#ifndef SQL_STRING_INCLUDED
#define SQL_STRING_INCLUDED

/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

 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 */

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

#include "m_ctype.h" /* my_charset_bin */
#include "my_sys.h" /* alloc_root, my_free, my_realloc */
#include "m_string.h" /* TRASH */


/**
 A wrapper class for null-terminated constant strings.
 Constructors make sure that the position of the '0円' terminating byte
 in m_str is always in sync with m_length.

 This class must stay as small as possible as we often 
 pass it and its descendants (such as Name_string) into functions
 using call-by-value evaluation.

 Don't add new members or virual methods into this class!
*/
class Simple_cstring
{
private:
 const char *m_str;
 size_t m_length;
protected:
 /**
 Initialize from a C string whose length is already known.
 */
 void set(const char *str_arg, size_t length_arg)
 {
 // NULL is allowed only with length==0
 DBUG_ASSERT(str_arg || length_arg == 0);
 // For non-NULL, make sure length_arg is in sync with '0円' terminator.
 DBUG_ASSERT(!str_arg || str_arg[length_arg] == '0円');
 m_str= str_arg;
 m_length= length_arg;
 }
public:
 Simple_cstring()
 {
 set(NULL, 0);
 }
 Simple_cstring(const char *str_arg, size_t length_arg)
 {
 set(str_arg, length_arg);
 }
 Simple_cstring(const LEX_STRING arg)
 {
 set(arg.str, arg.length);
 }
 void reset()
 {
 set(NULL, 0);
 }
 /**
 Set to a null-terminated string.
 */
 void set(const char *str)
 {
 set(str, str ? strlen(str) : 0);
 }
 /**
 Return string buffer.
 */
 const char *ptr() const { return m_str; }
 /**
 Check if m_ptr is set.
 */
 bool is_set() const { return m_str != NULL; }
 /**
 Return name length.
 */
 size_t length() const { return m_length; }
 /**
 Compare to another Simple_cstring.
 */
 bool eq_bin(const Simple_cstring other) const
 {
 return m_length == other.m_length &&
 memcmp(m_str, other.m_str, m_length) == 0;
 }
 /**
 Copy to the given buffer
 */
 void strcpy(char *buff) const
 {
 memcpy(buff, m_str, m_length);
 buff[m_length]= '0円';
 }
};


class String;
typedef struct charset_info_st CHARSET_INFO;
typedef struct st_io_cache IO_CACHE;
typedef struct st_mem_root MEM_ROOT;

int sortcmp(const String *a,const String *b, const CHARSET_INFO *cs);
String *copy_if_not_alloced(String *a,String *b,uint32 arg_length);
inline uint32 copy_and_convert(char *to, uint32 to_length,
 const CHARSET_INFO *to_cs,
 const char *from, uint32 from_length,
 const CHARSET_INFO *from_cs, uint *errors)
{
 return my_convert(to, to_length, to_cs, from, from_length, from_cs, errors);
}
uint32 well_formed_copy_nchars(const CHARSET_INFO *to_cs,
 char *to, uint to_length,
 const CHARSET_INFO *from_cs,
 const char *from, uint from_length,
 uint nchars,
 const char **well_formed_error_pos,
 const char **cannot_convert_error_pos,
 const char **from_end_pos);
size_t my_copy_with_hex_escaping(const CHARSET_INFO *cs,
 char *dst, size_t dstlen,
 const char *src, size_t srclen);
uint convert_to_printable(char *to, size_t to_len,
 const char *from, size_t from_len,
 const CHARSET_INFO *from_cs, size_t nbytes= 0);

class String
{
 char *Ptr;
 uint32 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 length_arg)
 { 
 alloced=0; Alloced_length=0; (void) real_alloc(length_arg); 
 str_charset= &my_charset_bin;
 }
 String(const char *str, const 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, const CHARSET_INFO *cs)
 { 
 Ptr=(char*) str; str_length=len; Alloced_length=0; alloced=0;
 str_charset=cs;
 }
 String(char *str,uint32 len, const 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) throw ()
 { return (void*) alloc_root(mem_root, (uint) size); }
 static void operator delete(void *ptr_arg, size_t size)
 {
 (void) ptr_arg;
 (void) size;
 TRASH(ptr_arg, size);
 }
 static void operator delete(void *, MEM_ROOT *)
 { /* never called */ }
 ~String() { free(); }

 inline void set_charset(const CHARSET_INFO *charset_arg)
 { str_charset= charset_arg; }
 inline const 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() const { return (str_length == 0); }
 inline void mark_as_const() { Alloced_length= 0;}
 inline const char *ptr() const { return Ptr; }
 inline char *c_ptr()
 {
 DBUG_ASSERT(!alloced || !Ptr || !Alloced_length || 
 (Alloced_length >= (str_length + 1)));

 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;
 }
 LEX_STRING lex_string() const
 {
 LEX_STRING lex_string = { (char*) ptr(), length() };
 return lex_string;
 }

