(and-record trace [
  label:string-address
  contents:string-address
])
(address trace-address (trace))
(array trace-address-array (trace-address))
(address trace-address-array-address (trace-address-array))
(address trace-address-array-address-address (trace-address-array-address))

(and-record instruction-trace [
  call-stack:string-address-array-address
  pc:string-address  ; should be integer?
  instruction:string-address
  children:trace-address-array-address
])
(address instruction-trace-address (instruction-trace))
(array instruction-trace-address-array (instruction-trace-address))
(address instruction-trace-address-array-address (instruction-trace-address-array))

(function parse-traces [  ; stream-address -> instruction-trace-address-array-address
  (default-space:space-address <- new space:literal 30:literal)
;?   ($print (("parse-traces\n" literal))) ;? 2
  (in:stream-address <- next-input)
  ; check input size
  ($print (("counting lines\n" literal)))
  (n:integer <- copy 0:literal)
  { begin
    (done?:boolean <- end-of-stream? in:stream-address)
    (break-if done?:boolean)
;?     ($start-tracing) ;? 1
    (c:character <- read-character in:stream-address)
    { begin
      (newline?:boolean <- equal c:character ((#\newline literal)))
      (break-unless newline?:boolean)
      (n:integer <- add n:integer 1:literal)
      { begin
;?         (print?:boolean <- divides? n:integer 100:literal)
;?         (break-unless print?:boolean)
        ($print ((" " literal)))
        ($print n:integer)
        ($print (("\n" literal)))
      }
    }
;?     ($quit) ;? 1
    (loop)
  }
  ($print n:integer)
  ($print ((" lines\n" literal)))
  (in:stream-address <- rewind-stream in:stream-address)
  ; prepare result
  (result:buffer-address <- init-buffer 30:literal)
  (curr-tail:instruction-trace-address <- copy nil:literal)
  (ch:buffer-address <- init-buffer 5:literal)  ; accumulator for traces between instructions
  (run:string-address/const <- new "run")
  ($print (("parsing\n" literal)))
  (n:integer <- copy 0:literal)
  ; reading each line from 'in'
  { begin
    next-line
    (done?:boolean <- end-of-stream? in:stream-address)
;?     ($print done?:boolean) ;? 1
;?     ($print (("\n" literal))) ;? 1
    (break-if done?:boolean)
    ; parse next line as a generic trace
    (line:string-address <- read-line in:stream-address)
    { begin
      (n:integer <- add n:integer 1:literal)
      (print?:boolean <- divides? n:integer 100:literal)
      (break-unless print?:boolean)
      ($print ((" " literal)))
      ($print n:integer)
      ($print (("\n" literal)))
    }
;?     (print-string nil:literal/terminal line:string-address) ;? 1
    (f:trace-address <- parse-trace line:string-address)
    (l:string-address <- get f:trace-address/deref label:offset)
    { begin
      ; if it's an instruction trace with label 'run'
      (inst?:boolean <- string-equal l:string-address run:string-address/const)
      (break-unless inst?:boolean)
      ; add accumulated traces to curr-tail
      { begin
        (break-unless curr-tail:instruction-trace-address)
        (c:trace-address-array-address-address <- get-address curr-tail:instruction-trace-address/deref children:offset)
        (c:trace-address-array-address-address/deref <- to-array ch:buffer-address)
        ; clear 'ch'
        (ch:buffer-address <- init-buffer 5:literal)
      }
      ; append a new curr-tail to result
      (curr-tail:instruction-trace-address <- parse-instruction-trace f:trace-address)
      (result:buffer-address <- append result:buffer-address curr-tail:instruction-trace-address)
      (jump next-line:offset)  ; loop
    }
    ; otherwise accumulate trace
    (loop-unless curr-tail:instruction-trace-address)
    (ch:buffer-address <- append ch:buffer-address f:trace-address)
    (loop)
  }
  ; add accumulated traces to final curr-tail
  ; todo: test
  { begin
    (break-unless curr-tail:instruction-trace-address)
    (c:trace-address-array-address-address <- get-address curr-tail:instruction-trace-address/deref children:offset)
    (c:trace-address-array-address-address/deref <- to-array ch:buffer-address)
  }
  (s:instruction-trace-address-array-address <- to-array result:buffer-address)
  (reply s:instruction-trace-address-array-address)
])

(function parse-instruction-trace [  ; trace-address -> instruction-trace-address
  (default-space:space-address <- new space:literal 30:literal)
;?   ($print (("parse-instruction-trace\n" literal))) ;? 1
  (in:trace-address <- next-input)
  (buf:string-address <- get in:trace-address/deref contents:offset)
;?   (print-string nil:literal buf:string-address) ;? 1
;?   ($print (("\n" literal))) ;? 1
  (result:instruction-trace-address <- new instruction-trace:literal)
  (f1:string-address rest:string-address <- split-first buf:string-address ((#\space literal)))
;?   ($print (("call-stack: " literal))) ;? 1
;?   (print-string nil:literal f1:string-address) ;? 1
;?   ($print (("\n" literal))) ;? 1
  (cs:string-address-array-address-address <- get-address result:instruction-trace-address/deref call-stack:offset)
  (cs:string-address-array-address-address/deref <- split f1:string-address ((#\/ literal)))
  (p:string-address-address <- get-address result:instruction-trace-address/deref pc:offset)
  (delim:string-address <- new ": ")
  (p:string-address-address/deref rest:string-address <- split-first-at-substring rest:string-address delim:string-address)
  (inst:string-address-address <- get-address result:instruction-trace-address/deref instruction:offset)
  (inst:string-address-address/deref <- copy rest:string-address)
  (reply result:instruction-trace-address)
])

