Fix typos, bugs, and improve fallback mode compatibility

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "netmap-rs"
 version = "0.1.0"
-edition = "2024"
+edition = "2021"
 authors = ["Meshack Bahati Ouma <bahatikylemeshack@gmail.com"]
 description = "Safe, zero-cost abstractions for Netmap kernel-bypass networking"
 license = "MIT OR Apache-2.0"
@@ -12,8 +12,8 @@ readme = 'README.md'
 
 [features]
 default = []
-sys = ['netmap-min-sys']
-fallback = []
+sys = ['netmap-min-sys', 'core_affinity', 'reed-solomon-erasure'] # For FEC example
+fallback = ['core_affinity'] # Also include for thread_per_ring example under fallback
 
 [dependencies]
 bitflags = "2.0"

README.md

@@ -21,7 +21,7 @@ Add to your  `Cargo.toml`:
 
 ```toml
 
-[dependecies]
+[dependencies]
 netmap-rs ="0.1"
 ```
 
@@ -37,11 +37,11 @@ fn main() -> Result<(), Error> {
         .open()?;
 
     let mut tx_ring = nm.tx_ring(0)?;
-    let mut rx-ring = nm.rx_ring(0)?;
+    let mut rx_ring = nm.rx_ring(0)?;
 
     // send a packet
     tx_ring.send(b"hello world")?;
-    tx.ring.sync();
+    tx_ring.sync();
 
     // receive packets
     while let Some(frame) = rx_ring.recv(){

examples/fec.rs

@@ -1,56 +1,122 @@
-//! Forward Error Correction (FEC) example using Reed-Solomon
+#![cfg(feature = "sys")]
 
 use netmap_rs::prelude::*;
 use reed_solomon_erasure::galois_8::ReedSolomon;
 use std::time::Duration;
 
-const DATA_SHARDS: usize = 4;
-const PARITY_SHARDS: usize = 2;
+// Example: 2 data shards, 1 parity shard
+const DATA_SHARDS: usize = 2;
+const PARITY_SHARDS: usize = 1;
+const TOTAL_SHARDS: usize = DATA_SHARDS + PARITY_SHARDS;
 
 fn main() -> Result<(), Error> {
-    let nm = NetmapBuilder::new("netmap:eth0")
+    let nm = NetmapBuilder::new("netmap:eth0") // Replace with your interface
         .num_tx_rings(1)
         .num_rx_rings(1)
-        .open()?;
+        .build()?;
 
     let mut tx_ring = nm.tx_ring(0)?;
     let mut rx_ring = nm.rx_ring(0)?;
 
-    // Create encoder/decoder
-    let rs = ReedSolomon::new(DATA_SHARDS, PARITY_SHARDS)?;
+    let r = ReedSolomon::new(DATA_SHARDS, PARITY_SHARDS).unwrap();
 
     // Original data
-    let mut data: Vec<Vec<u8>> = (0..DATA_SHARDS).map(|i| vec![i as u8; 128]).collect();
+    let original_data = b"Hello Netmap with FEC!".to_vec();
+    let chunk_size = (original_data.len() + DATA_SHARDS - 1) / DATA_SHARDS;
+    let mut shards = Vec::with_capacity(TOTAL_SHARDS);
 
-    // Add parity shards
-    let mut shards = data.clone();
-    shards.resize(DATA_SHARDS + PARITY_SHARDS, vec![0; 128]);
-    rs.encode(&mut shards)?;
+    for i in 0..DATA_SHARDS {
+        let start = i * chunk_size;
+        let end = std::cmp::min(start + chunk_size, original_data.len());
+        let mut shard = original_data[start..end].to_vec();
+        shard.resize(chunk_size, 0); // Pad if necessary
+        shards.push(shard);
+    }
+    for _ in 0..PARITY_SHARDS {
+        shards.push(vec![0u8; chunk_size]);
+    }
 
-    // Send all shards
-    for shard in &shards {
-        tx_ring.send(shard)?;
+    // Encode
+    r.encode(&mut shards).unwrap();
+
+    // Simulate sending shards (e.g., as separate packets)
+    println!("Sending shards...");
+    for (i, shard) in shards.iter().enumerate() {
+        // In a real scenario, prepend shard index or other metadata
+        let mut packet_data = vec![i as u8]; // Shard index
+        packet_data.extend_from_slice(shard);
+        tx_ring.send(&packet_data)?;
+        println!("Sent shard {}: len {}", i, shard.len());
     }
     tx_ring.sync();
 
-    // Simulate packet loss (drop 2 random shards)
-    let mut received_shards = shards.clone();
-    received_shards[1] = vec![0; 128]; // Mark as missing
-    received_shards[4] = vec![0; 128]; // Mark as missing
+    // Simulate receiving shards (and potentially losing one)
+    let mut received_shards: Vec<Option<Vec<u8>>> = vec![None; TOTAL_SHARDS];
+    let mut received_count = 0;
 
