Return an InvalidQuery error when SQL is not read only

src/error.rs

@@ -77,6 +77,9 @@ pub enum Error {
 
     /// Error available for the implementors of the `ToSql` trait.
     ToSqlConversionFailure(Box<error::Error + Send + Sync>),
+
+    /// Error when the SQL is not a `SELECT`, is not read-only.
+    InvalidQuery,
 }
 
 impl From<str::Utf8Error> for Error {
@@ -132,6 +135,7 @@ impl fmt::Display for Error {
             #[cfg(feature = "functions")]
             Error::UserFunctionError(ref err) => err.fmt(f),
             Error::ToSqlConversionFailure(ref err) => err.fmt(f),
+            Error::InvalidQuery => write!(f, "Query is not read-only"),
         }
     }
 }
@@ -160,6 +164,7 @@ impl error::Error for Error {
             #[cfg(feature = "functions")]
             Error::UserFunctionError(ref err) => err.description(),
             Error::ToSqlConversionFailure(ref err) => err.description(),
+            Error::InvalidQuery => "query is not read-only",
         }
     }
 
@@ -178,7 +183,8 @@ impl error::Error for Error {
             Error::InvalidColumnName(_) |
             Error::InvalidColumnType(_, _) |
             Error::InvalidPath(_) |
-            Error::StatementChangedRows(_) => None,
+            Error::StatementChangedRows(_) |
+            Error::InvalidQuery => None,
 
             #[cfg(feature = "functions")]
             Error::InvalidFunctionParameterType(_, _) => None,

src/raw_statement.rs

@@ -83,6 +83,11 @@ impl RawStatement {
         self.0 = ptr::null_mut();
         r
     }
+
+    #[cfg(feature = "bundled")]
+    pub fn readonly(&self) -> bool {
+        unsafe { ffi::sqlite3_stmt_readonly(self.0) != 0 }
+    }
 }
 
 impl Drop for RawStatement {

src/statement.rs

@@ -154,6 +154,7 @@ impl<'conn> Statement<'conn> {
     ///
     /// Will return `Err` if binding parameters fails.
     pub fn query<'a>(&'a mut self, params: &[&ToSql]) -> Result<Rows<'a>> {
+        try!(self.check_readonly());
         try!(self.bind_parameters(params));
         Ok(Rows::new(self))
     }
@@ -181,6 +182,7 @@ impl<'conn> Statement<'conn> {
     ///
     /// Will return `Err` if binding parameters fails.
     pub fn query_named<'a>(&'a mut self, params: &[(&str, &ToSql)]) -> Result<Rows<'a>> {
+        try!(self.check_readonly());
         try!(self.bind_parameters_named(params));
         Ok(Rows::new(self))
     }
@@ -465,6 +467,19 @@ impl<'conn> Statement<'conn> {
         mem::swap(&mut stmt, &mut self.stmt);
         self.conn.decode_result(stmt.finalize())
     }
+
+    #[cfg(not(feature = "bundled"))]
+    fn check_readonly(&self) -> Result<()> {
+        Ok(())
+    }
+
+    #[cfg(feature = "bundled")]
+    fn check_readonly(&self) -> Result<()> {
+        if !self.stmt.readonly() {
+            return Err(Error::InvalidQuery);
+        }
+        Ok(())
+    }
 }
 
 impl<'conn> Into<RawStatement> for Statement<'conn> {