diff options
Diffstat (limited to 'sql/sql_string.h')
| -rw-r--r-- | sql/sql_string.h | 48 |
1 files changed, 30 insertions, 18 deletions
diff --git a/sql/sql_string.h b/sql/sql_string.h index e595de47f99..dc9122a4fcb 100644 --- a/sql/sql_string.h +++ b/sql/sql_string.h @@ -53,23 +53,24 @@ uint convert_to_printable(char *to, size_t to_len, class String { char *Ptr; - uint32 str_length,Alloced_length; + uint32 str_length,Alloced_length, extra_alloc; bool alloced; CHARSET_INFO *str_charset; public: String() { - Ptr=0; str_length=Alloced_length=0; alloced=0; + Ptr=0; str_length=Alloced_length=extra_alloc=0; alloced=0; str_charset= &my_charset_bin; } String(uint32 length_arg) { - alloced=0; Alloced_length=0; (void) real_alloc(length_arg); + alloced=0; Alloced_length= extra_alloc= 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; + Ptr=(char*) str; str_length= (uint32) strlen(str); + Alloced_length= extra_alloc= 0; alloced=0; str_charset=cs; } /* @@ -79,18 +80,18 @@ public: */ String(const char *str,uint32 len, CHARSET_INFO *cs) { - Ptr=(char*) str; str_length=len; Alloced_length=0; alloced=0; + Ptr=(char*) str; str_length=len; Alloced_length= extra_alloc=0; alloced=0; str_charset=cs; } String(char *str,uint32 len, CHARSET_INFO *cs) { - Ptr=(char*) str; Alloced_length=str_length=len; alloced=0; + Ptr=(char*) str; Alloced_length=str_length=len; extra_alloc= 0; alloced=0; str_charset=cs; } String(const String &str) { Ptr=str.Ptr ; str_length=str.str_length ; - Alloced_length=str.Alloced_length; alloced=0; + Alloced_length=str.Alloced_length; extra_alloc= 0; alloced=0; str_charset=str.str_charset; } static void *operator new(size_t size, MEM_ROOT *mem_root) throw () @@ -106,8 +107,10 @@ public: inline CHARSET_INFO *charset() const { return str_charset; } inline uint32 length() const { return str_length;} inline uint32 alloced_length() const { return Alloced_length;} + inline uint32 extra_allocation() const { return extra_alloc;} inline char& operator [] (uint32 i) const { return Ptr[i]; } inline void length(uint32 len) { str_length=len ; } + inline void extra_allocation(uint32 len) { extra_alloc= 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; } @@ -136,23 +139,21 @@ public: { DBUG_ASSERT(&str != this); free(); - Ptr=(char*) str.ptr()+offset; str_length=arg_length; alloced=0; + Ptr=(char*) str.ptr()+offset; str_length=arg_length; 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; + Ptr=(char*) str; str_length=Alloced_length=arg_length; 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; + Ptr=(char*) str; str_length=arg_length; str_charset=cs; } bool set_ascii(const char *str, uint32 arg_length); @@ -203,11 +204,11 @@ public: if (alloced) { alloced=0; - Alloced_length=0; my_free(Ptr,MYF(0)); - Ptr=0; - str_length=0; /* Safety */ } + Alloced_length= extra_alloc= 0; + Ptr=0; + str_length=0; /* Safety */ } inline bool alloc(uint32 arg_length) { @@ -217,9 +218,21 @@ public: } bool real_alloc(uint32 arg_length); // Empties old string bool realloc(uint32 arg_length); - inline void shrink(uint32 arg_length) // Shrink buffer + bool realloc_with_extra(uint32 arg_length) + { + if (extra_alloc < 4096) + extra_alloc= extra_alloc*2+128; + return realloc(arg_length + extra_alloc); + } + bool realloc_with_extra_if_needed(uint32 arg_length) { if (arg_length < Alloced_length) + return 0; + return realloc_with_extra(arg_length); + } + inline void shrink(uint32 arg_length) // Shrink buffer + { + if (ALIGN_SIZE(arg_length+1) < Alloced_length) { char *new_ptr; if (!(new_ptr=(char*) my_realloc(Ptr,arg_length,MYF(0)))) @@ -246,7 +259,6 @@ public: 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; } @@ -281,7 +293,7 @@ public: } else { - if (realloc(str_length+1)) + if (realloc_with_extra(str_length + 1)) return 1; Ptr[str_length++]=chr; } |