cleanups, memory savings

src/DirectoryNode.cpp

@@ -470,6 +470,11 @@ void DirectoryNode::buildFlatMP3List(std::vector<std::pair<DirectoryNode *, int>
     }
 }
 
+const size_t DirectoryNode::getNumOfFiles()
+{
+    return subdirectories.size();
+}
+
 DirectoryNode *DirectoryNode::advanceToNextMP3(const String *currentGlobal)
 {
     bool useFirst = false;
@@ -537,7 +542,6 @@ DirectoryNode *DirectoryNode::advanceToNextMP3(const String *currentGlobal)
 void DirectoryNode::streamDirectoryHTML(Print &out) const {
     if (name == "/") {
         out.println(F("<ul>"));
-        delay(0); // yield to WiFi/other tasks
     }
 
     if (name != "/") {
@@ -546,29 +550,24 @@ void DirectoryNode::streamDirectoryHTML(Print &out) const {
         out.print(F("\"><b>"));
         out.print(name);
         out.println(F("</b></li>"));
-        delay(0); // yield periodically while streaming
     }
 
+    delay(0);
+
     for (size_t i = 0; i < mp3Files.size(); i++) {
         out.print(F("<li data-id=\""));
         out.print(ids[i]);
         out.print(F("\">"));
         out.print(mp3Files[i]);
         out.println(F("</li>"));
-        if ((i & 0x0F) == 0) { // yield every ~16 items
-            delay(0);
-        }
     }
 
     for (DirectoryNode* child : subdirectories) {
-        delay(0); // yield before descending
         child->streamDirectoryHTML(out);
-        delay(0); // and after returning
     }
 
     if (name == "/") {
         out.println(F("</ul>"));
-        delay(0);
     }
 }
 

src/DirectoryNode.h

@@ -35,6 +35,8 @@ public:
   const std::vector<DirectoryNode*>& getSubdirectories() const;
   const std::vector<String>& getMP3Files() const;
 
+  const size_t getNumOfFiles();
+
   void setCurrentPlaying(const String* mp3File);
   const String* getCurrentPlaying() const;
   const uint16_t getCurrentPlayingId() const;

src/main.cpp

@@ -28,39 +28,6 @@
 
 
 
-
-/* Simple spinlock using older GCC sync builtins (no libatomic required).
-   sd_lock_acquire() will block (with a small delay) until the lock is free.
-   sd_lock_release() releases the lock. This is sufficient for short SD ops. */
-static inline void sd_lock_acquire()
-{
-  while (__sync_lock_test_and_set(&sd_lock_flag, 1))
-  {
-    delay(1);
-  }
-}
-
-static inline void sd_lock_release()
-{
-  __sync_lock_release(&sd_lock_flag);
-}
-
-volatile uint8_t dir_lock_flag = 0;
-/* Lightweight spinlock to guard directory tree access (rootNode) */
-static inline void dir_lock_acquire()
-{
-  while (__sync_lock_test_and_set(&dir_lock_flag, 1))
-  {
-    delay(1);
-  }
-}
-static inline void dir_lock_release()
-{
-  __sync_lock_release(&dir_lock_flag);
-}
-
-
-
 // webrequest_blockings is a simple watchdog counter that tracks how long at least one HTTP request has been “active” (not yet disconnected) according to the AsyncWebServer.
 int webrequest_blockings = 0;
 
@@ -248,9 +215,9 @@ void handleUpload(AsyncWebServerRequest *request, String filename, size_t index,
       logBuffer.clear();
 
       // Rebuild directory tree to include new file (guarded)
-      dir_lock_acquire();
+      sd_lock_acquire();
       rootNode.buildDirectoryTree("/");
-      dir_lock_release();
+      sd_lock_release();
 
       request->send(200, txt_plain, "Upload successful");
     }
@@ -275,9 +242,9 @@ void handleMoveFile(AsyncWebServerRequest *request)
     sd_lock_release();
     Serial.println("Moved file: " + from + " to " + to);
     // Rebuild directory tree to update file list (guarded)
-    dir_lock_acquire();
+    sd_lock_acquire();
     rootNode.buildDirectoryTree("/");
-    dir_lock_release();
+    sd_lock_release();
     request->send(200, txt_plain, F("File moved successfully."));
   }
   else
@@ -300,9 +267,9 @@ void handleDeleteFile(AsyncWebServerRequest *request)
     sd_lock_release();
     Serial.println("Deleted file: " + filename);
     // Rebuild directory tree to update file list (guarded)
-    dir_lock_acquire();
+    sd_lock_acquire();
     rootNode.buildDirectoryTree("/");
-    dir_lock_release();
+    sd_lock_release();
     request->send(200, txt_plain, "File deleted.");
   }
   else
@@ -430,14 +397,16 @@ void playSongByRFID(String id)
   auto it = rfid_map.find(id);
   if (it == rfid_map.end())
   {
-    Serial.println("Song for UID not found: " + id);
+    Serial.print(F("Song for UID not found: "));
+    Serial.println(id);
     return;
   }
 
