From 5a8f5b833093961096c7787ed46a18b4d69b554c Mon Sep 17 00:00:00 2001
From: Michael Sevakis <jethead71@rockbox.org>
Date: Mon, 9 May 2011 21:19:11 +0000
Subject: [PATCH] Provide a reasonable fix for FS#12093 - Playback hanging
 after codec/playback rework. Also, get rid of an impossible buffering case
 (BUF_USED is always less than buffer_len) and remove a buffering API that is
 not used anywhere and shouldn't be needed (plugin API has to be
 incompatible).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29849 a1c6a512-1295-4272-9138-f99709370657
---
 apps/buffering.c | 27 ++++++++++++---------------
 apps/buffering.h |  2 --
 apps/plugin.c    |  1 -
 apps/plugin.h    |  5 ++---
 4 files changed, 14 insertions(+), 21 deletions(-)

diff --git a/apps/buffering.c b/apps/buffering.c
index a130a787ff..c47564b7e1 100644
--- a/apps/buffering.c
+++ b/apps/buffering.c
@@ -1339,7 +1339,8 @@ static struct memory_handle *prep_bufdata(int handle_id, size_t *size,
 
     if (h->filerem > 0 && avail < realsize) {
         /* Data isn't ready. Request buffering */
-        buf_request_buffer_handle(handle_id);
+        LOGFQUEUE("buffering >| Q_START_FILL %d",handle_id);
+        queue_send(&buffering_queue, Q_START_FILL, handle_id);
         /* Wait for the data to be ready */
         do
         {
@@ -1486,7 +1487,6 @@ SECONDARY EXPORTED FUNCTIONS
 ============================
 
 buf_handle_offset
-buf_request_buffer_handle
 buf_set_base_handle
 buf_handle_data_type
 buf_is_handle
@@ -1510,12 +1510,6 @@ ssize_t buf_handle_offset(int handle_id)
     return h->offset;
 }
 
-void buf_request_buffer_handle(int handle_id)
-{
-    LOGFQUEUE("buffering >| Q_START_FILL %d",handle_id);
-    queue_send(&buffering_queue, Q_START_FILL, handle_id);
-}
-
 void buf_set_base_handle(int handle_id)
 {
     mutex_lock(&llist_mutex);
@@ -1642,7 +1636,15 @@ static void NORETURN_ATTR buffering_thread(void)
                 LOGFQUEUE("buffering < Q_START_FILL %d", (int)ev.data);
                 shrink_buffer();
                 queue_reply(&buffering_queue, 1);
-                filling |= buffer_handle((int)ev.data, 0);
+                if (buffer_handle((int)ev.data, 0)) {
+                    filling = true;
+                }
+                else if (num_handles > 0 && conf_watermark > 0) {
+                    update_data_counters(NULL);
+                    if (data_counters.useful >= BUF_WATERMARK) {
+                        send_event(BUFFER_EVENT_BUFFER_LOW, NULL);
+                    }
+                }
                 break;
 
             case Q_BUFFER_HANDLE:
@@ -1699,12 +1701,7 @@ static void NORETURN_ATTR buffering_thread(void)
 #endif
 
         if (filling) {
-            if (data_counters.remaining > 0 && BUF_USED < buffer_len) {
-                filling = fill_buffer();
-            }
-            else if (data_counters.remaining == 0) {
-                filling = false;
-            }
+            filling = data_counters.remaining > 0 ? fill_buffer() : false;
         } else if (ev.id == SYS_TIMEOUT) {
             if (data_counters.useful < BUF_WATERMARK) {
                 /* The buffer is low and we're idle, just watching the levels
diff --git a/apps/buffering.h b/apps/buffering.h
index 2e4cfd3968..ee3e7c9053 100644
--- a/apps/buffering.h
+++ b/apps/buffering.h
@@ -95,7 +95,6 @@ ssize_t bufcuttail(int handle_id, size_t size);
  * buf_is_handle: is the handle valid?
  * buf_pin_handle: Disallow/allow handle movement. Handle may still be removed.
  * buf_handle_offset: Get the offset of the first buffered byte from the file
- * buf_request_buffer_handle: Request buffering of a handle
  * buf_set_base_handle: Tell the buffering thread which handle is currently read
  * buf_length: Total size of ringbuffer
  * buf_used: Total amount of buffer space used (including allocated space)
@@ -106,7 +105,6 @@ enum data_type buf_handle_data_type(int handle_id);
 ssize_t buf_handle_remaining(int handle_id);
 bool buf_is_handle(int handle_id);
 ssize_t buf_handle_offset(int handle_id);
-void buf_request_buffer_handle(int handle_id);
 void buf_set_base_handle(int handle_id);
 size_t buf_length(void);
 size_t buf_used(void);
diff --git a/apps/plugin.c b/apps/plugin.c
index bb326d937b..d9f7c4e24c 100644
--- a/apps/plugin.c
+++ b/apps/plugin.c
@@ -747,7 +747,6 @@ static const struct plugin_api rockbox_api = {
     bufcuttail,
 
     buf_handle_offset,
-    buf_request_buffer_handle,
     buf_set_base_handle,
     buf_used,
 #endif
diff --git a/apps/plugin.h b/apps/plugin.h
index cdf34e28b1..f15c626667 100644
--- a/apps/plugin.h
+++ b/apps/plugin.h
@@ -145,12 +145,12 @@ void* plugin_get_buffer(size_t *buffer_size);
 #define PLUGIN_MAGIC 0x526F634B /* RocK */
 
 /* increase this every time the api struct changes */
-#define PLUGIN_API_VERSION 204
+#define PLUGIN_API_VERSION 205
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
    new function which are "waiting" at the end of the function table) */
-#define PLUGIN_MIN_API_VERSION 204
+#define PLUGIN_MIN_API_VERSION 205
 
 /* plugin return codes */
 /* internal returns start at 0x100 to make exit(1..255) work */
@@ -873,7 +873,6 @@ struct plugin_api {
     ssize_t (*bufcuttail)(int handle_id, size_t size);
 
     ssize_t (*buf_handle_offset)(int handle_id);
-    void (*buf_request_buffer_handle)(int handle_id);
     void (*buf_set_base_handle)(int handle_id);
     size_t (*buf_used)(void);
 #endif