SKAS4 - Macroize stub system call execution loop

index e730772..890dc50 100644
@@ -1,52 +1,45 @@
 #include "uml-config.h"
 #include "as-layout.h"
 
+#define PROCESS_LIST \
+	/* load pointer to first operation */ \
+	mov	$(ASM_STUB_DATA + 8), %esp; \
+1: \
+	/* load length of additional data */ \
+	mov	0x0(%esp), %eax; \
+	/* if(length == 0) : end of list */ \
+	/* write possible 0 to header */ \
+	mov	%eax, ASM_STUB_DATA + 4; \
+	cmpl	$0, %eax; \
+	jz	2f; \
+	/* save current pointer */ \
+	mov	%esp, ASM_STUB_DATA + 4; \
+	/* skip additional data */ \
+	add	%eax, %esp; \
+	/* load syscall-# */ \
+	pop	%eax; \
+	/* load syscall params */ \
+	pop	%ebx; \
+	pop	%ecx; \
+	pop	%edx; \
+	pop	%esi; \
+ 	pop	%edi; \
+	pop	%ebp; \
+	/* execute syscall */ \
+	int	$0x80; \
+	/* check return value */ \
+	pop	%ebx; \
+	cmp	%ebx, %eax; \
+	je	1b; \
+2: \
+	/* save return value */ \
+	mov	%eax, ASM_STUB_DATA;
+
 	.globl syscall_stub
 .section .__syscall_stub, "x"
 
 	.globl batch_syscall_stub
 batch_syscall_stub:
-	/* load pointer to first operation */
-	mov	$(ASM_STUB_DATA+8), %esp
-
-again:
-	/* load length of additional data */
-	mov	0x0(%esp), %eax
-
-	/* if(length == 0) : end of list */
-	/* write possible 0 to header */
-	mov	%eax, ASM_STUB_DATA+4
-	cmpl	$0, %eax
-	jz	done
-
-	/* save current pointer */
-	mov	%esp, ASM_STUB_DATA+4
-
-	/* skip additional data */
-	add	%eax, %esp
-
-	/* load syscall-# */
-	pop	%eax
-
-	/* load syscall params */
-	pop	%ebx
-	pop	%ecx
-	pop	%edx
-	pop	%esi
- 	pop	%edi
-	pop	%ebp
-
-	/* execute syscall */
-	int	$0x80
-
-	/* check return value */
-	pop	%ebx
-	cmp	%ebx, %eax
-	je	again
-
-done:
-	/* save return value */
-	mov	%eax, ASM_STUB_DATA
-
+	PROCESS_LIST
 	/* stop */
 	int3

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