If someone were to delete the files used by an existing MOH class, and then

issue a reload, further use of that class could result in a crash due to
dividing by zero.  This set of changes fixes up some places to prevent this
from happening.

(closes issue #10948)
Reported by: jcomellas
Patches:
      res_musiconhold_division_by_zero.patch uploaded by jcomellas (license 282)
	  Additional changes added by me.

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@89037 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/res/res_musiconhold.c b/res/res_musiconhold.c
index bc6273f30d4f68e74a8eefbb35b04dc13e56158c..1680cffea5f41d889d445e740ec84e78464c64e7 100644 (file)
--- a/res/res_musiconhold.c
+++ b/res/res_musiconhold.c
@@ -231,6 +231,11 @@ static int ast_moh_files_next(struct ast_channel *chan)
                chan->stream = NULL;
        }
 
+       if (!state->class->total_files) {
+               ast_log(LOG_WARNING, "No files available for class '%s'\n", state->class->name);
+               return -1;
+       }
+
        /* If a specific file has been saved, use it */
        if (state->save_pos >= 0) {
                state->pos = state->save_pos;
@@ -321,7 +326,7 @@ static void *moh_files_alloc(struct ast_channel *chan, void *params)
                        /* initialize */
                        memset(state, 0, sizeof(*state));
                        state->class = class;
-                       if (ast_test_flag(state->class, MOH_RANDOMIZE))
+                       if (ast_test_flag(state->class, MOH_RANDOMIZE) && class->total_files)
                                state->pos = ast_random() % class->total_files;
                }
 
@@ -1259,8 +1264,15 @@ static int init_classes(int reload)
                        AST_LIST_REMOVE_CURRENT(&mohclasses, list);
                        if (!moh->inuse)
                                ast_moh_destroy_one(moh);
-               } else if (moh->total_files)
-                       moh_scan_files(moh);
+               } else if (moh->total_files) {
+                       if (moh_scan_files(moh)) {
+                               ast_log(LOG_WARNING, "No files found for class '%s'\n", moh->name);
+                               moh->delete = 1;
+                               AST_LIST_REMOVE_CURRENT(&mohclasses, list);
+                               if (!moh->inuse)
+                                       ast_moh_destroy_one(moh);
+                       }
+               }
        }
        AST_LIST_TRAVERSE_SAFE_END
        AST_LIST_UNLOCK(&mohclasses);