[evolution] EMailParserMultipartSigned: Rework obtaining the signature protocol.

[Matthew Barnes <mbarnes src gnome org>]

commit e16d918af5c66484bba36fbc140d1eb60aece03d
Author: Matthew Barnes <mbarnes redhat com>
Date:   Wed Oct 2 15:16:46 2013 -0400

    EMailParserMultipartSigned: Rework obtaining the signature protocol.
    
    CamelMultipartSigned no longer has a public 'protocol' member.  Obtain
    it instead by checking the CamelContentType for a 'protocol' parameter.

 em-format/e-mail-parser-multipart-signed.c |   40 ++++++++++++++++-----------
 1 files changed, 24 insertions(+), 16 deletions(-)
---
diff --git a/em-format/e-mail-parser-multipart-signed.c b/em-format/e-mail-parser-multipart-signed.c
index 440d791..1b5c6c6 100644
--- a/em-format/e-mail-parser-multipart-signed.c
+++ b/em-format/e-mail-parser-multipart-signed.c
@@ -51,31 +51,34 @@ empe_mp_signed_parse (EMailParserExtension *extension,
                       GCancellable *cancellable,
                       GQueue *out_mail_parts)
 {
-       CamelMimePart *cpart;
-       CamelMultipartSigned *mps;
+       CamelMimePart *cpart = NULL;
+       CamelMultipart *multipart;
        CamelCipherContext *cipher = NULL;
+       CamelContentType *content_type;
        CamelSession *session;
        guint32 validity_type;
        CamelCipherValidity *valid;
+       const gchar *protocol = NULL;
        GError *local_error = NULL;
        gint i, nparts, len;
        gboolean secured;
 
        /* If the part is application/pgp-signature sub-part then skip it. */
        if (!CAMEL_IS_MULTIPART (part)) {
-               CamelContentType *ct;
-               ct = camel_mime_part_get_content_type (CAMEL_MIME_PART (part));
-               if (camel_content_type_is (ct, "application", "pgp-signature")) {
+               content_type = camel_mime_part_get_content_type (part);
+               if (camel_content_type_is (
+                       content_type, "application", "pgp-signature")) {
                        return TRUE;
                }
        }
 
-       mps = (CamelMultipartSigned *) camel_medium_get_content ((CamelMedium *) part);
-       if (!CAMEL_IS_MULTIPART_SIGNED (mps)
-               || (
+       multipart = (CamelMultipart *) camel_medium_get_content ((CamelMedium *) part);
+       if (CAMEL_IS_MULTIPART_SIGNED (multipart)) {
                cpart = camel_multipart_get_part (
-                       (CamelMultipart *) mps,
-               CAMEL_MULTIPART_SIGNED_CONTENT)) == NULL) {
+                       multipart, CAMEL_MULTIPART_SIGNED_CONTENT);
+       }
+
+       if (cpart == NULL) {
                e_mail_parser_error (
                        parser, out_mail_parts,
                        _("Could not parse MIME message. "
@@ -88,18 +91,23 @@ empe_mp_signed_parse (EMailParserExtension *extension,
                return TRUE;
        }
 
+       content_type = camel_data_wrapper_get_mime_type_field (
+               CAMEL_DATA_WRAPPER (multipart));
+       if (content_type != NULL)
+               protocol = camel_content_type_param (content_type, "protocol");
+
        session = e_mail_parser_get_session (parser);
        /* FIXME: Should be done via a plugin interface */
        /* FIXME: duplicated in em-format-html-display.c */
-       if (mps->protocol) {
+       if (protocol != NULL) {
 #ifdef ENABLE_SMIME
-               if (g_ascii_strcasecmp ("application/x-pkcs7-signature", mps->protocol) == 0
-                   || g_ascii_strcasecmp ("application/pkcs7-signature", mps->protocol) == 0) {
+               if (g_ascii_strcasecmp ("application/x-pkcs7-signature", protocol) == 0
+                   || g_ascii_strcasecmp ("application/pkcs7-signature", protocol) == 0) {
                        cipher = camel_smime_context_new (session);
                        validity_type = E_MAIL_PART_VALIDITY_SMIME;
                } else {
 #endif
-                       if (g_ascii_strcasecmp ("application/pgp-signature", mps->protocol) == 0) {
+                       if (g_ascii_strcasecmp ("application/pgp-signature", protocol) == 0) {
                                cipher = camel_gpg_context_new (session);
                                validity_type = E_MAIL_PART_VALIDITY_PGP;
                        }
@@ -137,7 +145,7 @@ empe_mp_signed_parse (EMailParserExtension *extension,
                return TRUE;
        }
 
-       nparts = camel_multipart_get_number (CAMEL_MULTIPART (mps));
+       nparts = camel_multipart_get_number (multipart);
        secured = FALSE;
        len = part_id->len;
        for (i = 0; i < nparts; i++) {
@@ -145,7 +153,7 @@ empe_mp_signed_parse (EMailParserExtension *extension,
                GList *head, *link;
                CamelMimePart *subpart;
 
-               subpart = camel_multipart_get_part (CAMEL_MULTIPART (mps), i);
+               subpart = camel_multipart_get_part (multipart, i);
 
                g_string_append_printf (part_id, ".signed.%d", i);