udscs: Let the read call back take owner ship of the data

This avoids the need to do a memcpy if the read callback wants to keep
the data around. This makes the read callback responsible for freeing the
buffer.

6 files changed, 16 insertions, 6 deletions

diff --git a/udscs.c b/udscs.c
index 2ebbadf..fc5e333 100644
--- a/udscs.c
+++ b/udscs.c
@@ -466,7 +466,6 @@ static void udscs_read_complete(struct udscs_connection **connp)
             return;
     }
 
-    free(conn->data.buf);
     conn->header_read = 0;
     memset(&conn->data, 0, sizeof(conn->data));
 }
diff --git a/udscs.h b/udscs.h
index 2bb9bba..72e58ed 100644
--- a/udscs.h
+++ b/udscs.h
@@ -42,7 +42,7 @@ typedef void (*udscs_connect_callback)(struct udscs_connection *conn);
    received. The callback may call udscs_destroy_connection, in which case
    *connp must be made NULL (which udscs_destroy_connection takes care of) */
 typedef void (*udscs_read_callback)(struct udscs_connection **connp,
-    struct udscs_message_header *header, const uint8_t *data);
+    struct udscs_message_header *header, uint8_t *data);
 /* Callback type for udscs_server_for_all_clients. Clients can be disconnected
    from this callback just like with a read callback. */
 typedef int (*udscs_for_all_clients_callback)(struct udscs_connection **connp,
diff --git a/vdagent-x11.c b/vdagent-x11.c
index 5febe71..fd4d1ec 100644
--- a/vdagent-x11.c
+++ b/vdagent-x11.c
@@ -905,7 +905,7 @@ void vdagent_x11_clipboard_grab(struct vdagent_x11 *x11, uint32_t *types,
 }
 
 void vdagent_x11_clipboard_data(struct vdagent_x11 *x11, uint32_t type,
-    const uint8_t *data, uint32_t size)
+    uint8_t *data, uint32_t size)
 {
     Atom prop;
     XEvent *event;
@@ -914,6 +914,7 @@ void vdagent_x11_clipboard_data(struct vdagent_x11 *x11, uint32_t type,
     if (!x11->selection_request) {
         fprintf(x11->errfile, "received clipboard data without an outstanding"
                               "selection request, ignoring\n");
+        free(data);
         return;
     }
 
@@ -924,6 +925,7 @@ void vdagent_x11_clipboard_data(struct vdagent_x11 *x11, uint32_t type,
         fprintf(x11->errfile, "expecting type %u clipboard data got %u\n",
                 type_from_event, type);
         vdagent_x11_send_selection_notify(x11, None, 1);
+        free(data);
         return;
     }
 
@@ -936,6 +938,7 @@ void vdagent_x11_clipboard_data(struct vdagent_x11 *x11, uint32_t type,
                     event->xselectionrequest.target, 8, PropModeReplace,
                     data, size);
     vdagent_x11_send_selection_notify(x11, prop, 1);
+    free(data);
 }
 
 void vdagent_x11_clipboard_release(struct vdagent_x11 *x11)
diff --git a/vdagent-x11.h b/vdagent-x11.h
index 55baf82..10f27ee 100644
--- a/vdagent-x11.h
+++ b/vdagent-x11.h
@@ -41,7 +41,7 @@ void vdagent_x11_clipboard_grab(struct vdagent_x11 *x11, uint32_t *types,
     uint32_t type_count);
 void vdagent_x11_clipboard_request(struct vdagent_x11 *x11, uint32_t type);
 void vdagent_x11_clipboard_data(struct vdagent_x11 *x11, uint32_t type,
-    const uint8_t *data, uint32_t size);
+    uint8_t *data, uint32_t size);
 void vdagent_x11_clipboard_release(struct vdagent_x11 *x11);
 
 #endif
diff --git a/vdagent.c b/vdagent.c
index 233fd2c..7f1bee9 100644
--- a/vdagent.c
+++ b/vdagent.c
@@ -42,29 +42,36 @@ static FILE *logfile = NULL;
 static int quit = 0;
 
 void daemon_read_complete(struct udscs_connection **connp,
-    struct udscs_message_header *header, const uint8_t *data)
+    struct udscs_message_header *header, uint8_t *data)
 {
     switch (header->type) {
     case VDAGENTD_MONITORS_CONFIG:
         vdagent_x11_set_monitor_config(x11, (VDAgentMonitorsConfig *)data);
+        free(data);
         break;
     case VDAGENTD_CLIPBOARD_REQUEST:
         vdagent_x11_clipboard_request(x11, header->opaque);
+        free(data);
         break;
     case VDAGENTD_CLIPBOARD_GRAB:
         vdagent_x11_clipboard_grab(x11, (uint32_t *)data,
                                    header->size / sizeof(uint32_t));
+        free(data);
         break;
     case VDAGENTD_CLIPBOARD_DATA:
         vdagent_x11_clipboard_data(x11, header->opaque, data, header->size);
+        /* vdagent_x11_clipboard_data takes ownership of the data (or frees
+           it immediately) */
         break;
     case VDAGENTD_CLIPBOARD_RELEASE:
         vdagent_x11_clipboard_release(x11);
+        free(data);
         break;
     default:
         if (verbose)
             fprintf(logfile, "Unknown message from vdagentd type: %d\n",
                     header->type);
+        free(data);
     }
 }
 
diff --git a/vdagentd.c b/vdagentd.c
index a88bdf5..6365552 100644
--- a/vdagentd.c
+++ b/vdagentd.c
@@ -466,7 +466,7 @@ void agent_disconnect(struct udscs_connection *conn)
 }
 
 void agent_read_complete(struct udscs_connection **connp,
-    struct udscs_message_header *header, const uint8_t *data)
+    struct udscs_message_header *header, uint8_t *data)
 {
     struct agent_data *agent_data = udscs_get_user_data(*connp);
 
@@ -497,6 +497,7 @@ void agent_read_complete(struct udscs_connection **connp,
         fprintf(logfile, "unknown message from vdagent: %u, ignoring\n",
                 header->type);
     }
+    free(data);
 }
 
 /* main */