Visual Studio: Difference between revisions

 

MinGW32's objcopy should do the job (parameters go something like this: -x -g -X -S -Obinary kernel.bin). But you don't have to strip any information from PE file, the other option is to set section alignment in memory to 0x200 which is generally equal to the section alignment on disk and do some math:

mov eax, [es:0x3c] ; PE header pointer in MZ header

mov ecx, [es:eax+0x28] ; AddressOfEntryPoint in PE header

 

where es is loaded with base address of your [[PE Binaries|PE]] file in memory, ecx will be loaded with the entry point relative to base address of PE file. Of course, if this is protected mode with a flat 4GB address space, use a register instead of using ES.

* On the '''GDB startup commands''' tab, under ''The following GDB commands will be run AFTER selecting a target:'' enter the following

 

symbol-file kernel.elf

add-symbol-file boot_sect.elf 0x7c00

directory $(RemoteSourceDir)/src

: These will load the symbols for your kernel and bootsector respectively, allowing you to debug through the sourcecode in your debugger.

== Some basic definitions: ==

 

#define EXPORT EXTERN __declspec(dllexport) // exported from DLL

#define IMPORT EXTERN __declspec(dllimport) // imported from DLL

}

}

 

I use these to create functions that end up with reasonably undecorated names like <code>_SomeFunction@8</code> instead of <code>?@SomeFunction@YAKK000I@@Z</code> (as a __cdecl normal function would be named...) The macros also allow easy import and export from a DLL.

To be booted by GRUB, you can make your kernel multiboot. THis involves the embedding of a multiboot header in the first 8K of the image.

This can be done as follows:

//Entry point goes here

 

(uint32_t)&entry - BASE_ADDR + LOADBASE

};

 

== The Rebase Utility ==

 

This is why if you intend to do 64 bit development in MSVC++ you should have an external assembly layer (seperate versions for 32 bit and 64 bit), or use somewhat more limited intrinsics, and for asm if you want to avoid name decoration you need to declare them in a header file like this:

#ifdef __cplusplus //if this is C++

extern "C" { //declare as C functions

} //and if it was C++ we need to close the brackets

#endif

And in your asm layer:

BITS 32 ;32 bit version

@disable@0:

cli

ret ;No decoration at all

 

== Intrinsics ==