(function parse-trace [  ; string-address -> trace-address
  (default-space:space-address <- new space:literal 30:literal)
;?   ($print (("parse-trace\n" literal))) ;? 1
  (in:string-address <- next-input)
  (result:trace-address <- new trace:literal)
  (delim:string-address <- new ": ")
  (first:string-address rest:string-address <- split-first-at-substring in:string-address delim:string-address)
  (l:string-address-address <- get-address result:trace-address/deref label:offset)
  (l:string-address-address/deref <- copy first:string-address)
  (c:string-address-address <- get-address result:trace-address/deref contents:offset)
  (c:string-address-address/deref <- copy rest:string-address)
  (reply result:trace-address)
])

(function print-trace [
  (default-space:space-address <- new space:literal 30:literal)
  (screen:terminal-address <- next-input)
  (x:trace-address <- next-input)
  (l:string-address <- get x:trace-address/deref label:offset)
  (clear-line screen:terminal-address)
  (print-string screen:terminal-address l:string-address)
  (print-character screen:terminal-address ((#\space literal)))
  (print-character screen:terminal-address ((#\: literal)))
  (print-character screen:terminal-address ((#\space literal)))
  (c:string-address <- get x:trace-address/deref contents:offset)
  (print-string screen:terminal-address c:string-address)
])

(function print-instruction-trace-parent [
  (default-space:space-address <- new space:literal 30:literal)
  (screen:terminal-address <- next-input)
  (x:instruction-trace-address <- next-input)
  (0:space-address/names:browser-state <- next-input)
  (clear-line screen:terminal-address)
  (print-character screen:terminal-address ((#\- literal)))
  (print-character screen:terminal-address ((#\space literal)))
  ; print call stack
  (c:string-address-array-address <- get x:instruction-trace-address/deref call-stack:offset)
  (i:integer <- copy 0:literal)
  (len:integer <- length c:string-address-array-address/deref)
  { begin
    (done?:boolean <- greater-or-equal i:integer len:integer)
    (break-if done?:boolean)
    (s:string-address <- index c:string-address-array-address/deref i:integer)
    (print-string screen:terminal-address s:string-address)
    (print-character screen:terminal-address ((#\/ literal)))
    (i:integer <- add i:integer 1:literal)
    (loop)
  }
  ; print pc
  (print-character screen:terminal-address ((#\space literal)))
  (p:string-address <- get x:instruction-trace-address/deref pc:offset)
  (print-string screen:terminal-address p:string-address)
  ; print instruction
  (print-character screen:terminal-address ((#\space literal)))
  (print-character screen:terminal-address ((#\: literal)))
  (print-character screen:terminal-address ((#\space literal)))
  (i:string-address <- get x:instruction-trace-address/deref instruction:offset)
  (print-string screen:terminal-address i:string-address)
  (add-line 0:space-address/browser-state screen:terminal-address)
])

(function print-instruction-trace [
  (default-space:space-address <- new space:literal 30:literal)
  (screen:terminal-address <- next-input)
  (x:instruction-trace-address <- next-input)
  (0:space-address/names:browser-state <- next-input)
  (print-instruction-trace-parent screen:terminal-address x:instruction-trace-address 0:space-address/browser-state)
  ; print children
  (ch:trace-address-array-address <- get x:instruction-trace-address/deref children:offset)
  (i:integer <- copy 0:literal)
  { begin
    ; todo: test
    (break-if ch:trace-address-array-address)
    (reply)
  }
  (len:integer <- length ch:trace-address-array-address/deref)
  (expanded-children:integer/space:1 <- copy len:integer)
  { begin
;?     ($print (("i: " literal))) ;? 1
;?     ($print i:integer) ;? 1
;?     ($print (("\n" literal))) ;? 1
    ; until done with trace
    (done?:boolean <- greater-or-equal i:integer len:integer)
    (break-if done?:boolean)
    ; or screen ends
    (screen-done?:boolean <- greater-or-equal cursor-row:integer/space:1 screen-height:integer/space:1)
    (break-if screen-done?:boolean)
    (t:trace-address <- index ch:trace-address-array-address/deref i:integer)
    (print-character screen:terminal-address ((#\space literal)))
    (print-character screen:terminal-address ((#\space literal)))
    (print-character screen:terminal-address ((#\space literal)))
    (print-trace screen:terminal-address t:trace-address)
    (add-line 0:space-address/browser-state screen:terminal-address)
    (last-subindex-on-page:integer/space:1 <- copy i:integer)
;?     ($print (("subindex: " literal))) ;? 1
;?     ($print last-subindex-on-page:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    (i:integer <- add i:integer 1:literal)
    (loop)
  }
])