   MappingEntry entry = it->second;
   if (entry.target.length() == 0)
   {
-    Serial.println("Empty mapping target for UID: " + id);
+    Serial.print(F("Empty mapping target for UID: "));
+    Serial.println(id);
     return;
   }
 
@@ -544,7 +513,7 @@ void playSongByRFID(String id)
     }
   }
 
-  Serial.print("Playing mapped target: ");
+  Serial.print(F("Playing mapped target: "));
   Serial.println(mp3File);
 
   deactivateRFID();
@@ -552,7 +521,8 @@ void playSongByRFID(String id)
 
   if (!playFile(mp3File.c_str()))
   {
-    Serial.println("Failed to play mapped file: " + mp3File);
+    Serial.print(F("Failed to play mapped file: "));
+    Serial.println( mp3File);
     currentNode = nullptr;
 
     return;
@@ -571,7 +541,7 @@ bool playFile(const char *filename, uint32_t resumeFilePos)
 {
   if (filename == nullptr || strlen(filename) == 0)
   {
-    Serial.println("filename empty.");
+    Serial.println(F("filename empty."));
     return false;
   }
   // Serialize access to SD when audio opens the file (short critical section)
@@ -690,7 +660,7 @@ boolean readSongProgress(const char *filename)
   data.trim();
   if (data.length() == 0)
   {
-    Serial.println("Progress file empty");
+    Serial.println(F("Progress file empty"));
     return false;
   }
 
@@ -701,7 +671,8 @@ boolean readSongProgress(const char *filename)
 
   if (parsed != 2)
   {
-    Serial.println("Failed to parse progress data: " + data);
+    Serial.print(F("Failed to parse progress data: "));
+    Serial.println(data);
     return false;
   }
 
@@ -1156,9 +1127,10 @@ void init_webserver() {
 server.on("/", HTTP_GET, [](AsyncWebServerRequest *request)
               {
                 webreq_enter();
-                request->onDisconnect([](){ webreq_exit(); });
+                request->onDisconnect([](){ webreq_exit(); sd_lock_release();});
                 deactivateRFID();
                 activateSD();
+                sd_lock_acquire();
                 String htmlPath = getSysDir(index_file);
                 if (SD.exists(htmlPath))
                 {
@@ -1186,15 +1158,15 @@ server.on("/", HTTP_GET, [](AsyncWebServerRequest *request)
     server.on("/style.css", HTTP_GET, [](AsyncWebServerRequest *request)
               {
                 webreq_enter();
-                request->onDisconnect([](){ webreq_exit(); });
+                request->onDisconnect([](){ webreq_exit(); sd_lock_release();});
                 deactivateRFID();
-                activateSD();                
+                activateSD();               
                 // Ensure SD is active and RFID is deactivated while serving files.
                 String cssPath = getSysDir(style_file);
                 if (SD.exists(cssPath))
                 {
                   uint32_t fsize = 0;
-                  {
+                  {                    
                     File f = SD.open(cssPath);
                     if (f) { fsize = f.size(); f.close(); }
                   }
@@ -1219,9 +1191,10 @@ server.on("/", HTTP_GET, [](AsyncWebServerRequest *request)
     server.on("/script.js", HTTP_GET, [](AsyncWebServerRequest *request)
               {
                 webreq_enter();
-                request->onDisconnect([](){ webreq_exit(); });
+                request->onDisconnect([](){ webreq_exit(); sd_lock_release();});
                 deactivateRFID();
                 activateSD();
+                sd_lock_acquire();
                 String jsPath = getSysDir(script_file);
                 if (SD.exists(jsPath))
                 {
@@ -1256,21 +1229,20 @@ server.on("/", HTTP_GET, [](AsyncWebServerRequest *request)
                 // Stream the response directly from the directory tree to avoid large temporary Strings
                 AsyncResponseStream* stream = request->beginResponseStream(txt_html_charset);
 #ifdef DEBUG                
-                Serial.printf("Serving /directory heap=%u webreq_cnt=%u\n", (unsigned)xPortGetFreeHeapSize(), (unsigned)webreq_cnt);
+                Serial.printf("Serving /directory heap=%u webreq_cnt=%u numOfFiles=%u\n", (unsigned)xPortGetFreeHeapSize(), (unsigned)webreq_cnt, rootNode.getNumOfFiles());
 #endif                
                 stream->addHeader(hdr_cache_control_key, hdr_cache_control_val);
                 stream->addHeader(hdr_connection_key, hdr_connection_val);
                 // Generate HTML directly into the stream under lock
-                dir_lock_acquire();
+                rootNode.streamDirectoryHTML(*stream);               
-                rootNode.streamDirectoryHTML(*stream);
-                dir_lock_release();
                 request->send(stream);
               });
 
     server.on("/mapping", HTTP_GET, [](AsyncWebServerRequest *request)
               {
                 webreq_enter();
-                request->onDisconnect([](){ webreq_exit(); });
+                request->onDisconnect([](){ webreq_exit(); sd_lock_release();});
+                sd_lock_acquire();
                 // Stream mapping to avoid Content-Length mismatches and reduce heap spikes
                 AsyncResponseStream* stream = request->beginResponseStream(txt_html_charset);
 #ifdef DEBUG                

src/main.h

@@ -34,6 +34,8 @@
 
 #define MAX_VOL 15
 
+//#define DEBUG TRUE
+
 File root;
 File mp3File;
 
