hi,
I have made a small C program that make use of malloc and free for processing bitmap images. when i try to run the program, I am getting a error something like
*** glibc detected *** free(): invalid next size (normal): 0x0000000000503e70 ***
I am not sure of which free() is causing this error.
Can anybody of you please tell me,what is the reason for this? and how can I get rid of this?
Any help will be appreciated.
linux 2.6.11.4-21.11-default #1 Thu Feb 2 20:54:26 UTC 2006 x86_64 x86_64 x86_64 GNU/Linux
gcc version 3.3.5 20050117 (prerelease) (SUSE Linux)
glib GNU C Library stable release version 2.3.4 (20050218), by Roland McGrath et al.
here is part of my program
main()
{
struct tt
{
char a[54];
}g;
struct ss
{
int a[54];
}e;
char *f;
char *b,*chr;
long p=0,q=0,i=0,j=0;//,r=0;
long r1=0,r2=0,z1=0,r3=0,r4=0;//width calculation
int l=0;
int k=0,flag=0,flag1=0,flag2=0;
//char ch=' ';
FILE *fp,*fp1;
fp=fopen("paradise.bmp","rb");
fp1=fopen("hi1.bmp","w");
fread(&g,54,1,fp);
for(i=0;i<=53;i++)
{
if(g.a<0)
e.a=255+g.a+1;
else
e.a=g.a;
printf(" %d ",e.a);
}
r1=(e.a[18])+e.a[19]*256+e.a[20]*256*256+e.a[21]*256*256*256;
printf("\n*******r1=%ld*********\n",r1);
//cheking for zero padding
if(r1%4==0)
{
printf("\n********r1=%ld******\n",r1);
//no change;
}
else if(r1%3==0)
{
z1=r1;
flag1=2;
}
else if(r1%2==0)
{
z1=r1*2;
//printf("\n********z1=%ld******\n",z1);
flag1=1;
}
else
{
//flag1=0;
}
r1=r1*2;
r3=r1;
r2=e.a[22]+e.a[23]*256+e.a[24]*256*256+e.a[25]*256*256*256;
printf("\n*****r2=%ld******\n",r2);
r2=r2*2;
r4=r2;
printf("\n*****r4=%ld******\n",r4);
printf("\nhi %d\n",r1);
e.a[21]=(r1)/(16777216);
printf("\nhi ");
g.a[21]=e.a[21];
r1=r1-e.a[21]*256*256*256;
e.a[20]=(r1)/(65536);
g.a[20]=e.a[20];
r1=r1-e.a[20]*256*256;
e.a[19]=(r1)/(256);
g.a[19]=e.a[19];
r1=r1-e.a[19]*256;
e.a[18]=r1;
g.a[18]=e.a[18];
e.a[25]=(r2)/(16777216);
g.a[25]=e.a[25];
r2=r2-e.a[25]*256*256*256;
e.a[24]=(r2)/(65536);
g.a[24]=e.a[24];
r2=r2-e.a[24]*256*256;
e.a[23]=(r2)/(256);
g.a[23]=e.a[23];
r2=r2-e.a[23]*256;
e.a[22]=r2;
g.a[22]=e.a[22];
r1=e.a[2]+e.a[3]*256+e.a[4]*256*256+e.a[5]*256*256*256;
r1=(r1-z1)*2;
r2=r1;
e.a[37]=(r1)/(16777216);
g.a[37]=e.a[37];
r1=r1-e.a[37]*256*256*256;
e.a[36]=(r1)/(65536);
g.a[36]=e.a[36];
r1=r1-e.a[36]*256*256;
e.a[35]=(r1)/(256);
g.a[35]=e.a[35];
r1=r1-e.a[35]*256;
