fix(engine): check Wavefront obj statement argument counts

1 files changed, 80 insertions, 7 deletions

diff --git a/engine/src/file_format/wavefront/obj.rs b/engine/src/file_format/wavefront/obj.rs
index 29fc985..7dab37c 100644
--- a/engine/src/file_format/wavefront/obj.rs
+++ b/engine/src/file_format/wavefront/obj.rs
@@ -47,13 +47,29 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 return None;
             }
 
+            if statement.arguments.len() == 4 {
+                return Some(Err(Error::UnsupportedArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
+            if statement.arguments.len() > 4 {
+                return Some(Err(Error::InvalidArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
             let x = try_option!(statement.get_float_arg(0, *line_no));
             let y = try_option!(statement.get_float_arg(1, *line_no));
             let z = try_option!(statement.get_float_arg(2, *line_no));
 
             Some(Ok(Vec3 { x, y, z }))
         })
-        .collect::<Result<Vec<_>, _>>()?;
+        .collect::<Result<Vec<_>, Error>>()?;
 
     let texture_positions = statements
         .iter()
@@ -62,13 +78,28 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 return None;
             }
 
+            if statement.arguments.len() == 3 {
+                return Some(Err(Error::UnsupportedArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
+            if statement.arguments.len() > 3 {
+                return Some(Err(Error::InvalidArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
             let u = try_option!(statement.get_float_arg(0, *line_no));
             let v = try_option!(statement.get_float_arg(1, *line_no));
-            // let w = try_option!(statement.get_float_arg(2, *line_no));
 
             Some(Ok(Vec2 { x: u, y: v }))
         })
-        .collect::<Result<Vec<_>, _>>()?;
+        .collect::<Result<Vec<_>, Error>>()?;
 
     let vertex_normals = statements
         .iter()
@@ -77,13 +108,21 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 return None;
             }
 
+            if statement.arguments.len() > 3 {
+                return Some(Err(Error::InvalidArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
             let i = try_option!(statement.get_float_arg(0, *line_no));
             let j = try_option!(statement.get_float_arg(1, *line_no));
             let k = try_option!(statement.get_float_arg(2, *line_no));
 
             Some(Ok(Vec3 { x: i, y: j, z: k }))
         })
-        .collect::<Result<Vec<_>, _>>()?;
+        .collect::<Result<Vec<_>, Error>>()?;
 
     let material_specifiers = statements
         .iter()
@@ -92,6 +131,14 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 return None;
             }
 
+            if statement.arguments.len() > 1 {
+                return Some(Err(Error::InvalidArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
             let material_name = try_option!(statement.get_text_arg(0, *line_no));
 
             Some(Ok(MaterialSpecifier {
@@ -99,7 +146,7 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 line_no: *line_no,
             }))
         })
-        .collect::<Result<Vec<_>, _>>()?;
+        .collect::<Result<Vec<_>, Error>>()?;
 
     let faces = statements
         .iter()
@@ -108,6 +155,14 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 return None;
             }
 
+            if statement.arguments.len() > 3 {
+                return Some(Err(Error::UnsupportedArgumentCount {
+                    keyword: statement.keyword.to_string(),
+                    arg_count: statement.arguments.len(),
+                    line_no: *line_no,
+                }));
+            }
+
             let vertex_a = try_option!(statement.get_triplet_arg(0, *line_no)).into();
             let vertex_b = try_option!(statement.get_triplet_arg(1, *line_no)).into();
             let vertex_c = try_option!(statement.get_triplet_arg(2, *line_no)).into();
@@ -121,7 +176,7 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
                 material_name,
             }))
         })
-        .collect::<Result<Vec<Face>, _>>()?;
+        .collect::<Result<Vec<Face>, Error>>()?;
 
     let mtl_libs = statements
         .iter()
@@ -139,7 +194,7 @@ pub fn parse(obj_content: &str) -> Result<Obj, Error>
 
             Some(Ok(mtl_lib_paths))
         })
-        .collect::<Result<Vec<_>, _>>()?;
+        .collect::<Result<Vec<_>, Error>>()?;
 
     Ok(Obj {
         vertex_positions,
@@ -295,6 +350,24 @@ pub enum Error
 
     #[error("Face vertices without normals are not yet supported")]
     NoFaceVertexNormalNotSupported,
+
+    #[error(
+        "Unsupported number of arguments ({arg_count}) to {keyword} at line {line_no}"
+    )]
+    UnsupportedArgumentCount
+    {
+        keyword: String,
+        arg_count: usize,
+        line_no: usize,
+    },
+
+    #[error("Invalid number of arguments ({arg_count}) to {keyword} at line {line_no}")]
+    InvalidArgumentCount
+    {
+        keyword: String,
+        arg_count: usize,
+        line_no: usize,
+    },
 }
 
 keyword! {