bf interpreter because lulz

assets/bf.js

@@ -0,0 +1,66 @@
+// exec_args: bf.js input_file optional_memsize
+let memsize = exec_args[2]|0;
+if (memsize <= 0) memsize = (system.maxmem() < 30000) ? system.maxmem()-256 : 30000;
+let nativePtr = undefined;
+try {
+    nativePtr = sys.malloc(memsize);
+}
+catch (e) {
+    printerrln("Could not allocate memory with size "+memsize);
+    return 10;
+}
+let stubHead = "let mx="+memsize+";"+
+"let fmod=function(a,b){return Number((a-(Math.floor(a/b)*b)).toPrecision(8));};"+
+"let ip=function(){p=fmod(p+1,mx)};"+
+"let dp=function(){p=fmod(p-1,mx)};"+
+"let iv=function(){sys.poke(p,fmod(sys.peek(p)+1,256))};"+
+"let dv=function(){sys.poke(p,fmod(sys.peek(p)-1,256))};"+
+"let p="+nativePtr+";"
+let translation = {
+    62: "ip();",
+    60: "dp();",
+    43: "iv();",
+    45: "dv();",
+    46: "sys.print(String.fromCharCode(sys.peek(p)));",
+    44: "sys.poke(p,sys.readKey());",
+    91: "while(sys.peek(p)!=0){",
+    93: "}"
+};
+if (exec_args[1] === undefined) {
+    printerrln("Usage: bf <path-to-BF-program>");
+    return 1;
+}
+let bfprg = "";
+try {
+    filesystem.open(_G.shell.getCurrentDrive(), exec_args[1], "R");
+    bfprg = filesystem.readAll(_G.shell.getCurrentDrive());
+}
+catch(e) {
+    printerrln(e);
+    sys.free(nativePtr);
+    return 1;
+}
+try {
+    // translate
+    let tprg = stubHead;
+    for (let k = 0; k < bfprg.length; k++) {
+        tprg += (translation[bfprg.charCodeAt(k)] || "");
+    }
+
+    // clear memory
+    for (let k = 0; k < memsize; k++) {
+        sys.poke(nativePtr+k, 0);
+    }
+
+    // run
+    execApp(tprg);
+}
+catch (e) {
+    printerrln(e);
+    return 1;
+}
+finally {
+    sys.free(nativePtr);
+}
+
+return 0;