(function print-instruction-trace-collapsed [
  (default-space:space-address <- new space:literal 30:literal)
  (screen:terminal <- next-input)
  (x:instruction-trace-address <- next-input)
  (browser-state:space-address <- next-input)
  (clear-line screen:terminal-address)
  (print-character screen:terminal-address ((#\+ literal)))
  (print-character screen:terminal-address ((#\space literal)))
  ; print call stack
  (c:string-address-array-address <- get x:instruction-trace-address/deref call-stack:offset)
  (i:integer <- copy 0:literal)
  (len:integer <- length c:string-address-array-address/deref)
  { begin
    (done?:boolean <- greater-or-equal i:integer len:integer)
    (break-if done?:boolean)
    (s:string-address <- index c:string-address-array-address/deref i:integer)
    (print-string screen:terminal-address s:string-address)
;?     (print-character screen:terminal-address ((#\space literal)))
    (print-character screen:terminal-address ((#\/ literal)))
;?     (print-character screen:terminal-address ((#\space literal)))
    (i:integer <- add i:integer 1:literal)
    (loop)
  }
  ; print pc
  (print-character screen:terminal-address ((#\space literal)))
  (p:string-address <- get x:instruction-trace-address/deref pc:offset)
  (print-string screen:terminal-address p:string-address)
  ; print instruction
  (print-character screen:terminal-address ((#\space literal)))
  (print-character screen:terminal-address ((#\: literal)))
  (print-character screen:terminal-address ((#\space literal)))
  (i:string-address <- get x:instruction-trace-address/deref instruction:offset)
  (print-string screen:terminal-address i:string-address)
  (add-line browser-state:space-address screen:terminal-address)
])

(function instruction-trace-num-children [
  (default-space:space-address <- new space:literal 30:literal)
  (traces:instruction-trace-address-array-address <- next-input)
  (index:integer <- next-input)
  (tr:instruction-trace-address <- index traces:instruction-trace-address-array-address/deref index:integer)
  (tr-children:trace-address-array-address <- get tr:instruction-trace-address/deref children:offset)
  (n:integer <- length tr-children:instruction-trace-address-array-address/deref)
  (reply n:integer)
])

;; data structure
(function browser-state [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  ; trace state
  (traces:instruction-trace-address-array-address <- next-input)  ; the ground truth being rendered
  (expanded-index:integer <- copy -1:literal)  ; currently trace browser only ever shows one item expanded
  (expanded-children:integer <- copy -1:literal)
  (first-index-on-page:integer <- copy 0:literal)  ; 'outer' line with label 'run'
  (first-subindex-on-page:integer <- copy -2:literal)  ; 'inner' line with other labels; -2 or lower => not expanded; -1 => expanded and include parent; 0 => expanded and start at first child
  (last-index-on-page:integer <- copy 0:literal)
  (last-subindex-on-page:integer <- copy -2:literal)
  ; screen state
  (screen-height:integer <- next-input)  ; 'hardware' limitation
  (app-height:integer <- copy 0:literal)  ; area of the screen we're responsible for; can't be larger than screen-height
  (printed-height:integer <- copy 0:literal)  ; part of screen that currently has text; can't be larger than app-height
  (cursor-row:integer <- copy 0:literal)  ; position of cursor on screen; can't be larger than printed-height + 1
  (reply default-space:space-address)
])

(function $dump-browser-state [
  (default-space:space-address/names:browser-state <- next-input)
  ($print expanded-index:integer)
  ($print (("*" literal)))
  ($print expanded-children:integer)
  ($print ((": " literal)))
  ($print first-index-on-page:integer)
  ($print (("/" literal)))
  ($print first-subindex-on-page:integer)
  ($print ((" => " literal)))
  ($print last-index-on-page:integer)
  ($print (("/" literal)))
  ($print last-subindex-on-page:integer)
  ($print (("\n" literal)))
  ($print cursor-row:integer)
  ($print ((" " literal)))
  ($print printed-height:integer)
  ($print ((" " literal)))
  ($print app-height:integer)
  ($print ((" " literal)))
  ($print screen-height:integer)
  ($print (("\n" literal)))
])

(function down [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  ; if at expanded, skip past nested lines
  { begin
    (no-expanded?:boolean <- less-than expanded-index:integer/space:1 0:literal)
    (break-if no-expanded?:boolean)
    (at-expanded?:boolean <- equal cursor-row:integer/space:1 expanded-index:integer/space:1)
    (break-unless at-expanded?:boolean)
;?     ($print (("down: at expanded index\n" literal))) ;? 1
    (n:integer <- instruction-trace-num-children traces:instruction-trace-address-array-address/space:1 expanded-index:integer/space:1)
    (n:integer <- add n:integer 1:literal)
    (i:integer <- copy 0:literal)
    { begin
      (done?:boolean <- greater-or-equal i:integer n:integer)
      (break-if done?:boolean)
      (at-bottom?:boolean <- greater-or-equal cursor-row:integer/space:1 printed-height:integer/space:1)
      (break-if at-bottom?:boolean)
;?       ($print (("down: incrementing\n" literal))) ;? 1
      (cursor-row:integer/space:1 <- add cursor-row:integer/space:1 1:literal)
      (cursor-down screen:terminal-address)
      (i:integer <- add i:integer 1:literal)
      (loop)
    }
    (reply)
  }
  ; if not at bottom, move cursor down
  { begin
    (at-bottom?:boolean <- greater-or-equal cursor-row:integer/space:1 printed-height:integer/space:1)
    (break-if at-bottom?:boolean)
    (cursor-row:integer/space:1 <- add cursor-row:integer/space:1 1:literal)
    (cursor-down screen:terminal-address)
  }
])

