#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

typedef struct {
	uint64_t tab[4];
	int sep, finished;
	const char *p; // end of the current token
} ks_tokaux_t;

#ifdef __cplusplus
extern "C" {
#endif

	int ksprintf(kstring_t *s, const char *fmt, ...);
	int ksplit_core(char *s, int delimiter, int *_max, int **_offsets);
	char *kstrstr(const char *str, const char *pat, int **_prep);
	char *kstrnstr(const char *str, const char *pat, int n, int **_prep);
	void *kmemmem(const void *_str, int n, const void *_pat, int m, int **_prep);

	/* kstrtok() is similar to strtok_r() except that str is not
	 * modified and both str and sep can be NULL. For efficiency, it is
	 * actually recommended to set both to NULL in the subsequent calls
	 * if sep is not changed. */
	char *kstrtok(const char *str, const char *sep, ks_tokaux_t *aux);

#ifdef __cplusplus
}
#endif
	
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);
	}
	memcpy(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 kputw(int c, kstring_t *s)
{
	char buf[16];
	int l, x;
	if (c == 0) return kputc('0', s);
	for (l = 0, x = c < 0? -c : c; x > 0; x /= 10) buf[l++] = x%10 + '0';
	if (c < 0) buf[l++] = '-';
	if (s->l + l + 1 >= s->m) {
		s->m = s->l + l + 2;
		kroundup32(s->m);
		s->s = (char*)realloc(s->s, s->m);
	}
	for (x = l - 1; x >= 0; --x) s->s[s->l++] = buf[x];
	s->s[s->l] = 0;
	return 0;
}

static inline int kputuw(unsigned c, kstring_t *s)
{
	char buf[16];
	int l, i;
	unsigned x;
	if (c == 0) return kputc('0', s);
	for (l = 0, x = c; x > 0; x /= 10) buf[l++] = x%10 + '0';
	if (s->l + l + 1 >= s->m) {
		s->m = s->l + l + 2;
		kroundup32(s->m);
		s->s = (char*)realloc(s->s, s->m);
	}
	for (i = l - 1; i >= 0; --i) s->s[s->l++] = buf[i];
	s->s[s->l] = 0;
	return 0;
}

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