Possible file format for patching binary files.

eptFile.h

/*
 * +------------------------+
 * | Executable Patch Table |
 * +------------------------+
 * (not necessarily for executables though)
 *
 * This file describes a possible file format for
 * patching binary files.
 *
 * I know, I know, there are already bsdiff and
 * bspatch, but hey, this one supports multiple
 * files! It's also just an idea of mine. :)
 * Also, if the patches are too big, you can use
 * bsdiff and provide a separate patch for each
 * executable file. With appropriate instructions
 * of usage, of course; to patch the right files!
 *
 * ©2017 Gustavo6046. MIT license.
 * For more info read:
 * https://opensource.org/licenses/MIT
 */

struct EPT_Header
{
    int length; // header length
    int applicableFiles; // variations of this patch (one per file)
    EFT_FileVariationDesc* variations; // make sure the binary length of this list equals length.
};

struct EPT_FileVariationDesc
{
    int lengthInHeader; // length inside header
    int nextVariationPos; // position of next header variation (from start of file) in header
    char* filename; // filename for which this patch applies; string length must equal lengthInHeader - 12
    int dataPosition; // absolute position (i.e. offset from start of file) of this variation's binary data
    int length; // length of this variation
};

struct EPT_Fragment
{
    int pos; // position from Start of File in the original file where this fragment applies.
    int overwriteLen; // length of the data overwritten in the original file (0 for insertion only).
    char* myData; // a bunch of bytes determining the data added to the same position after the
                  // optional overwriting step.
};

struct EPT_File
{
    EPT_Header fileHeader; // the header for this file.
    EPT_Fragment* binData; // a list of Patch Fragments: each is a fragment of
                           // binary data patched in a different location of
                           // the original file.
};