fix: use RAII render lock everywhere (#916)

Follow-up to
https://github.com/crosspoint-reader/crosspoint-reader/pull/774

---

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

* **Refactor**
* Modernized internal synchronization mechanisms across multiple
components to improve code reliability and maintainability. All
functionality remains unchanged.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

src/activities/network/WifiSelectionActivity.cpp

@@ -244,9 +244,10 @@ void WifiSelectionActivity::checkConnectionStatus() {
 
     // Save this as the last connected network - SD card operations need lock as
     // we use SPI for both
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       WIFI_STORE.setLastConnectedSsid(selectedSSID);
-    xSemaphoreGive(renderingMutex);
+    }
 
     // If we entered a new password, ask if user wants to save it
     // Otherwise, immediately complete so parent can start web server

src/activities/reader/EpubReaderActivity.cpp

@@ -296,11 +296,12 @@ void EpubReaderActivity::loop() {
 
   if (skipChapter) {
     // We don't want to delete the section mid-render, so grab the semaphore
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       nextPageNumber = 0;
       currentSpineIndex = nextTriggered ? currentSpineIndex + 1 : currentSpineIndex - 1;
       section.reset();
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
@@ -316,11 +317,12 @@ void EpubReaderActivity::loop() {
       section->currentPage--;
     } else {
       // We don't want to delete the section mid-render, so grab the semaphore
-      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      {
+        RenderLock lock(*this);
         nextPageNumber = UINT16_MAX;
         currentSpineIndex--;
         section.reset();
-      xSemaphoreGive(renderingMutex);
+      }
     }
     requestUpdate();
   } else {
@@ -328,11 +330,12 @@ void EpubReaderActivity::loop() {
       section->currentPage++;
     } else {
       // We don't want to delete the section mid-render, so grab the semaphore
-      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      {
+        RenderLock lock(*this);
         nextPageNumber = 0;
         currentSpineIndex++;
         section.reset();
-      xSemaphoreGive(renderingMutex);
+      }
     }
     requestUpdate();
   }
@@ -402,12 +405,13 @@ void EpubReaderActivity::jumpToPercent(int percent) {
   }
 
   // Reset state so render() reloads and repositions on the target spine.
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     currentSpineIndex = targetSpineIndex;
     nextPageNumber = 0;
     pendingPercentJump = true;
     section.reset();
-  xSemaphoreGive(renderingMutex);
+  }
 }
 
 void EpubReaderActivity::onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction action) {
@@ -706,7 +710,8 @@ void EpubReaderActivity::onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction
       break;
     }
     case EpubReaderMenuActivity::MenuAction::DELETE_CACHE: {
-      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      {
+        RenderLock lock(*this);
         if (epub) {
           // 2. BACKUP: Read current progress
           // We use the current variables that track our position
@@ -726,7 +731,7 @@ void EpubReaderActivity::onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction
           // 5. Remove from recent books so the home screen doesn't show a stale/placeholder cover
           RECENT_BOOKS.removeBook(epub->getPath());
         }
-      xSemaphoreGive(renderingMutex);
+      }
       // Defer go home to avoid race condition with display task
       pendingGoHome = true;
       break;
@@ -768,7 +773,8 @@ void EpubReaderActivity::applyOrientation(const uint8_t orientation) {
   }
 
   // Preserve current reading position so we can restore after reflow.
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     if (section) {
       cachedSpineIndex = currentSpineIndex;
       cachedChapterTotalPageCount = section->pageCount;
@@ -784,7 +790,7 @@ void EpubReaderActivity::applyOrientation(const uint8_t orientation) {
 
     // Reset section to force re-layout in the new orientation.
     section.reset();
-  xSemaphoreGive(renderingMutex);
+  }
 }
 
 // TODO: Failure handling

src/activities/reader/KOReaderSyncActivity.cpp

@@ -51,18 +51,20 @@ void KOReaderSyncActivity::onWifiSelectionComplete(const bool success) {
 
   LOG_DBG("KOSync", "WiFi connected, starting sync");
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = SYNCING;
     statusMessage = "Syncing time...";
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 
   // Sync time with NTP before making API requests
   syncTimeWithNTP();
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     statusMessage = "Calculating document hash...";
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 
   performSync();
@@ -76,19 +78,21 @@ void KOReaderSyncActivity::performSync() {
     documentHash = KOReaderDocumentId::calculate(epubPath);
   }
   if (documentHash.empty()) {
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = SYNC_FAILED;
       statusMessage = "Failed to calculate document hash";
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
   LOG_DBG("KOSync", "Document hash: %s", documentHash.c_str());
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     statusMessage = "Fetching remote progress...";
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdateAndWait();
 
