plugin api: Add audio_pre_ff_rewind to plugin's API

According to wps code audio_pre_ff_rewind function should be called
before any rewinding. It stops playback and automatically resumes it
after audio_ff_rewind call

So, let's add audio_pre_ff_rewind to plugin's API

Lua scipts were tested:
```lua
-- has issue with rewinding
rb.audio("ff_rewind", 0)
```

```lua
-- no issue with rewinding
rb.audio("pre_ff_rewind")
rb.audio("ff_rewind", 0)
```

Change-Id: I2ad6b9c396760b2086bc0a28633a1c80c3512739

apps/plugin.c

@@ -356,6 +356,8 @@ static const struct plugin_api rockbox_api = {
     simplelist_info_init,
     simplelist_show_list,
     yesno_pop,
+    yesno_pop_confirm,
+    sb_set_title_text,
 
     /* action handling */
     get_custom_action,
@@ -363,6 +365,18 @@ static const struct plugin_api rockbox_api = {
 #ifdef HAVE_TOUCHSCREEN
     action_get_touchscreen_press,
     action_get_touchscreen_press_in_vp,
+    action_get_touch_event,
+    action_gesture_reset,
+    action_gesture_get_event_in_vp,
+    action_gesture_get_event,
+    action_gesture_is_valid,
+    action_gesture_is_pressed,
+    gesture_reset,
+    gesture_process,
+    gesture_get_event_in_vp,
+    gesture_vel_reset,
+    gesture_vel_process,
+    gesture_vel_get,
 #endif
     action_userabort,
     core_set_keyremap,
@@ -428,6 +442,9 @@ static const struct plugin_api rockbox_api = {
     crc_32r,
     filetype_get_attr,
     filetype_get_plugin,
+#ifdef HAVE_DIRCACHE
+    dircache_wait,
+#endif
 
     /* dir */
     FS_PREFIX(opendir),
@@ -565,6 +582,7 @@ static const struct plugin_api rockbox_api = {
     strncmp,
     strcasecmp,
     strncasecmp,
+    strstr,
     memset,
     memcpy,
     memmove,
@@ -729,6 +747,7 @@ static const struct plugin_api rockbox_api = {
     audio_resume,
     audio_next,
     audio_prev,
+    audio_pre_ff_rewind,
     audio_ff_rewind,
     audio_next_track,
     audio_status,
@@ -738,6 +757,7 @@ static const struct plugin_api rockbox_api = {
 #ifdef PLUGIN_USE_IRAM
     audio_hard_stop,
 #endif
+    add_playbacklog,
 
     /* menu */
     root_menu_get_options,
@@ -761,6 +781,7 @@ static const struct plugin_api rockbox_api = {
 #endif
 
     /* power */
+    &device_battery_tables,
     battery_level,
     battery_level_safe,
     battery_time,
@@ -772,12 +793,17 @@ static const struct plugin_api rockbox_api = {
     charging_state,
 # endif
 #endif
+
     /* usb */
     usb_inserted,
     usb_acknowledge,
 #ifdef USB_ENABLE_HID
     usb_hid_send,
 #endif
+#ifdef USB_ENABLE_AUDIO
+    usb_audio_get_playing,
+#endif
+
     /* misc */
 #if (CONFIG_PLATFORM & PLATFORM_NATIVE)
     __errno,
@@ -849,31 +875,6 @@ static const struct plugin_api rockbox_api = {
 
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
-    add_playbacklog,
-    &device_battery_tables,
-    yesno_pop_confirm,
-#ifdef USB_ENABLE_AUDIO
-    usb_audio_get_playing,
-#endif
-#ifdef HAVE_TOUCHSCREEN
-    action_get_touch_event,
-    action_gesture_reset,
-    action_gesture_get_event_in_vp,
-    action_gesture_get_event,
-    action_gesture_is_valid,
-    action_gesture_is_pressed,
-    gesture_reset,
-    gesture_process,
-    gesture_get_event_in_vp,
-    gesture_vel_reset,
-    gesture_vel_process,
-    gesture_vel_get,
-#endif
-    strstr,
-    sb_set_title_text,
-#ifdef HAVE_DIRCACHE
-    dircache_wait,
-#endif
 };
 
 static int plugin_buffer_handle;

apps/plugin.h

@@ -178,7 +178,7 @@ int plugin_open(const char *plugin, const char *parameter);
  * when this happens please take the opportunity to sort in
  * any new functions "waiting" at the end of the list.
  */
-#define PLUGIN_API_VERSION 274
+#define PLUGIN_API_VERSION 275
 
 /* 239 Marks the removal of ARCHOS HWCODEC and CHARCELL */
 
@@ -418,6 +418,8 @@ struct plugin_api {
                                  int count, void* data);
     bool (*simplelist_show_list)(struct simplelist_info *info);
     bool (*yesno_pop)(const char* text);
+    bool (*yesno_pop_confirm)(const char* text);
+    bool (*sb_set_title_text)(const char* title, enum themable_icons icon, enum screen_type screen);
 
     /* action handling */
     int (*get_custom_action)(int context,int timeout,
@@ -426,6 +428,22 @@ struct plugin_api {
 #ifdef HAVE_TOUCHSCREEN
     int (*action_get_touchscreen_press)(short *x, short *y);
     int (*action_get_touchscreen_press_in_vp)(short *x1, short *y1, struct viewport *vp);
+    int (*action_get_touch_event)(struct touchevent *ev);
+    void (*action_gesture_reset)(void);
+    bool (*action_gesture_get_event_in_vp)(struct gesture_event *gevt,
+                                           const struct viewport *vp);
+    bool (*action_gesture_get_event)(struct gesture_event *gevt);
+    bool (*action_gesture_is_valid)(void);
+    bool (*action_gesture_is_pressed)(void);
+    void (*gesture_reset)(struct gesture *g);
+    void (*gesture_process)(struct gesture *g, const struct touchevent *ev);
+    bool (*gesture_get_event_in_vp)(struct gesture *g,
+                                    struct gesture_event *gevt,
+                                    const struct viewport *vp);
+    void (*gesture_vel_reset)(struct gesture_vel *gv);
+    void (*gesture_vel_process)(struct gesture_vel *gv,
+                                const struct touchevent *ev);
+    bool (*gesture_vel_get)(struct gesture_vel *gv, int *xvel, int *yvel);
 #endif
     bool (*action_userabort)(int timeout);
     int (*core_set_keyremap)(struct button_mapping* core_keymap, int count);
@@ -493,6 +511,9 @@ struct plugin_api {
 
     int (*filetype_get_attr)(const char* file);
     char* (*filetype_get_plugin)(int attr, char *buffer, size_t buffer_len);
+#ifdef HAVE_DIRCACHE
+    void (*dircache_wait)(void);
+#endif
 
     /* dir */
     DIR * (*opendir)(const char *dirname);
@@ -652,6 +673,7 @@ struct plugin_api {
     int (*strncmp)(const char *, const char *, size_t);
     int (*strcasecmp)(const char *, const char *);
     int (*strncasecmp)(const char *s1, const char *s2, size_t n);
+    char* (*strstr)(const char *s1, const char *s2);
     void* (*memset)(void *dst, int c, size_t length);
     void* (*memcpy)(void *out, const void *in, size_t n);
     void* (*memmove)(void *out, const void *in, size_t n);
@@ -853,6 +875,7 @@ struct plugin_api {
     void (*audio_resume)(void);
     void (*audio_next)(void);
     void (*audio_prev)(void);
+    void (*audio_pre_ff_rewind)(void);
     void (*audio_ff_rewind)(long newtime);
     struct mp3entry* (*audio_next_track)(void);
     int (*audio_status)(void);
@@ -862,6 +885,7 @@ struct plugin_api {
 #ifdef PLUGIN_USE_IRAM
     void (*audio_hard_stop)(void);
 #endif
+    void (*add_playbacklog)(struct mp3entry *id3);
 
     /* menu */
     struct menu_table *(*root_menu_get_options)(int *nb_options);
@@ -902,6 +926,7 @@ struct plugin_api {
 #endif
 
     /* power */
+    struct battery_tables_t *device_battery_tables;
     int (*battery_level)(void);
     bool (*battery_level_safe)(void);
     int (*battery_time)(void);
@@ -913,12 +938,17 @@ struct plugin_api {
     bool (*charging_state)(void);
 # endif
 #endif
+
     /* usb */
     bool (*usb_inserted)(void);
     void (*usb_acknowledge)(long id);
 #ifdef USB_ENABLE_HID
     void (*usb_hid_send)(usage_page_t usage_page, int id);
 #endif
+#ifdef USB_ENABLE_AUDIO
+    bool (*usb_audio_get_playing)(void);
+#endif
+
     /* misc */
 #if (CONFIG_PLATFORM & PLATFORM_NATIVE)
     int * (*__errno)(void);
@@ -994,37 +1024,9 @@ struct plugin_api {
 #ifdef HAVE_MULTIVOLUME
     int (*path_strip_volume)(const char *name, const char **nameptr, bool greedy);
 #endif
+
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
-    void (*add_playbacklog)(struct mp3entry *id3);
-    struct battery_tables_t *device_battery_tables;
-    bool (*yesno_pop_confirm)(const char* text);
-#ifdef USB_ENABLE_AUDIO
-    bool (*usb_audio_get_playing)(void);
-#endif
-#ifdef HAVE_TOUCHSCREEN
-    int (*action_get_touch_event)(struct touchevent *ev);
-    void (*action_gesture_reset)(void);
-    bool (*action_gesture_get_event_in_vp)(struct gesture_event *gevt,
-                                           const struct viewport *vp);
-    bool (*action_gesture_get_event)(struct gesture_event *gevt);
-    bool (*action_gesture_is_valid)(void);
-    bool (*action_gesture_is_pressed)(void);
-    void (*gesture_reset)(struct gesture *g);
-    void (*gesture_process)(struct gesture *g, const struct touchevent *ev);
-    bool (*gesture_get_event_in_vp)(struct gesture *g,
-                                    struct gesture_event *gevt,
-                                    const struct viewport *vp);
-    void (*gesture_vel_reset)(struct gesture_vel *gv);
-    void (*gesture_vel_process)(struct gesture_vel *gv,
-                                const struct touchevent *ev);
-    bool (*gesture_vel_get)(struct gesture_vel *gv, int *xvel, int *yvel);
-#endif
-    char* (*strstr)(const char *s1, const char *s2);
-    bool (*sb_set_title_text)(const char* title, enum themable_icons icon, enum screen_type screen);
-#ifdef HAVE_DIRCACHE
-    void (*dircache_wait)(void);
-#endif
 };
 
