setjmp/longtest behavior test in D

sjlj_test.d

import core.sys.posix.setjmp;
import std.stdio;
import std.format;

string yield(alias callee_env, alias caller_env, alias val)() {
  return q{
    if (setjmp(%s) == 0) {
      longjmp(%s, %s);
    }
  }.format(callee_env.stringof, caller_env.stringof, val);
}

string yield_ptr(alias callee_env_ptr, alias caller_env_ptr, alias val)() {
  return q{
    if (setjmp(*%s) == 0) {
      longjmp(*%s, %s);
    }
  }.format(callee_env_ptr.stringof, caller_env_ptr.stringof, val);
}

void func1(alias callee_env, alias caller_env)() {
  enum FNAME = __FUNCTION__;
  writefln("<%s> addr of callee_env: %s, addr of callee_env: %s", FNAME, &callee_env, &caller_env);

  writefln("<%s> A", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> B", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> C", FNAME);
  mixin (yield!(callee_env, caller_env, -1));
}

void func2(jmp_buf callee_env, jmp_buf caller_env) {
  enum FNAME = __FUNCTION__;
  writefln("<%s> addr of callee_env: %s, addr of callee_env: %s", FNAME, &callee_env, &caller_env);

  writefln("<%s> A", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> B", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> C", FNAME);
  mixin (yield!(callee_env, caller_env, -1));
}

void func3(ref jmp_buf callee_env, ref jmp_buf caller_env) {
  enum FNAME = __FUNCTION__;
  writefln("<%s> addr of callee_env: %s, addr of callee_env: %s", FNAME, &callee_env, &caller_env);

  writefln("<%s> A", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> B", FNAME);
  mixin (yield!(callee_env, caller_env, 1));

  writefln("<%s> C", FNAME);
  mixin (yield!(callee_env, caller_env, -1));
}

void func4(jmp_buf* callee_env, jmp_buf* caller_env) {
  enum FNAME = __FUNCTION__;
  writefln("<%s> addr of callee_env: %s, addr of callee_env: %s", FNAME, callee_env, caller_env);

  writefln("<%s> A", FNAME);
  mixin (yield_ptr!(callee_env, caller_env, 1));

  writefln("<%s> B", FNAME);
  mixin (yield_ptr!(callee_env, caller_env, 1));

  writefln("<%s> C", FNAME);
  mixin (yield_ptr!(callee_env, caller_env, -1));
}

void test_func1(alias callee_env, alias caller_env)() {
  const status = setjmp(caller_env);

  if (status == 0) {
    func1!(callee_env, caller_env);
  } else if (status != -1) {
    writefln("RESUME!");
    longjmp(callee_env, 1);
  } else if (status == -1) {
    writefln("Fiber finished");
  }
}

void test_func2(alias callee_env, alias caller_env)() {
  const status = setjmp(caller_env);

  if (status == 0) {
    func2(callee_env, caller_env);
  } else if (status != -1) {
    writefln("resume!");
    longjmp(callee_env, 1);
  } else if (status == -1) {
    writefln("fiber finished");
  }
}

void test_func3(alias callee_env, alias caller_env)() {
  const status = setjmp(caller_env);

  if (status == 0) {
    func3(callee_env, caller_env);
  } else if (status != -1) {
    writefln("resume!");
    longjmp(callee_env, 1);
  } else if (status == -1) {
    writefln("fiber finished");
  }
}

void test_func4(alias callee_env, alias caller_env)() {
  const status = setjmp(caller_env);

  if (status == 0) {
    func4(&callee_env, &caller_env);
  } else if (status != -1) {
    writefln("resume!");
    longjmp(callee_env, 1);
  } else if (status == -1) {
    writefln("fiber finished");
  }
}

void main(string[] args) {
  __gshared jmp_buf callee_env;
  __gshared jmp_buf caller_env;
  writefln("TEST <%s>-------------------------------------", "func1");
  test_func1!(callee_env, caller_env);
  writefln("TEST <%s>-------------------------------------", "func2");
  test_func2!(callee_env, caller_env);
  writefln("TEST <%s>-------------------------------------", "func3");
  test_func3!(callee_env, caller_env);
  writefln("TEST <%s>-------------------------------------", "func4");
  test_func4!(callee_env, caller_env);
}