librsvg source for verification 2026-05-22

gdk-pixbuf-loader/src/lib.rs

@@ -0,0 +1,378 @@
+use std::ptr::null_mut;
+
+use gdk_pixbuf::ffi::{
+    GDK_PIXBUF_FORMAT_SCALABLE, GDK_PIXBUF_FORMAT_THREADSAFE, GdkPixbufFormat, GdkPixbufModule,
+    GdkPixbufModulePattern, GdkPixbufModulePreparedFunc, GdkPixbufModuleSizeFunc,
+    GdkPixbufModuleUpdatedFunc,
+};
+
+use std::ffi::{c_char, c_int, c_uint};
+
+use glib::Bytes;
+use glib::ffi::{GDestroyNotify, GError, gboolean, gpointer};
+use glib::prelude::*;
+use glib::translate::*;
+
+use gio::MemoryInputStream;
+use gio::ffi::{GCancellable, GFile, GInputStream};
+use gio::prelude::*;
+
+use glib::gstr;
+
+type RSvgHandle = glib::gobject_ffi::GObject;
+
+type RsvgSizeFunc = Option<
+    unsafe extern "C" fn(inout_width: *mut c_int, inout_height: *mut c_int, user_data: gpointer),
+>;
+
+#[link(name = "rsvg-2")]
+unsafe extern "C" {
+    fn rsvg_handle_new_from_stream_sync(
+        input_stream: *mut GInputStream,
+        base_file: *mut GFile,
+        flags: u32,
+        cancellable: *mut GCancellable,
+        error: *mut *mut GError,
+    ) -> *mut RSvgHandle;
+
+    fn rsvg_handle_get_pixbuf_and_error(
+        handle: *mut RSvgHandle,
+        error: *mut *mut GError,
+    ) -> *mut gdk_pixbuf::ffi::GdkPixbuf;
+
+    fn rsvg_handle_set_size_callback(
+        handle: *mut RSvgHandle,
+        size_func: RsvgSizeFunc,
+        user_data: gpointer,
+        destroy_notify: GDestroyNotify,
+    );
+}
+
+struct SvgContext {
+    size_func: GdkPixbufModuleSizeFunc,
+    prep_func: GdkPixbufModulePreparedFunc,
+    update_func: GdkPixbufModuleUpdatedFunc,
+    user_data: gpointer,
+    stream: MemoryInputStream,
+}
+
+unsafe extern "C" fn begin_load(
+    size_func: GdkPixbufModuleSizeFunc,
+    prep_func: GdkPixbufModulePreparedFunc,
+    update_func: GdkPixbufModuleUpdatedFunc,
+    user_data: gpointer,
+    error: *mut *mut GError,
+) -> gpointer {
+    if !error.is_null() {
+        *error = null_mut();
+    }
+
+    let stream = MemoryInputStream::new();
+    let ctx = Box::new(SvgContext {
+        size_func,
+        prep_func,
+        update_func,
+        user_data,
+        stream,
+    });
+
+    Box::into_raw(ctx) as gpointer
+}
+
+unsafe extern "C" fn load_increment(
+    user_data: gpointer,
+    buffer: *const u8,
+    size: c_uint,
+    error: *mut *mut GError,
+) -> gboolean {
+    if !error.is_null() {
+        *error = null_mut();
+    }
+
+    let ctx = user_data as *mut SvgContext;
+
+    let data = std::slice::from_raw_parts(buffer, size as usize);
+    (*ctx).stream.add_bytes(&Bytes::from(data));
+    true.into_glib()
+}
+
+unsafe extern "C" fn stop_load(user_data: gpointer, error: *mut *mut GError) -> gboolean {
+    let ctx = Box::from_raw(user_data as *mut SvgContext);
+    if !error.is_null() {
+        *error = null_mut();
+    }
+
+    let mut local_error = null_mut::<GError>();
+
+    let handle = {
+        let raw_handle = rsvg_handle_new_from_stream_sync(
+            ctx.stream.upcast_ref::<gio::InputStream>().to_glib_none().0,
+            null_mut(), // base_file
+            0,
+            null_mut(), // cancellable
+            &mut local_error,
+        );
+        if !local_error.is_null() {
+            if !error.is_null() {
+                *error = local_error;
+            }
+            return false.into_glib();
+        }
+
+        glib::Object::from_glib_full(raw_handle)
+    };
+
+    rsvg_handle_set_size_callback(handle.as_ptr(), ctx.size_func, ctx.user_data, None);
+
+    let pixbuf = {
+        let p = rsvg_handle_get_pixbuf_and_error(handle.as_ptr(), &mut local_error);
+        if !local_error.is_null() {
+            if !error.is_null() {
+                *error = local_error;
+            }
+            return false.into_glib();
+        }
+
+        gdk_pixbuf::Pixbuf::from_glib_full(p)
+    };
+
+    let w = pixbuf.width();
+    let h = pixbuf.height();
+
+    if let Some(prep_func) = ctx.prep_func {
+        prep_func(pixbuf.to_glib_none().0, null_mut(), ctx.user_data);
+    }
+    if let Some(update_func) = ctx.update_func {
