Abort print on media removal (MarlinFirmware#20200)

Marlin/src/sd/cardreader.cpp

@@ -450,15 +450,28 @@ void CardReader::manage_media() {
     DEBUG_ECHOLNPGM("SD: No UI Detected.");
 }
 
+/**
+ * "Release" the media by clearing the 'mounted' flag.
+ * Used by M22, "Release Media", manage_media.
+ */
 void CardReader::release() {
-  endFilePrint();
+  // Card removed while printing? Abort!
+  if (IS_SD_PRINTING())
+    card.flag.abort_sd_printing = true;
+  else
+    endFilePrint();
+
   flag.mounted = false;
   flag.workDirIsRoot = true;
   #if ALL(SDCARD_SORT_ALPHA, SDSORT_USES_RAM, SDSORT_CACHE_NAMES)
     nrFiles = 0;
   #endif
 }
 
+/**
+ * Open a G-code file and set Marlin to start processing it.
+ * Enqueues M23 and M24 commands to initiate a media print.
+ */
 void CardReader::openAndPrintFile(const char *name) {
   char cmd[4 + strlen(name) + 1]; // Room for "M23 ", filename, and null
   extern const char M23_STR[];
@@ -468,13 +481,22 @@ void CardReader::openAndPrintFile(const char *name) {
   queue.enqueue_now_P(M24_STR);
 }
 
+/**
+ * Start or resume a media print by setting the sdprinting flag.
+ * The file browser pre-sort is also purged to free up memory,
+ * since you cannot browse files during active printing.
+ * Used by M24 and anywhere Start / Resume applies.
+ */
 void CardReader::startFileprint() {
   if (isMounted()) {
     flag.sdprinting = true;
     TERN_(SD_RESORT, flush_presort());
   }
 }
 
+//
+// Run tasks upon finishing or aborting a file print.
+//
 void CardReader::endFilePrint(TERN_(SD_RESORT, const bool re_sort/*=false*/)) {
   TERN_(ADVANCED_PAUSE_FEATURE, did_pause_print = 0);
   TERN_(DWIN_CREALITY_LCD, HMI_flag.print_finish = flag.sdprinting);