(function up [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  ; if at expanded, skip past nested lines
  { begin
    (no-expanded?:boolean <- less-than expanded-index:integer/space:1 0:literal)
    (break-if no-expanded?:boolean)
    (n:integer <- instruction-trace-num-children traces:instruction-trace-address-array-address/space:1 expanded-index:integer/space:1)
    (n:integer <- add n:integer 1:literal)
    (cursor-row-below-expanded:integer <- add expanded-index:integer/space:1 n:integer)
    (just-below-expanded?:boolean <- equal cursor-row:integer/space:1 cursor-row-below-expanded:integer)
    (break-unless just-below-expanded?:boolean)
    (i:integer <- copy 0:literal)
    { begin
      (done?:boolean <- greater-or-equal i:integer n:integer)
      (break-if done?:boolean)
      (at-top?:boolean <- lesser-or-equal cursor-row:integer/space:1 0:literal)
      (break-if at-top?:boolean)
      (cursor-row:integer/space:1 <- subtract cursor-row:integer/space:1 1:literal)
      (cursor-up screen:terminal-address)
      (i:integer <- add i:integer 1:literal)
      (loop)
    }
    (reply)
  }
  ; if not at top, move cursor up
  { begin
    (at-top?:boolean <- lesser-or-equal cursor-row:integer/space:1 0:literal)
    (break-if at-top?:boolean)
    (cursor-row:integer/space:1 <- subtract cursor-row:integer/space:1 1:literal)
    (cursor-up screen:terminal-address)
  }
])

(function to-bottom [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  { begin
    (at-bottom?:boolean <- greater-or-equal cursor-row:integer/space:1 printed-height:integer/space:1)
    (break-if at-bottom?:boolean)
    (down 0:space-address screen:terminal-address)
    (loop)
  }
])

(function to-top [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  { begin
    (at-top?:boolean <- lesser-or-equal cursor-row:integer/space:1 0:literal)
    (break-if at-top?:boolean)
    (up 0:space-address screen:terminal-address)
    (loop)
  }
])

(function back-to [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  (target-row:integer <- next-input)
;?   ($print (("before back-to: " literal))) ;? 1
;?   ($print cursor-row:integer/space:1) ;? 1
;?   ($print (("\n" literal))) ;? 1
  { begin
    (below-target?:boolean <- greater-than cursor-row:integer/space:1 target-row:integer)
    (break-unless below-target?:boolean)
;?     ($print (("below target\n" literal))) ;? 1
    (up 0:space-address screen:terminal-address)
    (loop)
  }
  { begin
    (above-target?:boolean <- less-than cursor-row:integer/space:1 target-row:integer)
    (break-unless above-target?:boolean)
;?     ($print (("above target\n" literal))) ;? 1
    (down 0:space-address screen:terminal-address)
    (loop)
  }
;?   ($print (("after back-to: " literal))) ;? 1
;?   ($print cursor-row:integer/space:1) ;? 1
;?   ($print (("\n" literal))) ;? 1
])

(function add-line [  ; move down, adding line if necessary
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  { begin
    (at-bottom?:boolean <- greater-or-equal cursor-row:integer/space:1 printed-height:integer/space:1)
    (break-unless at-bottom?:boolean)
    { begin
      (screen-full?:boolean <- greater-or-equal app-height:integer/space:1 screen-height:integer/space:1)
      (break-unless screen-full?:boolean)
      (cursor-to-next-line screen:terminal-address)
      (cursor-up screen:terminal-address)
      (reply)
    }
    (printed-height:integer/space:1 <- add printed-height:integer/space:1 1:literal)
    ; update app-height if necessary
    { begin
      (grow-max?:boolean <- greater-than printed-height:integer/space:1 app-height:integer/space:1)
      (break-unless grow-max?:boolean)
      (app-height:integer/space:1 <- copy printed-height:integer/space:1)
    }
  }
  (cursor-row:integer/space:1 <- add cursor-row:integer/space:1 1:literal)
  (cursor-to-next-line screen:terminal-address)
])

;; initial screen state
(function print-traces-collapsed [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
;?   ($print (("print traces collapsed\n" literal))) ;? 1
  (print-traces-collapsed-from 0:space-address/browser-state screen:terminal-address 0:literal/from)
  (clear-rest-of-page 0:space-address/browser-state screen:terminal-address)
])

(function print-traces-collapsed-from [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  (trace-index:integer <- next-input)
  (limit-index:integer <- next-input)  ; print until this index (exclusive)
  ; compute bound
  (max:integer <- length traces:instruction-trace-address-array-address/space:1/deref)
  { begin
    (break-unless limit-index:integer)
    (max:integer <- min max:integer limit-index:integer)
  }
  ; print remaining traces collapsed
  { begin
    ; until trace ends
    (trace-done?:boolean <- greater-or-equal trace-index:integer max:integer)
    (break-if trace-done?:boolean)
    ; or screen ends
    (screen-done?:boolean <- greater-or-equal cursor-row:integer/space:1 screen-height:integer/space:1)
    (break-if screen-done?:boolean)
;?     ($print (("screen not done\n" literal))) ;? 1
    ; continue printing trace lines
    (tr:instruction-trace-address <- index traces:instruction-trace-address-array-address/space:1/deref trace-index:integer)
    (last-index-on-page:integer/space:1 <- copy trace-index:integer)
;?     ($print (("setting last index: " literal))) ;? 1
;?     ($print last-index-on-page:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    (last-subindex-on-page:integer/space:1 <- copy -2:literal)
    (print-instruction-trace-collapsed screen:terminal-address tr:instruction-trace-address 0:space-address/browser-state)
    (trace-index:integer <- add trace-index:integer 1:literal)
    (loop)
  }
])

(function clear-rest-of-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  { begin
    (done?:boolean <- greater-or-equal cursor-row:integer/space:1 app-height:integer/space:1)
    (break-if done?:boolean)
    (clear-line screen:terminal-address)
    (down 0:space-address/browser-state screen:terminal-address)
    (loop)
  }
])