+        update_func(pixbuf.to_glib_none().0, 0, 0, w, h, ctx.user_data);
+    }
+
+    true.into_glib()
+}
+
+#[unsafe(no_mangle)]
+extern "C" fn fill_vtable(module: &mut GdkPixbufModule) {
+    module.begin_load = Some(begin_load);
+    module.stop_load = Some(stop_load);
+    module.load_increment = Some(load_increment);
+}
+
+const SIGNATURE: [GdkPixbufModulePattern; 3] = [
+    GdkPixbufModulePattern {
+        prefix: gstr!(" <svg").as_ptr() as *mut c_char,
+        mask: gstr!("*    ").as_ptr() as *mut c_char,
+        relevance: 100,
+    },
+    GdkPixbufModulePattern {
+        prefix: gstr!(" <!DOCTYPE svg").as_ptr() as *mut c_char,
+        mask: gstr!("*             ").as_ptr() as *mut c_char,
+        relevance: 100,
+    },
+    GdkPixbufModulePattern {
+        prefix: null_mut(),
+        mask: null_mut(),
+        relevance: 0,
+    },
+];
+
+const MIME_TYPES: [*const c_char; 7] = [
+    gstr!("image/svg+xml").as_ptr(),
+    gstr!("image/svg").as_ptr(),
+    gstr!("image/svg-xml").as_ptr(),
+    gstr!("image/vnd.adobe.svg+xml").as_ptr(),
+    gstr!("text/xml-svg").as_ptr(),
+    gstr!("image/svg+xml-compressed").as_ptr(),
+    std::ptr::null(),
+];
+
+const EXTENSIONS: [*const c_char; 4] = [
+    gstr!("svg").as_ptr(),
+    gstr!("svgz").as_ptr(),
+    gstr!("svg.gz").as_ptr(),
+    std::ptr::null(),
+];
+
+#[unsafe(no_mangle)]
+extern "C" fn fill_info(info: &mut GdkPixbufFormat) {
+    info.name = gstr!("svg").as_ptr() as *mut c_char;
+    info.signature = SIGNATURE.as_ptr() as *mut GdkPixbufModulePattern;
+    info.description = gstr!("Scalable Vector Graphics").as_ptr() as *mut c_char; //TODO: Gettext this
+    info.mime_types = MIME_TYPES.as_ptr() as *mut *mut c_char;
+    info.extensions = EXTENSIONS.as_ptr() as *mut *mut c_char;
+    info.flags = GDK_PIXBUF_FORMAT_SCALABLE | GDK_PIXBUF_FORMAT_THREADSAFE;
+    info.license = gstr!("LGPL").as_ptr() as *mut c_char;
+}
+
+#[cfg(test)]
+mod tests {
+    use gdk_pixbuf::ffi::{
+        GDK_PIXBUF_FORMAT_SCALABLE, GDK_PIXBUF_FORMAT_THREADSAFE, GdkPixbufFormat,
+    };
+    use glib::translate::IntoGlib;
+
+    use crate::{EXTENSIONS, MIME_TYPES};
+    use std::ffi::c_char;
+    use std::ptr::null_mut;
+
+    fn pb_format_new() -> GdkPixbufFormat {
+        let mut info = super::GdkPixbufFormat {
+            name: null_mut(),
+            signature: null_mut(),
+            description: null_mut(),
+            mime_types: null_mut(),
+            extensions: null_mut(),
+            flags: 0,
+            license: null_mut(),
+            disabled: false.into_glib(),
+            domain: null_mut(),
+        };
+
+        super::fill_info(&mut info);
+        info
+    }
+
+    #[test]
+    fn fill_info() {
+        let info = pb_format_new();
+
+        assert!(!info.name.is_null());
+        assert!(!info.signature.is_null());
+        assert!(!info.description.is_null());
+        assert!(!info.mime_types.is_null());
+        assert!(!info.extensions.is_null());
+        assert_eq!(
+            info.flags,
+            GDK_PIXBUF_FORMAT_SCALABLE | GDK_PIXBUF_FORMAT_THREADSAFE
+        );
+        assert!(!info.license.is_null());
+    }
+
+    fn check_null_terminated_arr_cstrings(arr: &[*const c_char]) {
+        let n_strings = arr
+            .iter()
+            .filter(|e| !e.is_null())
+            .map(|e| {
+                if !e.is_null() {
+                    assert!(!unsafe { std::ffi::CStr::from_ptr(*e) }.is_empty())
+                }
+            })
+            .count(); // Count all non_null items
+
+        // Ensure last item is null and is the only null item
+        assert_eq!(n_strings, arr.len() - 1);
+        assert!(arr.last().unwrap().is_null());
+    }
+
+    #[test]
+    fn extensions_bounds() {
+        check_null_terminated_arr_cstrings(&EXTENSIONS);
+    }
+
+    #[test]
+    fn mime_bounds() {
+        check_null_terminated_arr_cstrings(&MIME_TYPES)
+    }
+
+    #[test]
+    fn signature() {
+        let info = pb_format_new();
+        unsafe {
+            for i in 0..2 {
+                let ptr = info.signature.offset(i);
+                if i == 2 {
+                    assert!((*ptr).prefix.is_null());
+                    continue;
+                } else {
+                    assert!(!(*ptr).prefix.is_null());
+                    if !(*ptr).mask.is_null() {
+                        // Mask can be null
+                        let prefix = std::ffi::CStr::from_ptr((*ptr).prefix).to_bytes();
+                        let mask = std::ffi::CStr::from_ptr((*ptr).mask).to_bytes();
+                        assert_eq!(prefix.len(), mask.len());
+                    }
+                    // Relevance must be 0 to 100
+                    assert!((*ptr).relevance >= 0);
+                    assert!((*ptr).relevance <= 100);
+                }
+            }
+        }
+    }
+
+    const SVG_DATA: &str = r#"<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+                                    <svg
+                                    width="100px"
+                                    height="150px"
+                                    viewBox="0 0 26.458333 26.458333"
+                                    version="1.1"
+                                    id="svg5"
+                                    xmlns="http://www.w3.org/2000/svg"
+                                    xmlns:svg="http://www.w3.org/2000/svg">
+                                    <rect
+                                        style="fill:#aa1144;stroke-width:0.0344347"
+                                        width="26.458332"
+                                        height="39.6875"
+                                        x="4.691162e-07"
+                                        y="-6.6145835"
+                                        id="rect2" />
+                                    </svg>
+    "#;
+
+    #[test]
+    fn minimal_svg() {
+        unsafe extern "C" fn prep_cb(
+            pb: *mut gdk_pixbuf::ffi::GdkPixbuf,
+            pba: *mut gdk_pixbuf::ffi::GdkPixbufAnimation,
+            user_data: *mut std::ffi::c_void,
+        ) {
+            assert!(user_data.is_null());
+            assert!(pba.is_null());
+
+            let w = gdk_pixbuf::ffi::gdk_pixbuf_get_width(pb);
+            let h = gdk_pixbuf::ffi::gdk_pixbuf_get_height(pb);
+            let stride = gdk_pixbuf::ffi::gdk_pixbuf_get_rowstride(pb);
+            assert_eq!(w, 100);
+            assert_eq!(h, 150);
+
+            let pixels = gdk_pixbuf::ffi::gdk_pixbuf_get_pixels(pb);
+
+            // Upper left pixel #aa1144ff
+            assert_eq!(*pixels, 0xaa);
+            assert_eq!(*pixels.offset(1), 0x11);
+            assert_eq!(*pixels.offset(2), 0x44);
+            assert_eq!(*pixels.offset(3), 0xff);
+
+            // Bottom left pixel
+            assert_eq!(*pixels.offset((stride * (h - 1)) as isize), 0xaa);
+            assert_eq!(*pixels.offset((stride * (h - 1)) as isize + 1), 0x11);
+            assert_eq!(*pixels.offset((stride * (h - 1)) as isize + 2), 0x44);
+            assert_eq!(*pixels.offset((stride * (h - 1)) as isize + 3), 0xff);
+
+            // Bottom right pixel
+            assert_eq!(
+                *pixels.offset((stride * (h - 1)) as isize + (w as isize - 1) * 4),
+                0xaa
+            );
+            assert_eq!(
+                *pixels.offset((stride * (h - 1)) as isize + (w as isize - 1) * 4 + 1),
+                0x11
+            );
+            assert_eq!(
+                *pixels.offset((stride * (h - 1)) as isize + (w as isize - 1) * 4 + 2),
+                0x44
+            );
+            assert_eq!(
+                *pixels.offset((stride * (h - 1)) as isize + (w as isize - 1) * 4 + 3),
+                0xff
+            );
+        }
+        unsafe {
+            let ctx = crate::begin_load(None, Some(prep_cb), None, null_mut(), null_mut());
+            assert_ne!(ctx, null_mut());
+
+            let inc =
+                crate::load_increment(ctx, SVG_DATA.as_ptr(), SVG_DATA.len() as u32, null_mut());
+            assert_ne!(inc, 0);
+
+            crate::stop_load(ctx, null_mut());
+        }
+    }
+}