-    // Receive and reconstruct
-    let mut reconstructed = received_shards.clone();
-    rs.reconstruct(&mut reconstructed)?;
+    println!("Receiving shards (simulating loss of shard 0)...");
+    for _ in 0..10 { // Try to receive for a bit
+        rx_ring.sync();
+        while let Some(frame) = rx_ring.recv() {
+            let payload = frame.payload();
+            if payload.is_empty() { continue; }
+            let shard_index = payload[0] as usize;
 
-    // Verify reconstruction
-    for i in 0..DATA_SHARDS {
-        assert_eq!(
-            reconstructed[i], data[i],
-            "Reconstruction failed for shard {}",
-            i
-        );
+            // SIMULATE LOSS OF SHARD 0
+            if shard_index == 0 && received_shards[0].is_none() && received_count < DATA_SHARDS {
+                 println!("Simulated loss of shard 0");
+                 received_shards[0] = Some(vec![]); // Mark as lost for reconstruction logic
+                 // but don't actually store it / increment received_count for it yet
+                 // to ensure reconstruction is attempted.
+                 // For this test, we'll actually skip storing it to force reconstruction.
+                 continue;
+            }
+
+            if shard_index < TOTAL_SHARDS && received_shards[shard_index].is_none() {
+                received_shards[shard_index] = Some(payload[1..].to_vec());
+                received_count += 1;
+                println!("Received shard {}", shard_index);
+            }
+            if received_count >= DATA_SHARDS { break; }
+        }
+        if received_count >= DATA_SHARDS { break; }
+        std::thread::sleep(Duration::from_millis(50));
+    }
+
+
+    if received_count < DATA_SHARDS {
+        eprintln!("Did not receive enough shards to reconstruct.");
+        return Ok(());
+    }
+
+    println!("Attempting reconstruction...");
+    match r.reconstruct(&mut received_shards) {
+        Ok(_) => {
+            println!("Reconstruction successful!");
+            let mut reconstructed_data = Vec::new();
+            for i in 0..DATA_SHARDS {
+                if let Some(shard_data) = &received_shards[i] {
+                    reconstructed_data.extend_from_slice(shard_data);
+                } else {
+                    eprintln!("Missing data shard {} after reconstruction attempt.", i);
+                    return Ok(());
+                }
+            }
+            // Trim padding if original length known, or handle as per application logic
+            reconstructed_data.truncate(original_data.len());
+
+            if reconstructed_data == original_data {
+                println!("Data successfully reconstructed: {:?}", String::from_utf8_lossy(&reconstructed_data));
+            } else {
+                eprintln!("Data mismatch after reconstruction!");
+                eprintln!("Original:       {:?}", String::from_utf8_lossy(&original_data));
+                eprintln!("Reconstructed:  {:?}", String::from_utf8_lossy(&reconstructed_data));
+            }
+        }
+        Err(e) => {
+            eprintln!("Reconstruction failed: {:?}", e);
+        }
     }
 
-    println!("FEC test successful - data reconstructed correctly");
     Ok(())
 }

examples/ping_pong.rs

@@ -1,40 +1,40 @@
-//! A simple ping-pong example demonstrating basic Netmap usage
+#![cfg(feature = "sys")]
 
 use netmap_rs::prelude::*;
-use std::time::{Duration, Instant};
+use std::time::Duration;
 
 fn main() -> Result<(), Error> {
     let nm = NetmapBuilder::new("netmap:eth0")
-        .num_tx_rings(1)
+        .nm_tx_rings(1)
         .num_rx_rings(1)
-        .open()?;
+        .build()?;
 
     let mut tx_ring = nm.tx_ring(0)?;
     let mut rx_ring = nm.rx_ring(0)?;
 
-    let ping_data = b"PING";
-    let pong_data = b"PONG";
-
-    // Ping
-    tx_ring.send(ping_data)?;
+    // send a packet
+    tx_ring.send(b"hello world")?;
     tx_ring.sync();
 
-    let start = Instant::now();
-    let timeout = Duration::from_secs(1);
-
-    // Wait for pong
-    loop {
-        if let Some(frame) = rx_ring.recv() {
-            if frame.payload() == pong_data {
-                let rtt = start.elapsed();
-                println!("Ping-pong round trip: {:?}", rtt);
-                break;
-            }
+    // receive packets
+    let mut received = false;
+    for _ in 0..10 {
+        // try a few times
+        while let Some(frame) = rx_ring.recv() {
+            println!("Received packet: {:?}", frame.payload());
+            assert_eq!(frame.payload(), b"hello world");
+            received = true;
+            break;
         }
-
-        if start.elapsed() > timeout {
-            return Err(Error::WouldBlock);
+        if received {
+            break;
         }
+        std::thread::sleep(Duration::from_millis(100)); // wait for packets
+        rx_ring.sync(); // tell kernel we are done with previous packets
+    }
+
+    if !received {
+        return Err(Error::WouldBlock); // or some other error
     }
 
     Ok(())