Mark no_mangle functions as unsafe

Resolves #104
geiger-rs · Jan 14, 2021 · e0c4d9c · e0c4d9c
1 parent df45256
commit e0c4d9c
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Showing 3 changed files with 30 additions and 15 deletions.
diff --git a/geiger/src/find.rs b/geiger/src/find.rs
@@ -54,6 +54,11 @@ pub fn g() {
     }.as_bytes()).unwrap();
 }
 
+#[no_mangle]
+pub fn h() {
+    unimplemented!()
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -76,11 +81,11 @@ mod tests {
             counters: CounterBlock {
                 functions: Count {
                     safe: 2,
-                    unsafe_: 1
+                    unsafe_: 2
                 },
                 exprs: Count {
                     safe: 4,
-                    unsafe_: 3
+                    unsafe_: 4
                 },
                 item_impls: Count {
                     safe: 0,
@@ -104,11 +109,11 @@ mod tests {
                 counters: CounterBlock {
                     functions: Count {
                         safe: 1,
-                        unsafe_: 1
+                        unsafe_: 2
                     },
                     exprs: Count {
                         safe: 4,
-                        unsafe_: 2
+                        unsafe_: 3
                     },
                     item_impls: Count {
                         safe: 0,
@@ -156,11 +161,11 @@ mod tests {
                 counters: CounterBlock {
                     functions: Count {
                         safe: 2,
-                        unsafe_: 1
+                        unsafe_: 2
                     },
                     exprs: Count {
                         safe: 4,
-                        unsafe_: 3
+                        unsafe_: 4
                     },
                     item_impls: Count {
                         safe: 0,
@@ -184,11 +189,11 @@ mod tests {
                 counters: CounterBlock {
                     functions: Count {
                         safe: 1,
-                        unsafe_: 1
+                        unsafe_: 2
                     },
                     exprs: Count {
                         safe: 4,
-                        unsafe_: 2
+                        unsafe_: 3
                     },
                     item_impls: Count {
                         safe: 0,

diff --git a/geiger/src/geiger_syn_visitor.rs b/geiger/src/geiger_syn_visitor.rs
@@ -1,5 +1,5 @@
 use super::{
-    file_forbids_unsafe, is_test_fn, is_test_mod, IncludeTests, RsFileMetrics,
+    file_forbids_unsafe, is_test_fn, is_test_mod, has_unsafe_attributes, IncludeTests, RsFileMetrics,
 };
 
 use syn::{visit, Expr, ImplItemMethod, ItemFn, ItemImpl, ItemMod, ItemTrait};
@@ -50,13 +50,14 @@ impl<'ast> visit::Visit<'ast> for GeigerSynVisitor {
         if IncludeTests::No == self.include_tests && is_test_fn(item_fn) {
             return;
         }
-        if item_fn.sig.unsafety.is_some() {
+        let unsafe_fn = item_fn.sig.unsafety.is_some() || has_unsafe_attributes(item_fn);
+        if unsafe_fn {
             self.enter_unsafe_scope()
         }
         self.metrics
             .counters
             .functions
-            .count(item_fn.sig.unsafety.is_some());
+            .count(unsafe_fn);
         visit::visit_item_fn(self, item_fn);
         if item_fn.sig.unsafety.is_some() {
             self.exit_unsafe_scope()

diff --git a/geiger/src/lib.rs b/geiger/src/lib.rs
@@ -88,7 +88,16 @@ fn is_test_fn(item_fn: &ItemFn) -> bool {
         .attrs
         .iter()
         .flat_map(Attribute::parse_meta)
-        .any(|m| meta_is_word_test(&m))
+        .any(|m| meta_contains_ident(&m, "test"))
+}
+
+fn has_unsafe_attributes(item_fn: &ItemFn) -> bool {
+    use syn::Attribute;
+    item_fn
+        .attrs
+        .iter()
+        .flat_map(Attribute::parse_meta)
+        .any(|m| meta_contains_ident(&m, "no_mangle"))
 }
 
 /// Will return true for #[cfg(test)] decorated modules.
@@ -110,10 +119,10 @@ fn is_test_mod(i: &ItemMod) -> bool {
         })
 }
 
-fn meta_is_word_test(m: &syn::Meta) -> bool {
+fn meta_contains_ident(m: &syn::Meta, ident: &str) -> bool {
     use syn::Meta;
     match m {
-        Meta::Path(p) => p.is_ident("test"),
+        Meta::Path(p) => p.is_ident(ident),
         _ => false,
     }
 }
@@ -139,7 +148,7 @@ fn meta_list_is_cfg_test(meta_list: &syn::MetaList) -> bool {
         return false;
     }
     meta_list.nested.iter().any(|n| match n {
-        NestedMeta::Meta(meta) => meta_is_word_test(meta),
+        NestedMeta::Meta(meta) => meta_contains_ident(meta, "test"),
         _ => false,
     })
 }