Validate exported 3MF files

tools/export-validator/src/ffi.rs

@@ -0,0 +1,62 @@
+//! Minimal foreign function interface for lib3mf
+//!
+//! See these header files for more information:
+//! - https://github.com/3MFConsortium/lib3mf/blob/master/Autogenerated/Bindings/C/lib3mf.h
+//! - https://github.com/3MFConsortium/lib3mf/blob/master/Autogenerated/Bindings/C/lib3mf_types.h
+
+use std::{ffi::c_void, os::raw::c_char};
+
+pub type Model = Handle;
+pub type Object = Handle;
+pub type Reader = Handle;
+
+pub type ObjectIterator = Handle;
+pub type ResourceIterator = Handle;
+
+pub type Handle = *const c_void;
+pub type Result = i32;
+
+extern "C" {
+    pub fn lib3mf_createmodel(pModel: *mut Model) -> Result;
+
+    pub fn lib3mf_model_queryreader(
+        pModel: Model,
+        pReaderClass: *const c_char,
+        pReaderInstance: *mut Reader,
+    ) -> Result;
+
+    pub fn lib3mf_reader_setstrictmodeactive(
+        pReader: Reader,
+        bStrictModeActive: bool,
+    ) -> Result;
+
+    pub fn lib3mf_reader_readfromfile(
+        pReader: Reader,
+        pFilename: *const c_char,
+    ) -> Result;
+
+    pub fn lib3mf_reader_getwarningcount(
+        pReader: Reader,
+        pCount: *mut u32,
+    ) -> Result;
+
+    pub fn lib3mf_model_getobjects(
+        pModel: Model,
+        pResourceIterator: *mut ObjectIterator,
+    ) -> Result;
+
+    pub fn lib3mf_resourceiterator_movenext(
+        pResourceIterator: ResourceIterator,
+        pHasNext: *mut bool,
+    ) -> Result;
+
+    pub fn lib3mf_objectiterator_getcurrentobject(
+        pObjectIterator: ObjectIterator,
+        pResource: *mut Object,
+    ) -> Result;
+
+    pub fn lib3mf_object_isvalid(
+        pObject: Object,
+        pIsValid: &mut bool,
+    ) -> Result;
+}

tools/export-validator/src/main.rs

@@ -1,6 +1,8 @@
-use std::{fs, process::Command};
+mod ffi;
 
-use anyhow::{anyhow, bail};
+use std::{ffi::CString, fs, process::Command, ptr};
+
+use anyhow::{anyhow, bail, Context as _};
 
 fn main() -> anyhow::Result<()> {
     for model in fs::read_dir("models")? {
@@ -24,6 +26,118 @@ fn main() -> anyhow::Result<()> {
                 {exit_status}"
             );
         }
+
+        // Presumably we're using the library in the way it's intended, so this
+        // might be sound?
+        unsafe {
+            validate_model(&export_file).with_context(|| {
+                format!("Could not validate model `{model}`")
+            })?;
+        }
+    }
+
+    Ok(())
+}
+
+unsafe fn validate_model(file: &str) -> anyhow::Result<()> {
+    let mut model = ptr::null();
+
+    let result = ffi::lib3mf_createmodel(&mut model);
+    if result != 0 {
+        bail!("Failed to create model; error code: {result}");
+    }
+
+    let mut reader = ptr::null();
+    let reader_class = CString::new("3mf")?;
+
+    let result = ffi::lib3mf_model_queryreader(
+        model,
+        reader_class.as_ptr(),
+        &mut reader,
+    );
+    if result != 0 {
+        bail!("Failed to query reader; error code: {result}");
+    }
+
+    let result = ffi::lib3mf_reader_setstrictmodeactive(reader, true);
+    if result != 0 {
+        bail!("Failed to set strict mode; error code: {result}");
+    }
+
+    let path = CString::new(file)?;
+
+    let result = ffi::lib3mf_reader_readfromfile(reader, path.as_ptr());
+    if result != 0 {
+        bail!("Failed to read model; error code: {result}");
+    }
+
+    let mut num_warnings = 0;
+
+    let result = ffi::lib3mf_reader_getwarningcount(reader, &mut num_warnings);
+    if result != 0 {
+        bail!("Failed to get number of warnings; error code: {result}");
+    }
+
+    if num_warnings > 0 {
+        bail!(
+            "Warnings while reading model; number of warnings: {num_warnings}"
+        );
+    }
+
+    let mut object_iterator = ptr::null();
+
+    let result = ffi::lib3mf_model_getobjects(model, &mut object_iterator);
+    if result != 0 {
+        bail!("Failed to get object iterator; error code: {result}");
+    }
+
+    loop {
+        let mut has_next = false;
+
+        let result = ffi::lib3mf_resourceiterator_movenext(
+            object_iterator,
+            &mut has_next,
+        );
+        if result != 0 {
+            bail!(
+                "Failed to move iterator to next object; error code: {result}"
+            );
+        }
+
+        if !has_next {
+            break;
+        }
+
+        let mut object = ptr::null();
+
+        let result = ffi::lib3mf_objectiterator_getcurrentobject(
+            object_iterator,
+            &mut object,
+        );
+        if result != 0 {
+            bail!("Failed to get object; error code: {result}");
+        }
+
+        let mut is_valid = false;
+
+        let result = ffi::lib3mf_object_isvalid(object, &mut is_valid);
+        if result != 0 {
+            bail!(
+                "Failed to determine if object is valid; error code: {result}"
+            );
+        }
+
+        if !is_valid {
+            // Yes, this error message is a bit sparse. If anyone is interested
+            // in expanding this program, you're welcome to do that.
+            //
+            // However, the point here is to fail the CI build if something is
+            // wrong. Once you know *that* the file is wrong, you can use an
+            // existing validator to get more information. This is probably more
+            // productive than expending effort to turn this into the perfect
+            // validator.
+            bail!("Object is not valid");
+        }
     }
 
     Ok(())