int mod2sparse_write
( FILE *f,
mod2sparse *m
)
{
mod2entry *e;
int i;
intio_write(f,m->n_rows);
if (ferror(f)) return 0;
intio_write(f,m->n_cols);
if (ferror(f)) return 0;
for (i = 0; i<mod2sparse_rows(m); i++)
{
e = mod2sparse_first_in_row(m,i);
if (!mod2sparse_at_end(e))
{
intio_write (f, -(i+1));
if (ferror(f)) return 0;
while (!mod2sparse_at_end(e))
{
intio_write (f, mod2sparse_col(e)+1);
if (ferror(f)) return 0;
e = mod2sparse_next_in_row(e);
}
}
}
intio_write(f,0);
if (ferror(f)) return 0;
return 1;
}
int main
( int argc,
char **argv
)
{
mod2dense *D,*Z,*G;
mod2sparse *T;
int *a_col,*a_row;
int *cols2;
char *pchk_file;
char fn[128];
char *code;
FILE *fp;
int i,j,n;
int a,b,c;
int codeLen,checkLen;
pchk_file = argv[3];
sscanf(argv[1],"%ld",&codeLen);
sscanf(argv[2],"%ld",&checkLen);
sprintf(fn,"data/code%dX%d.bin",codeLen,checkLen);
D = mod2dense_allocate( checkLen, codeLen );
code=malloc(codeLen*checkLen);
printf(" read from %s\n",fn);
fp=fopen(fn,"rb");
if( fp==NULL )
{
printf("open file error\n");
return -1;
}
fread(code,codeLen*checkLen,1,fp);
fclose(fp);
mod2dense_clear( D );
for( i=0;i<checkLen;i++ )
for( j=0;j<codeLen;j++ )
{
if( code[i*codeLen+j] )
mod2dense_set( D, i, j, 1 );
}
T = mod2sparse_allocate( checkLen, codeLen );
mod2dense_to_sparse( D , T );
fp = open_file_std(pchk_file,"wb");
if (fp==NULL)
{ fprintf(stderr,"Can't create parity check file: %s\n",pchk_file);
exit(1);
}
intio_write(fp,('P'<<8)+0x80);
if (ferror(fp) || !mod2sparse_write(fp,T) || fclose(fp)!=0)
{ fprintf(stderr,"Error writing to parity check file %s\n",pchk_file);
exit(1);
}
free(code);
return 0;
}
int main
( int argc,
char **argv
)
{
make_method method;
char *file, **meth;
int seed, no4cycle;
distrib *d;
char junk;
FILE *f;
/* Look at initial arguments. */
if (!(file = argv[1])
|| !argv[2] || sscanf(argv[2],"%d%c",&M,&junk)!=1 || M<=0
|| !argv[3] || sscanf(argv[3],"%d%c",&N,&junk)!=1 || N<=0
|| !argv[4] || sscanf(argv[4],"%d%c",&seed,&junk)!=1)
{ usage();
}
/* Look at the arguments specifying the method for producing the code. */
meth = argv+5;
if (!meth[0]) usage();
no4cycle = 0;
if (strcmp(meth[0],"evencol")==0 || strcmp(meth[0],"evenboth")==0)
{ method = strcmp(meth[0],"evencol")==0 ? Evencol : Evenboth;
if (!meth[1])
{ usage();
}
d = distrib_create(meth[1]);
if (d==0)
{ usage();
}
if (meth[2])
{ if (strcmp(meth[2],"no4cycle")==0)
{ no4cycle = 1;
if (meth[3])
{ usage();
}
}
else
{ usage();
}
}
}
else
{ usage();
}
/* Check for some problems. */
if (distrib_max(d)>M)
{ fprintf(stderr,
"At least one checks per bit (%d) is greater than total checks (%d)\n",
distrib_max(d), M);
exit(1);
}
if (distrib_max(d)==M && N>1 && no4cycle)
{ fprintf(stderr,
"Can't eliminate cycles of length four with this many checks per bit\n");
exit(1);
}
/* Make the parity check matrix. */
make_ldpc(seed,method,d,no4cycle);
/* Write out the parity check matrix. */
f = open_file_std(file,"wb");
if (f==NULL)
{ fprintf(stderr,"Can't create parity check file: %s\n",file);
exit(1);
}
intio_write(f,('P'<<8)+0x80);
if (ferror(f) || !mod2sparse_write(f,H) || fclose(f)!=0)
{ fprintf(stderr,"Error writing to parity check file %s\n",file);
exit(1);
}
return 0;
}
