txt.c

/*
 * Part of DNS zone file validator `validns`.
 *
 * Copyright 2011-2014 Anton Berezin <tobez@tobez.org>
 * Modified BSD license.
 * (See LICENSE file in the distribution.)
 *
 */
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "common.h"
#include "textparse.h"
#include "mempool.h"
#include "carp.h"
#include "rr.h"

/* XXX Does not accept multiple character-strings */

static struct rr *txt_parse(char *name, long ttl, int type, char *s)
{
	struct rr_txt *rr;
	struct binary_data txt;
	struct rr_txt_segment *first = NULL;
	struct rr_txt_segment *last  = NULL;
	struct rr_txt_segment *cur   = NULL;
	int i;

	i = 0;
	while (*s) {
		freeall_temp();
		txt = extract_text(&s, "text segment");
		if (txt.length < 0)
			return NULL;
		if (txt.length > 255)
			return bitch("TXT segment too long");
		i++;
		cur = getmem(sizeof(*cur));
		cur->txt = txt;
		cur->next = NULL;
		if (!first)
			first = cur;
		if (last)
			last->next = cur;
		last = cur;
	}
	if (i == 0)
		return bitch("empty text record");

   	rr = getmem(sizeof(*rr));
	rr->count = i;
	rr->txt = first;

	return store_record(type, name, ttl, rr);
}

static char* txt_human(struct rr *rrv)
{
	RRCAST(txt);
    char ss[1024];
	char *s = ss;
	int l;
	struct rr_txt_segment *seg = rr->txt;

	while (seg) {
		/* XXX would be nice to escape " with \ in strings */
		l = snprintf(s, 1024-(s-ss), "\"%s\" ", seg->txt.data);
		s += l;
		seg = seg->next;
	}
    return quickstrdup_temp(ss);
}

static struct binary_data txt_wirerdata(struct rr *rrv)
{
	RRCAST(txt);
	struct binary_data r, t;
	struct rr_txt_segment *seg = rr->txt;

	r = bad_binary_data();
	t.length = 0;
	t.data = NULL;
	while (seg) {
		r = compose_binary_data("db", 1, t, seg->txt);
		t = r;
		seg = seg->next;
	}
    return r;
}

struct rr_methods txt_methods = { txt_parse, txt_human, txt_wirerdata, NULL, NULL };