playback,talk: Share audiobuffer via core_alloc_maximum().

This fixes the radioart crash that was the result of buffering.c working
on a freed buffer at the same time as buflib (radioart uses buffering.c for the
images). With this change the buffer is owned by buflib exclusively so this
cannot happen.

As a result, audio_get_buffer() doesn't exist anymore. Callers should call
core_alloc_maximum() directly. This buffer needs to be protected as usual
against movement if necessary (previously it was not protected at all which
cased the radioart crash), To get most of it they can adjust the willingness of
the talk engine to give its buffer away (at the expense of disabling voice
interface) with the new talk_buffer_set_policy() function.

Change-Id: I52123012208d04967876a304451d634e2bef3a33

2 files changed, 19 insertions, 11 deletions

diff --git a/apps/recorder/pcm_record.c b/apps/recorder/pcm_record.c
index 2170e473bc..799c733948 100644
--- a/apps/recorder/pcm_record.c
+++ b/apps/recorder/pcm_record.c
@@ -24,6 +24,7 @@
 #include "config.h"
 #include "system.h"
 #include "kernel.h"
+#include "panic.h"
 #include "string-extra.h"
 #include "pcm_record.h"
 #include "codecs.h"
@@ -40,6 +41,8 @@
 #include "spdif.h"
 #endif
 #include "audio_thread.h"
+#include "core_alloc.h"
+#include "talk.h"
 
 /* Macros to enable logf for queues
    logging on SYS_TIMEOUT can be disabled */
@@ -1402,11 +1405,22 @@ static void tally_prerecord_data(void)
 
 /** Event handlers for recording thread **/
 
+static int pcmrec_handle;
 /* Q_AUDIO_INIT_RECORDING */
 static void on_init_recording(void)
 {
     send_event(RECORDING_EVENT_START, NULL);
-    rec_buffer = audio_get_buffer(true, &rec_buffer_size);
+    /* dummy ops with no callbacks, needed because by
+     * default buflib buffers can be moved around which must be avoided
+     * FIXME: This buffer should play nicer and be shrinkable/movable */
+    static struct buflib_callbacks dummy_ops;
+    talk_buffer_set_policy(TALK_BUFFER_LOOSE);
+    pcmrec_handle = core_alloc_maximum("pcmrec", &rec_buffer_size, &dummy_ops);
+    if (pcmrec_handle)
+    /* someone is abusing core_alloc_maximum(). Fix this evil guy instead of
+     * trying to handle OOM without hope */
+        panicf("%s(): OOM\n", __func__);
+    rec_buffer = core_get_data(pcmrec_handle);
     init_rec_buffers();
     init_state();
     pcm_init_recording();
@@ -1430,6 +1444,10 @@ static void on_close_recording(void)
     audio_set_output_source(AUDIO_SRC_PLAYBACK);
     pcm_apply_settings();
 
+    if (pcmrec_handle > 0)
+        pcmrec_handle = core_free(pcmrec_handle);
+    talk_buffer_set_policy(TALK_BUFFER_DEFAULT);
+
     send_event(RECORDING_EVENT_STOP, NULL);
 }
 
diff --git a/apps/recorder/recording.c b/apps/recorder/recording.c
index 1c3460fbd0..4a7399b01e 100644
--- a/apps/recorder/recording.c
+++ b/apps/recorder/recording.c
@@ -691,15 +691,8 @@ void rec_set_source(int source, unsigned flags)
 
 void rec_set_recording_options(struct audio_recording_options *options)
 {
-#if CONFIG_CODEC != SWCODEC
-    if (global_settings.rec_prerecord_time)
-    {
-        talk_buffer_steal(); /* will use the mp3 buffer */
-    }
-#else /* == SWCODEC */
     rec_set_source(options->rec_source,
                    options->rec_source_flags | SRCF_RECORDING);
-#endif /* CONFIG_CODEC != SWCODEC */
 
     audio_set_recording_options(options);
 }
@@ -724,9 +717,6 @@ void rec_command(enum recording_command cmd)
             /* steal mp3 buffer, create unique filename and start recording */
             pm_reset_clipcount();
             pm_activate_clipcount(true);
-#if CONFIG_CODEC != SWCODEC
-            talk_buffer_steal(); /* we use the mp3 buffer */
-#endif
             audio_record(rec_create_filename(path_buffer));
             break;
         case RECORDING_CMD_START_NEWFILE: