added basic allocator

.gitignore

@@ -1,2 +1,3 @@
 .asm-lsp.toml
 build
+src/*.o

Makefile

@@ -1,28 +1,38 @@
 NASM = nasm
 LD = ld
 
-NASM_FLAGS := -felf64
+NASM_FLAGS := -felf64 -Isrc
 LD_FLAGS := --strip-all 
 
+DEBUG_LD_FLAGS := -g
+DEBUG_NASM_FLAGS := -g -F dwarf
+
+
 SRC_PATH := src
 OBJ_PATH := build/obj
 BIN_PATH := build/bin
 
+BIN_NAME := asm-game-of-life
+
 SRC_FILES := $(wildcard $(SRC_PATH)/*.asm)
 OBJ_FILES := $(patsubst $(SRC_PATH)/%.asm,$(OBJ_PATH)/%.o,$(SRC_FILES))
 
-all: make-build-dir $(BIN_PATH)/asm-game-of-life
+all: $(BIN_PATH)/$(BIN_NAME) | make-build-dir
+
+debug: NASM_FLAGS += $(DEBUG_NASM_FLAGS)
+debug: LD_FLAGS = $(DEBUG_LD_FLAGS)
+debug: $(BIN_PATH)/$(BIN_NAME) | make-build-dir
 
 make-build-dir:
 	mkdir -p $(OBJ_PATH)
 	mkdir -p $(BIN_PATH)
 
 
-$(BIN_PATH)/asm-game-of-life: $(OBJ_FILES)
+$(BIN_PATH)/$(BIN_NAME): $(OBJ_FILES) | make-build-dir
 	$(LD) $(LD_FLAGS) $^ -o $@
 
 
-$(OBJ_PATH)/%.o: $(SRC_PATH)/%.asm
+$(OBJ_PATH)/%.o: $(SRC_PATH)/%.asm | make-build-dir
 	$(NASM) $(NASM_FLAGS) $< -o $@
 
 clean:

src/alloc.asm

@@ -0,0 +1,23 @@
+%include "symbols.asm"
+
+section .bss
+	brk_pointer: RESQ 1
+section .text 
+
+global init_alloc
+init_alloc:; initialize allocator, optionaly return brk pointer in rax
+	mov rax, SYS_BRK
+	mov rdi, 0
+	syscall
+	mov [brk_pointer], rax
+	ret
+
+global alloc
+alloc:; Takes lenght of data in rdi and returns pointer in rax
+	mov rax, SYS_BRK
+	mov rcx, [brk_pointer]
+	push rcx
+	syscall; size already in rdi
+	mov [brk_pointer], rax
+	pop rax
+	ret

src/main.asm

@@ -1,19 +1,56 @@
-SYS_EXIT 	equ 60
+%include "symbols.asm"
-SYS_IOCTL	equ 16
-
-STDOUT		equ 1
-TIOCGWINSZ	equ 0x5413
 
 section .bss
+	multipurpuse_buf: RESB 8
 
-	str_buf: resb 4
+	term_rows: RESW 1
+	term_cols: RESW 1
 
 section .data
-
+	
 section .text
-global _start
 extern print_str
 extern unsigned_int_to_ascii
+extern init_alloc
+extern alloc
 
+global _start
 _start:
+	; get terminal dimensions
+	mov rax, SYS_IOCTL
+	mov rdi, STDOUT
+	mov rsi, TIOCGWINSZ
+	lea rdx, [multipurpuse_buf]
+	syscall
 	
+	mov word ax, [multipurpuse_buf]; rows are stored at offset 0
+	mov [term_rows], ax
+
+	mov word ax, [multipurpuse_buf+2]; cols are stored at offset 2
+	mov [term_cols], ax
+
+	; handle args
+	pop rcx; get argc (number of arguments)
+	cmp rcx, 1 
+	jle .no_arguments_provided
+	; TODO hanndle arguments
+	.no_arguments_provided:
+
+	call init_alloc
+
+	mov ax, [term_rows]
+	dec ax; one less than terminal size for statusbar
+	mov cx, [term_cols]
+	mul rcx
+	mov rdi, rax
+	call alloc
+	mov r15, rax; stores pointer to gameboard array
+
+
+
+	mov rax, SYS_EXIT
+    	mov rdi, 0             ; return code
+    	syscall
+
+	
+

src/str.asm

@@ -1,6 +1,4 @@
-SYS_WRITE equ 1
+%include "symbols.asm"
-STDOUT equ 1
-ASCII_ZERO 	equ 48
 
 section .text
 

src/symbols.asm

@@ -0,0 +1,9 @@
+SYS_EXIT 	equ 60
+SYS_IOCTL	equ 16
+SYS_WRITE 	equ 1
+SYS_BRK		equ 12
+
+STDOUT		equ 1
+TIOCGWINSZ	equ 0x5413
+
+ASCII_ZERO 	equ 48