(function print-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
;?   ($dump-browser-state 0:space-address/browser-state) ;? 3
  ; if top inside expanded index, complete existing trace
  (first-full-index:integer <- copy first-index-on-page:integer/space:1)
  { begin
    (screen-done?:boolean <- greater-or-equal cursor-row:integer/space:1 screen-height:integer/space:1)
    (break-unless screen-done?:boolean)
    (reply)
  }
;?   ($print (("\nAAA\n" literal))) ;? 4
  { begin
    (partial-trace?:boolean <- equal first-index-on-page:integer/space:1 expanded-index:integer/space:1)
    (break-unless partial-trace?:boolean)
;?   ($print (("AAA: partial\n" literal))) ;? 4
    (first-full-index:integer <- add first-full-index:integer 1<style>pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
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.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */</style><div class="highlight"><pre><span></span>dwm - dynamic window manager
============================
dwm is an extremely fast, small, and dynamic window manager for X.


Requirements
------------
In order to build dwm you need the Xlib header files.


Installation
------------
Edit config.mk to match your local setup (dwm is installed into
the /usr/local namespace by default).

Afterwards enter the following command to build and install dwm (if
necessary as root):

    make clean install

If you are going to use the default bluegray color scheme it is highly
recommended to also install the bluegray files shipped in the dextra package.


Running dwm
-----------
Add the following line to your .xinitrc to start dwm using startx:

    exec dwm

In order to connect dwm to a specific display, make sure that
the DISPLAY environment variable is set correctly, e.g.:

    DISPLAY=foo.bar:1 exec dwm

(This will start dwm on display :1 of the host foo.bar.)

In order to display status info in the bar, you can do something
like this in your .xinitrc:

    while true
    do
        xsetroot -name &quot;`date` `uptime | sed &#39;s/.*,//&#39;`&quot;
        sleep 1
    done &amp;
    exec dwm


Configuration
-------------
The configuration of dwm is done by creating a custom config.h
and (re)compiling the source code.
</pre></div>
y result:integer/index)
])

(function back-to-index [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (screen:terminal-address <- next-input)
  (target-index:integer <- next-input)
;?   ($print (("back-to-index: target " literal))) ;? 3
;?   ($print target-index:integer) ;? 3
;?   ($print (("\n" literal))) ;? 3
;?   ($print (("back-to-index: first subindex " literal))) ;? 1
;?   ($print first-subindex-on-page:integer/space:1) ;? 1
;?   ($print (("\n" literal))) ;? 1
  ; scan up until top, or *before* target-index (to skip expanded children)
  { begin
;?     ($print cursor-row:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    (at-top?:boolean <- equal cursor-row:integer/space:1 0:literal)
    (break-if at-top?:boolean)
    (index:integer <- cursor-row-to-trace-index 0:space-address/browser-state cursor-row:integer/space:1)
;?     ($print cursor-row:integer/space:1) ;? 3
;?     ($print ((" " literal))) ;? 3
;?     ($print index:integer) ;? 3
;?     ($print (("\n" literal))) ;? 3
    (done?:boolean <- less-than index:integer target-index:integer)
    (break-if done?:boolean)
    (up 0:space-address screen:terminal-address)
    (loop)
  }
  ; now if we're before target-index, down 1
;?   ($print (("final down?\n" literal))) ;? 1
  (index:integer <- cursor-row-to-trace-index 0:space-address/browser-state cursor-row:integer/space:1)
;?   ($print (("done scanning; cursor at row " literal))) ;? 2
;?   ($print cursor-row:integer/space:1) ;? 2
;?   ($print ((", which is index " literal))) ;? 2
;?   ($print index:integer) ;? 2
;?   ($print (("\n" literal))) ;? 2
  { begin
    (at-target?:boolean <- greater-or-equal index:integer target-index:integer)
    (break-if at-target?:boolean)
;?     ($print (("down 1\n" literal))) ;? 2
    ; above expanded
    (down 0:space-address screen:terminal-address)
  }
])

;; pagination helpers
(function at-first-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)  ; read-only
  (result:boolean <- lesser-or-equal first-index-on-page:integer/space:1 0:literal)
  { begin
    (break-if result:boolean)
    (reply nil:literal)
  }
  (expanded?:boolean <- equal expanded-index:integer/space:1 0:literal)
  { begin
    (break-if expanded?:boolean)
    (reply t:literal)
  }
  ; if first subindex is 0, the top-level line is on a previous page
  (result:boolean <- less-than first-subindex-on-page:integer/space:1 0:literal)
  (reply result:boolean)
])

(function at-final-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)  ; read-only
  (len:integer <- length traces:instruction-trace-address-array-address/space:1/deref)
  (final-index:integer <- subtract len:integer 1:literal)
  (result:boolean <- greater-or-equal last-index-on-page:integer/space:1 final-index:integer)
  { begin
    (break-if result:boolean)
    (reply nil:literal)
  }
  (last-trace-expanded?:boolean <- equal expanded-index:integer/space:1 len:integer)
  { begin
    (break-if last-trace-expanded?:boolean)
    (reply t:literal)
  }
  (result:boolean <- greater-or-equal last-subindex-on-page:integer/space:1 expanded-children:integer/space:1)
  (reply result:boolean)
])