@@ -125,6 +127,23 @@ void dump_byte_array(byte *buffer, byte bufferSize)
     }
 }
 
+/* Simple spinlock using older GCC sync builtins (no libatomic required).
+   sd_lock_acquire() will block (with a small delay) until the lock is free.
+   sd_lock_release() releases the lock. This is sufficient for short SD ops. */
+static inline void sd_lock_acquire()
+{
+  while (__sync_lock_test_and_set(&sd_lock_flag, 1))
+  {
+    delay(1);
+  }
+}
+
+static inline void sd_lock_release()
+{
+  __sync_lock_release(&sd_lock_flag);
+}
+
+
 String getRFIDString(byte uidByte[10])
 {
     String uidString = String(uidByte[0]) + " " + String(uidByte[1]) + " " +

web/script.js

@@ -326,7 +326,6 @@ function editMapping() {
 // Validate file before upload
 function validateFile(file) {
   var maxSize = 50 * 1024 * 1024; // 50MB limit
-  var allowedTypes = ['audio/mpeg', 'audio/wav'];
   var allowedExtensions = ['.mp3'];
   
   if (file.size > maxSize) {
@@ -499,92 +498,3 @@ function deleteFileOnServer() {
   xhr.send();
 }
 
-/* Ensure the site stylesheet loads reliably — retry loader if necessary
-   Improved detection: verify a computed style from CSS is applied (safer than just checking stylesheet href).
-   Retries with exponential backoff and deduplicates link tags we add. */
-(function ensureCssLoaded(){
-  var retries = 0;
-  var maxRetries = 6;
-
-  // Check a computed style that the stylesheet defines.
-  // .status color in CSS is --muted: #6b7280 -> rgb(107, 114, 128)
-  function isStyleApplied() {
-    var el = document.querySelector('.status') || document.querySelector('.topbar');
-    if (!el) return false;
-    try {
-      var color = getComputedStyle(el).color;
-      // Expect "rgb(107, 114, 128)" when CSS is applied
-      if (!color) return false;
-      // Loose check for the three numeric components to be present
-      return color.indexOf('107') !== -1 && color.indexOf('114') !== -1 && color.indexOf('128') !== -1;
-    } catch (e) {
-      return false;
-    }
-  }
-
-  function removeOldRetryLinks() {
-    var links = Array.prototype.slice.call(document.querySelectorAll('link[data-retry-css]'));
-    links.forEach(function(l){ l.parentNode.removeChild(l); });
-  }
-
-  function tryLoad() {
-    if (isStyleApplied()) {
-      console.log('style.css appears applied');
-      return;
-    }
-    if (retries >= maxRetries) {
-      console.warn('style.css failed to apply after ' + retries + ' attempts');
-      return;
-    }
-    retries++;
-    // Remove previous retry-inserted links to avoid piling them up
-    removeOldRetryLinks();
-
-    var link = document.createElement('link');
-    link.rel = 'stylesheet';
-    link.setAttribute('data-retry-css', '1');
-    // cache-busting query to force a fresh fetch when retrying
-    link.href = 'style.css?cb=' + Date.now();
-    var timeout = 800 + retries * 300; // increasing timeout per attempt
-
-    var done = false;
-    function success() {
-      if (done) return;
-      done = true;
-      // Give browser a short moment to apply rules
-      setTimeout(function(){
-        if (isStyleApplied()) {
-          console.log('style.css loaded and applied (attempt ' + retries + ')');
-        } else {
-          console.warn('style.css loaded but styles not applied — retrying...');
-          setTimeout(tryLoad, timeout);
-        }
-      }, 200);
-    }
-
-    link.onload = success;
-    link.onerror = function() {
-      if (done) return;
-      done = true;
-      console.warn('style.css load error (attempt ' + retries + '), retrying...');
-      setTimeout(tryLoad, timeout);
-    };
-
-    // Append link to head
-    document.head.appendChild(link);
-
-    // Safety check: if onload/onerror doesn't fire, verify computed style after timeout
-    setTimeout(function(){
-      if (done) return;
-      if (isStyleApplied()) {
-        console.log('style.css appears applied (delayed check)');
-      } else {
-        console.warn('style.css still not applied after timeout (attempt ' + retries + '), retrying...');
-        setTimeout(tryLoad, timeout);
-      }
-    }, timeout + 300);
-  }
-
-  // Start after a short delay to let the browser initiate initial requests
-  setTimeout(tryLoad, 150);
-})();