Rework fl2k buffer size

3 files changed, 47 insertions, 14 deletions

diff --git a/build.rs b/build.rs
index 0c7e0f9..8542b19 100644
--- a/build.rs
+++ b/build.rs
@@ -18,7 +18,7 @@ fn main() {
     println!("cargo:rustc-link-lib=usb-1.0");
 
     // Tell cargo to invalidate the built crate whenever the wrapper changes
-    println!("cargo:rerun-if-changed=c_sources/osmo-fl2k.h");
+    println!("cargo:rerun-if-changed=c_sources/*");
 
     let bindings = bindgen::Builder::default()
         .header("c_sources/osmo-fl2k.h")
diff --git a/src/fl2k.rs b/src/fl2k.rs
index a17a04d..695d32a 100644
--- a/src/fl2k.rs
+++ b/src/fl2k.rs
@@ -1,5 +1,7 @@
-use std::{ffi::{c_int, c_void}, sync::mpsc};
-use fl2k_ampliphase::{fl2k_dev_t, fl2k_get_device_count, fl2k_open, fl2k_close, fl2k_stop_tx, fl2k_set_sample_rate, fl2k_get_sample_rate, fl2k_start_tx};
+use std::{ffi::{c_int, c_void}, sync::mpsc, mem::swap};
+use fl2k_ampliphase::{fl2k_dev_t, fl2k_get_device_count, fl2k_open, fl2k_close, fl2k_stop_tx, fl2k_set_sample_rate, fl2k_get_sample_rate, fl2k_start_tx, FL2K_BUF_LEN};
+
+const BUF_LEN : usize = FL2K_BUF_LEN as usize;
 
 #[derive(Debug)]
 pub enum FL2KError {
@@ -32,6 +34,9 @@ pub struct FL2K {
     device: *mut fl2k_dev_t,
     callback_ctx: Box<CallbackCtx>,
     tx : mpsc::SyncSender<(Vec<i8>, Vec<i8>)>,
+
+    r_buf : Vec<i8>,
+    g_buf : Vec<i8>
 }
 
 pub struct CallbackCtx {
@@ -88,7 +93,11 @@ impl FL2K {
             abort: false,
         };
         unsafe {
-            let mut fl2k = FL2K { device: std::mem::zeroed(), callback_ctx: Box::new(ctx), tx };
+
+            let r_buf = Vec::with_capacity(2 * BUF_LEN);
+            let g_buf = Vec::with_capacity(2 * BUF_LEN);
+
+            let mut fl2k = FL2K { device: std::mem::zeroed(), callback_ctx: Box::new(ctx), tx, r_buf, g_buf };
             handle_return_value(fl2k_open(&mut fl2k.device, device_index))?;
             Ok(fl2k)
         }
@@ -118,11 +127,25 @@ impl FL2K {
         handle_return_value( unsafe { fl2k_stop_tx(self.device) } )
     }
 
-    pub fn send(&self, r_buf: Vec<i8>, g_buf: Vec<i8>) -> bool {
+    pub fn send(&mut self, mut r_buf: Vec<i8>, mut g_buf: Vec<i8>) -> bool {
         if r_buf.len() != g_buf.len() {
             panic!("r_buf and g_buf must have same length");
         }
-        self.tx.send((r_buf, g_buf)).is_ok()
+
+        self.r_buf.append(&mut r_buf);
+        self.g_buf.append(&mut g_buf);
+
+        if self.r_buf.len() >= BUF_LEN {
+            let mut r = self.r_buf.split_off(BUF_LEN);
+            let mut g = self.g_buf.split_off(BUF_LEN);
+            /* self.r_buf contains head, r contains tail. Swap them, as we want to give the head and keep the tail. */
+            swap(&mut r, &mut self.r_buf);
+            swap(&mut g, &mut self.g_buf);
+            self.tx.send((r, g)).is_ok()
+        }
+        else {
+            true
+        }
     }
 }
 
diff --git a/src/main.rs b/src/main.rs
index 38a34d4..0814506 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2022 by Matthias P. Braendli <matthias.braendli@mpb.li>
+ * Copyright (C) 2023 by Matthias P. Braendli <matthias.braendli@mpb.li>
  *
  * Based on previous work by
  * Copyright (C) 2022 by Felix Erckenbrecht <eligs@eligs.de>
@@ -245,14 +245,20 @@ fn main() {
                 )
             };
 
-            if let Err(e) = source_file.read_exact(&mut buf_u8) {
-                if e.kind() != std::io::ErrorKind::UnexpectedEof {
-                    eprintln!("Input file read stopped {:?}", e);
-                }
-                else {
-                    eprintln!("Input file EOF reached");
+            match source_file.read(&mut buf_u8) {
+                Ok(len) => {
+                    if len == 0 {
+                        if let Err(e_seek) = source_file.rewind() {
+                            eprintln!("Failed to rewind source file: {}", e_seek);
+                            break;
+                        }
+                    }
+                    buf.resize(len, 0);
+                },
+                Err(e) => {
+                    eprintln!("Failed to read source file: {}", e);
+                    break;
                 }
-                break;
             }
 
             let buf: Vec<f32> = buf
@@ -271,6 +277,8 @@ fn main() {
                 break;
             }
         }
+
+        eprintln!("Leaving input thread");
     });
 
     // Read samples, calculate PD and PDSLOPE
@@ -326,6 +334,7 @@ fn main() {
                 break;
             }
         }
+        eprintln!("Leaving pd thread");
     });
 
     // Read PD and PDSLOPE, interpolate to higher rate
@@ -374,6 +383,7 @@ fn main() {
                 }
             }
         }
+        eprintln!("Leaving dds thread");
     });
 
     // Main thread, output to file/device