(function next-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  { begin
;?     ($print (("expanded: " literal))) ;? 3
;?     ($print expanded-index:integer/space:1) ;? 3
;?     ($print ((" last index: " literal))) ;? 3
;?     ($print last-index-on-page:integer/space:1) ;? 3
;?     ($print (("\n" literal))) ;? 3
    (last-index-expanded?:boolean <- equal expanded-index:integer/space:1 last-index-on-page:integer/space:1)
    (break-unless last-index-expanded?:boolean)
    ; expanded
;?     ($print (("last expanded\n" literal))) ;? 3
    { begin
      (expanded-index-done?:boolean <- equal expanded-children:integer/space:1 last-subindex-on-page:integer/space:1)
      (break-if expanded-index-done?:boolean 2:blocks)
;?       ($print (("children left\n" literal))) ;? 3
      ; children left to open
      (first-index-on-page:integer/space:1 <- copy last-index-on-page:integer/space:1)
      (first-subindex-on-page:integer/space:1 <- add last-subindex-on-page:integer/space:1 1:literal)
      (reply)
    }
  }
  (first-index-on-page:integer/space:1 <- add last-index-on-page:integer/space:1 1:literal)
  (first-subindex-on-page:integer/space:1 <- copy -2:literal)
])

(function previous-page [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
;?   ($print (("before: " literal))) ;? 2
;?   ($print first-index-on-page:integer/space:1) ;? 2
;?   ($print ((" " literal))) ;? 2
;?   ($print first-subindex-on-page:integer/space:1) ;? 2
;?   ($print (("\n" literal))) ;? 2
  ; easy case: no expanded-index
  (jump-unless expanded-index:integer/space:1)
;?   ($print (("b\n" literal))) ;? 4
  (x:boolean <- less-than expanded-index:integer/space:1 0:literal)
  (jump-if x:boolean easy-case:offset)
  ; easy case: expanded-index lies below top of current page
;?   ($print (("c\n" literal))) ;? 4
  (x:boolean <- greater-than expanded-index:integer/space:1 first-index-on-page:integer/space:1)
  (jump-if x:boolean easy-case:offset)
  ; easy case: expanded-index *starts* at top of current page
;?   ($print (("d\n" literal))) ;? 5
  (top-of-screen-inside-expanded:boolean <- equal expanded-index:integer/space:1 first-index-on-page:integer/space:1)
  (y:boolean <- lesser-or-equal first-subindex-on-page:integer/space:1 -1:literal)
  (y:boolean <- and top-of-screen-inside-expanded:boolean y:boolean)
  (jump-if y:boolean easy-case:offset)
  ; easy case: expanded-index too far up for previous page
;?   ($print (("e\n" literal))) ;? 5
  (delta-to-expanded:integer <- subtract first-index-on-page:integer/space:1 expanded-index:integer/space:1)
;?   ($print delta-to-expanded:integer) ;? 1
;?   ($print (("\n" literal))) ;? 1
  (x:boolean <- greater-than delta-to-expanded:integer screen-height:integer/space:1)
  (jump-if x:boolean easy-case:offset)
;?   ($print (("f\n" literal))) ;? 5
  ; tough case: expanded index overlaps current and/or previous page
  (lines-remaining-to-decrement:integer <- copy screen-height:integer/space:1)
  ; a) scroll to just below expanded-index if necessary
  (below-expanded-index:integer <- add expanded-index:integer/space:1 1:literal)
  { begin
    (done?:boolean <- done-scrolling-up default-space:space-address)
    (break-if done?:boolean)
    (done?:boolean <- lesser-or-equal first-index-on-page:integer/space:1 below-expanded-index:integer)
    (break-if done?:boolean)
;?     ($print (("g\n" literal))) ;? 2
    (first-index-on-page:integer/space:1 <- subtract first-index-on-page:integer/space:1 1:literal)
    (lines-remaining-to-decrement:integer <- subtract lines-remaining-to-decrement:integer 1:literal)
    (loop)
  }
  { begin
;?     ($print (("h\n" literal))) ;? 2
    (x:boolean <- equal first-index-on-page:integer/space:1 below-expanded-index:integer)
    (break-unless x:boolean)
    (first-index-on-page:integer/space:1 <- copy expanded-index:integer/space:1)
    (first-subindex-on-page:integer/space:1 <- subtract expanded-children:integer/space:1 1:literal)
    (lines-remaining-to-decrement:integer <- subtract lines-remaining-to-decrement:integer 1:literal)
  }
  ; b) scroll through expanded-children if necessary
  { begin
    (done?:boolean <- done-scrolling-up default-space:space-address)
    (break-if done?:boolean)
    (done?:boolean <- less-than first-subindex-on-page:integer/space:1 0:literal)
    (break-if done?:boolean)
;?     ($print (("i\n" literal))) ;? 2
    (first-subindex-on-page:integer/space:1 <- subtract first-subindex-on-page:integer/space:1 1:literal)
    (lines-remaining-to-decrement:integer <- subtract lines-remaining-to-decrement:integer 1:literal)
    (loop)
  }
  ; c) jump past expanded-index parent if necessary
;?   ($print (("j\n" literal))) ;? 2
  { begin
    (done?:boolean <- done-scrolling-up default-space:space-address)
    (break-if done?:boolean)
;?     ($print (("k\n" literal))) ;? 2
    (first-index-on-page:integer/space:1 <- subtract first-index-on-page:integer/space:1 1:literal)
    (first-subindex-on-page:integer/space:1 <- copy -2:literal)
    (lines-remaining-to-decrement:integer <- subtract lines-remaining-to-decrement:integer 1:literal)
  }
  ; d) scroll up before expanded-index if necessary
;?   ($print (("l\n" literal))) ;? 2
  { begin
    (done?:boolean <- done-scrolling-up default-space:space-address)
    (break-if done?:boolean)
;?     ($print (("m\n" literal))) ;? 2
    (first-index-on-page:integer/space:1 <- subtract first-index-on-page:integer/space:1 1:literal)
    (lines-remaining-to-decrement:integer <- subtract lines-remaining-to-decrement:integer 1:literal)
    (loop)
  }
  (reply)
  easy-case
  (first-index-on-page:integer/space:1 <- subtract first-index-on-page:integer/space:1 screen-height:integer/space:1)
  (first-index-on-page:integer/space:1 <- max first-index-on-page:integer/space:1 0:literal)
  (first-subindex-on-page:integer/space:1 <- copy -2:literal)
])

