Resolve an overlap in the ast_audiohook_flags values.

AST_AUDIOHOOK_TRIGGER_WRITE and AST_AUDIOHOOK_WANTS_DTMF were overlapping which
may have caused unintended side effects.  This patch moves
AST_AUDIOHOOK_TRIGGER_WRITE, and updates AST_AUDIOHOOK_TRIGGER_MODE to reflect
the original intention.

This will affect existing modules that use these flags, so be sure to recompile
as necessary.

(closes issue ASTERISK-19246)
Reported by: feyfre
........

Merged revisions 353598 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@353599 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/audiohook.h

@@ -51,10 +51,15 @@ enum ast_audiohook_direction {
 	AST_AUDIOHOOK_DIRECTION_BOTH,     /*!< Both reading audio in and writing audio out */
 };
 
+/*
+ * The flags here have been shifted around due to an unintended overlap between
+ * AST_AUDIOHOOK_TRIGGER_WRITE and AST_AUDIOHOOK_WANTS_DTMF.  In future Asterisk
+ * releases (Asterisk 11+), these have been reorganized to make more sense.
+ */
 enum ast_audiohook_flags {
-	AST_AUDIOHOOK_TRIGGER_MODE = (3 << 0),  /*!< When audiohook should be triggered to do something */
+	AST_AUDIOHOOK_TRIGGER_MODE = ((1 << 6) | (1 << 0)),  /*!< When audiohook should be triggered to do something */
 	AST_AUDIOHOOK_TRIGGER_READ = (1 << 0),  /*!< Audiohook wants to be triggered when reading audio in */
-	AST_AUDIOHOOK_TRIGGER_WRITE = (2 << 0), /*!< Audiohook wants to be triggered when writing audio out */
+	AST_AUDIOHOOK_TRIGGER_WRITE = (1 << 6), /*!< Audiohook wants to be triggered when writing audio out */
 	AST_AUDIOHOOK_WANTS_DTMF = (1 << 1),    /*!< Audiohook also wants to receive DTMF frames */
 	AST_AUDIOHOOK_TRIGGER_SYNC = (1 << 2),  /*!< Audiohook wants to be triggered when both sides have combined audio available */
 	/*! Audiohooks with this flag set will not allow for a large amount of samples to build up on its
@@ -63,6 +68,8 @@ enum ast_audiohook_flags {
 	AST_AUDIOHOOK_SMALL_QUEUE = (1 << 3),
 	AST_AUDIOHOOK_MUTE_READ = (1 << 4),     /*!< audiohook should be mute frames read */
 	AST_AUDIOHOOK_MUTE_WRITE = (1 << 5),    /*!< audiohook should be mute frames written */
+
+	/* IMPORTANT: When adding new flags, start with (1 << 7) */
 };
 
 enum ast_audiohook_init_flags {