[librsvg] LoadState: move the RsvgHandlePrivate.hstate field to Rust

[Federico Mena Quintero <federico src gnome org>]

commit 8c117a4e4438405140892dbda08158833678cd57
Author: Federico Mena Quintero <federico gnome org>
Date:   Mon Dec 17 18:23:49 2018 -0600

    LoadState: move the RsvgHandlePrivate.hstate field to Rust

 librsvg/rsvg-handle.c        | 38 +++++++++++++++++++++-----------------
 librsvg/rsvg-private.h       |  2 --
 rsvg_internals/src/handle.rs | 28 ++++++++++++++++++++++++++++
 rsvg_internals/src/lib.rs    |  2 ++
 4 files changed, 51 insertions(+), 19 deletions(-)
---
diff --git a/librsvg/rsvg-handle.c b/librsvg/rsvg-handle.c
index 1832c131..e15e9aa6 100644
--- a/librsvg/rsvg-handle.c
+++ b/librsvg/rsvg-handle.c
@@ -143,6 +143,8 @@ extern gboolean rsvg_handle_rust_node_is_root(RsvgHandleRust *raw_handle, RsvgNo
 extern void rsvg_handle_rust_steal_result (RsvgHandleRust *raw_handle, RsvgXmlState *xml);
 extern guint rsvg_handle_rust_get_flags (RsvgHandleRust *raw_handle);
 extern void rsvg_handle_rust_set_flags (RsvgHandleRust *raw_handle, guint flags);
+extern void rsvg_handle_rust_set_load_state (RsvgHandleRust *raw_handle, RsvgHandleState state);
+extern RsvgHandleState rsvg_handle_rust_get_load_state (RsvgHandleRust *raw_handle);
 
 /* Implemented in rsvg_internals/src/xml.rs */
 extern void rsvg_xml_state_free (RsvgXmlState *xml);
@@ -203,8 +205,6 @@ rsvg_handle_init (RsvgHandle * self)
 {
     self->priv = rsvg_handle_get_instance_private (self);
 
-    self->priv->hstate = RSVG_HANDLE_STATE_START;
-
     self->priv->in_loop = FALSE;
 
     self->priv->is_testing = FALSE;
@@ -674,23 +674,26 @@ gboolean
 rsvg_handle_write (RsvgHandle *handle, const guchar *buf, gsize count, GError **error)
 {
     RsvgHandlePrivate *priv;
+    RsvgHandleState lstate;
 
     g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
     rsvg_return_val_if_fail (handle, FALSE, error);
 
     priv = handle->priv;
 
-    g_return_val_if_fail (priv->hstate == RSVG_HANDLE_STATE_START
-                          || priv->hstate == RSVG_HANDLE_STATE_LOADING,
+    lstate = rsvg_handle_rust_get_load_state (priv->rust_handle);
+
+    g_return_val_if_fail (lstate == RSVG_HANDLE_STATE_START
+                          || lstate == RSVG_HANDLE_STATE_LOADING,
                           FALSE);
 
-    if (priv->hstate == RSVG_HANDLE_STATE_START) {
-        priv->hstate = RSVG_HANDLE_STATE_LOADING;
+    if (lstate == RSVG_HANDLE_STATE_START) {
+        rsvg_handle_rust_set_load_state (priv->rust_handle, RSVG_HANDLE_STATE_LOADING);
         priv->load = rsvg_load_new (rsvg_xml_state_new (handle),
                                     rsvg_handle_rust_get_flags (priv->rust_handle));
     }
 
-    g_assert (priv->hstate == RSVG_HANDLE_STATE_LOADING);
+    g_assert (rsvg_handle_rust_get_load_state (priv->rust_handle) == RSVG_HANDLE_STATE_LOADING);
 
     rsvg_load_write (priv->load, buf, count);
 
@@ -710,9 +713,9 @@ finish_load (RsvgHandle *handle, RsvgXmlState *xml, gboolean was_successful, GEr
     }
 
     if (was_successful) {
-        handle->priv->hstate = RSVG_HANDLE_STATE_CLOSED_OK;
+        rsvg_handle_rust_set_load_state (handle->priv->rust_handle, RSVG_HANDLE_STATE_CLOSED_OK);
     } else {
-        handle->priv->hstate = RSVG_HANDLE_STATE_CLOSED_ERROR;
+        rsvg_handle_rust_set_load_state (handle->priv->rust_handle, RSVG_HANDLE_STATE_CLOSED_ERROR);
     }
 
     return was_successful;
@@ -745,10 +748,10 @@ rsvg_handle_close (RsvgHandle *handle, GError **error)
 
     priv = handle->priv;
 
-    switch (priv->hstate) {
+    switch (rsvg_handle_rust_get_load_state (priv->rust_handle)) {
     case RSVG_HANDLE_STATE_START:
         g_set_error (error, RSVG_ERROR, RSVG_ERROR_FAILED, _("no data passed to parser"));
-        priv->hstate = RSVG_HANDLE_STATE_CLOSED_ERROR;
+        rsvg_handle_rust_set_load_state (priv->rust_handle, RSVG_HANDLE_STATE_CLOSED_ERROR);
         result = FALSE;
         break;
 
@@ -773,8 +776,8 @@ rsvg_handle_close (RsvgHandle *handle, GError **error)
         g_assert_not_reached ();
     }
 
