Wut ? C

AviStruct* GetVideoInfo(char*file)
{
    AviStruct* MyVideo = (AviStruct*)s_alloc(sizeof(AviStruct));
    FILE*f = fopen(file,"rb");
    if (f)
    {
        unsigned int dwRate;
        unsigned int dwScale;
        unsigned int dwLength;
        fseek(f,0x84, SEEK_SET );
        fread(&dwRate,4,1,f);
        fseek(f,0x80, SEEK_SET );
        fread(&dwScale,4,1,f);
        fseek(f,0x8C, SEEK_SET );
        fread(&dwLength,4,1,f);
        fseek(f,0x40, SEEK_SET );
        fread(&MyVideo->width,4,1,f);
        fseek(f,0x44, SEEK_SET );
        fread(&MyVideo->height,4,1,f);
        MyVideo->fFps = (float)((float)(dwRate)/(float)(dwScale));
        MyVideo->fDuration = (float)((float)(dwLength)/(float)(MyVideo->fFps));
        return MyVideo;

    }
    return 0x0;
}

good joob discovering the RIFF structure

AviStruct*
GetVideoInfo(char* file)
{
  AviStruct* MyVideo = (AviStruct*)s_alloc(sizeof(AviStruct));
  fread(MyVideo, sizeof(AviStruct), 1, f);
  return MyVideo;
}

Fixed.

>>3
It won't work, noob.
if you look at the fseek, you'll see that it isn't right at the beginning of an avi file.

>>4
Arguably, you could reconstruct your AviStruct structure to have padding to account for the offset. And arguably any performance loss it causes would be insignificant since the operation which loads it is only done once per file and isn't a limiting factor.

Also, neither of you close your fucking file handle.

>>4
funny how you call him a noob for the lack of a fseek at the start but have no idea that YOU DONT NEED TO GODDAMN CAST IT TO FLOAT SO MANY FUCKING TIMES


MyVideo->fFps = (float)((float)(dwRate)/(float)(dwScale));
I lol'd

>>7

I remember coming across the following fragment of code when I was grading assignments from first year CS students:

x = 2;
x = 2; // just to make sure
x = 2; // one more time wouldn't be a bad idea

>>8

RISC processor!

>>8
he doesn't trust the compiler, he'd go far as a programmer


for(;;);
for(;;);
for(;;);
Just to make sure

>>1

return 0x0
what.

>>11
he casts shit to float constantly yet forgot to cast (void*) to 0

>>12
he forgot to desallocate his MyVideo in case the file doesn't exist
he doesn't fclose
there's extra float conversion
here's a fixed code for you
AviStruct* GetVideoInfo(char*file)
{
    AviStruct* MyVideo = (AviStruct*)s_alloc(sizeof(AviStruct));
    FILE*f = fopen(file,"rb");
    if (f)
    {
        unsigned int dwRate;
        unsigned int dwScale;
        unsigned int dwLength;
        fseek(f,0x84, SEEK_SET );
        fread(&dwRate,4,1,f);
        fseek(f,0x80, SEEK_SET );
        fread(&dwScale,4,1,f);
        fseek(f,0x8C, SEEK_SET );
        fread(&dwLength,4,1,f);
        fseek(f,0x40, SEEK_SET );
        fread(&MyVideo->width,4,1,f);
        fseek(f,0x44, SEEK_SET );
        fread(&MyVideo->height,4,1,f);
        MyVideo->fFps = ((float)(dwRate)/dwScale);
        MyVideo->fDuration = ((dwLength)/(MyVideo->fFps));
        fclose(f);
        return MyVideo;

    }
    //Could not open file
    freememory(MyVideo);
    return 0;
}

>>13
You can avoid calling fseek if your structure has the same structure of the file for the header but that would mean extra usage of memory.

>>12
You don't return (void*)0. you return NULL.

Also, f(set/get)pos, use it motherfucker.

How about checking dwRate and dwScale for zero, idiots.

Nice error checking everyone! Also I am impressed by your endian neutrality, and your capability to work on systems where an int is not 32 bits.

Maybe you could only allocate the memory if the file opening was successful? Just a little tip ;)

NIGGERS

There are piles of things wrong with >>1's code post. First, it puts main functionality inside an "if successful" branch, when obviously error handling should be in the further indented bit. Second, it pointlessly abuses fseek() to read bits and pieces of a header when a read into a byte buffer would be clearer (and a little bit faster too).

Third, and most important, it reads integers in a non-portable way. INTEGER ENDIANNESS MOTHERFUCKER, have you heard of it?

