use printf

Author: h908714124

draft/draft.c

@@ -7,69 +7,14 @@
 #include <sys/syscall.h>
 #include <sys/types.h>
 
-char* in;
-char* out;
-
-int get_zero() {
-	int result = 128;
-	while(true) {
-		result = result / 2;
-		if (result == 16) {
-			return 0;
-		}
-	}
-	return 1;
-}
-
-int get_one() {
-	int result = 128;
-	while(true) {
-		result = result / 2;
-		if (result == 8) {
-			return 1;
-		}
-	}
-	return 2;
-}
-
-int get_two() {
-	int result = 128;
-	while(true) {
-		result = result / 2;
-		if (result == 4) {
-			return 2;
-		}
-	}
-	return 1;
-}
-
-int get_three() {
-	int result = 128;
-	while(true) {
-		result = result / 2;
-		if (result == 32) {
-			return 3;
-		}
-	}
-	return 2;
-}
-
 int main(int argc, char *argv[])
 {
-	in = malloc(4);
-	out = malloc(4);
-	in[0] = '0';
-	in[1] = 'x';
-	in[2] = 'a';
-	in[3] = '\n';
-	int zero = get_zero();
-	int one = get_one();
-	int two = get_two();
-	int three = get_three();
-	out[zero] = in[zero];
-	out[one] = in[one];
-	out[two] = in[two];
-	out[three] = in[three];
-	syscall(__NR_write, 1, out, 4);
-	return 0;
+	char message[3];
+	message[0] = 0x41;
+	message[1] = 0x55;
+	message[2] = 0x41;
+	printf("%.*s", 3, message);
+	fflush(stdout);
+	syscall(__NR_exit, 0);
+	//return 0;
 }

group3/Makefile

@@ -1,6 +1,5 @@
 default:
-	$(CC) group3.s -c -g
-	$(LD) -o group3 group3.o -e main
+	$(CC) group3.s -g -o group3 -e main
 
 clean:
 	@rm -f group3.o group3

group3/group3.s

@@ -145,7 +145,7 @@ close:
 	enter
 	push_all
 	mov	$CLOSE, %rax
-	lea	fh, %rdi
+	mov	fh, %rdi
 	syscall
 	pop_all
 	return
@@ -154,11 +154,11 @@ munmap:
 	enter
 	push_all
 	mov	$MUNMAP, %rax
-	lea	inbuf, %rdi
+	mov	inbuf, %rdi
 	mov	file_size(%rip), %rsi
 	syscall
 	mov	$MUNMAP, %rax
-	lea	out, %rdi
+	mov	out, %rdi
 	mov	file_size(%rip), %rsi
 	syscall
 	pop_all
@@ -192,14 +192,12 @@ print_lines_loop:
 	test	%r9, %r9
 	jz	print_lines_write_line
 	write	linebuf(%rip), $3
-	writeln
 print_lines_write_line:
 	mov	linebuf(%rip), %r10
 	add	$2, %r10			# skip two chars from linebuf
 	movb	$0x9, (%r10)			# replace third char with a tab
 	sub	$2, %rax
 	write	%r10, %rax
-	writeln
 	inc	%rbx
 	cmp	file_size(%rip), %rbx
 	jl	print_lines_loop
@@ -222,6 +220,7 @@ main:
 	mov	%rax, linebuf(%rip)
 	call	init_file
 	call	print_lines
+	call 	flush
 
 	call	close
 	call	munmap

print_int/Makefile

@@ -1,20 +1,17 @@
 print_int:
-	$(CC) main.s -c -o print_int.o
-	$(LD) -e main -o print_int print_int.o
+	$(CC) main.s -o print_int
 
 check: print_int
 	./print_int | md5sum | grep -q ^3cca2fa && printf "\033[1;32m[OK]\033[0m\n"
 
 write:
-	$(CC) write.s -c -o write.o
-	$(LD) -e main -o write write.o
+	$(CC) write.s -o write
 
 check_write: write
 	./write | grep -q '^ABC$$' && printf "\033[1;32m[OK]\033[0m\n"
 
 strcmp:
-	$(CC) strcmp.s -c -o strcmp.o
-	$(LD) -e main -o strcmp strcmp.o
+	$(CC) strcmp.s -o strcmp
 
 check_strcmp: strcmp
 	./strcmp | md5sum | grep -q ^00350de && printf "\033[1;32m[OK]\033[0m\n"

print_int/main.s

@@ -40,6 +40,9 @@ main:
 	log	%rdx
 	log	%rsi
 
+	call	flush
+	call	exit
+
 exit:
 	movq	$EXIT, %rax
 	movq	$0, %rdi

print_int/print_int.s

@@ -86,9 +86,21 @@
 	pop	%rsi
 	.endm
 
+	.data
+	format: .asciz "%.*s\n"
+
 	.text
 	.globl main
 
+flush:
+	enter
+	push_all
+	xor	%eax, %eax
+	mov	stdout(%rip), %rdi
+	call	fflush
+	pop_all
+	return
+
 write_char_debug:
 	enter
 	push_all
@@ -133,11 +145,11 @@ write_string:
 	enter
 	push_all
 	push	%rax
-	mov	24(%rbp), %rsi			# param: address
-	mov	16(%rbp), %rdx			# param: size
-	mov	$WRITE, %rax
-	mov	$STDOUT, %rdi
-	syscall
+	lea	format(%rip), %rdi
+	mov	24(%rbp), %rdx			# param: address
+	mov	16(%rbp), %rsi			# param: size
+	mov	$0, %rax			# number of vector arguments
+	call	printf
 	pop	%rax
 	pop_all
 	return
@@ -179,9 +191,6 @@ print_int_pop_loop:
 	test	%rcx, %rcx
 	jnz	print_int_pop_loop
 
-	movb	$0xa, -48(%rbp, %rdx)
-	inc	%rdx
-
 	lea	-48(%rbp), %rsi
 	write	%rsi, %rdx
 

print_int/strcmp.s

@@ -33,6 +33,7 @@ main:
 	mov	$2, %rax
 	strcmp	%rdi, %rsi, $3
 	log 	%rax
+	call	flush
 	call	exit
 
 exit:

print_int/write.s

@@ -12,13 +12,13 @@ main:
 	movb	$0x41, -24(%rbp)
 	movb	$0x42, -23(%rbp)
 	movb	$0x43, -22(%rbp)
-	movb	$0xa, -21(%rbp)
 	mov	%rbp, %rsi
 	sub	$24, %rsi
 	mov	%rsi, %rax
 	sub	$24, %rax
-	memcpy	%rsi, %rax, $4
-	write 	%rax, $4
+	memcpy	%rsi, %rax, $3
+	write 	%rax, $3
+	call	flush
 	call	exit
 
 exit: