Use C99 variadic macros when not on GCC.

1) We already require C99.

2) This allows us to support MSVC again (thanks to Gisle Vanem for
   this part)

3) This change allows us to dump some rotten old compatibility code
   from log.c

1 files changed, 32 insertions, 26 deletions

diff --git a/src/common/torlog.h b/src/common/torlog.h
index 710313a9a6..45b2abfd7e 100644
--- a/src/common/torlog.h
+++ b/src/common/torlog.h
@@ -166,7 +166,6 @@ void tor_log_get_logfile_names(struct smartlist_t *out);
 
 extern int log_global_min_severity_;
 
-#if defined(__GNUC__) || defined(RUNNING_DOXYGEN)
 void log_fn_(int severity, log_domain_mask_t domain,
              const char *funcname, const char *format, ...)
   CHECK_PRINTF(4,5);
@@ -175,6 +174,12 @@ void log_fn_ratelim_(struct ratelim_t *ratelim, int severity,
                      log_domain_mask_t domain, const char *funcname,
                      const char *format, ...)
   CHECK_PRINTF(5,6);
+
+#if defined(__GNUC__)
+
+/* These are the GCC varidaic macros, so that older versions of GCC don't
+ * break. */
+
 /** Log a message at level <b>severity</b>, using a pretty-printed version
  * of the current function name. */
 #define log_fn(severity, domain, args...)               \
@@ -200,31 +205,32 @@ void log_fn_ratelim_(struct ratelim_t *ratelim, int severity,
 
 #else /* ! defined(__GNUC__) */
 
-void log_fn_(int severity, log_domain_mask_t domain, const char *format, ...);
-struct ratelim_t;
-void log_fn_ratelim_(struct ratelim_t *ratelim, int severity,
-             log_domain_mask_t domain, const char *format, ...);
-void log_debug_(log_domain_mask_t domain, const char *format, ...);
-void log_info_(log_domain_mask_t domain, const char *format, ...);
-void log_notice_(log_domain_mask_t domain, const char *format, ...);
-void log_warn_(log_domain_mask_t domain, const char *format, ...);
-void log_err_(log_domain_mask_t domain, const char *format, ...);
-
-/* We don't have GCC's varargs macros, so use a global variable to pass the
- * function name to log_fn */
-extern const char *log_fn_function_name_;
-/* We abuse the comma operator here, since we can't use the standard
- * do {...} while (0) trick to wrap this macro, since the macro can't take
- * arguments. */
-#define log_fn (log_fn_function_name_=__func__),log_fn_
-#define log_fn_ratelim (log_fn_function_name_=__func__),log_fn_ratelim_
-#define log_debug (log_fn_function_name_=__func__),log_debug_
-#define log_info (log_fn_function_name_=__func__),log_info_
-#define log_notice (log_fn_function_name_=__func__),log_notice_
-#define log_warn (log_fn_function_name_=__func__),log_warn_
-#define log_err (log_fn_function_name_=__func__),log_err_
-
-#endif /* !GNUC */
+/* Here are the c99 variadic macros, to work with non-GCC compilers */
+
+#define log_debug(domain, args, ...)                                        \
+  STMT_BEGIN                                                                \
+    if (PREDICT_UNLIKELY(log_global_min_severity_ == LOG_DEBUG))            \
+      log_fn_(LOG_DEBUG, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__); \
+  STMT_END
+#define log_info(domain, args,...)                                      \
+  log_fn_(LOG_INFO, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__)
+#define log_notice(domain, args,...)                                    \
+  log_fn_(LOG_NOTICE, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__)
+#define log_warn(domain, args,...)                                      \
+  log_fn_(LOG_WARN, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__)
+#define log_err(domain, args,...)                                       \
+  log_fn_(LOG_ERR, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__)
+/** Log a message at level <b>severity</b>, using a pretty-printed version
+ * of the current function name. */
+#define log_fn(severity, domain, args,...)                              \
+  log_fn_(severity, domain, __PRETTY_FUNCTION__, args, ##__VA_ARGS__)
+/** As log_fn, but use <b>ratelim</b> (an instance of ratelim_t) to control
+ * the frequency at which messages can appear.
+ */
+#define log_fn_ratelim(ratelim, severity, domain, args,...)      \
+  log_fn_ratelim_(ratelim, severity, domain, __PRETTY_FUNCTION__, \
+                  args, ##__VA_ARGS__)
+#endif
 
 #ifdef LOG_PRIVATE
 MOCK_DECL(STATIC void, logv, (int severity, log_domain_mask_t domain,