I'd do the same somewhat like this:


unsigned int uintFromFile(FILE *f, off_t offset)
{
    int n = fseek(f, offset, SEEK_SET);
    if(n != 0) goto iofail;
    uint8_t buf[sizeof(unsigned int)];
    n = fread(buf, sizeof(unsigned int), 1, f);
    if(n != 1) goto iofail;
    // assuming little-endian, i.e. RIFF byte order
    return buf[0] | (((unsigned)buf[1]) << 8) | (((unsigned)buf[2]) << 16) | (((unsigned)buf[3]) << 24);

iofail:
    if(errno == 0) {
        fprintf(stderr, "%s: short read\n", __FUNCTION__);
    } else {
        fprintf(stderr, "%s: IO failure: %s\n", __FUNCTION__, strerror(errno));
    }
    exit(EXIT_FAILURE);
    // or some other appropriate error handling mechanism   
}

This moves error handling out of the main functionality and into a reusable function (we'll assume that you'd like to read other bits from the AVI header too), and narrows down the error cases so that the caller doesn't need to bother their little noggin too much.

You could also change the prototype to int uintFromFile(unsigned int *result_p, FILE *f, off_t offset) and store the output integer in *result_p and return an error indicator (0 on success, errno on failure, for instance).

>>18
GOTO━━━━━━(ﾟ∀ﾟ)━━━━━━ !!!!!

>>19
Gotos in a strictly downward direction are kosher. Just ask your local rabbi. (unless he's busy welding his foreskin golem.)

>>20
What are you getting so defensive about?  Don't tell me you know, in your heart, that your code is actually the incarnation of Abelson?

>>15
You're a fucking idiot for not knowing they're the same damn thing.

NULL is a #define for (void*)0

>>13
still forgetting the fact hes returning a pointer, this isnt C++ where 0 == NULL, wait is it?

>>17
1. cant be fucked, we're all trolls here
2. tiredness
3. learning java

>>18
fail for assuming endianness, enjoy your reversed bits

plus, you should check the size of the integer via a #define as provided by the system headers then using #define to create the correct structure and function, your function adds too much overhead at runtime

>>22
Suck a cock, fool. The only thing that is assumed there is the endianness of 4-byte integers in the file, which is generally specified by the format!

The only thing wrong with the code in >>18 (why doesn't /prog/ have IDs anymore?) is that it should declare the buffer to be exactly 4 bytes long -- since the file format defines uints as 4 bytes. It's subsequently converted to an unsigned int in the return -- see the shifts and ors?

>>21
Everything on /prog/ is criticism by default. Therefore there is no "being defensive" on /prog/.

>>23
what's that? i can't hear you with that cock in your mouth

trolled

>>25
YHBT

>>26
YHBT

>>1
What coding style is that where he capitalises function/variable names?
Im a programming noob and most of the professional code I've seen on google/cpan/directx sdk uses camelback notation.

IE: getVideoInfo( char* file )

>>28
Nigger style

>>28
Get out, haskellFag.

I still wonder why people hate shitCase. It's the same as CamelCase except for the lack of the completely useless capitalization of the first letter.

>>31
CamelCase is periodic, shitCase isn't. Observe:

^/\/\/\/\/\/\/\/
NOT BEAUTY.
\/\/\/\/\/\/\/\/
NOT BEAUTY either, but at least you can make longer patterns of it.

Also, shitCase makes it look that the typist is hopelessly stuck between the convention of variables beginning in lowercase and readability.

Bottom line is, haskellSucks.

longer patterns of it
class DrugStrengthFormCountryManufacturerPharmacyCopayProductPriceFactory
{
    public DrugStrengthFormCountryManufacturerPharmacyCopayProductPrice
        getSalesOrderProductSupplierCopayDrugStrengthFormCountryManufacturerPharmacyCopayProductPrice(
            SecurityContext securityContext,
            SalesOrderProductSupplier salesOrderProductSupplier,
            Organization copay)
    {
        /* some code here */
    }
}

>>33
WorseThanFailure is made of niggers and Microsoft shills, and you're a faggot for reading it.

>>33
ENTERPRISE!

>>34
Takes one to know one, faggot.

>>36
That's a brilliant come-back, that is, especially given that the fact >>34 recognised the quote was already an admission of his own faggotry, making your post little more than an agreement.
gb2 middle school

>>33
AHAHAHA you read that shit too?

>>34
How do you recognize that excerpt from WorseThanFailure?

>>39
This has already been discussed in >>36-37.