Don't require file length greater than region_len

mbrubeck · mbrubeck · commit f7a9ebfe78b4 · 2024-03-14T18:36:38.000-07:00
Fixes #15.
diff --git a/src/fdo_magic/check.rs b/src/fdo_magic/check.rs
@@ -1,14 +1,16 @@
 use petgraph::prelude::*;
+use std::cmp::min;
 use std::iter::zip;
 
 fn from_u8_singlerule(bytes: &[u8], rule: &super::MagicRule) -> bool {
     // Check if we're even in bounds
     let bound_min = rule.start_off as usize;
-    let bound_max = rule.start_off as usize + rule.val.len() + rule.region_len as usize;
-
-    if bound_max > bytes.len() {
+    if bound_min > bytes.len() {
         return false;
     }
+    let bound_max = rule.start_off as usize + rule.val.len() + rule.region_len as usize;
+    let bound_max = min(bound_max, bytes.len());
+
     let testarea = &bytes[bound_min..bound_max];
 
     testarea.windows(rule.val.len()).any(|window| {
diff --git a/tests/from_u8.rs b/tests/from_u8.rs
@@ -83,6 +83,14 @@ mod from_u8 {
     }
 
     /// Text tests
+    #[test]
+    fn text_html() {
+        assert_eq!(
+            tree_magic::from_u8(include_bytes!("text/html")),
+            convmime!("text/html")
+        );
+    }
+
     #[test]
     fn text_plain() {
         assert_eq!(
diff --git a/tests/text/html b/tests/text/html
@@ -0,0 +1,7 @@
+<!DOCTYPE HTML>
+<html>
+  <head>
+    <title>Test</title>
+  </head>
+  <body></body>
+</html>
