From 135e912f3ef435f763e4a68b2dc22da6d33ebc85 Mon Sep 17 00:00:00 2001
From: h3ndrik <hendrik+dev@xd0.de>
Date: Mon, 20 Aug 2018 16:53:59 +0200
Subject: [PATCH] increase max buffer size beyond 64k (#117)

The ESP32 can easily handle a buffer size greater than UINT16_MAX (64KB)
so make the size an uint32_t.
---
 src/AudioFileSourceBuffer.cpp | 24 ++++++++++++------------
 src/AudioFileSourceBuffer.h   | 12 ++++++------
 2 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/src/AudioFileSourceBuffer.cpp b/src/AudioFileSourceBuffer.cpp
index abd9947d..888944d1 100644
--- a/src/AudioFileSourceBuffer.cpp
+++ b/src/AudioFileSourceBuffer.cpp
@@ -23,7 +23,7 @@
 
 #pragma GCC optimize ("O3")
 
-AudioFileSourceBuffer::AudioFileSourceBuffer(AudioFileSource *source, int buffSizeBytes)
+AudioFileSourceBuffer::AudioFileSourceBuffer(AudioFileSource *source, uint32_t buffSizeBytes)
 {
   buffSize = buffSizeBytes;
   buffer = (uint8_t*)malloc(sizeof(uint8_t) * buffSize);
@@ -36,7 +36,7 @@ AudioFileSourceBuffer::AudioFileSourceBuffer(AudioFileSource *source, int buffSi
   filled = false;
 }
 
-AudioFileSourceBuffer::AudioFileSourceBuffer(AudioFileSource *source, void *inBuff, int buffSizeBytes)
+AudioFileSourceBuffer::AudioFileSourceBuffer(AudioFileSource *source, void *inBuff, uint32_t buffSizeBytes)
 {
   buffSize = buffSizeBytes;
   buffer = (uint8_t*)inBuff;
@@ -149,24 +149,24 @@ void AudioFileSourceBuffer::fill()
   if (length < buffSize) {
     // Now try and opportunistically fill the buffer
     if (readPtr > writePtr) {
-        int bytesAvailMid = readPtr - writePtr - 1;
-        if (bytesAvailMid > 0) {
-          int cnt = src->readNonBlock(&buffer[writePtr], bytesAvailMid);
-          length += cnt;
-          writePtr = (writePtr + cnt) % buffSize;
-        }
+      if (readPtr == writePtr+1) return;
+      uint32_t bytesAvailMid = readPtr - writePtr - 1;
+      int cnt = src->readNonBlock(&buffer[writePtr], bytesAvailMid);
+      length += cnt;
+      writePtr = (writePtr + cnt) % buffSize;
       return;
     }
 
-    int bytesAvailEnd = buffSize - writePtr;
-    if (bytesAvailEnd > 0) {
+    if (buffSize > writePtr) {
+      uint32_t bytesAvailEnd = buffSize - writePtr;
       int cnt = src->readNonBlock(&buffer[writePtr], bytesAvailEnd);
       length += cnt;
       writePtr = (writePtr + cnt) % buffSize;
       if (cnt != bytesAvailEnd) return;
     }
-    int bytesAvailStart = readPtr - 1;
-    if (bytesAvailStart > 0) {
+
+    if (readPtr > 1) {
+      uint32_t bytesAvailStart = readPtr - 1;
       int cnt = src->readNonBlock(&buffer[writePtr], bytesAvailStart);
       length += cnt;
       writePtr = (writePtr + cnt) % buffSize;
diff --git a/src/AudioFileSourceBuffer.h b/src/AudioFileSourceBuffer.h
index cc4e659c..6c8dc6c2 100644
--- a/src/AudioFileSourceBuffer.h
+++ b/src/AudioFileSourceBuffer.h
@@ -27,8 +27,8 @@
 class AudioFileSourceBuffer : public AudioFileSource
 {
   public:
-    AudioFileSourceBuffer(AudioFileSource *in, int bufferBytes);
-    AudioFileSourceBuffer(AudioFileSource *in, void *buffer, int bufferBytes); // Pre-allocated buffer by app
+    AudioFileSourceBuffer(AudioFileSource *in, uint32_t bufferBytes);
+    AudioFileSourceBuffer(AudioFileSource *in, void *buffer, uint32_t bufferBytes); // Pre-allocated buffer by app
     virtual ~AudioFileSourceBuffer() override;
     
     virtual uint32_t read(void *data, uint32_t len) override;
@@ -48,12 +48,12 @@ class AudioFileSourceBuffer : public AudioFileSource
 
   private:
     AudioFileSource *src;
-    uint16_t buffSize;
+    uint32_t buffSize;
     uint8_t *buffer;
     bool deallocateBuffer;
-    uint16_t writePtr;
-    uint16_t readPtr;
-    uint16_t length;
+    uint32_t writePtr;
+    uint32_t readPtr;
+    uint32_t length;
     bool filled;
 };