ve3wwg / Coroutines_Boost_0_53

Coroutine framework based upon Boost_0_53 (CentOS7) boost::context

Coroutine Class using Boost 1.53

Requires boost_context 1.53.0 library.

CoroutineMain:

supplies the context for a main thread, already owning
a thread (line a main() program).

Coroutine:

is used for a new context, requiring a stack
to be allocated.

Coroutine co1(myfunc[,stack_size]);

When stack_size is not supplied, a minimum stack is
allocated.

CoroutineBase:

class from which Coroutine and CoroutineMain classes
are derived.

CoroutineBase::yield(CoroutineBase& co)

This method transfers control from the current coroutine
(or main thread) to the new coroutine.

CoroutineBase::fun_t

This is the function pointer to the code to be run as
a coroutine. It is passed the CoroutineBase pointer 
of the executing coroutine (either Coroutine or 
CoroutineMain class). The function must return its
Coroutine class pointer. 

Control is yielded by specifying the Coroutine class
to pass control to.

To pass data, derive a class from Coroutine or Coroutine
main as required.

CoroutineBase *fun1(CoroutineBase *co) {

    co->yield(...);
    ...
    return co;
}

Starting a coroutine from main:

CoroutineMain mco;
    
int main(int argc,char **argv) {
    Coroutine co1(fun1);

    mco.yield(co1);

Build:

make [BOOST=$HOME/local]

./coroutine # test program

Test Example:

#include "coroutine.hpp"

CoroutineMain mco;
Coroutine *cr1, *cr2;

static CoroutineBase *
fun1(CoroutineBase *co) {
	int x=10;

	std::cout << "fun1::a x=" << x++ << '\n';
	co->yield(*cr2);

	std::cout << "fun1::b x=" << x++ << '\n';
	co->yield(*cr2);

	return co;
}

static CoroutineBase *
fun2(CoroutineBase *co) {
	int x=20;

	std::cout << "fun2::a x=" << x++ << '\n';
	co->yield(mco);

	std::cout << "fun2::b x=" << x++ << '\n';
	co->yield(mco);

	return co;
}

int
main(int argc,char **argv) {
	Coroutine co1(fun1), co2(fun2);

	cr1 = &co1;
	cr2 = &co2;
	mco.yield(co1);
	std::cout << "Back to main a..\n";
	mco.yield(co1);
	std::cout << "Back to main b..\n";
	return 0;
}

Example Output:

$ ./coroutine 
fun1::a x=10
fun2::a x=20
Back to main a..
fun1::b x=11
fun2::b x=21
Back to main b..

Server Example:

$ ./server 

Will cause it to listen to 127.0.0.1:2345

Client Test:

$ wget http://127.0.0.1:2345/whatever/params?pig=oink --save-headers -qO-
HTTP/1.1 200 OK 
Connection: Keep-Alive
Content-Length: 209

Request type: GET
Request path: /whatever/params?pig=oink
Http Version: HTTP/1.1
Request Headers were:
Hdr: HOST: 127.0.0.1:2345
Hdr: CONNECTION: Keep-Alive
Hdr: ACCEPT: */*
Hdr: USER-AGENT: Wget/1.16
$