   // Fetch remote progress
@@ -96,19 +100,21 @@ void KOReaderSyncActivity::performSync() {
 
   if (result == KOReaderSyncClient::NOT_FOUND) {
     // No remote progress - offer to upload
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = NO_REMOTE_PROGRESS;
       hasRemoteProgress = false;
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
   if (result != KOReaderSyncClient::OK) {
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = SYNC_FAILED;
       statusMessage = KOReaderSyncClient::errorString(result);
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
@@ -122,18 +128,20 @@ void KOReaderSyncActivity::performSync() {
   CrossPointPosition localPos = {currentSpineIndex, currentPage, totalPagesInSpine};
   localProgress = ProgressMapper::toKOReader(epub, localPos);
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = SHOWING_RESULT;
     selectedOption = 0;  // Default to "Apply"
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 }
 
 void KOReaderSyncActivity::performUpload() {
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = UPLOADING;
     statusMessage = "Uploading progress...";
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
   requestUpdateAndWait();
 
@@ -149,17 +157,19 @@ void KOReaderSyncActivity::performUpload() {
   const auto result = KOReaderSyncClient::updateProgress(progress);
 
   if (result != KOReaderSyncClient::OK) {
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = SYNC_FAILED;
       statusMessage = KOReaderSyncClient::errorString(result);
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = UPLOAD_COMPLETE;
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 }
 
@@ -190,9 +200,10 @@ void KOReaderSyncActivity::onEnter() {
           auto* self = static_cast<KOReaderSyncActivity*>(param);
           // Sync time first
           syncTimeWithNTP();
-          xSemaphoreTake(self->renderingMutex, portMAX_DELAY);
+          {
+            RenderLock lock(*self);
             self->statusMessage = "Calculating document hash...";
-          xSemaphoreGive(self->renderingMutex);
+          }
           self->requestUpdate();
           self->performSync();
           vTaskDelete(nullptr);

src/activities/settings/ClearCacheActivity.cpp

@@ -118,9 +118,10 @@ void ClearCacheActivity::loop() {
   if (state == WARNING) {
     if (mappedInput.wasPressed(MappedInputManager::Button::Confirm)) {
       LOG_DBG("CLEAR_CACHE", "User confirmed, starting cache clear");
-      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      {
+        RenderLock lock(*this);
         state = CLEARING;
-      xSemaphoreGive(renderingMutex);
+      }
       requestUpdateAndWait();
 
       clearCache();

src/activities/settings/KOReaderAuthActivity.cpp

@@ -14,18 +14,20 @@ void KOReaderAuthActivity::onWifiSelectionComplete(const bool success) {
   exitActivity();
 
   if (!success) {
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = FAILED;
       errorMessage = "WiFi connection failed";
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = AUTHENTICATING;
     statusMessage = "Authenticating...";
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 
   performAuthentication();
@@ -34,7 +36,8 @@ void KOReaderAuthActivity::onWifiSelectionComplete(const bool success) {
 void KOReaderAuthActivity::performAuthentication() {
   const auto result = KOReaderSyncClient::authenticate();
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     if (result == KOReaderSyncClient::OK) {
       state = SUCCESS;
       statusMessage = "Successfully authenticated!";
@@ -42,7 +45,7 @@ void KOReaderAuthActivity::performAuthentication() {
       state = FAILED;
       errorMessage = KOReaderSyncClient::errorString(result);
     }
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 }
 

src/activities/settings/KOReaderSettingsActivity.cpp

@@ -121,7 +121,6 @@ void KOReaderSettingsActivity::handleSelection() {
     // Authenticate
     if (!KOREADER_STORE.hasCredentials()) {
       // Can't authenticate without credentials - just show message briefly
-      xSemaphoreGive(renderingMutex);
       return;
     }
     exitActivity();

src/activities/settings/OtaUpdateActivity.cpp

@@ -20,33 +20,37 @@ void OtaUpdateActivity::onWifiSelectionComplete(const bool success) {
 
   LOG_DBG("OTA", "WiFi connected, checking for update");
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = CHECKING_FOR_UPDATE;
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdateAndWait();
 
   const auto res = updater.checkForUpdate();
   if (res != OtaUpdater::OK) {
     LOG_DBG("OTA", "Update check failed: %d", res);
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = FAILED;
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
   if (!updater.isUpdateNewer()) {
     LOG_DBG("OTA", "No new update available");
-    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    {
+      RenderLock lock(*this);
       state = NO_UPDATE;
-    xSemaphoreGive(renderingMutex);
+    }
     requestUpdate();
     return;
   }
 
-  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  {
+    RenderLock lock(*this);
     state = WAITING_CONFIRMATION;
-  xSemaphoreGive(renderingMutex);
+  }
   requestUpdate();
 }