static int add_str(LuaMatchState *ms, char_buffer_st **b, const char *str, size_t len){
char_buffer_st *tmp = *b;
if(tmp->used+len >= tmp->size){
tmp = (char_buffer_st*)realloc(tmp, sizeof(char_buffer_st) + tmp->size + NEW_SIZE(len));
if(!tmp){
ms->error = "not enough memory when reallocating";
return 0;
}
*b = tmp;
}
memcpy(&tmp->buf[tmp->used], str, len);
tmp->used += len;
return 1;
}
char_buffer_st *lua_gsub(const char *src, size_t srcl, const char *p, size_t lp,const char *tr, size_t max_s, const char **error_ptr)
{
int anchor;
size_t n;
LuaMatchState ms;
char_buffer_st *b;
if(max_s == 0) max_s = srcl+1;
anchor = (*p == '^');
n = NEW_SIZE(srcl);
b = (char_buffer_st*)malloc(sizeof(char_buffer_st) + n);
if(!b) return NULL;
b->size = n;
b->used = 0;
n = 0;
if (anchor)
p++, lp--; // skip anchor character
ms.error = 0;
ms.src_init = src;
ms.src_end = src+srcl;
ms.p_end = p + lp;
while (n < max_s)
{
const char *e;
ms.level = 0;
e = match(&ms, src, p);
if(ms.error) goto free_and_null;
if (e) {
n++;
if(!add_value(&ms, &b, src, e, tr)) goto free_and_null;
}
if (e && e>src) // non empty match?
src = e; // skip it
else if (src < ms.src_end){
if(!add_char(&ms, &b, *src++)) goto free_and_null;
}
else break;
if (anchor) break;
}
if(!add_str(&ms, &b, src, ms.src_end-src)) goto free_and_null;
b->buf[b->used] = '\0';
return b;
free_and_null:
if(b) free(b);
if(error_ptr) *error_ptr = ms.error;
return NULL;
}