commit ed9027d12c4ad6b2febdccc74fdc5f431ba9023f
Author: Albin Chaboissier <chalbin73@gmail.com>
Date:   Thu Mar 5 23:03:21 2026 +0100

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
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diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..e11f367
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,181 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
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+
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+ "ntw_flowgraph",
+ "ntw_flowgraph_macros",
+ "ringbuf",
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+ "ntw_flowgraph_macros",
+ "petgraph",
+ "ringbuf",
+]
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diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..47a9577
--- /dev/null
+++ b/Cargo.toml
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+
+[dependencies]
+ntw_flowgraph = {path = "ntw_flowgraph"}
+ntw_flowgraph_macros = {path = "ntw_flowgraph_macros"}
+ringbuf = "0.4.8"
diff --git a/ntw_flowgraph/.gitignore b/ntw_flowgraph/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/ntw_flowgraph/.gitignore
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diff --git a/ntw_flowgraph/Cargo.lock b/ntw_flowgraph/Cargo.lock
new file mode 100644
index 0000000..260d5b4
--- /dev/null
+++ b/ntw_flowgraph/Cargo.lock
@@ -0,0 +1,172 @@
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+# It is not intended for manual editing.
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+
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+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
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diff --git a/ntw_flowgraph/Cargo.toml b/ntw_flowgraph/Cargo.toml
new file mode 100644
index 0000000..b343aa2
--- /dev/null
+++ b/ntw_flowgraph/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "ntw_flowgraph"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+petgraph = "0.8.3"
+ringbuf = "0.4.8"
+ntw_flowgraph_macros = {path = "../ntw_flowgraph_macros/"}
diff --git a/ntw_flowgraph/src/graph.rs b/ntw_flowgraph/src/graph.rs
new file mode 100644
index 0000000..fdf0653
--- /dev/null
+++ b/ntw_flowgraph/src/graph.rs
@@ -0,0 +1,86 @@
+use petgraph::graph::DiGraph;
+use petgraph::graph::NodeIndex;
+
+use crate::Block;
+
+pub struct Graph
+{
+    blocks: Vec<Box<dyn Block>>,
+}
+
+impl Graph
+{
+    pub fn new() -> Graph
+    {
+        Graph { blocks: vec![] }
+    }
+
+    pub fn add_block(&mut self, block: impl Block + 'static)
+    {
+        block.set_block_index(self.blocks.len());
+        self.blocks.push(Box::new(block));
+    }
+
+    pub fn run(&mut self)
+    {
+        // Compute the topo_order
+        let mut digraph = DiGraph::<(), (), usize>::with_capacity(self.blocks.len(), 1);
+
+        for block in self.blocks.iter()
+        {
+            let node = digraph.add_node(());
+
+            for next in block.get_successors()
+            {
+                digraph.add_edge(node, next.into(), ());
+            }
+        }
+
+        let topo_order = petgraph::algo::toposort(&digraph, None)
+            .expect("Graph cannot be cylic")
+            .into_iter()
+            .map(|x| x.index())
+            .collect::<Vec<_>>();
+
+        // Dumbass round robin
+        loop
+        {
+            let mut one_ready = false;
+            for x in topo_order.iter()
+            {
+                let block = &mut self.blocks[*x];
+                if block.ready()
+                {
+                    block.work();
+                    one_ready = true;
+                }
+            }
+
+            if !one_ready
+            {
+                break;
+            }
+        }
+    }
+
+    pub fn print_deps(&self)
+    {
+        for (i, e) in self.blocks.iter().enumerate()
+        {
+            print!("{}: ", i);
+            for x in e.get_successors()
+            {
+                print!("{}, ", x);
+            }
+            println!();
+        }
+    }
+}
+
+impl Default for Graph
+{
+    fn default() -> Self
+    {
+        Self::new()
+    }
+}
diff --git a/ntw_flowgraph/src/inout.rs b/ntw_flowgraph/src/inout.rs
new file mode 100644
index 0000000..f7390df
--- /dev/null
+++ b/ntw_flowgraph/src/inout.rs
@@ -0,0 +1,65 @@
+use ringbuf::HeapRb;
+use ringbuf::SharedRb;
+use ringbuf::storage::Heap;
+use ringbuf::traits::Producer;
+use ringbuf::traits::Split;
+use ringbuf::wrap::caching::Caching;
+use std::cell::Cell;
+use std::rc::Rc;
