Question

I have problem running and debugging this piece of code:

bool readSectionHeaders(char* path, int numOfSections, int peSectionsOff, IMAGE_SECTION_HEADER* out) {
    bool retr = false; //return value

    //open file
    FILE* file;
    file = fopen (path, "rb");
    if(file == NULL) {
        perror("WRG"); //TODO
        return false;
    }

    do { //do while(false) only for easier error correction

        //seek to first section
        fseek(file, peSectionsOff, SEEK_SET);

        //read all sections
        unsigned int count;
        IMAGE_SECTION_HEADER sectionHeaders[numOfSections];
        count = fread(sectionHeaders, sizeof(IMAGE_SECTION_HEADER), numOfSections, file);

        //check Bytes count
        if(count != sizeof(IMAGE_SECTION_HEADER)*numOfSections) {
            break;
        }

        //copy sections
        memcpy(out, sectionHeaders, count);

        //exit successfully
        retr = true;
    } while(false);

    //exit
    fclose(file);

    return retr;
}

What is strange is that it returns false even when it reads the file. I tried to debug it and here is the strangest part.

I go line by line until this one

if(file == NULL) {

Then even though file is not NULL it skips perror and moves to

return false;

But does not return at all.

I again go line by line until

retr = true;

where it seems to do something, however retr remains false.

Then it closes file and returns with false.

I have never come across something like this.
I tried cleaning project, rebuilding, even deleting files and redownloading them from subversion. Before using this function, I use similar one – I read PE headers. So I though a problem could be with reading the file but it doesn§t explain debug behavior.

After returning from function, I use perror and it writes No error.

I use mingw with QtCreator.

Thanks in advance.

Answer 1

Ok, this was both my and mingw’s problem. I’ve re-installed whole QtSDK with no effect. Then I installed different version of mingw and set qt creator up to use it. Now debugger works without problem. I’m not sure what happened but cerr << “TEST”; also stopped working with the old mingw and this is 100% correct.

As 111111 suggested, problem was with if break clause. I thought read returns number of bytes read and this was simply not true :).

Now it is working, thanks to 111111 for his suggestion :).