kernel/fxf and launcher: Add and use launch_fxf_from_disk syscall

applications/launcher/main.asm

@@ -65,7 +65,12 @@ button_click_event:
     ; terminal
     cmp r1, 0
     ifz mov r0, terminal_button_fxf
-    ifz call launch_fxf
+    ifz mov r1, 0
+    ifz mov r2, 0
+    ifz mov r3, 0
+    ifz mov r4, 0
+    ifz mov r5, 0
+    ifz call launch_fxf_from_disk
 
     ret
 
@@ -101,7 +106,5 @@ button_text: data.strz "  "
 icons:
     #include "icons.inc"
 
-    #include "launch.asm"
-
     #include "../../../fox32rom/fox32rom.def"
     #include "../../fox32os.def"

fox32os.def

@@ -8,6 +8,7 @@ set_current_disk_id:       jmp [0x0000081C]
 
 ; FXF jump table
 parse_fxf_binary:          jmp [0x00000910]
+launch_fxf_from_disk:      jmp [0x00000914]
 
 ; task jump table
 new_task:                  jmp [0x00000A10]

kernel/fxf/fxf.asm

@@ -20,6 +20,7 @@ parse_fxf_binary:
 
 fxf_magic: data.strz "FXF"
 
+    #include "fxf/launch.asm"
     #include "fxf/reloc.asm"
 
 const FXF_CODE_SIZE:   0x00000004

kernel/fxf/launch.asm

@@ -1,11 +1,16 @@
-; FXF launcher helper routines
+; FXF launching routines
 
-; launch an FXF binary from a file name
+; launch an FXF binary from a file on disk
 ; inputs:
-; r0: pointer to FXF binary name
+; r0: pointer to FXF binary name (8.3 format, for example "testfile.fxf" or "test.fxf")
+; r1: argument 0
+; r2: argument 1
+; r3: argument 2
+; r4: argument 3
+; r5: argument 4
 ; outputs:
 ; none
-launch_fxf:
+launch_fxf_from_disk:
     push r0
     push r1
     push r2
@@ -39,6 +44,19 @@ launch_fxf:
     ifz jmp allocate_error
     mov [launch_fxf_stack_ptr], r0
 
+    ; push the arguments to the task's stack
+    mov r4, rsp
+    mov rsp, [launch_fxf_stack_ptr]
+    add rsp, 65536 ; point to the end of the stack (stack grows down!!)
+    push r5
+    push r4
+    push r3
+    push r2
+    push r1
+    sub rsp, 65516
+    mov [launch_fxf_stack_ptr], rsp
+    mov rsp, r4
+
     ; relocate the binary
     mov r0, [launch_fxf_binary_ptr]
     call parse_fxf_binary

kernel/main.asm

@@ -27,6 +27,7 @@ jump_table:
     ; FXF jump table
     org.pad 0x00000110
     data.32 parse_fxf_binary
+    data.32 launch_fxf_from_disk
 
     ; task jump table
     org.pad 0x00000210