From:	DavMac AT iname DOT com (Davin McCall)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: help me with this bmp loader program please
Date:	Mon, 16 Aug 1999 05:19:09 GMT
Organization:	Monash Uni
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Easy. You declare "char *pix" in function "main" and pass it to
"GetBitmap" without actually setting it to a suitable value

	(eg:   char *pix = malloc(BIG_NUMBER); )

GetBitmap then stores values at the memory pointed to by pix, which
could be anywhere... your program crashes!

A better way of doing this would be to have:


int GetBitmap(char* file, char** pix, int *width, int * height);

("pix" parameter is now char **, not char *) and then in the code for
GetBitmap:

  
  *pix = malloc( paddedWidth * bmpheader.biHeight );

//********problem area *************//
   for(int i=0; i < bmpheader.biHeight; i++)
      fread((*pix)[i*paddedWidth] , paddedWidth,1 , bmpfile);
    /* notice change from "pix" to "{*pix)" in above line */
//************************************


Davin.

[original snipped]
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