/* ----------------------------------------------------------------------
 * SFTP packet construction functions.
 */
static void sftp_pkt_ensure(struct sftp_packet *pkt, int length)
{
    if (pkt->maxlen < length) {
	pkt->maxlen = length + 256;
	pkt->data = srealloc(pkt->data, pkt->maxlen);
    }
}
static void sftp_pkt_adddata(struct sftp_packet *pkt, void *data, int len)
{
    pkt->length += len;
    sftp_pkt_ensure(pkt, pkt->length);
    memcpy(pkt->data + pkt->length - len, data, len);
}
static void sftp_pkt_addbyte(struct sftp_packet *pkt, unsigned char byte)
{
    sftp_pkt_adddata(pkt, &byte, 1);
}
static struct sftp_packet *sftp_pkt_init(int pkt_type)
{
    struct sftp_packet *pkt;
    pkt = smalloc(sizeof(struct sftp_packet));
    pkt->data = NULL;
    pkt->savedpos = -1;
    pkt->length = 0;
    pkt->maxlen = 0;
    sftp_pkt_addbyte(pkt, (unsigned char) pkt_type);
    return pkt;
}

{
    struct sftp_packet *pkt;
    char x[4];

    if (!sftp_recvdata(x, 4))
	return NULL;

    pkt = smalloc(sizeof(struct sftp_packet));
    pkt->savedpos = 0;
    pkt->length = pkt->maxlen = GET_32BIT(x);
    pkt->data = smalloc(pkt->length);

    if (!sftp_recvdata(pkt->data, pkt->length)) {
	sftp_pkt_free(pkt);
	return NULL;
    }

    pkt->type = sftp_pkt_getbyte(pkt);

    return pkt;
}

/* ----------------------------------------------------------------------
 * String handling routines.
 */

static char *mkstr(char *s, int len)
{
    char *p = smalloc(len + 1);
    memcpy(p, s, len);
    p[len] = '\0';
    return p;
}

/* ----------------------------------------------------------------------
 * SFTP primitives.

	sftp_pkt_getstring(pktin, &hstring, &len);
	if (!hstring) {
	    fxp_internal_error("OPEN returned malformed FXP_HANDLE\n");
            sftp_pkt_free(pktin);
	    return NULL;
	}
	handle = smalloc(sizeof(struct fxp_handle));
	handle->hstring = mkstr(hstring, len);
	handle->hlen = len;
	sftp_pkt_free(pktin);
	return handle;
    } else {
	fxp_got_status(pktin);
        sftp_pkt_free(pktin);

	sftp_pkt_getstring(pktin, &hstring, &len);
	if (!hstring) {
	    fxp_internal_error("OPENDIR returned malformed FXP_HANDLE\n");
            sftp_pkt_free(pktin);
	    return NULL;
	}
	handle = smalloc(sizeof(struct fxp_handle));
	handle->hstring = mkstr(hstring, len);
	handle->hlen = len;
	sftp_pkt_free(pktin);
	return handle;
    } else {
	fxp_got_status(pktin);
        sftp_pkt_free(pktin);

	fxp_internal_error("request ID mismatch\n");
        sftp_pkt_free(pktin);
	return NULL;
    }
    if (pktin->type == SSH_FXP_NAME) {
	struct fxp_names *ret;
	int i;
	ret = smalloc(sizeof(struct fxp_names));
	ret->nnames = sftp_pkt_getuint32(pktin);
	ret->names = smalloc(ret->nnames * sizeof(struct fxp_name));
	for (i = 0; i < ret->nnames; i++) {
	    char *str;
	    int len;
	    sftp_pkt_getstring(pktin, &str, &len);
	    ret->names[i].filename = mkstr(str, len);
	    sftp_pkt_getstring(pktin, &str, &len);
	    ret->names[i].longname = mkstr(str, len);

/*
 * Duplicate an fxp_name structure.
 */
struct fxp_name *fxp_dup_name(struct fxp_name *name)
{
    struct fxp_name *ret;
    ret = smalloc(sizeof(struct fxp_name));
    ret->filename = dupstr(name->filename);
    ret->longname = dupstr(name->longname);
    ret->attrs = name->attrs;	       /* structure copy */
    return ret;
}

/*