(function done-scrolling-up [
  (default-space:space-address/names:previous-page <- next-input)
  (0:space-address/names:browser-state <- copy 0:space-address)  ; just to wire up names for space/1
  (at-top-of-screen?:boolean <- lesser-or-equal lines-remaining-to-decrement:integer 0:literal)
  (jump-if at-top-of-screen?:boolean done:offset)
  (at-first-index:boolean <- lesser-or-equal first-index-on-page:integer/space:1 0:literal)
  (at-first-subindex:boolean <- lesser-or-equal first-subindex-on-page:integer/space:1 -1:literal)
  (trace-done?:boolean <- and at-first-index:boolean at-first-subindex:boolean)
  (jump-if trace-done?:boolean done:offset)
  (reply nil:literal)
  done
  (reply t:literal)
])

;; modify screen state in response to a single key
(function process-key [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  (0:space-address/names:browser-state <- next-input)
  (k:keyboard-address <- next-input)
  (screen:terminal-address <- next-input)
  (c:character <- read-key k:keyboard-address silent:literal/terminal)
  { begin
    ; no key yet
    (break-if c:character)
    (reply nil:literal)
  }
;?   ($print (("key pressed: " literal))) ;? 1
;?   ($write c:character) ;? 1
;?   ($print (("\n" literal))) ;? 1
  { begin
    ; user quit
    (q-pressed?:boolean <- equal c:character ((#\q literal)))
    (end-of-fake-keyboard-input?:boolean <- equal c:character ((#\null literal)))
    (quit?:boolean <- or q-pressed?:boolean end-of-fake-keyboard-input?:boolean)
    (break-unless quit?:boolean)
    (reply t:literal)
  }
  ; up/down navigation
  { begin
    (up?:boolean <- equal c:character ((up literal)))
    (k?:boolean <- equal c:character ((#\k literal)))
    (up?:boolean <- or up?:boolean k?:boolean)
    (break-unless up?:boolean)
    (up 0:space-address/browser-state screen:terminal-address)
    (reply nil:literal)
  }
  { begin
    (down?:boolean <- equal c:character ((down literal)))
    (j?:boolean <- equal c:character ((#\j literal)))
    (down?:boolean <- or down?:boolean j?:boolean)
    (break-unless down?:boolean)
    (down 0:space-address/browser-state screen:terminal-address)
    (reply nil:literal)
  }
  ; page up/page down
  { begin
    ; if page-up pressed
    (page-up?:boolean <- equal c:character ((pgup literal)))
    (K?:boolean <- equal c:character ((#\K literal)))
    (page-up?:boolean <- or page-up?:boolean K?:boolean)
    (break-unless page-up?:boolean)
    ; if we're not already at start of trace
    (first-page?:boolean <- at-first-page 0:space-address/browser-state)
    (break-if first-page?:boolean)
    ; move cursor to top of screen
    (to-top 0:space-address/browser-state screen:terminal-address)
    ; switch browser state
    (previous-page 0:space-address/browser-state)
;?     ($dump-browser-state 0:space-address) ;? 3
    ; redraw
    (print-page 0:space-address/browser-state screen:terminal-address)
    (reply nil:literal)
  }
  { begin
    ; if page-down pressed
    (page-down?:boolean <- equal c:character ((pgdn literal)))
    (J?:boolean <- equal c:character ((#\J literal)))
    (page-down?:boolean <- or page-down?:boolean J?:boolean)
    (break-unless page-down?:boolean)
    ; if we're not already at end of trace
    (final-page?:boolean <- at-final-page 0:space-address/browser-state)
    (break-if final-page?:boolean)
    ; move cursor to top of screen
    (to-top 0:space-address/browser-state screen:terminal-address)
;?     ($print (("before: " literal))) ;? 1
;?     ($print first-index-on-page:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    ; switch browser state
    (next-page 0:space-address/browser-state)
;?     ($print (("after: " literal))) ;? 1
;?     ($print first-index-on-page:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    ; redraw
    (print-page 0:space-address/browser-state screen:terminal-address)
    ; move cursor back to top of screen
    (to-top 0:space-address/browser-state screen:terminal-address)
    (reply nil:literal)
  }
  ; enter: expand/collapse current row
  { begin
    (toggle?:boolean <- equal c:character ((#\newline literal)))
    (break-unless toggle?:boolean)
;?     ($print (("expand: first subindex " literal))) ;? 1
;?     ($print first-subindex-on-page:integer/space:1) ;? 1
;?     ($print (("\n" literal))) ;? 1
    (original-cursor-row:integer <- copy cursor-row:integer/space:1)
;?     ($print (("cursor starts at row " literal))) ;? 6
;?     ($print original-cursor-row:integer) ;? 7
;?     ($print (("\n" literal))) ;? 7
    (original-trace-index:integer <- cursor-row-to-trace-index 0:space-address/browser-state original-cursor-row:integer)
;?     ($print (("which maps to index " literal))) ;? 7
;?     ($print original-trace-index:integer) ;? 9
;?     ($print (("\n" literal))) ;? 9
    ; is expanded-index already set?
    { begin
