C userspace programs

user/Makefile.inc

@@ -1,6 +1,5 @@
-ARCH ?= x86_64
-
-CFLAGS := -ffreestanding -Wall -Wextra -g -fcommon -nostdinc
+CFLAGS := -ffreestanding -Wall -Wextra -g -fcommon -nostdinc \
+          -isystem $(ROOT)/std/include -isystem $(ROOT)/ulib
 
 CURRENT_DIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
 

user/arch/x86_64/link.ld

@@ -1,17 +1,17 @@
 ENTRY(_start)
 
 SECTIONS {
-  . = 0x0000000000000000;
-
-  .rodata ALIGN(4K):
-  {
-    *(.rodata .rodata.*)
-  }
+  /* . = 0x0000000000000000; */
 
   .text ALIGN(4K):
   {
     *(.text .text.*)
   }
+  
+  .rodata (READONLY): ALIGN(4K)
+  {
+    *(.rodata .rodata.*)
+  }
 
   .data ALIGN(4K):
   {
@@ -20,6 +20,8 @@ SECTIONS {
 
   .bss ALIGN(4K):
   {
+    _bss_start = .;
     *(.bss .bss.*)
+    _bss_end = .;
   }
 }

user/arch/x86_64/x86_64.mk

@@ -1,18 +1,5 @@
-CC := x86_64-elf-gcc
-LD := x86_64-elf-ld
-
-CFLAGS += -m64 \
-					-fPIE \
-					-mno-80387 \
-					-mno-mmx \
-					-mno-sse \
-					-nostartfiles \
-					-nostdlib \
-					-mno-sse2 \
-					-mno-red-zone \
-					-fno-stack-protector \
-					-fno-stack-check \
-					-Os \
+include $(ROOT)/mk/user/x86_64.mk
+include $(ROOT)/mk/arch/toolchain-x86_64.mk
 
 LDFLAGS += -m elf_x86_64 \
 					-pie \

user/hello/Makefile

@@ -14,9 +14,9 @@ OBJ := $(call GET_OBJ, $(SRCFILES))
 
 all: $(TARGET)
 
-hello: $(OBJ)
+$(TARGET): $(OBJ)
 	$(LD) $^ $(LDFLAGS) -o $@
-	echo $(realpath hello) >> $(FILES)
+	echo $$(realpath $(TARGET)) >> $(FILES)
 
 clean:
 	rm -f $(OBJ) $(TARGET)

user/hello/hello.s

@@ -11,8 +11,7 @@ _start:
   movq $1, %rax
   lea STRING(%rip), %rdi
   lea STRING_LEN(%rip), %rsi
-  syscall
+  int $0x80
 
   movq $2, %rax
-  syscall
-
+  int $0x80

user/init/.gitignore

@@ -0,0 +1,2 @@
+*.o
+init

user/init/Makefile

@@ -0,0 +1,24 @@
+include $(ROOT)/mk/grabsrc.mk
+include ../Makefile.inc
+
+.PHONY: all clean
+
+TARGET := init
+
+LDFLAGS += -L$(ROOT)/ulib -l:libulib.a
+
+SRCFILES := $(call GRABSRC, .)
+CFILES := $(call GET_CFILES, $(SRCFILES))
+OBJ := $(call GET_OBJ, $(SRCFILES))
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+all: $(TARGET)
+
+$(TARGET): $(OBJ)
+	$(LD) $^ $(LDFLAGS) -o $@
+	echo $$(realpath $(TARGET)) >> $(FILES)
+
+clean:
+	rm -f $(OBJ) $(TARGET)

user/init/main.c

@@ -0,0 +1,6 @@
+#include <system/system.h>
+
+void main(void) {
+  sys_debugprint("Hello world from userspace in C");
+}
+