Shadesmar
An IPC library that uses the system's shared memory to pass messages. The communication paradigm is either publish-subscibe or RPC similar to ROS and ROS2.
Caution: Pre-alpha software.
Features
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Multiple subscribers and publishers.
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Multithreaded RPC support.
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Uses a circular buffer to pass messages between processes.
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Faster than using the network stack like in the case with ROS.
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Decentralized, without resource starvation.
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No need to define external IDL files for messages. Use C++ classes as message definition.
Publish-Subscribe
Publisher:
#include <shadesmar/memory/copier.h>
#include <shadesmar/pubsub/publisher.h>
int main() {
shm::memory::DefaultCopier cpy;
shm::pubsub::Publisher pub("topic_name", &cpy);
const uint32_t data_size = 1024;
void *data = malloc(data_size);
for (int i = 0; i < 1000; ++i) {
p.publish(msg, data_size);
}
}Subscriber:
#include <shadesmar/memory/copier.h>
#include <shadesmar/pubsub/subscriber.h>
void callback(shm::memory::Memblock *msg) {
// `msg->ptr` to access `data`
// `msg->size` to access `size`
// The memory will be free'd at the end of this callback.
// Copy to another memory location if you want to persist the data.
// Alternatively, if you want to avoid the copy, you can call
// `msg->no_delete()` which prevents the memory from being deleted
// at the end of the callback.
}
int main() {
shm::memory::DefaultCopier cpy;
shm::pubsub::Subscriber sub("topic_name", &cpy, callback);
// Using `spinOnce` with a manual loop
while(true) {
sub.spin_once();
}
// OR
// Using `spin`
sub.spin();
}