undefined reference to `lzo1z_decompress'

[hrdksanghavi]

Hello,

I am trying to decompress a data buffer through LZO decompression algorithm.
But it throws an error while building the code.

"/usr/bin/gmake" -f nbproject/Makefile-Debug.mk QMAKE= SUBPROJECTS= .build-conf
gmake[1]: Entering directory `/root/NetBeansProjects/Projects/CFNORawServer'
"/usr/bin/gmake" -f nbproject/Makefile-Debug.mk dist/Debug/GNU-Linux-x86/cfnorawserver
gmake[2]: Entering directory `/root/NetBeansProjects/Projects/CFNORawServer'
gmake[2]: Warning: File `Include/lzoconf.h' has modification time 3.7e+04 s in the future
mkdir -p build/Debug/GNU-Linux-x86
rm -f build/Debug/GNU-Linux-x86/main.o.d
gcc -c -g -MMD -MP -MF build/Debug/GNU-Linux-x86/main.o.d -o build/Debug/GNU-Linux-x86/main.o main.c
mkdir -p dist/Debug/GNU-Linux-x86
gcc -o dist/Debug/GNU-Linux-x86/cfnorawserver build/Debug/GNU-Linux-x86/main.o
build/Debug/GNU-Linux-x86/main.o: In function `main':
/root/NetBeansProjects/Projects/CFNORawServer/main.c:127: undefined reference to `lzo1z_decompress'
collect2: ld returned 1 exit status
gmake[2]: *** [dist/Debug/GNU-Linux-x86/cfnorawserver] Error 1
gmake[2]: Leaving directory `/root/NetBeansProjects/Projects/CFNORawServer'
gmake[1]: *** [.build-conf] Error 2
gmake[1]: Leaving directory `/root/NetBeansProjects/Projects/CFNORawServer'
gmake: *** [.build-impl] Error 2
BUILD FAILED (exit value 2, total time: 331ms)

MY CODE IS :

memset(recv_str,0,sizeof(recv_str));
from_len = sizeof(from_addr);
memset(&from_addr,0,from_len);
if((recv_len = recvfrom(sock, recv_str, 1024, 0, (struct sockaddr*)&mc_addr, &from_len)) < 0)
{
perror("recvfrom() failed");
exit(1);
}
short compLen=0;
short NOP=0;
memcpy(&compLen,recv_str+4,2);
compLen = ntohs(compLen);
if(compLen > 0)
{
memcpy(&NOP,recv_str+2,2);
NOP=ntohs(NOP);
int i=0;


for(i=0;i<NOP;i++)
{
unsigned char src[compLen];
memcpy(&src,recv_str+6,compLen);
short src_len = compLen;
unsigned int dst_len = 1024;
unsigned char dst[1024];
int rCode;
unsigned int eCode=0;
rCode = lzo1z_decompress((lzo_bytep) src ,(lzo_uint)src_len ,(lzo_bytep) dst ,lzo_uintp)&dst_len ,0);

}

}

[Alex F]

gcc -o dist/Debug/GNU-Linux-x86/cfnorawserver build/Debug/GNU-Linux-x86/main.o

Where is lzo1z_decompress function defined? You need to add the library with this function to the linking command line, something like:

gcc -o dist/Debug/GNU-Linux-x86/cfnorawserver build/Debug/GNU-Linux-x86/main.o -llzo

(I don't know exact library name, just guess)

[hrdksanghavi]

Hello,

lzo1z_decompress is defined in the header file lzo1z.h

My complete code is:

/*
 * File:   main.c
 * Author: root
 *
 * Created on May 17, 2011, 1:51 PM
 */

#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "Include/lzo1z.h"

#define MAX_LEN 1024;

int main(int argc, char **argv)
{
    
    int sock;
    int flag_on = 1;
    struct sockaddr_in mc_addr;
    unsigned char recv_str[1024];
    int  recv_len;
    struct ip_mreq mc_req;
    char* mc_addr_str;
    unsigned short mc_port;
    struct sockaddr_in from_addr;
    unsigned int from_len;
    mc_addr_str = "233.1.1.11";
    mc_port     = 34330;
      
    if ((sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
    {
        perror("socket() failed");
        exit(1);
    }

    if ((setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &flag_on, sizeof(flag_on))) < 0)
    {
        perror("setsockopt() failed");
        exit(1);
    }
    
    memset(&mc_addr,0,sizeof(mc_addr));
    mc_addr.sin_family = AF_INET;
    mc_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    mc_addr.sin_port = htons(mc_port);
    
    if((bind(sock,(struct sockaddr *) &mc_addr,sizeof(mc_addr))) < 0)
    {
        perror("bind() failed");
        exit(1);
    }
    
    mc_req.imr_multiaddr.s_addr = inet_addr(mc_addr_str);
    mc_req.imr_interface.s_addr = htonl(INADDR_ANY);
    
    if((setsockopt(sock,IPPROTO_IP,IP_ADD_MEMBERSHIP,(void*) &mc_req,sizeof(mc_req))) < 0)
    {
        perror("setsockopt() failed");
        exit(1);
    }
    
    
    for(;;)
    {
        memset(recv_str,0,sizeof(recv_str));
        from_len = sizeof(from_addr);
        memset(&from_addr,0,from_len);
        
       if((recv_len = recvfrom(sock, recv_str,1024,0,(struct sockaddr*)&mc_addr, &from_len))<0)                
        {
            perror("recvfrom() failed");
            exit(1);
        }
        short compLen=0;
        short NOP=0;
        memcpy(&compLen,recv_str+4,2);
        compLen = ntohs(compLen);
        if(compLen > 0)
        {
            memcpy(&NOP,recv_str+2,2);
            NOP=ntohs(NOP);
            int i=0;
           
