Adds fgetat,fgettype,fgetmod. Seperates constants to multiple files

src/file.asm

@@ -5,57 +5,66 @@ extern	__INTERNAL_fmt
 extern	strlen
 extern	umask_get
 
-section .rodata
-	; Open flags
-	O_ACCMODE	equ	00000003q
-	O_RDONLY	equ	00000000q
-	O_WRONLY	equ	00000001q
-	O_RDWR		equ	00000002q
-	O_CREAT		equ	00000100q ;create if not exist
-	O_EXCL		equ	00000200q ;fail if file exists and O_EXCL+O_CREAT set
-	O_NOCTTY	equ	00000400q
-	O_TRUNC		equ	00001000q
-	O_APPEND	equ	00002000q
-	O_NONBLOCK	equ	00004000q
-	O_DSYNC		equ	00010000q
-	FASYNC		equ	00020000q
-	O_DIRECT	equ	00040000q
-	O_LARGEFILE	equ	00100000q
-	O_DIRECTORY	equ	00200000q
-	O_NOFOLLOW	equ	00400000q
-	O_NOATIME	equ	01000000q
-	O_CLOEXEC	equ	02000000q
-	__O_SYNC	equ	04000000q
-	O_SYNC		equ	(__O_SYNC | O_DSYNC)
-	O_PATH		equ	01000000q
-	__O_TMPFILE	equ	02000000q
-	O_TMPFILE	equ	(__O_TMPFILE | O_DIRECTORY)
-	O_NDELAY	equ	O_NONBLOCK
-	; Permission flags
-	S_IXOTH		equ	00001q ;o=x
-	S_IWOTH		equ	00002q ;o=w
-	S_IROTH		equ	00004q ;o=r
-	S_IRWXO		equ	00007q ;o=rwx
-	S_IXGRP		equ	00010q ;g=x
-	S_IWGRP		equ	00020q ;g=w
-	S_IRGRP		equ	00040q ;g=r
-	S_IRWXG		equ	00070q ;g=rwx
-	S_IXUSR		equ	00100q ;u=x
-	S_IWUSR		equ	00200q ;u=w
-	S_IRUSR		equ	00400q ;u=r
-	S_IRWXU		equ	00700q ;u=rwx
-	S_ISVIX		equ	0001000q ;sticky bit
-	S_ISGID		equ	0002000q ;set-group-ID bit
-	S_ISUID		equ	0004000q ;set-user-ID bit
-
-section .bss
-
 section .text
+	global	fstatat
+	global	fgetmod
 	global	fopen
 	global	fclose
 	global	fexist
 	global	fwrite
 
+;----- fstatat(*file[], *statBuffer[]) -----;
+; Gets information from a file, stores it into statBuffer[]
+; Return value: 0 if stats received, -errno otherwise
+; Used registers:
+;	rax*	(ret)
+;	rdi*	(arg) Pointer to file
+;	rsi*	(arg) Pointer to statBuffer
+;	rdx*	arg for syscall NR_newfstatat
+;	r10*	arg(flag) for syscall NR_newfstatat
+fstatat:
+	sub	rsp, SIZE_QWORD
+	mov	rax, NR_newfstatat
+	mov	rdx, rsi
+	mov	rsi, rdi
+	mov	rdi, AT_FDCWD
+	xor	r10, r10
+	syscall
+	add	rsp, SIZE_QWORD
+	ret
+
+;----- fgettype(*statBuffer[]) -----;
+; Gets file type from stat buffer
+; Return value: Permissions of given file or -EINVAL if statBuffer is invalid (first bit is 0)
+; Used registers:
+;	rax*	(ret)
+;	rdi	(arg) Pointer to statBuffer[]
+fgettype:
+	cmp	byte [rdi], 0
+	jne	.buffok
+	mov	rax, -EINVAL
+	ret
+	.buffok:
+	mov	rax, [rdi + ST_MODE]
+	and	rax, 0xF000
+	ret
+
+;----- fgetmod(*statBuffer[]) -----;
+; Gets file mode bits (file permissions) from stat buffer
+; Return value: Permissions of given file or -EINVAL if statBuffer is invalid (first bit is 0)
+; Used registers:
+;	rax*	(ret)
+;	rdi	(arg) Pointer to stat buffer
+fgetmod:
+	cmp	byte [rdi], 0
+	jne	.buffok
+	mov	rax, -EINVAL
+	ret
+	.buffok:
+	mov	rax, [rdi + ST_MODE]
+	and	rax, 0x0FFF
+	ret
+
 ;----- fopen(*file[], char mode) -----;
 ; Opens a file
 ; Return value: Pointer to opened file pointer, -errno otherwise