sql_string.h
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:10k
- /* 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; 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 */
- /* 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,size_t size)
- {}
- static void operator delete(void *ptr_arg, MEM_ROOT *mem_root)
- {}
- ~String() { free(); }
- inline void set_charset(CHARSET_INFO *charset) { str_charset= charset; }
- 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 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);
- 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;
- }
- }
- }
- inline void shrink_to_length()
- {
- Alloced_length= str_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();
- inline void caseup() { my_caseup(str_charset,Ptr,str_length); }
- inline void casedn() { my_casedn(str_charset,Ptr,str_length); }
- 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++;
- }
- /* 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);
- }
- };