postgis/liblwgeom/stringbuffer.h
Paul Ramsey c23debb38a Convert GeoJSON output to use stringbuffer instead of count-n-fill procedure. Much less code.
Performance for large-amounts-of-small objects is about 10% faster. Performance for larger
objects (natural earth admin for example) is 3%-5% slower.
2022-12-05 15:07:32 -08:00

128 lines
3.8 KiB
C

/**********************************************************************
*
* PostGIS - Spatial Types for PostgreSQL
* http://postgis.net
*
* PostGIS 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.
*
* PostGIS 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 PostGIS. If not, see <http://www.gnu.org/licenses/>.
*
**********************************************************************
*
* Copyright 2002 Thamer Alharbash
* Copyright 2009 Paul Ramsey <pramsey@cleverelephant.ca>
*
**********************************************************************/
#ifndef _STRINGBUFFER_H
#define _STRINGBUFFER_H 1
#include "liblwgeom_internal.h"
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <stdio.h>
#define STRINGBUFFER_STARTSIZE 128
typedef struct
{
size_t capacity;
char *str_end;
char *str_start;
}
stringbuffer_t;
extern stringbuffer_t *stringbuffer_create_with_size(size_t size);
extern stringbuffer_t *stringbuffer_create(void);
extern void stringbuffer_init(stringbuffer_t *s);
extern void stringbuffer_init_varlena(stringbuffer_t *s);
extern void stringbuffer_release(stringbuffer_t *s);
extern void stringbuffer_destroy(stringbuffer_t *sb);
extern void stringbuffer_clear(stringbuffer_t *sb);
void stringbuffer_set(stringbuffer_t *sb, const char *s);
void stringbuffer_copy(stringbuffer_t *sb, stringbuffer_t *src);
extern int stringbuffer_aprintf(stringbuffer_t *sb, const char *fmt, ...);
extern const char *stringbuffer_getstring(stringbuffer_t *sb);
extern char *stringbuffer_getstringcopy(stringbuffer_t *sb);
extern lwvarlena_t *stringbuffer_getvarlenacopy(stringbuffer_t *s);
extern lwvarlena_t * stringbuffer_getvarlena(stringbuffer_t *s);
extern int stringbuffer_getlength(stringbuffer_t *sb);
extern char stringbuffer_lastchar(stringbuffer_t *s);
extern int stringbuffer_trim_trailing_white(stringbuffer_t *s);
extern int stringbuffer_trim_trailing_zeroes(stringbuffer_t *s);
/**
* If necessary, expand the stringbuffer_t internal buffer to accommodate the
* specified additional size.
*/
static inline void
stringbuffer_makeroom(stringbuffer_t *s, size_t size_to_add)
{
size_t current_size = (s->str_end - s->str_start);
size_t capacity = s->capacity;
size_t required_size = current_size + size_to_add;
while (capacity < required_size)
capacity *= 2;
if (capacity > s->capacity)
{
s->str_start = lwrealloc(s->str_start, capacity);
s->capacity = capacity;
s->str_end = s->str_start + current_size;
}
}
/**
* Append the specified string to the stringbuffer_t using known length
*/
inline static void
stringbuffer_append_len(stringbuffer_t *s, const char *a, size_t alen)
{
int alen0 = alen + 1; /* Length including null terminator */
stringbuffer_makeroom(s, alen0);
memcpy(s->str_end, a, alen0);
s->str_end += alen;
}
/**
* Append the specified string to the stringbuffer_t.
*/
inline static void
stringbuffer_append(stringbuffer_t *s, const char *a)
{
int alen = strlen(a); /* Length of string to append */
stringbuffer_append_len(s, a, alen);
}
inline static void
stringbuffer_append_double(stringbuffer_t *s, double d, int precision)
{
stringbuffer_makeroom(s, OUT_MAX_BYTES_DOUBLE);
s->str_end += lwprint_double(d, precision, s->str_end);
}
inline static void
stringbuffer_append_char(stringbuffer_t *s, char c)
{
stringbuffer_makeroom(s, 1);
*(s->str_end) = c;
s->str_end++;
}
#endif /* _STRINGBUFFER_H */