 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;
 }


 /**
 Points the internal buffer to the supplied one. The old buffer is freed.
 @param str Pointer to the new buffer.
 @param arg_length Length of the new buffer in characters, excluding any 
 null character.
 @param cs Character set to use for interpreting string data.
 @note The new buffer will not be null terminated.
 */
 inline void set(char *str,uint32 arg_length, const 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, const 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, const CHARSET_INFO *cs)
 {
 if (!alloced)
 {
 Ptr=(char*) str; str_length=Alloced_length=arg_length;
 }
 str_charset=cs;
 }
 bool set_int(longlong num, bool unsigned_flag, const CHARSET_INFO *cs);
 bool set(longlong num, const CHARSET_INFO *cs)
 { return set_int(num, false, cs); }
 bool set(ulonglong num, const CHARSET_INFO *cs)
 { return set_int((longlong)num, true, cs); }
 bool set_real(double num,uint decimals, const CHARSET_INFO *cs);

 /*
 PMG 2004年11月12日
 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()
 {
 str_length--;
 Ptr[str_length]= '0円';
 DBUG_ASSERT(strlen(Ptr) == str_length);
 }

 inline void free()
 {
 if (alloced)
 {
 alloced=0;
 Alloced_length=0;
 my_free(Ptr);
 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);

 // Shrink the buffer, but only if it is allocated on the heap.
 inline void shrink(uint32 arg_length)
 {
 if (!is_alloced())
 return;
 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() const { 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;
 str_charset=s.str_charset;
 alloced=0;
 }
 return *this;
 }
 /**
 Takeover the buffer owned by another string.
 "this" becames the owner of the buffer and
 is further responsible to free it.
 The string "s" is detouched from the buffer (cleared).

 @param s - a String object to steal buffer from.
 */
 inline void takeover(String &s)
 {
 DBUG_ASSERT(this != &s);
 // Make sure buffers of the two Strings do not overlap
 DBUG_ASSERT(!s.uses_buffer_owned_by(this));
 free();
 Ptr= s.Ptr;
 str_length= s.str_length;
 Alloced_length= s.Alloced_length;
 alloced= s.alloced;
 str_charset= s.str_charset;
 s.Ptr= NULL;
 s.Alloced_length= 0;
 s.str_length= 0;
 s.alloced= 0;
 }

 bool copy();					// Alloc string if not alloced
 bool copy(const String &s);			// Allocate new string
 // Allocate new string
 bool copy(const char *s,uint32 arg_length, const CHARSET_INFO *cs);
 static bool needs_conversion(uint32 arg_length,
 			 const CHARSET_INFO *cs_from, const CHARSET_INFO *cs_to,
			 uint32 *offset);
 static bool needs_conversion_on_storage(uint32 arg_length,
 const CHARSET_INFO *cs_from,
 const CHARSET_INFO *cs_to);
 bool copy_aligned(const char *s, uint32 arg_length, uint32 offset,
		 const CHARSET_INFO *cs);
 bool set_or_copy_aligned(const char *s, uint32 arg_length,
 const CHARSET_INFO *cs);
 bool copy(const char*s,uint32 arg_length, const CHARSET_INFO *csfrom,
	 const CHARSET_INFO *csto, uint *errors);
 bool append(const String &s);
 bool append(const char *s);
 bool append(LEX_STRING *ls)
 {
 return append(ls->str, (uint32) ls->length);
 }
 bool append(Simple_cstring str)
 {
 return append(str.ptr(), static_cast<uint>(str.length()));
 }
 bool append(const char *s, uint32 arg_length);
 bool append(const char *s, uint32 arg_length, const CHARSET_INFO *cs);
 bool append_ulonglong(ulonglong val);
 bool append(IO_CACHE* file, uint32 arg_length);
 bool append_with_prefill(const char *s, uint32 arg_length, 
			 uint32 full_length, char fill_char);
 bool append_parenthesized(long nr, int radix= 10);
 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, const 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() const;
 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);
 }
 bool is_ascii() const
 {
 if (length() == 0)
 return TRUE;
 if (charset()->mbminlen > 1)
 return FALSE;
 for (const char *c= ptr(), *end= c + length(); c < end; c++)
 {
 if (!my_isascii(*c))
 return FALSE;
 }
 return TRUE;
 }
 /**
 Make a zero-terminated copy of our value,allocated in the specified MEM_ROOT

 @param root MEM_ROOT to allocate the result

 @return allocated string or NULL
 */
 char *dup(MEM_ROOT *root) const
 {
 if (str_length > 0 && Ptr[str_length - 1] == 0)
 return static_cast<char *>(memdup_root(root, Ptr, str_length));

 char *ret= static_cast<char*>(alloc_root(root, str_length + 1));
 if (ret != NULL)
 {
 memcpy(ret, Ptr, str_length);
 ret[str_length]= 0;
 }
 return ret;
 }
};


/**
 String class wrapper with a preallocated buffer of size buff_sz

 This class allows to replace sequences of:
 char buff[12345];
 String str(buff, sizeof(buff));
 str.length(0);
 with a simple equivalent declaration:
 StringBuffer<12345> str;
*/

template<size_t buff_sz>
class StringBuffer : public String
{
 char buff[buff_sz];

public:
 StringBuffer() : String(buff, buff_sz, &my_charset_bin) { length(0); }
 explicit StringBuffer(const CHARSET_INFO *cs) : String(buff, buff_sz, cs)
 {
 length(0);
 }
 StringBuffer(const char *str, size_t length, const CHARSET_INFO *cs)
 : String(buff, buff_sz, cs)
 {
 set(str, length, cs);
 }
};


static inline bool check_if_only_end_space(const CHARSET_INFO *cs, char *str, 
 char *end)
{
 return str+ cs->cset->scan(cs, str, end, MY_SEQ_SPACES) == end;
}

#endif /* SQL_STRING_INCLUDED */