Pjsua crash after wav player destroyed inside the eof callback (thanks Tanguy Floc'h)

[nanang]

​http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/2008-April/002513.html
after destroyed, wav player port get_frame() returns PJ_SUCCESS to conference, so the conference continue accessing the wav player port.

[nanang]

In ticket526.patch contains major changes on wav player:

• On EOF, fill_buffer() NO_LOOP will pad the buffer with zero, for LOOP mode it will rewind the file and fill the end of buffer with the the beginning of file (smooth rewinding).
• Added new field eofpos to mark the end of file position in the buffer, this field only set when eof is set, otherwise it must be NULL.
• EOF callback is not called before/at the EOF frame anymore, it is called in the first next get_frame() after the EOF frame returned.

[bennylp]

Committed ticket526.patch in r1927

[nanang]

Fixed buggy patch 'ticket526.patch': posibility of accessing port after wav player port destroyed

[bennylp]

Committed ticket526.2.patch in r1934