[vlc-commits] chromecast: don't drop data when serving multiple clients

[Thomas Guillem]

vlc/vlc-3.0 | branch: master | Thomas Guillem <thomas at gllm.fr> | Tue Feb 20 17:48:15 2018 +0100| [7fac2a72369af83a85f1c25af9126f0f2dcff2d6] | committer: Thomas Guillem

chromecast: don't drop data when serving multiple clients

When doing a lot a load requests, we can serve data to a client that will be
closed (the close request is already sent). In that case, we should also serve
data used by the old client to the new one.

(cherry picked from commit 9339ff4b61a16e2edd5baa42b6a0207e581fd3be)
Signed-off-by: Thomas Guillem <thomas at gllm.fr>

> http://git.videolan.org/gitweb.cgi/vlc/vlc-3.0.git/?a=commit;h=7fac2a72369af83a85f1c25af9126f0f2dcff2d6
---

 modules/stream_out/chromecast/cast.cpp | 51 ++++++++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/modules/stream_out/chromecast/cast.cpp b/modules/stream_out/chromecast/cast.cpp
index 6015f3f03f..2b683014c3 100644
--- a/modules/stream_out/chromecast/cast.cpp
+++ b/modules/stream_out/chromecast/cast.cpp
@@ -70,6 +70,9 @@ private:
     httpd_client_t    *m_client;
     vlc_fifo_t        *m_fifo;
     block_t           *m_header;
+    block_t           *m_copy_chain;
+    block_t           **m_copy_last;
+    size_t             m_copy_size;
     bool               m_eof;
     std::string        m_mime;
 };
@@ -228,6 +231,7 @@ static const char *const conversion_quality_list_text[] = {
 #define HTTPD_BUFFER_PACE INT64_C(2 * 1024 * 1024) /* 2 MB */
 /* Fifo size after we drop packets (should not happen) */
 #define HTTPD_BUFFER_MAX INT64_C(32 * 1024 * 1024) /* 32 MB */
+#define HTTPD_BUFFER_COPY_MAX INT64_C(10 * 1024 * 1024) /* 10 MB */
 
 vlc_module_begin ()
 
@@ -365,6 +369,7 @@ sout_access_out_sys_t::sout_access_out_sys_t(httpd_host_t *httpd_host,
     : m_intf(intf)
     , m_client(NULL)
     , m_header(NULL)
+    , m_copy_chain(NULL)
     , m_eof(true)
 {
     m_fifo = block_FifoNew();
@@ -378,7 +383,7 @@ sout_access_out_sys_t::sout_access_out_sys_t(httpd_host_t *httpd_host,
     }
     httpd_UrlCatch(m_url, HTTPD_MSG_GET, httpd_url_cb,
                    (httpd_callback_sys_t*)this);
-
+    initCopy();
 }
 
 sout_access_out_sys_t::~sout_access_out_sys_t()
@@ -396,6 +401,44 @@ void sout_access_out_sys_t::clearUnlocked()
         m_header = NULL;
     }
     m_eof = true;
+    initCopy();
+}
+
+void sout_access_out_sys_t::initCopy()
+{
+    block_ChainRelease(m_copy_chain);
+    m_copy_chain = NULL;
+    m_copy_last = &m_copy_chain;
+    m_copy_size = 0;
+}
+
+void sout_access_out_sys_t::putCopy(block_t *p_block)
+{
+    while (m_copy_size >= HTTPD_BUFFER_COPY_MAX)
+    {
+        assert(m_copy_chain);
+        block_t *copy = m_copy_chain;
+        m_copy_chain = copy->p_next;
+        m_copy_size -= copy->i_buffer;
+        block_Release(copy);
+    }
+    if (!m_copy_chain)
+    {
+        assert(m_copy_size == 0);
+        m_copy_last = &m_copy_chain;
+    }
+    block_ChainLastAppend(&m_copy_last, p_block);
+    m_copy_size += p_block->i_buffer;
+}
+
+void sout_access_out_sys_t::restoreCopy()
+{
+    if (m_copy_chain)
+    {
+        fifo_put_back(m_copy_chain);
+        m_copy_chain = NULL;
+        initCopy();
+    }
 }
 
 void sout_access_out_sys_t::clear()
@@ -445,6 +488,10 @@ int sout_access_out_sys_t::url_cb(httpd_client_t *cl, httpd_message_t *answer,
 
     if (!answer->i_body_offset)
     {
+        /* When doing a lot a load requests, we can serve data to a client that
+         * will be closed (the close request is already sent). In that case, we
+         * should also serve data used by the old client to the new one. */
+        restoreCopy();
         m_client = cl;
     }
 
@@ -494,7 +541,7 @@ int sout_access_out_sys_t::url_cb(httpd_client_t *cl, httpd_message_t *answer,
         }
 
         if (p_block != m_header)
-            block_Release(p_block);
+            putCopy(p_block);
     }
     else
         httpd_MsgAdd(answer, "Connection", "close");