Initial commit

kernel/GNUmakefile

@@ -0,0 +1,77 @@
+# This is the name that our final kernel executable will have.
+# Change as needed.
+override KERNEL := kernel.elf
+
+# It is highly recommended to use a custom built cross toolchain to build a kernel.
+# We are only using "cc" as a placeholder here. It may work by using
+# the host system's toolchain, but this is not guaranteed.
+ifeq ($(origin CC), default)
+CC := cc
+endif
+
+# Likewise, "ld" here is just a placeholder and your mileage may vary if using the
+# host's "ld".
+ifeq ($(origin LD), default)
+LD := ld
+endif
+
+# User controllable CFLAGS.
+CFLAGS ?= -O2 -g -Wall -Wextra -Wpedantic -pipe
+
+# User controllable linker flags. We set none by default.
+LDFLAGS ?=
+
+# Internal C flags that should not be changed by the user.
+override INTERNALCFLAGS :=   \
+	-I.                  \
+	-std=c11             \
+	-ffreestanding       \
+	-fno-stack-protector \
+	-fno-stack-check     \
+	-fno-pic             \
+	-mabi=sysv           \
+	-mno-80387           \
+	-mno-mmx             \
+	-mno-3dnow           \
+	-mno-sse             \
+	-mno-sse2            \
+	-mno-red-zone        \
+	-mcmodel=kernel      \
+	-MMD
+
+# Internal linker flags that should not be changed by the user.
+override INTERNALLDFLAGS :=    \
+	-Tlinker.ld            \
+	-nostdlib              \
+	-zmax-page-size=0x1000 \
+	-static
+
+# Use find to glob all *.c files in the directory and extract the object names.
+override CFILES := $(shell find ./ -type f -name '*.c')
+override OBJ := $(CFILES:.c=.o)
+override HEADER_DEPS := $(CFILES:.c=.d)
+
+# Default target.
+.PHONY: all
+all: $(KERNEL)
+
+limine.h:
+	curl https://raw.githubusercontent.com/limine-bootloader/limine/trunk/limine.h -o $@
+
+# Link rules for the final kernel executable.
+$(KERNEL): $(OBJ)
+	$(LD) $(OBJ) $(LDFLAGS) $(INTERNALLDFLAGS) -o $@
+
+# Compilation rules for *.c files.
+-include $(HEADER_DEPS)
+%.o: %.c limine.h
+	$(CC) $(CFLAGS) $(INTERNALCFLAGS) -c $< -o $@
+
+# Remove object files and the final executable.
+.PHONY: clean
+clean:
+	rm -rf $(KERNEL) $(OBJ) $(HEADER_DEPS)
+
+.PHONY: distclean
+distclean: clean
+	rm -f limine.h