Synchronize mailimap deletion against async operations

[claws.git] / src / etpan / imap-thread.c

diff --git a/src/etpan/imap-thread.c b/src/etpan/imap-thread.c
index 229f29e4167150ffd9648acae786fcfe0e1d200b..4998e33af9617fccf881f16fc605738bd54fdae7 100644 (file)
--- a/src/etpan/imap-thread.c
+++ b/src/etpan/imap-thread.c
@@ -59,26 +59,6 @@ static chash * session_hash = NULL;
 static guint thread_manager_signal = 0;
 static GIOChannel * io_channel = NULL;
 
-static void delete_imap(Folder *folder, mailimap *imap)
-{
-       chashdatum key;
-
-       key.data = &folder;
-       key.len = sizeof(folder);
-       chash_delete(session_hash, &key, NULL);
-       
-       key.data = &imap;
-       key.len = sizeof(imap);
-       chash_delete(courier_workaround_hash, &key, NULL);
-       if (imap && imap->imap_stream) {
-               /* we don't want libetpan to logout */
-               mailstream_close(imap->imap_stream);
-               imap->imap_stream = NULL;
-       }
-       debug_print("removing mailimap %p\n", imap);
-       mailimap_free(imap);    
-}
-
 static gboolean thread_manager_event(GIOChannel * source,
     GIOCondition condition,
     gpointer data)
@@ -416,17 +396,23 @@ static void generic_cb(int cancelled, void * result, void * callback_data)
        op->finished = 1;
 }
 
-static void threaded_run(Folder * folder, void * param, void * result,
-                        void (* func)(struct etpan_thread_op * ))
+/* Please do *not* blindly use imap pointers after this function returns,
+ * someone may have deleted it while this function was waiting for completion.
+ * Check return value to see if imap is still valid.
+ * Run get_imap(folder) again to get a fresh and valid pointer.
+ */
+static int threaded_run(Folder * folder, void * param, void * result,
+                       void (* func)(struct etpan_thread_op * ))
 {
        struct etpan_thread_op * op;
        struct etpan_thread * thread;
+       struct mailimap * imap = get_imap(folder);
        
        imap_folder_ref(folder);
 
        op = etpan_thread_op_new();
        
-       op->imap = get_imap(folder);
+       op->imap = imap;
        op->param = param;
        op->result = result;
        
@@ -444,10 +430,17 @@ static void threaded_run(Folder * folder, void * param, void * result,
        while (!op->finished) {
                gtk_main_iteration();
        }
-       
+
        etpan_thread_op_free(op);
 
        imap_folder_unref(folder);
+
+       if (imap != get_imap(folder)) {
+               g_warning("returning from operation on a stale imap %p", imap);
+               return 1;
+       }
+
+       return 0;
 }
 
 
@@ -471,6 +464,55 @@ struct connect_result {
        }                                                       \
 }
 
+
+static void delete_imap_run(struct etpan_thread_op * op)
+{
+       mailimap * imap = op->imap;
+
+       /* we don't want libetpan to logout */
+       if (imap->imap_stream) {
+               mailstream_close(imap->imap_stream);
+               imap->imap_stream = NULL;
+       }
+
+       mailimap_free(imap);
+}
+
+static void threaded_delete_imap(Folder *folder, mailimap *imap)
+{
+       struct etpan_thread_op * op;
+
+       /* No need to wait for completion, threaded_run() won't work here. */
+       op = etpan_thread_op_new();
+       op->imap = imap;
+       op->run = delete_imap_run;
+       op->cleanup = etpan_thread_op_free;
+
+       etpan_thread_op_schedule(get_thread(folder), op);
+
+       debug_print("threaded delete imap posted\n");
+}
+
+static void delete_imap(Folder *folder, mailimap *imap)
+{
+       chashdatum key;
+
+       key.data = &folder;
+       key.len = sizeof(folder);
+       chash_delete(session_hash, &key, NULL);
+
+       if (!imap)
+               return;
+       key.data = &imap;
+       key.len = sizeof(imap);
+       chash_delete(courier_workaround_hash, &key, NULL);
+       /* We can't just free imap here as there may be ops on it pending
+        * in the thread. Posting freeing as an op will synchronize against
+        * existing jobs and as imap is already removed from session_hash
+        * we are sure no new ops can be posted. */
+       threaded_delete_imap(folder, imap);
+}
+
 static void connect_run(struct etpan_thread_op * op)
 {
        int r;
@@ -574,7 +616,8 @@ int imap_threaded_connect_ssl(Folder * folder, const char * server, int port)
                accept_if_valid = folder->account->ssl_certs_auto_accept;
 
