How can function like this be obtained?

Hello,
I have been provided a source to work with. And what it does is it patches a raw binary file.
I looked at the source and there is this function which can patch a float, byte or dword to an address. But the source for it is missing. My question is how can I make this function again?

I know it uses some operator overloading function and it can easily patch the variable and the exact size we would want. But I searched the net for every references but all has been in vain. So can you please help me out to recreate this function?

Examples:
InstallPatch<BYTE>(0x234, 0xFF);
InstallPatch<DWORD>(0x254, 12345);
InstallPatch<FLOAT>(0x839, 12.0f);

My interpretation of it prototype:
InstallPatch<DATA_TYPE>(ADDRESS, VALUE_ACCORDING_TO_DATA_TYPE)

Please define the word "patch".

Patch means to write data to an address.

Example of patching a byte, DWORD:

Code:

---

PatchByte(DWORD dwAddress, BYTE bData) // Overwrites the file content with 1 byte
{
        *(BYTE*)dwAddress = bData;
}

PatchDword(DWORD dwAddress, DWORD dwData) // Overwrites the file content with 4 bytes
{

        *(BYTE*)dwAddress = dwData;
}

---

Quote:

---

Originally Posted by Swoorup

Patch means to write data to an address.

---

The way you're referring to it, I'm not sure what kind of address you're talking about.

Code:

---

PatchByte(DWORD dwAddress, BYTE bData) // Overwrites the file content with 1 byte
{
    *(BYTE*)dwAddress = bData;
}

PatchDword(DWORD dwAddress, DWORD dwData) // Overwrites the file content with 4 bytes
{

        *(BYTE*)dwAddress = dwData;
}

---

Is the file loaded on memory? because the comments make no sence otherwise...

Yeah, its a memory address. I figured that The patching is done when it is at memory through dll.

This sounds very dubious. Please tell us more about what this is for, or forget about getting help.

Ok, I'll post some parts of the source code. Some of my own.

Here's the thing that patches a byte at given memory address.

Code:

---

void PatchByte(DWORD dwAddress, BYTE patch)
{
    DWORD dwProt;
        VirtualProtect((void*)dwAddress, sizeof(patch), PAGE_EXECUTE_READWRITE, &dwProt);
        *(BYTE*)dwAddress=patch;
        VirtualProtect((void*)dwAddress,  sizeof(patch), dwProt, &dwProt);
}

---

And another code to patch the floating point or DWORD at given address. (ALL 4 byte data types)

Code:

---

void PatchDWORD(DWORD dwAddress, DWORD patch)
{
    DWORD dwProt;
        VirtualProtect((void*)dwAddress, sizeof(patch), PAGE_EXECUTE_READWRITE, &dwProt);
        *(BYTE*)dwAddress=patch;
        VirtualProtect((void*)dwAddress,  sizeof(patch), dwProt, &dwProt);
}

---

For each data types, depending on the size of them, I have have to call PatchDWORD for patching DWORDs, FLOATS, ints which is equal to 4 bytes.
To write only a single byte/ char I would have to call PatchBYTE.

What I would like to do is:
By typing Patch<DWORD>(MemoryAddress, (DWORD)data) I would like to get DWORD (4 bytes) inserted into the specfic memory address.
And by type Patch<BYTE>(MemoryAddress, (BYTE)data) I would like to get a single byte or char inserted into the specific memory address.

Please don't be harsh on me. I cannot provide the whole source though. But here are some parts of it.

Code:

---

    for(int i = 0; i < 1; i++) CMemory::InstallPatch<DWORD>( ARR_CCoronaStore_63[i], ADDR_CCorona_Store + 0x63);
    for(int i = 0; i < 1; i++) CMemory::InstallPatch<DWORD>( ARR_CCoronaStore_64[i], ADDR_CCorona_Store + 0x64);
    for(int i = 0; i < 1; i++) CMemory::InstallPatch<DWORD>( ARR_CCoronaStore_65[i], ADDR_CCorona_Store + 0x65);


    CMemory::InstallPatch<BYTE>(0x544591, MAX_CORONAS);
    CMemory::InstallPatch<BYTE>(0x5425BA, MAX_CORONAS);

---

The syntax you are looking for is called a function template.

Yup, exactly thank you.

Sorry for the bump, but I got a question. Does the whole templete needs to be in header file?
I want to use it sources that includes it but I am getting a lot of compilation errors

The simple answer is yes.

Thank you :D

This smells suspiciously like an attempt at hacking.