[glib-networking] Simplify some code with gnutls_x509_crt_export2

[Michael Catanzaro <mcatanzaro src gnome org>]

commit dd94baa6488983eeea6a51489d43a8e912e3dc04
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sun Jun 24 22:43:01 2018 -0500

    Simplify some code with gnutls_x509_crt_export2
    
    The original gnutls_x509_crt_export is complicated to use, and it's not
    needed here, so avoid it.
    
    It's still needed in the property getters, which would require an extra
    copy if they were switch to use export2.

 tls/gnutls/gtlscertificate-gnutls.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)
---
diff --git a/tls/gnutls/gtlscertificate-gnutls.c b/tls/gnutls/gtlscertificate-gnutls.c
index 024d872..17dfd97 100644
--- a/tls/gnutls/gtlscertificate-gnutls.c
+++ b/tls/gnutls/gtlscertificate-gnutls.c
@@ -378,7 +378,6 @@ g_tls_certificate_gnutls_real_copy (GTlsCertificateGnutls    *gnutls,
 {
   GTlsCertificateGnutls *chain;
   guint num_certs = 0;
-  size_t size = 0;
   int status;
 
   /* We will do this loop twice. It's probably more efficient than
@@ -405,17 +404,12 @@ g_tls_certificate_gnutls_real_copy (GTlsCertificateGnutls    *gnutls,
       gnutls_x509_crt_t cert;
       gnutls_datum_t data;
 
-      gnutls_x509_crt_export (priv->cert, GNUTLS_X509_FMT_DER,
-                              NULL, &size);
-      data.data = g_malloc (size);
-      data.size = size;
-      gnutls_x509_crt_export (priv->cert, GNUTLS_X509_FMT_DER,
-                              data.data, &size);
+      gnutls_x509_crt_export2 (priv->cert, GNUTLS_X509_FMT_DER, &data);
 
       gnutls_x509_crt_init (&cert);
       status = gnutls_x509_crt_import (cert, &data, GNUTLS_X509_FMT_DER);
       g_warn_if_fail (status == 0);
-      g_free (data.data);
+      gnutls_free (data.data);
 
       gnutls_pcert_import_x509 (*pcert + *pcert_length, cert, 0);
       gnutls_x509_crt_deinit (cert);