Implement time-based resume and playback start.

This complements offset-based resume and playback start funcionality.
The implementation is global on both HWCODEC and SWCODEC.

Basically, if either the specified elapsed or offset are non-zero,
it indicates a mid-track resume.

To resume by time only, set elapsed to nonzero and offset to zero.
To resume by offset only, set offset to nonzero and elapsed to zero.

Which one the codec uses and which has priority is up to the codec;
however, using an elapsed time covers more cases:

* Codecs not able to use an offset such as VGM or other atomic
formats

* Starting playback at a nonzero elapsed time from a source that
contains no offset, such as a cuesheet

The change re-versions pretty much everything from tagcache to nvram.

Change-Id: Ic7aebb24e99a03ae99585c5e236eba960d163f38
Reviewed-on: http://gerrit.rockbox.org/516
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested: Michael Sevakis <jethead71@rockbox.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/apps/settings.h b/apps/settings.h
index 5b876d3e67..60658f6857 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -266,6 +266,7 @@ struct system_status
 {
     int resume_index;  /* index in playlist (-1 for no active resume) */
     uint32_t resume_crc32; /* crc32 of the name of the file */
+    uint32_t resume_elapsed; /* elapsed time in last file */
     uint32_t resume_offset; /* byte offset in mp3 file */
     int runtime;       /* current runtime since last charge */
     int topruntime;    /* top known runtime */
@@ -282,6 +283,7 @@ struct system_status
 #ifdef HAVE_LCD_BITMAP
     int font_id[NB_SCREENS]; /* font id of the settings font for each screen */
 #endif
+
 };
 
 struct user_settings