C Split

Makefile-based template to build C code with live reload.

Quickstart

Oneliner to init everything:

curl https://raw.githubusercontent.com/badrpas/c-dyn-split/master/Makefile > Makefile && make init

Then build

make

This will produce out/main.host executable and out/sub.dyn.so. Run the out/main.host and keep it running.

Update src/sub.dyn.c, rebuild with make and observe the change applied.

Done.

Example

// hello.dyn.c
// The .dyn suffix marks it as a reloadable

#include <stdio.h>

void say_hello() {
    printf("Hello from lib\n");
}

// main.c

// This "declares" say_hello() function.
// When built as `make split`, it actually implements a proxy function(s).
// But does declarations otherwise for `make unified` build and proper LSP/intellisense.
#include "hello.dyn.gen.h" 

extern unsigned int sleep (unsigned int __seconds); // or `#include <unistd.h>`

int main () {
    while (1) {
        cdynsplit_update(); // Load/update the hello.dyn.c code
        say_hello();        // Call the "remote" function in regular way
        sleep(1);           // To not overspam it
    }
    return 0;
}

Build by running make split. This will produce out/hello.dyn.so lib and out/main.host executable.

Run it to get endless loop of hello messages.

Change the message in say_hello. Execute make split again (while out/main.host is still running).

??? Profit

How it works

Makefile builds %.dyn.c files as dynamic libraries (.so) and generates headers files for them (.dyn.gen.h).

From calling side (host) it is as easy as to include the header and call the function as you would normally.

Headers include implementation proxy function that contains a pointer to remote (.so) counterpart function.

Host should call upd_dyn() to load libs and/or poll for their changes. It also resolves pointers in proxy functions to latest version.

Currenlty function proxies are generated via js script and make will install bun runtime if not found with which bun.

todo

• migrate codegen to c
• encapsulate everything in one dir
• better initial setup experience (curl? single Makefile download?)