#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>

#include <arpa/inet.h>
#include <netdb.h>
extern int h_errno;

#include <nss.h>

#define ALIGN(idx) { \
  if (idx % sizeof(void*)) \
    idx += (sizeof(void*) - idx % sizeof(void*)); /* Align on 32 bit boundary */ \
} 


enum nss_status _nss_vdn_gethostbyname2_r(
    const char *name,
    int af,
    struct hostent * result,
    char *buffer,
    size_t buflen,
    int *errnop,
    int *h_errnop)
{
    //fprintf(stderr, "vdn_gethostbyname2_r : %s\n", name);

	FILE *fp;
    char line[80];
	int s;

	size_t idx=0;

	if(af != AF_INET) {
		*errnop = EAFNOSUPPORT;
        *h_errnop = HOST_NOT_FOUND;
        return NSS_STATUS_UNAVAIL;
	}

	char cmd[200]="/etc/vdn/allocators/resolv";

	if (access(cmd, F_OK) != 0) 
		strcpy(cmd, "/home/davalan/vdn-bullseye/allocators/resolv");

	if (access(cmd, F_OK) != 0) {
		perror("access");
		*errnop = EAFNOSUPPORT;
        *h_errnop = HOST_NOT_FOUND;
        return NSS_STATUS_UNAVAIL;
	}

	strcat(cmd, " ");
	strcat(cmd, name);
	if((fp = popen(cmd , "r")) == NULL) {
		perror("open");
		exit(1);
	}

	if(fgets(line, sizeof line, fp) == NULL) {
		*errnop = EAFNOSUPPORT;
        *h_errnop = HOST_NOT_FOUND;
        return NSS_STATUS_UNAVAIL;
	}

	line[strlen(line)-1]=0;

	//fprintf(stderr,"line:%s\n", line);

	pclose(fp);

	//char *bufStart=buffer;

	strcpy(buffer+idx, name);
	result->h_name=buffer;

	idx+=strlen(name)+1;
	ALIGN(idx);

	result->h_addrtype=AF_INET;
	result->h_length=4;

	//fprintf(stderr, "name ok\n");

	s = inet_pton(AF_INET, line, buffer+idx);
    if (s <= 0) {
        if (s == 0) {
			*errnop = EAFNOSUPPORT;
			*h_errnop = HOST_NOT_FOUND;
			return NSS_STATUS_UNAVAIL;
        }
        else {
            perror("inet_pton");
            exit(1);
        }
    }

	result->h_addr_list=(char **)buffer+idx;

	result->h_addr_list[0]=buffer+idx;
	result->h_addr_list[1]=NULL;

	idx+=2*sizeof(char *);

	result->h_aliases=(char **)buffer+idx;

	result->h_aliases[0]=NULL;

	*errnop = 0;
    *h_errnop = 0;

    return NSS_STATUS_SUCCESS;
}