A Brainfuck Interpreter on UEFI Shell (Requirements: gnu-efi)

main.c

#include <efi.h>
#include <efilib.h>

#define MEMORY_SIZE 30000
typedef unsigned char byte;
byte memory[MEMORY_SIZE] = {0};
unsigned long memoryIndex = 0;

EFI_STATUS efi_main(EFI_HANDLE ImageHandle , EFI_SYSTEM_TABLE* SystemTable) {
  INTN Argc, i;
  CHAR16 **Argv;

  InitializeLib(ImageHandle, SystemTable);
  Argc = GetShellArgcArgv(ImageHandle, &Argv);

  if (Argc != 2) {
    Print(L"Invalid Argument\n");
    return EFI_SUCCESS;
  }

  for (i = 0; i < StrLen(Argv[1]); i++) {
    switch(Argv[1][i]) {
      case '>': memoryIndex++; break;
      case '<': memoryIndex--; break;
      case '+': memory[memoryIndex]++; break;
      case '-': memory[memoryIndex]--; break;
      case '.': Print(L"%c", memory[memoryIndex]); break;
      case '[': if (memory[memoryIndex] == 0) while (Argv[1][i] != ']') i++; break;
      case ']': if (memory[memoryIndex] != 0) while (Argv[1][i] != '[') i--; break;

      default: break;
    }
  }
  Print(L"\n");
  return EFI_SUCCESS;
}

Makefile

ARCH = $(shell uname -m | sed s,i[3456789]86,ia32,)
OBJS = main.o
TARGET = main.efi
EFIINC = /usr/include/efi
EFIINCS = -I$(EFIINC) -I$(EFIINC)/$(ARCH) -I$(EFIINC)/protocol
EFILIB = /usr/lib
EFI_CRT_OBJS = $(EFILIB)/crt0-efi-$(ARCH).o
EFI_LDS = $(EFILIB)/elf_$(ARCH)_efi.lds
CFLAGS = $(EFIINCS) \
          -fno-stack-protector \
          -fpic \
          -fshort-wchar \
          -mno-red-zone \
          -Wall

ifeq ($(ARCH),x86_64)
	CFLAGS += -DEFI_FUNCTION_WRAPPER
endif

LDFLAGS = -nostdlib \
          -znocombreloc \
          -T $(EFI_LDS) \
          -shared \
          -Bsymbolic \
          -L $(EFILIB) \
          $(EFI_CRT_OBJS)

all: $(TARGET)

%.so:$(OBJS)
	ld $(OBJS) $(LDFLAGS) -o $@ -lefi -lgnuefi

%.efi: %.so
	objcopy -j .text -j .sdata -j .data -j .dynamic \
		-j .dynsym -j .rel -j .rela -j .reloc \
		--target=efi-app-$(ARCH) $^ $@