diff options
| -rw-r--r-- | 072channel.mu | 78 |
1 files changed, 39 insertions, 39 deletions
diff --git a/072channel.mu b/072channel.mu index c6a40ef7..e1d6f805 100644 --- a/072channel.mu +++ b/072channel.mu @@ -194,45 +194,6 @@ scenario channel-wrap [ ] ] -## helpers - -# An empty channel has first-empty and first-full both at the same value. -def channel-empty? chan:address:channel:_elem -> result:boolean [ - local-scope - load-ingredients - # return chan.first-full == chan.first-free - full:number <- get *chan, first-full:offset - free:number <- get *chan, first-free:offset - result <- equal full, free -] - -# A full channel has first-empty just before first-full, wasting one slot. -# (Other alternatives: https://en.wikipedia.org/wiki/Circular_buffer#Full_.2F_Empty_Buffer_Distinction) -def channel-full? chan:address:channel:_elem -> result:boolean [ - local-scope - load-ingredients - # tmp = chan.first-free + 1 - tmp:number <- get *chan, first-free:offset - tmp <- add tmp, 1 - { - # if tmp == chan.capacity, tmp = 0 - len:number <- capacity chan - at-end?:boolean <- greater-or-equal tmp, len - break-unless at-end? - tmp <- copy 0 - } - # return chan.first-full == tmp - full:number <- get *chan, first-full:offset - result <- equal full, tmp -] - -def capacity chan:address:channel:_elem -> result:number [ - local-scope - load-ingredients - q:address:array:_elem <- get *chan, data:offset - result <- length *q -] - scenario channel-new-empty-not-full [ run [ 1:address:source:number, 2:address:sink:number <- new-channel 3/capacity @@ -289,6 +250,45 @@ scenario channel-read-not-full [ ] ] +## helpers + +# An empty channel has first-empty and first-full both at the same value. +def channel-empty? chan:address:channel:_elem -> result:boolean [ + local-scope + load-ingredients + # return chan.first-full == chan.first-free + full:number <- get *chan, first-full:offset + free:number <- get *chan, first-free:offset + result <- equal full, free +] + +# A full channel has first-empty just before first-full, wasting one slot. +# (Other alternatives: https://en.wikipedia.org/wiki/Circular_buffer#Full_.2F_Empty_Buffer_Distinction) +def channel-full? chan:address:channel:_elem -> result:boolean [ + local-scope + load-ingredients + # tmp = chan.first-free + 1 + tmp:number <- get *chan, first-free:offset + tmp <- add tmp, 1 + { + # if tmp == chan.capacity, tmp = 0 + len:number <- capacity chan + at-end?:boolean <- greater-or-equal tmp, len + break-unless at-end? + tmp <- copy 0 + } + # return chan.first-full == tmp + full:number <- get *chan, first-full:offset + result <- equal full, tmp +] + +def capacity chan:address:channel:_elem -> result:number [ + local-scope + load-ingredients + q:address:array:_elem <- get *chan, data:offset + result <- length *q +] + # helper for channels of characters in particular def buffer-lines in:address:source:character, buffered-out:address:sink:character -> buffered-out:address:sink:character, in:address:source:character [ local-scope |