)

  {

    uint32_t 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);

  }

};

static inline bool check_if_only_end_space(const CHARSET_INFO * const cs, char *str,

                                           char *end)

{

  return str+ cs->cset->scan(cs, str, end, MY_SEQ_SPACES) == end;

}

extern "C++" {

bool operator==(const String &s1, const String &s2);

bool operator!=(const String &s1, const String &s2);

}

#endif /* DRIZZLED_SQL_STRING_H */