commit 2c2e19d96069f2d94d6c68f50e3ef2175a412cfb
Author: Olav Morken <olav.morken@uninett.no>
Date:   Tue Aug 8 14:34:24 2017 +0200

    Fix incorrect error check for many `lasso_*`-functions.
    
    Several places in the code we assumed that Lasso error codes were
    negative, however some of them are positive integers. This patch
    ensures that we do direct check for a zero return code in all cases.
    
    Fixes issue #128.

diff --git a/auth_mellon_handler.c b/auth_mellon_handler.c
index 70462a7..5661083 100644
--- a/auth_mellon_handler.c
+++ b/auth_mellon_handler.c
@@ -640,7 +640,7 @@ static void am_restore_lasso_profile_state(request_rec *r,
     identity_dump = am_cache_get_lasso_identity(am_session);
     if(identity_dump != NULL) {
         rc = lasso_profile_set_identity_from_dump(profile, identity_dump);
-        if(rc < 0) {
+        if(rc != 0) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                           "Could not restore identity from dump."
                           " Lasso error: [%i] %s", rc, lasso_strerror(rc));
@@ -651,7 +651,7 @@ static void am_restore_lasso_profile_state(request_rec *r,
     session_dump = am_cache_get_lasso_session(am_session);
     if(session_dump != NULL) {
         rc = lasso_profile_set_session_from_dump(profile, session_dump);
-        if(rc < 0) {
+        if(rc != 0) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                           "Could not restore session from dump."
                           " Lasso error: [%i] %s", rc, lasso_strerror(rc));
@@ -1842,7 +1842,7 @@ static int am_handle_reply_common(request_rec *r, LassoLogin *login,
     }
 
     rc = lasso_login_accept_sso(login);
-    if(rc < 0) {
+    if(rc != 0) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                       "Unable to accept SSO message."
                       " Lasso error: [%i] %s", rc, lasso_strerror(rc));
@@ -2157,7 +2157,7 @@ static int am_handle_artifact_reply(request_rec *r)
         rc = lasso_login_init_request(login, r->args,
                                   LASSO_HTTP_METHOD_ARTIFACT_GET);
 
-        if(rc < 0) {
+        if(rc != 0) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                           "Failed to handle login response."
                           " Lasso error: [%i] %s", rc, lasso_strerror(rc));
@@ -2181,7 +2181,7 @@ static int am_handle_artifact_reply(request_rec *r)
         ap_unescape_url(saml_art);
 
         rc = lasso_login_init_request(login, saml_art, LASSO_HTTP_METHOD_ARTIFACT_POST);
-        if(rc < 0) {
+        if(rc != 0) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                           "Failed to handle login response."
                           " Lasso error: [%i] %s", rc, lasso_strerror(rc));
@@ -2192,7 +2192,7 @@ static int am_handle_artifact_reply(request_rec *r)
 
     /* Prepare SOAP request. */
     rc = lasso_login_build_request_msg(login);
-    if(rc < 0) {
+    if(rc != 0) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                       "Failed to prepare SOAP message for HTTP-Artifact"
                       " resolution."