Merge pull request #6 from alexs-sh/minor-updates

Minor updates

.github/workflows/build.yml

@@ -0,0 +1,16 @@
+name: Build
+on: [push]
+
+jobs:
+  linux:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Install tools
+        run: sudo apt-get -y install -y gcc make nasm
+
+      - name: Build
+        run: make os-image.bin

Makefile

@@ -7,12 +7,15 @@ C_SOURCES = $(wildcard kernel/*.c drivers/*.c cpu/*.c)
 HEADERS = $(wildcard kernel/*.h  drivers/*.h cpu/*.h)
 OBJ_FILES = ${C_SOURCES:.c=.o cpu/interrupt.o}
 
+CC ?= x86_64-elf-gcc
+LD ?= x86_64-elf-ld
+
 # First rule is the one executed when no parameters are fed to the Makefile
 all: run
 
 # Notice how dependencies are built as needed
 kernel.bin: boot/kernel_entry.o ${OBJ_FILES}
-	x86_64-elf-ld -m elf_i386 -o $@ -Ttext 0x1000 $^ --oformat binary
+	$(LD) -m elf_i386 -o $@ -Ttext 0x1000 $^ --oformat binary
 
 os-image.bin: boot/mbr.bin kernel.bin
 	cat $^ > $@
@@ -25,14 +28,14 @@ echo: os-image.bin
 
 # only for debug
 kernel.elf: boot/kernel_entry.o ${OBJ_FILES}
-	x86_64-elf-ld -m elf_i386 -o $@ -Ttext 0x1000 $^
+	$(LD) -m elf_i386 -o $@ -Ttext 0x1000 $^
 
 debug: os-image.bin kernel.elf
 	qemu-system-i386 -s -S -fda os-image.bin -d guest_errors,int &
 	i386-elf-gdb -ex "target remote localhost:1234" -ex "symbol-file kernel.elf"
 
 %.o: %.c ${HEADERS}
-	x86_64-elf-gcc -g -m32 -ffreestanding -c $< -o $@ # -g for debugging
+	$(CC) -g -m32 -ffreestanding -fno-pie -fno-stack-protector -c $< -o $@ # -g for debugging
 
 %.o: %.asm
 	nasm $< -f elf -o $@