        refresh_resolvers();
-       threaded_run(folder, &param, &result, connect_ssl_run);
+       if (threaded_run(folder, &param, &result, connect_ssl_run))
+               return MAILIMAP_ERROR_INVAL;
 
        if ((result.error == MAILIMAP_NO_ERROR_AUTHENTICATED ||
             result.error == MAILIMAP_NO_ERROR_NON_AUTHENTICATED) && !etpan_skip_ssl_cert_check) {
@@ -615,7 +658,7 @@ static void capability_run(struct etpan_thread_op * op)
 }
 
 
-struct mailimap_capability_data * imap_threaded_capability(Folder *folder, int *ok)
+int imap_threaded_capability(Folder *folder, struct mailimap_capability_data ** caps)
 {
        struct capa_param param;
        struct capa_result result;
@@ -629,10 +672,10 @@ struct mailimap_capability_data * imap_threaded_capability(Folder *folder, int *
        
        debug_print("capa %d\n", result.error);
        
-       if (ok)
-               *ok = result.error;
+       if (result.error == MAILIMAP_NO_ERROR)
+               *caps = result.caps;
 
-       return result.caps;
+       return result.error;
        
 }
        
@@ -674,13 +717,11 @@ void imap_threaded_disconnect(Folder * folder)
        
        param.imap = imap;
        
-       threaded_run(folder, &param, &result, disconnect_run);
-       
-       if (imap == get_imap(folder)) {
+       if (threaded_run(folder, &param, &result, disconnect_run)) {
+               debug_print("imap already deleted %p\n", imap);
+       } else {
                debug_print("deleting old imap %p\n", imap);
                delete_imap(folder, imap);
-       } else {
-               debug_print("imap already deleted %p\n", imap);
        }
        
        debug_print("disconnect ok\n");
@@ -1025,8 +1066,9 @@ int imap_threaded_noop(Folder * folder, unsigned int * p_exists,
        imap = get_imap(folder);
        param.imap = imap;
 
-       threaded_run(folder, &param, &result, noop_run);
-       
+       if (threaded_run(folder, &param, &result, noop_run))
+               return MAILIMAP_ERROR_INVAL;
+
        if (result.error == 0 && imap && imap->imap_selection_info != NULL) {
                * p_exists = imap->imap_selection_info->sel_exists;
                * p_recent = imap->imap_selection_info->sel_recent;
@@ -1115,7 +1157,8 @@ int imap_threaded_starttls(Folder * folder, const gchar *host, int port)
        if (folder->account)
                accept_if_valid = folder->account->ssl_certs_auto_accept;
 
-       threaded_run(folder, &param, &result, starttls_run);
+       if (threaded_run(folder, &param, &result, starttls_run))
+               return MAILIMAP_ERROR_INVAL;
 
        debug_print("imap starttls - end\n");
 
@@ -1309,8 +1352,9 @@ int imap_threaded_select(Folder * folder, const char * mb,
        param.imap = imap;
        param.mb = mb;
        
-       threaded_run(folder, &param, &result, select_run);
-       
+       if (threaded_run(folder, &param, &result, select_run))
+               return MAILIMAP_ERROR_INVAL;
+
        if (result.error != MAILIMAP_NO_ERROR)
                return result.error;
        
@@ -1460,8 +1504,9 @@ int imap_threaded_examine(Folder * folder, const char * mb,
        param.imap = imap;
        param.mb = mb;
        
-       threaded_run(folder, &param, &result, examine_run);
-       
+       if (threaded_run(folder, &param, &result, examine_run))
+               return MAILIMAP_ERROR_INVAL;
+
        if (result.error != MAILIMAP_NO_ERROR)
                return result.error;
        
@@ -2903,8 +2948,9 @@ int imap_threaded_fetch_env(Folder * folder, struct mailimap_set * set,
        param.imap = imap;
        param.set = set;
        
-       threaded_run(folder, &param, &result, fetch_env_run);
-       
+       if (threaded_run(folder, &param, &result, fetch_env_run))
+               return MAILIMAP_ERROR_INVAL;
+
        if (result.error != MAILIMAP_NO_ERROR) {
                chashdatum key;
                chashdatum value;