/*
$Id: pa_string.h,v 1.14 2001/01/29 22:34:57 paf Exp $
*/
/*
String Chunk0
====== ========
head--------->[ptr, size]
append_here-------->[ptr, size]
link_row ........
. .
. [ptr, size]
...........>[link to the next chunk]
*/
#ifndef PA_STRING_H
#define PA_STRING_H
#ifdef HAVE_CONFIG_H
#include "pa_config.h"
#endif
#include <stddef.h>
#include "pa_types.h"
class Pool;
#ifndef NO_STRING_ORIGIN
# define STRING_APPEND_PARAMS const char *src, char *file, uint line
# define APPEND(src, file, line) real_append(src, file, line)
#else
# define STRING_APPEND_PARAMS const char *src
# define APPEND(src, file, line) real_append(src)
#endif
class String {
public:
enum {
CR_PREALLOCATED_COUNT=5,
CR_GROW_PERCENT=60
};
public:
void *operator new(size_t size, Pool& apool);
String(Pool& apool);
String(const String& src);
size_t size() const { return fsize; }
int used_rows() const { return fused_rows; }
char *cstr() const;
String& real_append(STRING_APPEND_PARAMS);
bool operator == (const String& src) const;
uint hash_code() const;
const Origin& origin() const { return head.rows[0].item.origin; }
protected:
// the pool I'm allocated on
Pool& pool;
private:
struct Chunk {
// the number of rows in chunk
int count;
union Row {
// chunk item
struct {
const char *ptr; // pointer to the start of string fragment
size_t size; // length of the fragment
Origin origin; // origin of this fragment
} item;
Chunk *link; // link to the next chunk in chain
} rows[CR_PREALLOCATED_COUNT];
// next rows are here
Chunk *preallocated_link;
}
head; // the head chunk of the chunk chain
// next append would write to this record
Chunk::Row *append_here;
// the address of place where lies address
// of the link to the next chunk to allocate
Chunk::Row *link_row;
private:
// last chank allocated count
int curr_chunk_rows;
// string size
size_t fsize;
// used rows in all chunks
int fused_rows;
private:
bool chunk_is_full() {
return append_here == link_row;
}
void expand();
private: //disabled
String& operator = (const String&) { return *this; }
};
#endif
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