Remove some spammy debug messages; improve clarity of others

Debug messages aren't free. Even when the debug level is sufficiently low such
that the messages are never evaluated, there is a cost to having to parse
Asterisk logs that contain debug messages that (a) fail to convey sufficient
information or (b) occur so frequently as to be next to meaningless. Based on
having to stare at lots of DEBUG messages, this patch makes the following
changes:

* channel.c: When copying variables from a parent channel to a child channel,
  specify the channels involved. Do not log anything for a variable that is not
  inherited; the fact that it doesn't have an _ or __ already signifies that it
  won't be inherited.
* pbx.c: Specify what function evaluation has occurred that created the result.
* translate.c: Bump up the translator path messages to 10. I've never once had
  to use these debug messages, and for each format that is registered (on
  startup) and unregistered (on shutdown) the entire f^2 matrix is logged out.
  For short tests in the Asterisk Test Suite, this should make finding the
  actual test much easier.
* xmldoc.c: The debug message that 'blah' is not found in the tree is expected.
  Often, description elements - which are not required - are not provided.
  This debug message adds no additional value, as it is not indicative of an
  error or helpful in debugging which element did not contain a 'blah' element
  as a child. If an element is supposed to contain a child element, then that
  XML tree should have failed validation in the first place.

Review: https://reviewboard.asterisk.org/r/2966/
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Merged revisions 402150 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 402151 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 402154 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@402155 65c4cc65-6c06-0410-ace0-fbb531ad65f3

4 files changed, 7 insertions, 7 deletions

diff --git a/main/channel.c b/main/channel.c
index a38615415..a44279d22 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -6346,18 +6346,19 @@ void ast_channel_inherit_variables(const struct ast_channel *parent, struct ast_
 			newvar = ast_var_assign(&varname[1], ast_var_value(current));
 			if (newvar) {
 				AST_LIST_INSERT_TAIL(ast_channel_varshead(child), newvar, entries);
-				ast_debug(1, "Copying soft-transferable variable %s.\n", ast_var_name(newvar));
+				ast_debug(1, "Inheriting variable %s from %s to %s.\n",
+					ast_var_name(newvar), ast_channel_name(parent), ast_channel_name(child));
 			}
 			break;
 		case 2:
 			newvar = ast_var_assign(varname, ast_var_value(current));
 			if (newvar) {
 				AST_LIST_INSERT_TAIL(ast_channel_varshead(child), newvar, entries);
-				ast_debug(1, "Copying hard-transferable variable %s.\n", ast_var_name(newvar));
+				ast_debug(1, "Inheriting variable %s from %s to %s.\n",
+					ast_var_name(newvar), ast_channel_name(parent), ast_channel_name(child));
 			}
 			break;
 		default:
-			ast_debug(1, "Not copying variable %s.\n", ast_var_name(current));
 			break;
 		}
 	}
diff --git a/main/pbx.c b/main/pbx.c
index 24c34b49f..5c29a0c42 100644
--- a/main/pbx.c
+++ b/main/pbx.c
@@ -4323,7 +4323,7 @@ void ast_str_substitute_variables_full(struct ast_str **buf, ssize_t maxlen, str
 						ast_log(LOG_ERROR, "Unable to allocate bogus channel for variable substitution.  Function results may be blank.\n");
 					}
 				}
-				ast_debug(2, "Function result is '%s'\n", cp4 ? cp4 : "(null)");
+				ast_debug(2, "Function %s result is '%s'\n", finalvars, cp4 ? cp4 : "(null)");
 			} else {
 				/* Retrieve variable value */
 				ast_str_retrieve_variable(&substr3, 0, c, headp, finalvars);
@@ -4523,7 +4523,7 @@ void pbx_substitute_variables_helper_full(struct ast_channel *c, struct varshead
 						ast_log(LOG_ERROR, "Unable to allocate bogus channel for variable substitution.  Function results may be blank.\n");
 					}
 				}
-				ast_debug(2, "Function result is '%s'\n", cp4 ? cp4 : "(null)");
+				ast_debug(2, "Function %s result is '%s'\n", vars, cp4 ? cp4 : "(null)");
 			} else {
 				/* Retrieve variable value */
 				pbx_retrieve_variable(c, vars, &cp4, workspace, VAR_BUF_SIZE, headp);
diff --git a/main/translate.c b/main/translate.c
index 5037b4283..96019f1c7 100644
--- a/main/translate.c
+++ b/main/translate.c
@@ -771,7 +771,7 @@ static void matrix_rebuild(int samples)
 						matrix_get(x, z)->table_cost = newtablecost;
 						matrix_get(x, z)->multistep = 1;
 						changed++;
-						ast_debug(3, "Discovered %d cost path from %s to %s, via %s\n",
+						ast_debug(10, "Discovered %d cost path from %s to %s, via %s\n",
 							matrix_get(x, z)->table_cost,
 							ast_getformatname(ast_format_set(&tmpx, index2format(x), 0)),
 							ast_getformatname(ast_format_set(&tmpy, index2format(z), 0)),
diff --git a/main/xmldoc.c b/main/xmldoc.c
index 80e7830ae..8a54d6f12 100644
--- a/main/xmldoc.c
+++ b/main/xmldoc.c
@@ -2186,7 +2186,6 @@ static char *_xmldoc_build_field(struct ast_xml_node *node, const char *var, int
 	node = ast_xml_find_element(ast_xml_node_get_children(node), var, NULL, NULL);
 
 	if (!node || !ast_xml_node_get_children(node)) {
-		ast_debug(1, "Cannot find variable '%s' in tree\n", var);
 		return ret;
 	}