            
            for(i=0;i<NOP;i++)
            {
                unsigned char src[compLen];
                memcpy(&src,recv_str+6,compLen);
                short src_len = compLen;
                unsigned int dst_len = 1024;
                unsigned char dst[1024];
                int rCode;
                unsigned int eCode=0;
                               
                
                rCode = lzo1z_decompress((lzo_bytep) src,(lzo_uint)src_len,(lzo_bytep) dst,(lzo_uintp)&dst_len,0);
                
               
            }
        }
    }
    
    if((setsockopt(sock, IPPROTO_IP, IP_DROP_MEMBERSHIP,(void*)&mc_req, sizeof(mc_req))) < 0)
    {
        perror("setsocketopt() failed");
        exit(1);
        
    }
    close(sock);
    return 0;
}

Hardik.

[hrdksanghavi]

My header file lzo1z.h contains following code:

/* lzo1z.h -- public interface of the LZO1Z compression algorithm

   This file is part of the LZO real-time data compression library.
*/


#ifndef __LZO1Z_H_INCLUDED
#define __LZO1Z_H_INCLUDED

#ifndef __LZOCONF_H_INCLUDED
#include "lzoconf.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif


/***********************************************************************
//
************************************************************************/

/* Memory required for the wrkmem parameter.
 * When the required size is 0, you can also pass a NULL pointer.
 */

#define LZO1Z_MEM_COMPRESS      ((lzo_uint32) (16384L * lzo_sizeof_dict_t))
#define LZO1Z_MEM_DECOMPRESS    (0)
#define LZO1Z_MEM_OPTIMIZE      (0)


/* decompression */
LZO_EXTERN(int)
lzo1z_decompress        ( const lzo_bytep src, lzo_uint  src_len,
                                lzo_bytep dst, lzo_uintp dst_len,
                                lzo_voidp wrkmem /* NOT USED */ );

/* safe decompression with overrun testing */
LZO_EXTERN(int)
lzo1z_decompress_safe   ( const lzo_bytep src, lzo_uint  src_len,
                                lzo_bytep dst, lzo_uintp dst_len,
                                lzo_voidp wrkmem /* NOT USED */ );


/***********************************************************************
//
************************************************************************/

#if 0
/* not yet implemented */
LZO_EXTERN(int)
lzo1z_1_compress        ( const lzo_bytep src, lzo_uint  src_len,
                                lzo_bytep dst, lzo_uintp dst_len,
                                lzo_voidp wrkmem );
#endif


/***********************************************************************
// better compression ratio at the cost of more memory and time
************************************************************************/

#define LZO1Z_999_MEM_COMPRESS  ((lzo_uint32) (14 * 16384L * sizeof(short)))

LZO_EXTERN(int)
lzo1z_999_compress      ( const lzo_bytep src, lzo_uint  src_len,
                                lzo_bytep dst, lzo_uintp dst_len,
                                lzo_voidp wrkmem );


/***********************************************************************
//
************************************************************************/

LZO_EXTERN(int)
lzo1z_999_compress_dict     ( const lzo_bytep in , lzo_uint  in_len,
                                    lzo_bytep out, lzo_uintp out_len,
                                    lzo_voidp wrkmem,
                              const lzo_bytep dict, lzo_uint dict_len );

LZO_EXTERN(int)
lzo1z_999_compress_level    ( const lzo_bytep in , lzo_uint  in_len,
                                    lzo_bytep out, lzo_uintp out_len,
                                    lzo_voidp wrkmem,
                              const lzo_bytep dict, lzo_uint dict_len,
                                    lzo_callback_p cb,
                                    int compression_level );

LZO_EXTERN(int)
lzo1z_decompress_dict_safe ( const lzo_bytep in,  lzo_uint  in_len,
                                   lzo_bytep out, lzo_uintp out_len,
                                   lzo_voidp wrkmem /* NOT USED */,
                             const lzo_bytep dict, lzo_uint dict_len );


/***********************************************************************
// optimize a compressed data block
************************************************************************/

#if 0
/* not yet implemented */
LZO_EXTERN(int)
lzo1z_optimize          (       lzo_bytep in , lzo_uint  in_len,
                                lzo_bytep out, lzo_uintp out_len,
                                lzo_voidp wrkmem /* NOT USED */ );
#endif



#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* already included */


/* vim:set ts=4 et: */

Hardik.

[Alex F]

This is only function forward declaration, without implementation. You need function implementation. If function is implemented in some c/cpp file, add this file to the project. If function is implemented in some library, add this library to the linking command line.

[hrdksanghavi]

Thanks

Hardik.