Support Safari streaming behaviour (#2142)

As explained in https://stackoverflow.com/a/79309100

Author: rsdy

src/AudioTools/CoreAudio/AudioHttp/AudioServer.h

@@ -130,10 +130,17 @@ class AudioServerT {
  if (callback == nullptr) {
  LOGD("copy data...");
  if (converter_ptr == nullptr) {
- copier.copy();
+ sent += copier.copy();
  } else {
- copier.copy(*converter_ptr);
+ sent += copier.copy(*converter_ptr);
  }
+
+ if (max_bytes > 0 && sent >= max_bytes) {
+ LOGI("range exhausted...");
+ client_obj.stop();
+ active = false;
+ }
+
  // if we limit the size of the WAV the encoder gets automatically
  // closed when all has been sent
  if (!client_obj) {
@@ -176,6 +183,8 @@ class AudioServerT {
  Client client_obj;
  char *password = nullptr;
  char *network = nullptr;
+ size_t max_bytes = 0;
+ size_t sent = 0;
 
  // Content
  const char *content_type = nullptr;
@@ -211,10 +220,17 @@ class AudioServerT {
 
  virtual void sendReplyHeader() {
  TRACED();
+
  // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
  // and a content-type so the client knows what's coming, then a blank line:
- client_obj.println("HTTP/1.1 200 OK");
- LOGI("Reply: HTTP/1.1 200 OK");
+ char *response;
+ if (max_bytes > 0) {
+response = "HTTP/1.1 206 OK";
+ } else {
+response = "HTTP/1.1 200 OK";
+ }
+ client_obj.println(response);
+ LOGI(response);
  if (content_type != nullptr) {
  client_obj.print("Content-type:");
  client_obj.println(content_type);
@@ -250,18 +266,29 @@ class AudioServerT {
  LOGI("New Client:"); // print a message out the serial port
  String currentLine =
  ""; // make a String to hold incoming data from the client
+ long firstbyte = 0;
+ long lastbyte = 0;
  while (client_obj.connected()) { // loop while the client's connected
  if (client_obj
  .available()) { // if there's bytes to read from the client,
  char c = client_obj.read(); // read a byte, then
  if (c == '\n') { // if the byte is a newline character
  LOGI("Request: %s", currentLine.c_str());
+ if (currentLine.startsWith(String("Range: bytes="))) {
+int minuspos = currentLine.indexOf('-', 13);
+
+// toInt returns 0 if it's an invalid conversion, so it's "safe"
+firstbyte = currentLine.substring(13, minuspos).toInt();
+lastbyte = currentLine.substring(minuspos + 1).toInt();
+ }
  // if the current line is blank, you got two newline characters in a
  // row. that's the end of the client HTTP request, so send a
  // response:
  if (currentLine.length() == 0) {
  sendReplyHeader();
  sendReplyContent();
+ max_bytes = lastbyte - firstbyte;
+ sent = 0;
  // break out of the while loop:
  break;
  } else { // if you got a newline, then clear currentLine: