Make sources thread-safe

1 files changed, 16 insertions, 3 deletions

diff --git a/src/backend_librsvg.c b/src/backend_librsvg.c
index 083fb9c..c9a91ff 100644
--- a/src/backend_librsvg.c
+++ b/src/backend_librsvg.c
@@ -21,6 +21,7 @@ struct private {
 
 static void source_free(struct imv_source *src)
 {
+  pthread_mutex_lock(&src->busy);
   free(src->name);
   src->name = NULL;
 
@@ -28,6 +29,8 @@ static void source_free(struct imv_source *src)
   free(private);
   src->private = NULL;
 
+  pthread_mutex_unlock(&src->busy);
+  pthread_mutex_destroy(&src->busy);
   free(src);
 }
 
@@ -57,6 +60,7 @@ static void report_error(struct imv_source *src)
   msg.bitmap = NULL;
   msg.error = "Internal error";
 
+  pthread_mutex_unlock(&src->busy);
   src->callback(&msg);
 }
 
@@ -76,11 +80,17 @@ static void send_bitmap(struct imv_source *src, GdkPixbuf *bitmap)
   msg.frametime = 0;
   msg.error = NULL;
 
+  pthread_mutex_unlock(&src->busy);
   src->callback(&msg);
 }
 
-static void load_image(struct imv_source *src)
+static int load_image(struct imv_source *src)
 {
+  /* Don't run if this source is already active */
+  if (pthread_mutex_trylock(&src->busy)) {
+    return -1;
+  }
+
   RsvgHandle *handle = NULL;
   GError *error = NULL;
 
@@ -95,7 +105,7 @@ static void load_image(struct imv_source *src)
 
   if (!handle) {
     report_error(src);
-    return;
+    return -1;
   }
 
   RsvgDimensionData dim;
@@ -107,11 +117,12 @@ static void load_image(struct imv_source *src)
   if (!buf) {
     rsvg_handle_close(handle, &error);
     report_error(src);
-    return;
+    return -1;
   }
 
   rsvg_handle_close(handle, &error);
   send_bitmap(src, buf);
+  return 0;
 }
 
 static enum backend_result open_path(const char *path, struct imv_source **src)
@@ -141,6 +152,7 @@ static enum backend_result open_path(const char *path, struct imv_source **src)
   source->height = 1024;
   source->num_frames = 1;
   source->next_frame = 1;
+  pthread_mutex_init(&source->busy, NULL);
   source->load_first_frame = &load_image;
   source->load_next_frame = NULL;
   source->free = &source_free;
@@ -173,6 +185,7 @@ static enum backend_result open_memory(void *data, size_t len, struct imv_source
   source->height = 1024;
   source->num_frames = 1;
   source->next_frame = 1;
+  pthread_mutex_init(&source->busy, NULL);
   source->load_first_frame = &load_image;
   source->load_next_frame = NULL;
   source->free = &source_free;