[Rust] Metadata API improvements

- Don't use Result for some or none values
- Fix freeing of key value store objects
- Improve ergonomics a little bit
- Add unit tests

1 files changed, 88 insertions, 85 deletions

diff --git a/rust/src/metadata.rs b/rust/src/metadata.rs
index 6cf1cbce..e541577d 100644
--- a/rust/src/metadata.rs
+++ b/rust/src/metadata.rs
@@ -1,5 +1,5 @@
 use crate::rc::{Array, CoreArrayProvider, CoreArrayProviderInner, Guard, Ref, RefCountable};
-use crate::string::{BnString, IntoCStr, IntoJson};
+use crate::string::{raw_to_string, BnString, IntoCStr, IntoJson};
 use binaryninjacore_sys::*;
 use std::collections::HashMap;
 use std::os::raw::c_char;
@@ -30,129 +30,129 @@ impl Metadata {
         unsafe { BNMetadataGetType(self.handle) }
     }
 
-    pub fn get_boolean(&self) -> Result<bool, ()> {
+    pub fn get_boolean(&self) -> Option<bool> {
         match self.get_type() {
-            MetadataType::BooleanDataType => Ok(unsafe { BNMetadataGetBoolean(self.handle) }),
-            _ => Err(()),
+            MetadataType::BooleanDataType => Some(unsafe { BNMetadataGetBoolean(self.handle) }),
+            _ => None,
         }
     }
 
-    pub fn get_unsigned_integer(&self) -> Result<u64, ()> {
+    pub fn get_unsigned_integer(&self) -> Option<u64> {
         match self.get_type() {
             MetadataType::UnsignedIntegerDataType => {
-                Ok(unsafe { BNMetadataGetUnsignedInteger(self.handle) })
+                Some(unsafe { BNMetadataGetUnsignedInteger(self.handle) })
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_signed_integer(&self) -> Result<i64, ()> {
+    pub fn get_signed_integer(&self) -> Option<i64> {
         match self.get_type() {
             MetadataType::SignedIntegerDataType => {
-                Ok(unsafe { BNMetadataGetSignedInteger(self.handle) })
+                Some(unsafe { BNMetadataGetSignedInteger(self.handle) })
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_double(&self) -> Result<f64, ()> {
+    pub fn get_double(&self) -> Option<f64> {
         match self.get_type() {
-            MetadataType::DoubleDataType => Ok(unsafe { BNMetadataGetDouble(self.handle) }),
-            _ => Err(()),
+            MetadataType::DoubleDataType => Some(unsafe { BNMetadataGetDouble(self.handle) }),
+            _ => None,
         }
     }
 
-    pub fn get_string(&self) -> Result<BnString, ()> {
+    pub fn get_string(&self) -> Option<BnString> {
         match self.get_type() {
             MetadataType::StringDataType => {
                 let ptr: *mut c_char = unsafe { BNMetadataGetString(self.handle) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
-                Ok(unsafe { BnString::from_raw(ptr) })
+                Some(unsafe { BnString::from_raw(ptr) })
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_boolean_list(&self) -> Result<Vec<bool>, ()> {
+    pub fn get_boolean_list(&self) -> Option<Vec<bool>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut bool = unsafe { BNMetadataGetBooleanList(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = Vec::from(list);
                 unsafe { BNFreeMetadataBooleanList(ptr, size) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_unsigned_integer_list(&self) -> Result<Vec<u64>, ()> {
+    pub fn get_unsigned_integer_list(&self) -> Option<Vec<u64>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut u64 =
                     unsafe { BNMetadataGetUnsignedIntegerList(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = Vec::from(list);
                 unsafe { BNFreeMetadataUnsignedIntegerList(ptr, size) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_signed_integer_list(&self) -> Result<Vec<i64>, ()> {
+    pub fn get_signed_integer_list(&self) -> Option<Vec<i64>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut i64 =
                     unsafe { BNMetadataGetSignedIntegerList(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = Vec::from(list);
                 unsafe { BNFreeMetadataSignedIntegerList(ptr, size) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_double_list(&self) -> Result<Vec<f64>, ()> {
+    pub fn get_double_list(&self) -> Option<Vec<f64>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut f64 = unsafe { BNMetadataGetDoubleList(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = Vec::from(list);
                 unsafe { BNFreeMetadataDoubleList(ptr, size) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_string_list(&self) -> Result<Vec<BnString>, ()> {
+    pub fn get_string_list(&self) -> Option<Vec<BnString>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut *mut c_char =
                     unsafe { BNMetadataGetStringList(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = list
@@ -160,66 +160,66 @@ impl Metadata {
                     .map(|ptr| unsafe { BnString::from_raw(*ptr) })
                     .collect::<Vec<_>>();
                 unsafe { BNFreeMetadataStringList(ptr, size) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_json_string(&self) -> Result<BnString, ()> {
+    pub fn get_json_string(&self) -> Option<BnString> {
         match self.get_type() {
             MetadataType::StringDataType => {
                 let ptr: *mut c_char = unsafe { BNMetadataGetJsonString(self.handle) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
-                Ok(unsafe { BnString::from_raw(ptr) })
+                Some(unsafe { BnString::from_raw(ptr) })
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_raw(&self) -> Result<Vec<u8>, ()> {
+    pub fn get_raw(&self) -> Option<Vec<u8>> {
         match self.get_type() {
             MetadataType::RawDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut u8 = unsafe { BNMetadataGetRaw(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
 
