Suggested feature: enable GnuTLS debugging output

["Tor Lillqvist" <tml iki fi>]

It would be nice to be able to turn on GnuTLS's debugging features
through libsoup. Trivial patch below, probably should use libsoup's
existing logging facilities instead in some appropriate way.

--tml

Index: libsoup/soup-gnutls.c
===================================================================
--- libsoup/soup-gnutls.c	(revision 1141)
+++ libsoup/soup-gnutls.c	(working copy)
@@ -29,6 +29,8 @@
 #include "soup-ssl.h"
 #include "soup-misc.h"

+#include <stdio.h>
+
 /**
  * soup_ssl_supported:
  *
@@ -449,6 +459,12 @@
 #endif

 static void
+mylog (int level, const char *str)
+{
+  fputs (str, stdout);
+}
+
+static void
 soup_gnutls_init (void)
 {
 	static volatile gsize inited_gnutls = 0;
@@ -458,6 +474,10 @@
 		gcry_control (GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
 #endif
 		gnutls_global_init ();
+		if (getenv ("LIBSOUP_GNUTLS_DEBUG")) {
+			gnutls_global_set_log_level (atoi (getenv ("LIBSOUP_GNUTLS_DEBUG")));
+			gnutls_global_set_log_function (mylog);
+		}
 		g_once_init_leave (&inited_gnutls, TRUE);
 	}
 }