kstring.h

#ifndef KSTRING_H
#define KSTRING_H

#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#ifndef kroundup32
#define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
#endif

#ifndef KSTRING_T
#define KSTRING_T kstring_t
typedef struct __kstring_t {
	size_t l, m;
	char *s;
} kstring_t;
#endif

int ksprintf(kstring_t *s, const char *fmt, ...);
int ksplit_core(char *s, int delimiter, int *_max, int **_offsets);

// calculate the auxiliary array, allocated by calloc()
int *ksBM_prep(const uint8_t *pat, int m);

/* Search pat in str and returned the list of matches. The size of the
 * list is returned as n_matches. _prep is the array returned by
 * ksBM_prep(). If it is a NULL pointer, ksBM_prep() will be called. */
int *ksBM_search(const uint8_t *str, int n, const uint8_t *pat, int m, int *_prep, int *n_matches);

static inline int kputsn(const char *p, int l, kstring_t *s)
{
	if (s->l + l + 1 >= s->m) {
		s->m = s->l + l + 2;
		kroundup32(s->m);
		s->s = (char*)realloc(s->s, s->m);
	}
	strncpy(s->s + s->l, p, l);
	s->l += l;
	s->s[s->l] = 0;
	return l;
}

static inline int kputs(const char *p, kstring_t *s)
{
	return kputsn(p, strlen(p), s);
}

static inline int kputc(int c, kstring_t *s)
{
	if (s->l + 1 >= s->m) {
		s->m = s->l + 2;
		kroundup32(s->m);
		s->s = (char*)realloc(s->s, s->m);
	}
	s->s[s->l++] = c;
	s->s[s->l] = 0;
	return c;
}

static inline int *ksplit(kstring_t *s, int delimiter, int *n)
{
	int max = 0, *offsets = 0;
	*n = ksplit_core(s->s, delimiter, &max, &offsets);
	return offsets;
}

#endif