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implement Line2rec, Gridmodule;
include "sys.m";
sys: Sys;
include "draw.m";
include "sh.m";
include "bufio.m";
bufio: Bufio;
Iobuf: import bufio;
include "alphabet/reports.m";
reports: Reports;
Report, report: import reports;
include "alphabet/endpoints.m";
include "alphabet/grid.m";
grid: Grid;
Value: import grid;
Line2rec: module {};
types(): string
{
return "bf";
}
init()
{
sys = load Sys Sys->PATH;
grid = load Grid Grid->PATH;
reports = load Reports Reports->PATH;
bufio = load Bufio Bufio->PATH;
}
quit()
{
}
run(nil: chan of string, r: ref Report,
nil: list of (int, list of ref Value), args: list of ref Value): ref Value
{
f := chan of ref Sys->FD;
spawn line2recproc((hd args).f().i, f, r.start("line2rec"));
return ref Value.Vb(f);
}
line2recproc(
f0,
f1: chan of ref Sys->FD,
errorc: chan of string)
{
(fd0, fd1) := startfilter(f0, f1, errorc);
iob0 := bufio->fopen(fd0, Sys->OREAD);
iob1 := bufio->fopen(fd1, Sys->OWRITE);
{
while((s := iob0.gets('\n')) != nil){
d := array of byte s;
if(iob1.puts("data "+string len d) < 0)
break;
if(iob1.write(d, len d) != len d)
break;
}
iob1.flush();
sys->fprint(fd1, "");
}exception{
"write on closed pipe" =>
;
}
reports->quit(errorc);
}
# read side (when it's an argument):
# read proposed new fd
# write actual fd for them to write to (creating pipe in necessary)
#
# write side (when you're returning it):
# write a proposed new fd (or nil if no suggestion)
# read actual fd for writing
startfilter(f0, f1: chan of ref Sys->FD, errorc: chan of string): (ref Sys->FD, ref Sys->FD)
{
f1 <-= nil;
if((fd1 := <-f1) == nil){
<-f0;
f0 <-= nil;
reports->quit(errorc);
}
if((fd0 := <-f0) == nil){
sys->pipe(p := array[2] of ref Sys->FD);
f0 <-= p[1];
fd0 = p[0];
}else
f0 <-= nil;
return (fd0, fd1);
}
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