+use std::sync::Arc;
+
+// Represent a block input, of which data is popped
+pub struct In<T>
+{
+    block: Rc<Cell<Option<usize>>>,
+    pub rb: Caching<Arc<SharedRb<Heap<T>>>, false, true>,
+}
+
+// Represent a block input, in which data is pushed
+pub struct Out<T>
+{
+    to: Rc<Cell<Option<usize>>>,
+    pub rb: Caching<Arc<SharedRb<Heap<T>>>, true, false>,
+}
+
+pub struct Stream;
+
+impl Stream
+{
+    pub fn make<T>(length: usize) -> (Out<T>, In<T>)
+    {
+        let (prod, cons) = HeapRb::<T>::new(length).split();
+        let to = Rc::new(Cell::new(None));
+        (
+            Out {
+                to: to.clone(),
+                rb: prod,
+            },
+            In {
+                block: to.clone(),
+                rb: cons,
+            },
+        )
+    }
+}
+
+impl<T> In<T>
+{
+    pub fn set_index(&self, index: usize)
+    {
+        self.block.set(Some(index))
+    }
+}
+
+impl<T> Out<T>
+{
+    pub fn get_successor(&self) -> Option<usize>
+    {
+        self.to.get()
+    }
+
+    pub fn try_push(&mut self, data: T) -> Result<(), T>
+    {
+        self.rb.try_push(data)
+    }
+}
diff --git a/ntw_flowgraph/src/lib.rs b/ntw_flowgraph/src/lib.rs
new file mode 100644
index 0000000..16337b6
--- /dev/null
+++ b/ntw_flowgraph/src/lib.rs
@@ -0,0 +1,14 @@
+pub mod graph;
+pub mod inout;
+
+pub trait BlockWork
+{
+    fn work(&mut self);
+    fn ready(&self) -> bool;
+}
+
+pub trait Block: BlockWork
+{
+    fn set_block_index(&self, index: usize);
+    fn get_successors(&self) -> Vec<usize>;
+}
diff --git a/ntw_flowgraph_macros/.gitignore b/ntw_flowgraph_macros/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/ntw_flowgraph_macros/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/ntw_flowgraph_macros/Cargo.lock b/ntw_flowgraph_macros/Cargo.lock
new file mode 100644
index 0000000..5a50dce
--- /dev/null
+++ b/ntw_flowgraph_macros/Cargo.lock
@@ -0,0 +1,47 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.106"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8fd00f0bb2e90d81d1044c2b32617f68fcb9fa3bb7640c23e9c748e53fb30934"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "streams_macros"
+version = "0.1.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "syn"
+version = "2.0.117"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
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diff --git a/ntw_flowgraph_macros/Cargo.toml b/ntw_flowgraph_macros/Cargo.toml
new file mode 100644
index 0000000..7361208
--- /dev/null
+++ b/ntw_flowgraph_macros/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "ntw_flowgraph_macros"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0.106"
+quote = "1.0.45"
+syn = {version = "2.0.117", features = ["extra-traits"]}
diff --git a/ntw_flowgraph_macros/src/lib.rs b/ntw_flowgraph_macros/src/lib.rs
new file mode 100644
index 0000000..1055f61
--- /dev/null
+++ b/ntw_flowgraph_macros/src/lib.rs
@@ -0,0 +1,126 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::DeriveInput;
+use syn::Ident;
+use syn::parse_macro_input;
+
+struct BlockDerive
+{
+    input_fields: Vec<Ident>,
+    output_fields: Vec<Ident>,
+}
+
+fn set_block_index_func(ctx: &BlockDerive) -> proc_macro2::TokenStream
+{
+    let inputs = ctx.input_fields.clone();
+    quote! {
+        fn set_block_index(&self, index: usize)
+        {
+            #({
+                self.#inputs.set_index(index);
+            })*
+        }
+    }
+}
+
+fn get_successors_func(ctx: &BlockDerive) -> proc_macro2::TokenStream
+{
+    let outputs = ctx.output_fields.clone();
+    quote! {
+        fn get_successors(&self) -> Vec<usize>
+        {
+            let mut output = vec![];
+            #(
+                match self.#outputs.get_successor()
+                {
+                    None => {},
+                    Some(x) => output.push(x)
+                }
+            )*
+
+            output
+        }
+    }
+}
+
+#[proc_macro_derive(Block, attributes(input, output))]
+pub fn block_derive(item: TokenStream) -> TokenStream
+{
+    let cloned = item.clone();
+    let input = parse_macro_input!(cloned as DeriveInput);
+
+    let data_struct = match input.data
+    {
+        syn::Data::Struct(data_struct) => data_struct,
+        syn::Data::Enum(_) | syn::Data::Union(_) => panic!(),
+    };
+
+    let struct_fields = match data_struct.fields
+    {
+        syn::Fields::Named(fields_named) => fields_named,
+        syn::Fields::Unnamed(_) | syn::Fields::Unit => panic!(),
+    };
+
