Struct and file handling - c

Question

The program I am making must store the values in the text file on their respective variables. The problem seems to arise in the inner loop. I have the respective structs already defined. The program runs properly for the outer loop but when it proceeds in the inner loop, the file pointer does not read the proper values from the text file and outputs "0.0" and does not proceed with the processes from the outer loop altogether.
my input file looks something like this:
GENERAL
1 4
PANELS
1 2.1 3.1 4.1 5.1 6.1 7.1 1
2 2.2 3.2 4.2 5.2 6.2 7.2 2
1 2.21 3.21 4.21 5.21
2 2.22 3.22 4.22 5.22
3 2.3 3.3 4.3 5.3 6.3 7.3 0
4 2.4 3.4 4.4 5.4 6.4 7.4 4
1 2.41 3.41 4.41 5.41
2 2.42 3.42 4.42 5.42
3 2.43 3.43 4.43 5.43
4 2.44 3.44 4.44 5.44
MATERIAL
1 1000.0 2000.0 3000.0 4000.0
2 1010.0 2020.0 3030.0
3 1010.1 2020.2
CHB
1 10 20 30 2
2 11 22 33 1
these are just placeholders to see if they are stored. single digits are integers while floats have decimal points.
here is the code
typedef struct _open
{
int id;
double length;
double height;
double origX;
double origY;
int frames;
double thickness;
double E;
double v;
}CHBOpening;
typedef struct _panels
{
int id;
double length;
double height;
double origX;
double origY;
double origZ;
double angle;
int nOpenings;
int nReinforcement;
double *xReinf;
double sx;
double xReinf0;
CHBUnit *chb;
CHBOpening *openings[];
}CHBPanel;
typedef struct _chb
{
int nStories;
int nModes;
int nIter;
int nPanels;
CHBPanel *panels[];
}CHBStructure;
int ReadPanelBlock (FILE *fp, CHBStructure *S)
{
int i,j;
S->panels = malloc(S->nPanels*sizeof(CHBStructure));
for (i=0; i< S->nPanels; i++)
{
fscanf(fp,"%d",&S->panels[i].id);
fscanf(fp,"%lf",&S->panels[i].length);
fscanf(fp,"%lf",&S->panels[i].height);
fscanf(fp,"%lf",&S->panels[i].angle);
fscanf(fp,"%lf",&S->panels[i].origX);
fscanf(fp,"%lf",&S->panels[i].origY);
fscanf(fp,"%lf",&S->panels[i].origZ);
fscanf(fp,"%d",&S->panels[i].nOpenings);
if (S->panels[i].nOpenings > 0)
{
S->panels[i].openings = malloc(sizeof(CHBOpening)*S->panels[i].nOpenings);
for (j=0; j<S->panels[i].nOpenings;j++)
{
fscanf(fp,"%d",&S->panels[i].openings[j].id);
fscanf(fp,"%lf",&S->panels[i].openings[j].length);
fscanf(fp,"%lf",&S->panels[i].openings[j].height);
fscanf(fp,"%lf",&S->panels[i].openings[j].origX);
fscanf(fp,"%lf",&S->panels[i].openings[j].origY);
}
}
}
return 1;
}

Answer 1

When you allocate pannels you do
S->panels = malloc(S->nPanels*sizeof(CHBStructure));
The problem here is that you use sizeof(CHBStructure) instead of sizeof(CHBPanel). The problem with this is that sizeof(CHBStructure) < sizeof(CHBPanel), so you don't allocate enough memory for the data you read.
That will lead to writing out of bounds, and undefined behavior.
This is in addition to the "typo" in the input file, which will lead you to enter the inner loop when there's nothing to read.