Update documentation

* JUnit Support -> JUnit XML Support
* Combine two sentences in check.texi
* xml->XML
* Add a line in the environment appendix
* Update the xml_format source code header comment
* Add a comment to xml_format

Author: Trever Shick

doc/check.texi

@@ -2052,12 +2052,11 @@ If both plain text and XML log files are specified, by any of above methods,
 then check will log to both files. In other words logging in plain text and XML
 format simultaneously is supported.
 
-JUnit Support is also available.  It is enabled  by a call to 
-@code{srunner_set_xml_format(CK_XML_FORMAT_JUNIT)} before the tests are run. 
-It can also be enabled by environment variable as well.  It is enabled by setting the
-@code{CK_XML_FORMAT_NAME} environment variable to @code{junit}.
+JUnit XML Support is also available.  It is enabled  by a call to
+@code{srunner_set_xml_format(CK_XML_FORMAT_JUNIT)} before the tests are run.
+It can also be enabled by setting the environment variable @code{CK_XML_FORMAT_NAME} to @code{junit}.
 
-Here is an example of the JUnit xml format:
+Here is an example of the JUnit XML format:
 @example
 @verbatim
 <?xml version="1.0" encoding="UTF-8"?>
@@ -2364,6 +2363,8 @@ CK_LOG_FILE_NAME: Filename to write logs to.  See section @ref{Test Logging}.
 
 CK_XML_LOG_FILE_NAME: Filename to write XML log to. See section @ref{XML Logging}.
 
+CK_XML_FORMAT_NAME: Name of the XML format to use. ``junit'' will output in JUnit XML format, all other values will yield the default XML format. @ref{XML Logging}.
+
 CK_TAP_LOG_FILE_NAME: Filename to write TAP (Test Anything Protocol) output to.  See section @ref{TAP Logging}.
 
 CK_MAX_MSG_SIZE: Maximal assertion message size.

src/check.h.in

@@ -2285,11 +2285,15 @@ enum xml_format {
  * Returns the XML format used if XML is to be logged.
  *
  * This value can be explicitly set via `srunner_set_xml_format` or can
- * be set via the CK_XML_FORMAT_NAME environment variable.  
+ * be set via the CK_XML_FORMAT_NAME environment variable.
  *
+ * This setting does not conflict with the other log output types;
+ * all logging types can occur concurrently if configured.
  * @return CK_XML_FORMAT_DEFAULT unless the format is explicitly set via
  *         `srunner_set_xml_format(sr, CK_XML_FORMAT_JUNIT)` or
- *         `getenv("CK_XML_FORMAT_NAME")` returns "unit"
+ *         `getenv("CK_XML_FORMAT_NAME")` is set to a known value.
+ *         Any value set explicitly via `srunner_set_xml_format` will take
+ *         precedence over the environment variable.
  *
  * @param sr suite runner to check
  *

src/check_impl.h

@@ -122,7 +122,7 @@ struct SRunner
     List *resultlst;            /* List of unit test results */
     const char *log_fname;      /* name of log file */
     const char *xml_fname;      /* name of xml output file */
-    enum xml_format xml_format;
+    enum xml_format xml_format; /* the xml format to use */
     const char *tap_fname;      /* name of tap output file */
     List *loglst;               /* list of Log objects */
     enum fork_status fstat;     /* controls if suites are forked or not