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{ %TIMEOUT=105 }
{$mode objfpc}{$h+}
uses
{$ifdef UNIX}
cthreads,
{$endif}
sysutils,
classes;
const
fifolength = 1024;
type
tpair = class;
tproducethread = class(tthread)
pair: tpair;
constructor create(apair: tpair);
procedure execute; override;
end;
tconsumethread = class(tthread)
pair: tpair;
constructor create(apair: tpair);
procedure execute; override;
end;
tpair = class(tobject)
public
readindex: integer;
writeindex: integer;
fifo: array[0..fifolength-1] of pointer;
shared: pointer;
freefifolock: trtlcriticalsection;
produce_thread: tproducethread;
consume_thread: tconsumethread;
constructor create;
destructor destroy; override;
procedure resume;
procedure waitfor;
end;
var
done: boolean;
constructor tproducethread.create(apair: tpair);
begin
pair := apair;
inherited create(false);
end;
constructor tconsumethread.create(apair: tpair);
begin
pair := apair;
inherited create(false);
end;
constructor tpair.create;
begin
filldword(fifo, sizeof(fifo) div sizeof(dword), 0);
readindex := 0;
writeindex := 0;
initcriticalsection(freefifolock);
produce_thread := tproducethread.create(self);
consume_thread := tconsumethread.create(self);
end;
destructor tpair.destroy;
begin
produce_thread.free;
consume_thread.free;
donecriticalsection(freefifolock);
end;
procedure tpair.resume;
begin
produce_thread.resume;
consume_thread.resume;
end;
procedure tpair.waitfor;
begin
produce_thread.waitfor;
consume_thread.waitfor;
end;
type
ttestarray = array[0..31] of pointer;
procedure exercise_heap(var p: ttestarray; var i, j: integer);
begin
if p[i] = nil then
p[i] := getmem(((j*11) mod 532)+8)
else begin
freemem(p[i]);
p[i] := nil;
end;
inc(i);
if i >= 32 then
dec(i, 32);
inc(j, 13);
if j >= 256 then
dec(j, 256);
end;
procedure freearray(p: ppointer; count: integer);
var
i: integer;
begin
for i := 0 to count-1 do
begin
freemem(p[i]);
p[i] := nil;
end;
end;
procedure producer(pair: tpair);
var
p: ttestarray;
i, j, k: longint;
begin
done := false;
filldword(p, sizeof(p) div sizeof(dword), 0);
i := 0;
j := 0;
k := 0;
while not done do
begin
if ((pair.writeindex+1) mod fifolength) <> pair.readindex then
begin
freemem(pair.fifo[pair.writeindex]);
pair.fifo[pair.writeindex] := getmem(((pair.writeindex*17) mod 520)+8);
writebarrier;
pair.writeindex := (pair.writeindex + 1) mod 1024;
end else begin
exercise_heap(p,i,j);
inc(k);
if k = 100 then
begin
k := 0;
ThreadSwitch;
end;
end;
end;
freearray(p, sizeof(p) div sizeof(pointer));
entercriticalsection(pair.freefifolock);
sleep(200);
freearray(pair.fifo, sizeof(pair.fifo) div sizeof(pointer));
freemem(pair.shared);
leavecriticalsection(pair.freefifolock);
end;
procedure consumer(pair: tpair);
var
p: ttestarray;
i, j, k: longint;
begin
done := false;
filldword(p, sizeof(p) div sizeof(dword), 0);
i := 0;
j := 0;
k := 0;
entercriticalsection(pair.freefifolock);
while not done do
begin
if pair.readindex <> pair.writeindex then
begin
freemem(pair.fifo[pair.readindex]);
pair.fifo[pair.readindex] := getmem(((pair.writeindex*17) mod 520)+8);
writebarrier;
pair.readindex := (pair.readindex + 1) mod fifolength;
end else begin
exercise_heap(p,i,j);
inc(k);
if k = 100 then
begin
k := 0;
ThreadSwitch;
end;
end;
end;
pair.shared := getmem(12);
leavecriticalsection(pair.freefifolock);
freearray(p, sizeof(p) div sizeof(pointer));
end;
procedure tproducethread.execute;
begin
producer(pair);
end;
procedure tconsumethread.execute;
begin
consumer(pair);
end;
const
numpairs = 2;
var
pairs: array[1..numpairs] of tpair;
i, iter, num_iterations: integer;
begin
num_iterations := 20;
if paramcount > 0 then
num_iterations := strtointdef(paramstr(1), num_iterations);
for iter := 1 to num_iterations do
begin
done := false;
for i := low(pairs) to high(pairs) do
pairs[i] := tpair.create;
for i := low(pairs) to high(pairs) do
pairs[i].resume;
sleep(5000);
done := true;
for i := low(pairs) to high(pairs) do
begin
pairs[i].waitfor;
pairs[i].free;
end;
end;
end.
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