Revert "AsyncAbstractResponse: Fix packet buffer lifetime"

This reverts commit ca1262c.

src/WebResponseImpl.h

@@ -27,7 +27,6 @@
 #undef max
 #endif
 #include <vector>
-#include <default_init_allocator.h>
 // It is possible to restore these defines, but one can use _min and _max instead. Or std::min, std::max.
 
 class AsyncBasicResponse: public AsyncWebServerResponse {
@@ -47,8 +46,7 @@ class AsyncAbstractResponse: public AsyncWebServerResponse {
     // This is inefficient with vector, but if we use some other container, 
     // we won't be able to access it as contiguous array of bytes when reading from it,
     // so by gaining performance in one place, we'll lose it in another.
-    std::vector<uint8_t, default_init_allocator<uint8_t>> _pkt_buf;
-    std::vector<uint8_t, default_init_allocator<uint8_t>> _cache;
+    std::vector<uint8_t> _cache;
     size_t _readDataFromCacheOrContent(uint8_t* data, const size_t len);
     size_t _fillBufferAndProcessTemplates(uint8_t* buf, size_t maxLen);
   protected:

src/WebResponses.cpp

@@ -321,11 +321,11 @@ size_t AsyncAbstractResponse::_ack(AsyncWebServerRequest *request, size_t len, u
       outLen = ((_contentLength - _sentLength) > space)?space:(_contentLength - _sentLength);
     }
 
-    if (_pkt_buf.size() < (outLen + headLen)) {
-      // Make it bigger without preserving the existing contents
-      _pkt_buf = decltype(_pkt_buf) ( (size_t) (outLen+headLen) );
+    uint8_t *buf = (uint8_t *)malloc(outLen+headLen);
+    if (!buf) {
+      // os_printf("_ack malloc %d failed\n", outLen+headLen);
+      return 0;
     }
-    uint8_t *buf = _pkt_buf.data();
 
     if(headLen){
       memcpy(buf, _head.c_str(), _head.length());
@@ -338,6 +338,7 @@ size_t AsyncAbstractResponse::_ack(AsyncWebServerRequest *request, size_t len, u
       // See RFC2616 sections 2, 3.6.1.
       readLen = _fillBufferAndProcessTemplates(buf+headLen+6, outLen - 8);
       if(readLen == RESPONSE_TRY_AGAIN){
+          free(buf);
           return 0;
       }
       outLen = sprintf((char*)buf+headLen, "%x", readLen) + headLen;
@@ -350,6 +351,7 @@ size_t AsyncAbstractResponse::_ack(AsyncWebServerRequest *request, size_t len, u
     } else {
       readLen = _fillBufferAndProcessTemplates(buf+headLen, outLen);
       if(readLen == RESPONSE_TRY_AGAIN){
+          free(buf);
           return 0;
       }
       outLen = readLen + headLen;
@@ -369,6 +371,8 @@ size_t AsyncAbstractResponse::_ack(AsyncWebServerRequest *request, size_t len, u
         _sentLength += outLen - headLen;
     }
 
+    free(buf);
+
     if((_chunked && readLen == 0) || (!_sendContentLength && outLen == 0) || (!_chunked && _sentLength == _contentLength)){
       _state = RESPONSE_WAIT_ACK;
     }