assets/bf/99

@@ -0,0 +1,254 @@
+# 99 bottles of beer in Brainf*ck
+# Copyright (C) 2008 Raphael Bois
+# 1671 brainf*ck instructions.
+# Published under GPL v2
+
+Initialization
+++    Counter for loop (a)
+>+    unused
+>++   Counter for loop (b)
+>     Flag for 'no more'
+>+    Flag for not 'no more'
+>>>   (5) to (7) : temporary values
+++++++++++[->+>+>++++++++++<<<]>>>    10 10 100 in (8) (9) (10)
+>++++++++++   10 in (11)
+[-
+   >+++++           50  in (12)
+   >++++++++++      100 in (13)
+   >+++++++++++     110 in (14)
+   >++++++++        80  in (15)
+   >++++++++        80  in (16)
+   >+++             30  in (17)
+   >++++            40  in (18)
+   >+               10  in (19)
+   <<<<<<<<]
++
+>-- +             48  '0'   plus 1 in (12)
+>++ +             102 'f'   plus 1 in (13)
+>+++++ +          115 's'   plus 1 in (14)
+>-- +             78  'N'   plus 1 in (15)
+>++++ +           84  'T'   plus 1 in (16)
+>++ +             32  ' '   plus 1 in (17)
+>++++ +           44  comma plus 1 in (18)
+> +               10  LF    plus 1 in (19)
+
+stuff for writing parts of the song
+>+   select stuff
+>+   select stuff
+>+   write song part 3
+>++  write song part 1
+>+   write song part 2
+>+   Flag for 'end of song'
+>++  Flag for not 'end of song'
+
+All bytes are at val plus 1
+Go back to (7) with final initialization step (remove 1 to all bytes)
+[-<]
+
+<<<<<<< at (0)
+[ loop (a)
+-
+
+>> at (2)
+[ loop (b)
+
+  >>>>>>>> at (10)
+  [ start loop
+
+    <<<<<<< at (3)
+    [->[-]
+      print '(N|n)o more'
+      >>>>>>>>>>>.  '(N|n)'
+      <----.        'o'
+      >>>.          ' '
+      <<<--.        'm'
+      ++.           'o'
+      +++.+         'r'
+      <-.+          'e'
+      <<+<<<<<<<<
+    ]+> at (4)
+    [-<[-]>>>>> at (9)
+      prints number (using (9) and (10))
+      [>>>+<<<<+<+<+>>>-]<<<[->>>+<<<]> at (6)
+      [>>>>>>+<<<<<<-]>>>>>[[-]>.<]<<<<[>>>>>-<<<<<-]>> at (9)
+      [<<+<+<+>>>>-]<<<<[->>>>+<<<<]> at (6)
+      [>>>>>>+<<<<<<-]>>>>>>.<<<<<[>>>>>-<<<<<-] at (7)
+
+      memorize in (11) if (10) not 1
+      >>>[-<<<+<+>>>>]<<<<[->>>>+<<<<]>-[[-]>>>>+<<<<]<<< at (4)
+    ]+
+
+    >>>>>>>> at (12)
+    print ' bottle(s) of beer'
+    >>>>>.      ' '
+    <<<<----.    'b'
+    >----.       'o'
+    +++++..-     'tt'
+    <++++++++++. 'l'
+    -------.     'e'
+    <<[[-]>>>.<<<]>> 's' if (11)==1 ie if (10)!=1
+    >>>>.        ' '
+    <<<----.     'o'
+    <+.          'f'
+    >>>>.        ' '
+    <<<<----.    'b'
+    +++..+       'ee'
+    >+++.+       'r'
+
+    [>] at (20)
+
+    +>+>[->+<<-<-
+         print ' on the wall' DOT LF LF
+         <<<.            ' '
+         <<<----.        'o'
+         -.              'n'
+         >>>.            ' '
+         <<<++++++.      't'
+         <++.            'h'
+         ---.            'e'
+         >>>>.           ' '
+         <<<+++.         'w'
+         <----.          'a'
+         +++++++++++..   'll'
+         ------>----     reset to 'f' and 's'
+         >---------- ---------- ---------- -- sets (15) to 'N'
+
+         >>>++.--  DOT
+         >..       LF LF
+    >>>] at (22)
+
+    >>>[->[-]<<<<<<<[<]<[-]>>[>]>>>>>]+ if end of song reset bottles counter
+    >[-<[-] at (25)
+      <<<< at (21)
+      [->>[->+<<<<-
+           print ' on the wall' COMMA ' '
+           <<<.            ' '
+           <<<----.        'o'
+           -.              'n'
+           >>>.            ' '
+           <<<++++++.      't'
+           <++.            'h'
+           ---.            'e'
+           >>>>.           ' '
+           <<<+++.         'w'
+           <----.          'a'
+           +++++++++++..   'll'
+
+           ------>----     reset (13) and (14) to 'f' and 's'
+           >++++++++++ ++++++++++ ++++++++++ ++ sets (15) to 'n'
+
+           >>>.            comma
+           <.              ' '
+      >>>>>>]<<]< at (20)
+
+      [->>>>[-<<+< at (21)
+             <<<++.--       DOT
+             >.             LF
+
+             [<]<<<<<<<< at (3)
+             [->[-]<]+>  at (4)
+             [-<[-]>
+               >>>>>>>>>>>>.  'T'
+               <<<-----.      'a'
+               ++++++++++.    'k'
+               ------.        'e'
+               >>>>.          ' '
+               <<<----.       'o'
+               -.             'n'
+               <.             'e'
+               >>>>.          ' '
+               <<<<-.         'd'
+               >+.            'o'
+               ++++++++.      'w'
+               ---------.     'n'
+               >>>.           ' '
+               <<<<---.       'a'
+               >.             'n'
+               <+++.          'd'
+               >>>>.          ' '
+               <<<++.         'p'
+               <---.          'a'
+               >+++..         'ss'
+               >>>.           ' '
+               <<<<++++++++.  'i'
+               >+.            't'
+               >>>.           ' '
+               <<<<--------.  'a'
+               >--.           'r'
+               ---.           'o'
+               ++++++.        'u'
+               -------.       'n'
+               <+++.          'd'
+               ++>+++++       reset (13) and (14) to 'f' and 's'
+               >>>>.          comma
+               <.             ' '
+
+               [<]<<<<<<< at (4)
+             ]+
+
+            >>>>>> at (10)
+            decrements values
+            -<<<+>>[<<[-]<+<+>>>>-]<<<<[>-<[-]]>[->>>+<<<]>[->->+++++++++<<]>>> at (10)
+
+         >>[>]>>>>] at (24)
+      <<<<] at (20)
+
+    >>>>>>]+ at (26)
+
+    <<<<<<<[<]< at (10)
+  ]
+  +<+
+  <<<<<<+< at (2)
+  -
+]
+
+print 'Go to the store and buy some more' comma ' '
+
+  >>>>>>>>>>[>]>>>>> at (25)
+  [->[-]<]+> at (26)
+  [-<[-]
+    <<<<<<<<< at (16)
+    -------------.   'G'
+    <<----.          'o'
+    >>>.             ' '
+    <<<+++++.        't'
+    -----.           'o'
+    >>>.             ' '
+    <<<+++++.        't'
+    <++.             'h'
+    ---.             'e'
+    >>>>.            ' '
+    <<<-.            's'
+    +.               't'
+    -----.           'o'
+    +++.             'r'
+    <.               'e'
+    >>>>.            ' '
+    <<<<----.        'a'
+    >----.           'n'
+    <+++.            'd'
+    >>>>.            ' '
+    <<<<--.          'b'
+    >+++++++.        'u'
+    ++++.            'y'
+    >>>.             ' '
+    <<<------.       's'
+    ----.            'o'
+    --.              'm'
+    <+++.            'e'
+    >>>>.            ' '
+    <<<.             'm'
+    ++.              'o'
+    +++.+            'r'
+    <.+              'e'
+    >>>>>.           coma
+    <.               ' '
+    >>>>>>>>>
+  ]+
+
+  Initialize last loop to print final '99 bottles of beer on the wall' DOT
+  <[-]+<[-]<[-]<[-]+<<< at (19)
+  [<]<[-]<[-]<[-]<[-] at (7)
+  ++++++++++[->+>+>++++++++++<<<]>->->-
+  <<<<<<[-]+<[-]<+<< at (0)
+]

assets/bf/hello

@@ -0,0 +1,2 @@
+>++++++++[-<+++++++++>]<.>>+>-[+]++>++>+++[>[->+++<<+++>]<<]>-----.>->
++++..+++.>-.<<+[>[+>+]>>]<--------------.>>.+++.------.--------.>+.>+.

assets/bf/scan

@@ -0,0 +1,21 @@
+Calculate the value 256 and test if it's zero
+If the interpreter errors on overflow this is where it'll happen
+++++++++[>++++++++<-]>[<++++>-]
++<[>-<
+    Not zero so multiply by 256 again to get 65536
+    [>++++<-]>[<++++++++>-]<[>++++++++<-]
+    +>[>
+        # Print "32"
+        ++++++++++[>+++++<-]>+.-.[-]<
+    <[-]<->] <[>>
+        # Print "16"
+        +++++++[>+++++++<-]>.+++++.[-]<
+<<-]] >[>
+    # Print "8"
+    ++++++++[>+++++++<-]>.[-]<
+<-]<
+# Print " bit cells\n"
++++++++++++[>+++>+++++++++>+++++++++>+<<<<-]>-.>-.+++++++.+++++++++++.<.
+>>.++.+++++++..<-.>>-
+Clean up used cells.
+[[-]<]

src/net/torvald/tsvm/firmware/Firmware.kt

@@ -11,9 +11,7 @@ import java.lang.RuntimeException
 
 internal class Firmware(val vm: VM) : TwoArgFunction() {
 
-    class ErrorIllegalAccess(val addr: Long) : RuntimeException() {
+    class ErrorIllegalAccess(val addr: Long) : RuntimeException("Segmentation fault at 0x${addr.toString(16).padStart(8, '0')}")
-
-    }
 
     companion object {
         internal fun translateAddr(vm : VM, addr: LuaValue): Pair<Any?, Long> {