From 3a68f2f3e8b4a27be2bb9a9653d7e9f367e457d8 Mon Sep 17 00:00:00 2001
From: Marcin Kondej <markondej@gmail.com>
Date: Fri, 27 Sep 2019 01:02:17 +0200
Subject: [PATCH] Using lambda functions

---
 transmitter.cpp | 74 +++++++++++++++++++++++--------------------------
 wave_reader.cpp |  7 +----
 2 files changed, 36 insertions(+), 45 deletions(-)

diff --git a/transmitter.cpp b/transmitter.cpp
index 6df424d..beb9eb1 100644
--- a/transmitter.cpp
+++ b/transmitter.cpp
@@ -287,8 +287,12 @@ void Transmitter::transmit(WaveReader &reader, float frequency, float bandwidth,
         output = initClockOutput();
     }
 
-    bool errorCatched = false;
-    std::string errorMessage;
+    auto finally = [&]() {
+        if (!preserveCarrier) {
+            closeClockOutput(output);
+            output = nullptr;
+        }
+    };
 
     try {
         if (dmaChannel != 0xFF) {
@@ -298,18 +302,11 @@ void Transmitter::transmit(WaveReader &reader, float frequency, float bandwidth,
         }
     } catch (std::runtime_error &catched) {
         preserveCarrier = false;
-        errorMessage = catched.what();
-        errorCatched = true;
+        finally();
+        throw catched;
     }
 
-    if (!preserveCarrier) {
-        closeClockOutput(output);
-        output = nullptr;
-    }
-
-    if (errorCatched) {
-        throw std::runtime_error(errorMessage);
-    }
+    finally();
 }
 
 void Transmitter::transmitViaCpu(WaveReader &reader, uint32_t bufferSize)
@@ -322,12 +319,16 @@ void Transmitter::transmitViaCpu(WaveReader &reader, uint32_t bufferSize)
     sampleOffset = 0;
     loadedSamples = &samples;
 
-    bool eof = samples.size() < bufferSize, errorCatched = false;
+    bool eof = samples.size() < bufferSize;
     std::thread txThread(Transmitter::transmitThread);
-    std::string errorMessage;
 
     usleep(BUFFER_TIME / 2);
 
+    auto finally = [&]() {
+        transmitting = false;
+        txThread.join();
+    };
+
     try {
         while (!eof && transmitting) {
             if (loadedSamples == nullptr) {
@@ -344,14 +345,11 @@ void Transmitter::transmitViaCpu(WaveReader &reader, uint32_t bufferSize)
             usleep(BUFFER_TIME / 2);
         }
     } catch (std::runtime_error &catched) {
-        errorMessage = catched.what();
-        errorCatched = true;
-    }
-    transmitting = false;
-    txThread.join();
-    if (errorCatched) {
-        throw std::runtime_error(errorMessage);
+        finally();
+        throw catched;
     }
+
+    finally();
 }
 
 void Transmitter::transmitViaDma(WaveReader &reader, uint32_t bufferSize, uint8_t dmaChannel)
@@ -410,11 +408,22 @@ void Transmitter::transmitViaDma(WaveReader &reader, uint32_t bufferSize, uint8_
     *pwmFifoData = 0x00000000;
 
     volatile DMARegisters *dma = startDma(dmaMemory, dmaCb, dmaChannel);
-    bool errorCatched = false;
-    std::string errorMessage;
 
     usleep(BUFFER_TIME / 4);
 
+    auto finally = [&]() {
+        dmaCb[(cbOffset < 2 * bufferSize) ? cbOffset : 0].nextCbAddress = 0x00000000;
+        while (dma->cbAddress != 0x00000000) {
+            usleep(1000);
+        }
+
+        closeDma(dma);
+        closePwmController(pwm);
+
+        freeMemory(dmaMemory);
+        transmitting = false;
+    };
+
     try {
         while (!eof && transmitting) {
             samples = reader.getSamples(bufferSize, transmitting);
@@ -436,24 +445,11 @@ void Transmitter::transmitViaDma(WaveReader &reader, uint32_t bufferSize, uint8_
             }
         }
     } catch (std::runtime_error &catched) {
-        errorMessage = catched.what();
-        errorCatched = true;
+        finally();
+        throw catched;
     }
 
-    dmaCb[(cbOffset < 2 * bufferSize) ? cbOffset : 0].nextCbAddress = 0x00000000;
-    while (dma->cbAddress != 0x00000000) {
-        usleep(1000);
-    }
-
-    closeDma(dma);
-    closePwmController(pwm);
-
-    freeMemory(dmaMemory);
-    transmitting = false;
-
-    if (errorCatched) {
-        throw std::runtime_error(errorMessage);
-    }
+    finally();
 }
 
 void Transmitter::transmitThread()
diff --git a/wave_reader.cpp b/wave_reader.cpp
index 9a40840..b91bd34 100644
--- a/wave_reader.cpp
+++ b/wave_reader.cpp
@@ -142,12 +142,7 @@ std::vector<Sample> WaveReader::getSamples(uint32_t quantity, bool &continueFlag
         quantity = bytesToRead / bytesPerSample;
     }
 
-    std::vector<uint8_t> data;
-    try {
-        data = readData(bytesToRead, false, continueFlag);
-    } catch (std::runtime_error &error) {
-        throw error;
-    }
+    std::vector<uint8_t> data = readData(bytesToRead, false, continueFlag);
     if (data.size() < bytesToRead) {
         quantity = data.size() / bytesPerSample;
     }