#include <stdarg.h>

#include "util/strb.h"

strb *strb_alloc(size_t i) {

strb *res = malloc(sizeof(strb));

if (res == NULL) return NULL;

res->s = malloc(i);

if (res->s == NULL) { free(res); return NULL; }

res->a = i;

res->l = 0;

return res;

}

void strb_free(strb *sb) {

free(sb->s);

free(sb);

}

int strb_grow(strb *sb, size_t n) {

char *s;

if (strb_error(sb)) return -1;

if (sb->a == 0 && n < 1024) n = 1024;

if (sb->a > n) n = sb->a;

/* overflow */

if (SIZE_MAX - sb->a < n) { strb_seterror(sb); return -1; }

s = realloc(sb->s, sb->a + n);

if (s == NULL) {

strb_seterror(sb);

return -1;

}

sb->s = s;

sb->a += n;

return 0;

}

void strb_appendf(strb *sb, const char *f, ...) {

va_list ap;

int s;

va_start(ap, f);

#ifdef _MSC_VER

s = _vscprintf(f, ap);

#else

s = vsnprintf(NULL, 0, f, ap);

#endif

va_end(ap);

if (s < 0) { strb_seterror(sb); return; }

s += 1;

if (strb_ensure(sb, s)) return;

va_start(ap, f);

s = vsnprintf(sb->s+sb->l, s, f, ap);

va_end(ap);

sb->l += s;

}