-    g_assert (priv->hstate == RSVG_HANDLE_STATE_CLOSED_OK
-              || priv->hstate == RSVG_HANDLE_STATE_CLOSED_ERROR);
+    g_assert (rsvg_handle_rust_get_load_state (priv->rust_handle) == RSVG_HANDLE_STATE_CLOSED_OK
+              || rsvg_handle_rust_get_load_state (priv->rust_handle) == RSVG_HANDLE_STATE_CLOSED_ERROR);
 
     return result;
 }
@@ -816,9 +819,10 @@ rsvg_handle_read_stream_sync (RsvgHandle   *handle,
 
     priv = handle->priv;
 
-    g_return_val_if_fail (priv->hstate == RSVG_HANDLE_STATE_START, FALSE);
+    g_return_val_if_fail (rsvg_handle_rust_get_load_state (priv->rust_handle) == RSVG_HANDLE_STATE_START,
+                          FALSE);
 
-    priv->hstate = RSVG_HANDLE_STATE_LOADING;
+    rsvg_handle_rust_set_load_state (priv->rust_handle, RSVG_HANDLE_STATE_LOADING);
 
     xml = rsvg_xml_state_new (handle);
     read_successfully = rsvg_xml_state_load_from_possibly_compressed_stream (
@@ -890,7 +894,7 @@ get_base_uri_from_filename (const gchar * filename)
 static gboolean
 is_at_start_for_setting_base_file (RsvgHandle *handle)
 {
-    if (handle->priv->hstate == RSVG_HANDLE_STATE_START) {
+    if (rsvg_handle_rust_get_load_state (handle->priv->rust_handle) == RSVG_HANDLE_STATE_START) {
         return TRUE;
     } else {
         g_warning ("Please set the base file or URI before loading any data into RsvgHandle");
@@ -1070,7 +1074,7 @@ rsvg_handle_create_drawing_ctx(RsvgHandle *handle,
 static gboolean
 is_loaded (RsvgHandle *handle)
 {
-    switch (handle->priv->hstate) {
+    switch (rsvg_handle_rust_get_load_state (handle->priv->rust_handle)) {
     case RSVG_HANDLE_STATE_START:
         g_warning ("RsvgHandle has not been loaded");
         return FALSE;
diff --git a/librsvg/rsvg-private.h b/librsvg/rsvg-private.h
index 57046e1e..9d9ed259 100644
--- a/librsvg/rsvg-private.h
+++ b/librsvg/rsvg-private.h
@@ -89,8 +89,6 @@ typedef struct RsvgLoad RsvgLoad;
 typedef struct RsvgHandleRust RsvgHandleRust;
 
 struct RsvgHandlePrivate {
-    RsvgHandleState hstate;
-
     RsvgLoad *load;
 
     RsvgSizeFunc size_func;
diff --git a/rsvg_internals/src/handle.rs b/rsvg_internals/src/handle.rs
index a14dfdfa..c6af775a 100644
--- a/rsvg_internals/src/handle.rs
+++ b/rsvg_internals/src/handle.rs
@@ -44,11 +44,21 @@ pub struct LoadOptions {
     pub keep_image_data: bool,
 }
 
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub enum LoadState {
+    Start,
+    Loading,
+    ClosedOk,
+    ClosedError,
+}
+
 pub struct Handle {
     dpi: Dpi,
     base_url: RefCell<Option<Url>>,
     svg: RefCell<Option<Svg>>,
     load_options: Cell<LoadOptions>,
+    load_state: Cell<LoadState>,
 }
 
 impl Handle {
@@ -58,6 +68,7 @@ impl Handle {
             base_url: RefCell::new(None),
             svg: RefCell::new(None),
             load_options: Cell::new(LoadOptions::default()),
+            load_state: Cell::new(LoadState::Start),
         }
     }
 }
@@ -570,3 +581,20 @@ pub unsafe extern "C" fn rsvg_handle_rust_set_flags(raw_handle: *const Handle, f
 
     rhandle.load_options.set(LoadOptions::from_flags(flags));
 }
+
+#[no_mangle]
+pub unsafe extern "C" fn rsvg_handle_rust_get_load_state(raw_handle: *const Handle) -> LoadState {
+    let rhandle = &*raw_handle;
+
+    rhandle.load_state.get()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn rsvg_handle_rust_set_load_state(
+    raw_handle: *const Handle,
+    load_state: LoadState,
+) {
+    let rhandle = &*raw_handle;
+
+    rhandle.load_state.set(load_state)
+}
diff --git a/rsvg_internals/src/lib.rs b/rsvg_internals/src/lib.rs
index a7950025..f29483b9 100644
--- a/rsvg_internals/src/lib.rs
+++ b/rsvg_internals/src/lib.rs
@@ -53,6 +53,7 @@ pub use handle::{
     rsvg_handle_rust_get_dpi_x,
     rsvg_handle_rust_get_dpi_y,
     rsvg_handle_rust_get_flags,
+    rsvg_handle_rust_get_load_state,
     rsvg_handle_rust_get_root,
     rsvg_handle_rust_new,
     rsvg_handle_rust_node_is_root,
@@ -60,6 +61,7 @@ pub use handle::{
     rsvg_handle_rust_set_dpi_x,
     rsvg_handle_rust_set_dpi_y,
     rsvg_handle_rust_set_flags,
+    rsvg_handle_rust_set_load_state,
     rsvg_handle_rust_steal_result,
 };