Save stage

std_singos/stdio.h

@@ -0,0 +1,64 @@
+void print(string);
+
+void print(string)
+char* string;
+{
+#asm 
+    push bp
+    mov bp,sp
+    mov si,4[bp]
+    call 0x0000:0x7C47
+    pop bp
+#endasm
+}
+
+void print_stack(argument)
+{
+#asm 
+    push bp
+    mov bp,sp
+    push ds
+    push ax
+
+    mov ax, ss
+    mov ds, ax
+    mov si,4[bp]
+    call 0x0000:0x7C47
+    
+    pop ax
+    pop ds
+    pop bp
+#endasm
+}
+
+dump_ax_return(input)
+void* input;
+{
+    return input;
+}
+
+void dump_ax(input)
+void* input;
+{
+    // Force the variable in ax 
+    dump_ax_return(input)
+#asm
+    push bp
+    mov bp,sp
+    call 0x000:0x7C2A
+    pop bp
+#endasm
+}
+
+void print_newline()
+{
+    #asm 
+    printCRLF:
+    mov ah, #0xE
+    mov al, #13
+    int #0x10
+    mov al, #10
+    int #0x10
+    ret
+    #endasm
+}

std_singos/string.h

@@ -1,4 +1,5 @@
 void strcpy (destination, destination_segment, source, source_segment );
+void memcpy (destination, destination_segment, source, source_segment, num_bytes );
 
 void strcpy (destination, destination_segment, source, source_segment )
 char *destination;
@@ -52,3 +53,58 @@ int source_segment;
 
     #endasm
 }
+
+void memcpy (destination, destination_segment, source, source_segment, num_bytes)
+void *destination;
+int destination_segment;
+void *source;
+int source_segment;
+int num_bytes;
+{
+    #asm
+    ; copy two strings
+    ; IN si: the first (zero terminated) string
+    ; IN di: the second (zero terminated) string
+    ; OUT SF and ZF (same semantics as cmp)
+    
+    #define DESTINATION 4[bp];
+    #define DESTINATION_SEGMENT 6[bp];
+    #define SOURCE 8[bp];
+    #define SOURCE_SEGMENT 10[bp];
+    #define NUM_BYTES 12[bp];
+
+    push bp
+    mov bp,sp
+    memcpy:
+        push ax
+        push bx
+        push di
+        push es
+        push si
+        push ds
+        mov ax, DESTINATION; 
+        mov di, ax
+        mov ax, DESTINATION_SEGMENT; 
+        mov es, ax
+        mov ax, SOURCE; 
+        mov si, ax
+        mov ax, SOURCE_SEGMENT; 
+        mov ds, ax
+        mov cx, NUM_BYTES
+    .memcpy_loop:
+        movsb
+        cmp cx, 0x0
+        je .end
+        dec cx
+        jmp .loop
+    .memcpy_end:
+        pop ds
+        pop si
+        pop es
+        pop di
+        pop bx
+        pop ax
+        pop bp
+
+    #endasm
+}