rsvg_handle_new_from_data(): Port the implementation to Rust

2 files changed, 35 insertions, 0 deletions

diff --git a/rsvg_internals/src/handle.rs b/rsvg_internals/src/handle.rs
index 900645f7..6a053f25 100644
--- a/rsvg_internals/src/handle.rs
+++ b/rsvg_internals/src/handle.rs
@@ -1,3 +1,4 @@
+use std;
 use std::cell::{Cell, Ref, RefCell};
 use std::ffi::CString;
 use std::mem;
@@ -1239,3 +1240,36 @@ pub unsafe extern "C" fn rsvg_handle_rust_new_from_stream_sync(
         }
     }
 }
+
+#[no_mangle]
+pub unsafe extern "C" fn rsvg_handle_rust_new_from_data(
+    data: *mut u8,
+    len: usize,
+    error: *mut *mut glib_sys::GError,
+) -> *mut RsvgHandle {
+    // We create the MemoryInputStream without the gtk-rs binding because of this:
+    //
+    // - The binding doesn't provide _new_from_data().  All of the binding's ways to
+    // put data into a MemoryInputStream involve copying the data buffer.
+    //
+    // - We can't use glib::Bytes from the binding either, for the same reason.
+    //
+    // - For now, we are using the other C-visible constructor, so we need a raw pointer to the
+    //   stream, anyway.
+
+    assert!(len <= std::isize::MAX as usize);
+    let len = len as isize;
+
+    let raw_stream = gio_sys::g_memory_input_stream_new_from_data(data, len, None);
+
+    let ret = rsvg_handle_rust_new_from_stream_sync(
+        raw_stream as *mut _,
+        ptr::null_mut(), // base_file
+        0,               // flags
+        ptr::null_mut(), // cancellable
+        error,
+    );
+
+    gobject_sys::g_object_unref(raw_stream as *mut _);
+    ret
+}
diff --git a/rsvg_internals/src/lib.rs b/rsvg_internals/src/lib.rs
index e2ccf936..c1c2ff44 100644
--- a/rsvg_internals/src/lib.rs
+++ b/rsvg_internals/src/lib.rs
@@ -54,6 +54,7 @@ pub use handle::{
     rsvg_handle_rust_get_position_sub,
     rsvg_handle_rust_has_sub,
     rsvg_handle_rust_new,
+    rsvg_handle_rust_new_from_data,
     rsvg_handle_rust_new_from_gfile_sync,
     rsvg_handle_rust_new_from_stream_sync,
     rsvg_handle_rust_read_stream_sync,