e.a[34]=r1;
g.a[34]=e.a[34];
e.a[5]=(r2)/(16777216);
g.a[5]=e.a[5];
r2=r2-e.a[5]*256*256*256;
e.a[4]=(r2)/(65536);
g.a[4]=e.a[4];
r2=r2-e.a[4]*256*256;
e.a[3]=(r2)/(256);
g.a[3]=e.a[3];
r2=r2-e.a[3]*256;
e.a[2]=r2;
g.a[2]=e.a[2];
fwrite(&g,54,1,fp1);
fclose(fp1);
fclose(fp);
printf("\n after calculation g.a[] is : ");
for(i=0;i<=53;i++)
printf(" %d ",g.a);
printf("\n hello");
printf("\n******r3=%ld*****\n",r3);
if((f=(char *)malloc(r3*3/4))==NULL)
{
printf("NO SPACE");
exit(0);
}
printf("\n f[] is : ");
for(p=0;p<r3*3/2;p++)
{
//*(f+p)=128;
f[p]=128;
printf(" %c ",f[p]);
}
printf("\n");
b=(char *)malloc(r3*3/4);
for(i=0;i<=r4;i++)
{
fp=fopen("paradise.bmp","rb");
if(i==0)
fseek(fp,54,0L);
else if((i+1)%2!=0 && flag1==1)
{
l++;
fseek(fp,54+(r3*3/4)*i+(l)*2,0L);
}
else
fseek(fp,54+(r3*3/4)*i+(l)*2,0L);
chr=(char *)malloc(r3*3/2);
fread(chr,r3*3/4,1,fp);
// if(i%2==0){
// for(r=0;r<r3*3/4;r++)
// }
fflush(fp);
fclose(fp);
for(p=0;p<(r3*3/4);p++)
{
// b[p]=e.a[p];
//*(b+p)=*(chr+p);
b[p]=chr[p];
}
//job of this loop is to make e.a[] a 582 byte array
for(p=0,q=0;p<(r3*3/4)*2;)
{
if(flag==1)
{
for(k=0;k<=2;k++)
{
//*(chr+p)=128;
chr[p]=128;
p++;
}
flag--;
}
else
{
for(k=0;k<=2;k++)
{
//*(chr+p)=*(b+q);
chr[p]=b[q];
q++;
p++;
}
flag++;
}
}
fp1=fopen("hi1.bmp","a+");
if(j%4==0)
{
fseek(fp1,54+j*(r3*3/4)*2,0L);
//write linefeed code here
for(k=0;k<(r3/2)*3;k++)
{
if(chr[k]==10)// ||*(chr+k)==13)
chr[k]=12;
}
fwrite(chr,(r3*3/4)*2,1,fp1);
j++;
}
else if((j-1)%4==0)
{
fseek(fp1,54+j*(r3*3/4)*2,0L);
for(k=0;k<(r3/2)*3;k++)
{
if(chr[k]==10 )//||*(chr+k)==13)
chr[k]=12;
}
fwrite(chr,(r3*3/4)*2,1,fp1);
j++;
}
if(j%4!=0 && (j-1)%4!=0)
{
fseek(fp1,54+j*(r3*3/4)*2,0L);
fwrite(f,(r3*3/4)*2,1,fp1);
fwrite(f,(r3*3/4)*2,1,fp1);
j+=2;
}
fflush(stdin);
fflush(fp1);
fclose(fp1);
free(f);
free(chr);
free(b);
f=(char *)malloc(r3*3/2);
for(p=0;p<r3*3/2;p++)
f[p]=128;
}
//}
if(i%2==0){
for(k=0;k<=1;k++)
if(flag2==0){
flag2=1;
fwrite(&e,582,1,fp1);
}
else{
fseek(fp1,55+582*1+582,0L);
fwrite(&e,582,1,fp1);
flag2=0;
}
}
else{
fwrite(&f,582,1,fp1);
flag1=2;
}
if(i==2||i==34){
if(i==34)
fputc(48,fp1);
else
fputc(102,fp1);
fputc(228,fp1);
fputc(6,fp1);
i=i+2;
}
else if(i==18 || i==22){
fputc(132,fp1);
fputc(1,fp1);
i++;
}
else
fputc(e.a,fp1);
}
Any help will be appreciated
Thanks & Regards
Vijay