diff -r 21274e5950af -r a1f4cb076d2f src/server/util/io.h
--- a/src/server/util/io.h	Tue Aug 13 22:14:32 2019 +0200
+++ b/src/server/util/io.h	Sat Sep 24 16:26:10 2022 +0200
@@ -89,13 +89,59 @@
 #endif
 };
 
+#define HTTP_STREAM_CBUF_SIZE 16
 struct HttpStream {
     IOStream st;
     IOStream *fd;
+    
+    /*
+     * content-length or current chunk size
+     */
     uint64_t max_read;
+    /*
+     * total bytes read (with content-length) or bytes read of current chunk
+     */
     uint64_t read;
+    /*
+     * total bytes read with chunked transfer encoding
+     */
+    uint64_t read_total;
+    /*
+     * read buffer (used only with chunked transfer encoding)
+     */
+    char     *readbuf;
+    /*
+     * readbuf allocated size
+     */
+    size_t   bufsize;
+    /*
+     * number of bytes currently stored in readbuf
+     */
+    int      *buflen;
+    /*
+     * current position in the read buffer
+     */
+    int      *bufpos;
+    /*
+     * current chunk_buf position
+     */
+    int      chunk_buf_pos;
+    /*
+     * buffer used only for parsing chunk headers
+     */
+    char     chunk_buf[HTTP_STREAM_CBUF_SIZE];
+    /*
+     * chunked transfer encoding for write enabled?
+     */
     WSBool   chunked_enc;
-    WSBool   buffered;
+    /*
+     * end of file indicator (read)
+     */
+    WSBool   read_eof;
+    /*
+     * end of file indicator (write)
+     */
+    WSBool write_eof;
 };
 
 typedef struct SSLStream {
@@ -120,9 +166,15 @@
 /* http stream */
 IOStream* httpstream_new(pool_handle_t *pool, IOStream *fd);
 
+int httpstream_enable_chunked_read(IOStream *st, char *buffer, size_t bufsize, int *cursize, int *pos);
+int httpstream_enable_chunked_write(IOStream *st);
+int httpstream_set_max_read(IOStream *st, int64_t maxread);
+WSBool httpstream_eof(IOStream *st);
+
 ssize_t net_http_write(HttpStream *st, void *buf, size_t nbytes);
 ssize_t net_http_writev(HttpStream *st, struct iovec *iovec, int iovcnt);
 ssize_t net_http_read(HttpStream *st, void *buf, size_t nbytes);
+ssize_t net_http_read_chunked(HttpStream *st, void *buf, size_t nbytes);
 ssize_t net_http_sendfile(HttpStream *st, sendfiledata *sfd);
 void    net_http_close(HttpStream *st);
 void    net_http_finish(HttpStream *st);