      (expanded?:boolean <- greater-or-equal expanded-index:integer/space:1 0:literal)
      (break-unless expanded?:boolean)
      (too-early?:boolean <- less-than expanded-index:integer/space:1 first-index-on-page:integer/space:1)
      (break-if too-early?:boolean)
      (too-late?:boolean <- greater-than expanded-index:integer/space:1 last-index-on-page:integer/space:1)
      (break-if too-late?:boolean)
      ; expanded-index is now on this page
;?       ($print (("expanded index on this page\n" literal))) ;? 6
      { begin
        ; are we at the expanded row?
        (at-expanded?:boolean <- equal original-trace-index:integer expanded-index:integer/space:1)
        (break-unless at-expanded?:boolean)
;?         ($print (("at expanded index\n" literal))) ;? 5
        ; print remaining lines collapsed and return
        (back-to-index 0:space-address/browser-state screen:terminal-address expanded-index:integer/space:1)
        (expanded-index:integer/space:1 <- copy -1:literal)
        (expanded-children:integer/space:1 <- copy -1:literal)
        (print-traces-collapsed-from 0:space-address/browser-state screen:terminal-address original-trace-index:integer)
        (clear-rest-of-page 0:space-address/browser-state screen:terminal-address)
        (back-to 0:space-address/browser-state screen:terminal-address original-cursor-row:integer)
        (reply nil:literal)
      }
      ; are we below the expanded row?
      { begin
        (below-expanded?:boolean <- greater-than original-trace-index:integer expanded-index:integer/space:1)
        (break-unless below-expanded?:boolean)
;?         ($print (("below expanded index\n" literal))) ;? 6
        (back-to-index 0:space-address/browser-state screen:terminal-address expanded-index:integer/space:1)
;?         ($print (("scanning up to row " literal))) ;? 3
;?         ($print cursor-row:integer/space:1) ;? 3
;?         ($print (("\n" literal))) ;? 3
        ; print traces collapsed until just before original row
        (print-traces-collapsed-from 0:space-address/browser-state screen:terminal-address expanded-index:integer/space:1 original-trace-index:integer/until)
        ; fall through
      }
    }
    ; expand original row and print traces below it
;?     ($print (("done collapsing previously expanded index\n" literal))) ;? 6
    (expanded-index:integer/space:1 <- copy original-trace-index:integer)
    (last-index-on-page:integer/space:1 <- copy original-trace-index:integer)
    (tr:instruction-trace-address <- index traces:instruction-trace-address-array-address/space:1/deref original-trace-index:integer)
;?     ($print (("expanded\n" literal))) ;? 6
    (print-instruction-trace screen:terminal-address tr:instruction-trace-address 0:space-address/browser-state)
    (next-index:integer <- add original-trace-index:integer 1:literal)
;?     ($print (("printing collapsed lines from " literal))) ;? 7
;?     ($print next-index:integer) ;? 8
;?     ($print (("\n" literal))) ;? 8
    (print-traces-collapsed-from 0:space-address/browser-state screen:terminal-address next-index:integer)
;?     ($print (("clearing rest of page\n" literal))) ;? 6
    (clear-rest-of-page 0:space-address/browser-state screen:terminal-address)
;?     ($print (("moving cursor back up\n" literal))) ;? 6
    (back-to-index 0:space-address/browser-state screen:terminal-address original-trace-index:integer)
;?     ($print (("returning\n" literal))) ;? 5
    (reply nil:literal)
  }
  (reply nil:literal)
])

(function browse-trace [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  ($print (("parsing trace... (might take a while, depending on how long the trace is)\n" literal)))
  (x:string-address <- next-input)
  (screen-height:integer <- next-input)
;?   (print-string nil:literal/terminal x:string-address) ;? 1
  (s:stream-address <- init-stream x:string-address)
  (traces:instruction-trace-address-array-address <- parse-traces s:stream-address)
  (0:space-address/names:browser-state <- browser-state traces:instruction-trace-address-array-address screen-height:integer)
  (cursor-mode)
  (print-traces-collapsed 0:space-address/browser-state nil:literal/terminal)
  { begin
    (quit?:boolean <- process-key 0:space-address/browser-state nil:literal/keyboard nil:literal/terminal)
    (break-if quit?:boolean)
    (loop)
  }
  ; move cursor to bottom before exiting
  (to-bottom 0:space-address/browser-state nil:literal/terminal)
  (retro-mode)
])

(function main [
  (default-space:space-address <- new space:literal 30:literal/capacity)
  ($print (("loading trace.. (takes ~10s)\n" literal)))
  (x:string-address <- new
"run: main 0: a b c
mem: 0
run: main 1: d e f
mem: 1
mem: 1
mem: 1
mem: 1
mem: 1
run: main 2: g hi
run: main 3: j
mem: 3
run: main 4: k
run: main 5: l
run: main 6: m
run: main 7: n
run: main 8: o")
  (browse-trace x:string-address 3:literal/screen-height)
])