 /* plugin header */

apps/plugins/lua/include_lua/audio.lua

@@ -31,6 +31,7 @@ rb.audio_pause = function() rb.audio("pause") end
 rb.audio_resume = function() rb.audio("resume") end
 rb.audio_next = function() rb.audio("next") end
 rb.audio_prev = function() rb.audio("prev") end
+rb.audio_pre_ff_rewind = function () rb.audio("pre_ff_rewind") end
 rb.audio_ff_rewind = function (newtime) rb.audio("ff_rewind", newtime) end
 rb.audio_flush_and_reload_tracks = function() rb.audio("flush_and_reload_tracks") end
 rb.audio_get_file_pos = function() return rb.audio("get_file_pos") end

apps/plugins/lua/rocklib.c

@@ -410,12 +410,12 @@ RB_WRAP(playlist)
 RB_WRAP(audio)
 {
     enum e_audio {AUDIO_STATUS = 0, AUDIO_PLAY, AUDIO_STOP, AUDIO_PAUSE,
-                  AUDIO_RESUME, AUDIO_NEXT, AUDIO_PREV, AUDIO_FFREWIND,
-                  AUDIO_FLUSHANDRELOADTRACKS, AUDIO_GETPOS, AUDIO_LENGTH,
-                  AUDIO_ELAPSED, AUDIO_ECOUNT};
+                  AUDIO_RESUME, AUDIO_NEXT, AUDIO_PREV, AUDIO_PREFFREWIND,
+                  AUDIO_FFREWIND, AUDIO_FLUSHANDRELOADTRACKS, AUDIO_GETPOS,
+                  AUDIO_LENGTH, AUDIO_ELAPSED, AUDIO_ECOUNT};
     const char *audio_option[] = {"status", "play", "stop",
                                   "pause", "resume", "next",
-                                  "prev", "ff_rewind",
+                                  "prev", "pre_ff_rewind", "ff_rewind",
                                   "flush_and_reload_tracks",
                                   "get_file_pos", "length",
                                   "elapsed", NULL};
@@ -434,6 +434,7 @@ RB_WRAP(audio)
             if (status == (AUDIO_STATUS_PLAY | AUDIO_STATUS_PAUSE))
             {
                 /* not perfect but provides a decent compromise */
+                rb->audio_pre_ff_rewind();
                 rb->audio_ff_rewind(elapsed + offset);
                 rb->audio_resume();
             }
@@ -456,6 +457,9 @@ RB_WRAP(audio)
         case AUDIO_PREV:
             rb->audio_prev();
             break;
+        case AUDIO_PREFFREWIND:
+            rb->audio_pre_ff_rewind();
+            break;
         case AUDIO_FFREWIND:
             newtime = (long) luaL_checkint(L, 2);
             rb->audio_ff_rewind(newtime);

apps/plugins/lua/rocklib_aux.pl

@@ -97,7 +97,7 @@ my @forbidden_functions = ('^atoi$',
                            '^__.+$',
                            '^.+_(un)?cached$',
                            '^audio_(status|get_file_pos|flush_and_reload_tracks)$',
-                           '^audio_(ff_rewind|next|prev|play|pause|resume|stop)$',
+                           '^audio_(pre_ff_rewind|ff_rewind|next|prev|play|pause|resume|stop)$',
                            '^playlist_(amount|add|create|start|resume|shuffle)$',
                            '^playlist_(sync|resume_track|remove_all_tracks)$',
                            '^playlist_(insert_track|insert_directory)$',

docs/PLUGIN_API

@@ -89,6 +89,10 @@ struct mp3entry* audio_current_track(void)
     \description
     \see [S[firmware/export/id3.h]]
 
+void audio_pre_ff_rewind(void)
+    \group playback control
+    \description prepare playback for rewinding. Playback will be paused
+
 void audio_ff_rewind(long newtime)
     \group playback control
     \param newtime

firmware/export/audio.h

@@ -61,6 +61,7 @@ size_t audio_buffer_size(void);
 /* size of the buffer available for allocating memory from the audio buffer using core_*()
  * returns core_available() if audio buffer is not allocated yet */
 size_t audio_buffer_available(void);
+void audio_pre_ff_rewind(void);
 void audio_ff_rewind(long newpos);
 void audio_flush_and_reload_tracks(void);
 struct mp3entry* audio_current_track(void);