+    let input_fields = struct_fields
+        .named
+        .iter()
+        .filter_map(|f| {
+            if f.ident.is_some()
+                && f.attrs.iter().any(|attr| {
+                    attr.meta
+                        .path()
+                        .segments
+                        .last()
+                        .is_some_and(|s| s.ident == "input")
+                })
+            {
+                Some(f.ident.clone().unwrap())
+            }
+            else
+            {
+                None
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let output_fields = struct_fields
+        .named
+        .iter()
+        .filter_map(|f| {
+            if f.ident.is_some()
+                && f.attrs.iter().any(|attr| {
+                    attr.meta
+                        .path()
+                        .segments
+                        .last()
+                        .is_some_and(|s| s.ident == "output")
+                })
+            {
+                Some(f.ident.clone().unwrap())
+            }
+            else
+            {
+                None
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let derive = BlockDerive {
+        input_fields,
+        output_fields,
+    };
+
+    let set_index_func = set_block_index_func(&derive);
+    let get_successors_func = get_successors_func(&derive);
+    let struct_path = input.ident;
+
+    //item
+    quote! {
+        impl Block for #struct_path
+        {
+            #set_index_func
+            #get_successors_func
+        }
+    }
+    .into()
+}
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..ed3ef91
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,143 @@
+use ntw_flowgraph::Block;
+use ntw_flowgraph::BlockWork;
+use ntw_flowgraph::graph::Graph;
+use ntw_flowgraph::inout::In;
+use ntw_flowgraph::inout::Out;
+use ntw_flowgraph::inout::Stream;
+use ntw_flowgraph_macros::Block;
+use ringbuf::traits::Consumer;
+use ringbuf::traits::Observer;
+use ringbuf::traits::Producer;
+
+#[derive(Block)]
+pub struct VecSource
+{
+    vector: Vec<u32>,
+
+    #[output]
+    out: Out<u32>,
+}
+
+impl BlockWork for VecSource
+{
+    fn work(&mut self)
+    {
+        while let Some(element) = self.vector.pop()
+        {
+            match self.out.rb.try_push(element)
+            {
+                Ok(()) =>
+                {}
+                Err(x) =>
+                {
+                    self.vector.push(x);
+                    break;
+                }
+            }
+        }
+    }
+
+    fn ready(&self) -> bool
+    {
+        self.vector.len() > 0 && self.out.rb.vacant_len() > 0
+    }
+}
+
+impl VecSource
+{
+    pub fn new(vector: Vec<u32>) -> (VecSource, In<u32>)
+    {
+        let (out, stream) = Stream::make(16);
+        (VecSource { vector, out }, stream)
+    }
+}
+
+#[derive(Block)]
+pub struct Adder
+{
+    #[input]
+    in_a: In<u32>,
+
+    #[input]
+    in_b: In<u32>,
+
+    #[output]
+    out: Out<u32>,
+}
+
+impl BlockWork for Adder
+{
+    fn work(&mut self)
+    {
+        while let Some(a) = self.in_a.rb.try_pop()
+            && let Some(b) = self.in_b.rb.try_pop()
+            && self.out.rb.vacant_len() > 0
+        {
+            let _ = self.out.rb.try_push(a + b);
+        }
+    }
+
+    fn ready(&self) -> bool
+    {
+        self.in_a.rb.occupied_len() > 0
+            && self.in_b.rb.occupied_len() > 0
+            && self.out.rb.vacant_len() > 0
+    }
+}
+
+impl Adder
+{
+    pub fn new(in_a: In<u32>, in_b: In<u32>) -> (Adder, In<u32>)
+    {
+        let (out, stream) = Stream::make(16);
+        (Adder { in_a, in_b, out }, stream)
+    }
+}
+
+#[derive(Block)]
+pub struct PrintSink
+{
+    #[input]
+    stream: In<u32>,
+}
+
+impl BlockWork for PrintSink
+{
+    fn work(&mut self)
+    {
+        if let Some(x) = self.stream.rb.try_pop()
+        {
+            println!("{x}");
+        }
+    }
+
+    fn ready(&self) -> bool
+    {
+        self.stream.rb.occupied_len() > 0
+    }
+}
+
+impl PrintSink
+{
+    pub fn new(stream: In<u32>) -> PrintSink
+    {
+        PrintSink { stream }
+    }
+}
+
+fn main()
+{
+    let (vector_a, a) = VecSource::new((0..15).collect());
+    let (vector_b, b) = VecSource::new((0..15).collect());
+    let (adder, sum) = Adder::new(a, b);
+    let printer = PrintSink::new(sum);
+
+    let mut graph = Graph::new();
+
+    graph.add_block(printer);
+    graph.add_block(adder);
+    graph.add_block(vector_a);
+    graph.add_block(vector_b);
+
+    graph.run();
+}