                 let list = unsafe { slice::from_raw_parts(ptr, size) };
                 let vec = Vec::from(list);
                 unsafe { BNFreeMetadataRaw(ptr) };
-                Ok(vec)
+                Some(vec)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_array(&self) -> Result<Array<Metadata>, ()> {
+    pub fn get_array(&self) -> Option<Array<Metadata>> {
         match self.get_type() {
             MetadataType::ArrayDataType => {
                 let mut size: usize = 0;
                 let ptr: *mut *mut BNMetadata =
                     unsafe { BNMetadataGetArray(self.handle, &mut size) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
 
-                Ok(unsafe { Array::new(ptr, size, ()) })
+                Some(unsafe { Array::new(ptr, size, ()) })
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
-    pub fn get_value_store(&self) -> Result<HashMap<String, Ref<Metadata>>, ()> {
+    pub fn get_value_store(&self) -> Option<HashMap<String, Ref<Metadata>>> {
         match self.get_type() {
             MetadataType::KeyValueDataType => {
                 let ptr: *mut BNMetadataValueStore =
                     unsafe { BNMetadataGetValueStore(self.handle) };
                 if ptr.is_null() {
-                    return Err(());
+                    return None;
                 }
 
                 let size = unsafe { (*ptr).size };
@@ -230,21 +230,16 @@ impl Metadata {
 
                 let mut map = HashMap::new();
                 for i in 0..size {
-                    let key = unsafe { BnString::into_string(keys[i]) };
-
-                    let value = unsafe {
-                        Ref::<Metadata>::new(Self {
-                            handle: BNNewMetadataReference(values[i]),
-                        })
-                    };
+                    let key = raw_to_string(keys[i]).unwrap();
+                    let value = unsafe { Ref::<Metadata>::new(Self { handle: values[i] }) };
                     map.insert(key, value);
                 }
 
                 unsafe { BNFreeMetadataValueStore(ptr) };
 
-                Ok(map)
+                Some(map)
             }
-            _ => Err(()),
+            _ => None,
         }
     }
 
@@ -424,10 +419,12 @@ impl From<&Array<Metadata>> for Ref<Metadata> {
     }
 }
 
-impl<S: IntoCStr> From<HashMap<S, Ref<Metadata>>> for Ref<Metadata> {
-    fn from(value: HashMap<S, Ref<Metadata>>) -> Self {
-        let data: Vec<(S::Result, Ref<Metadata>)> =
-            value.into_iter().map(|(k, v)| (k.to_cstr(), v)).collect();
+impl<S: IntoCStr, T: Into<Ref<Metadata>>> From<HashMap<S, T>> for Ref<Metadata> {
+    fn from(value: HashMap<S, T>) -> Self {
+        let data: Vec<(S::Result, Ref<Metadata>)> = value
+            .into_iter()
+            .map(|(k, v)| (k.to_cstr(), v.into()))
+            .collect();
         let mut keys: Vec<*const c_char> = data.iter().map(|(k, _)| k.as_ptr()).collect();
         let mut values: Vec<*mut BNMetadata> = data.iter().map(|(_, v)| v.handle).collect();
 
@@ -549,7 +546,7 @@ impl TryFrom<&Metadata> for bool {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_boolean()
+        value.get_boolean().ok_or(())
     }
 }
 
@@ -557,7 +554,7 @@ impl TryFrom<&Metadata> for u64 {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_unsigned_integer()
+        value.get_unsigned_integer().ok_or(())
     }
 }
 
@@ -565,7 +562,7 @@ impl TryFrom<&Metadata> for i64 {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_signed_integer()
+        value.get_signed_integer().ok_or(())
     }
 }
 
@@ -573,7 +570,7 @@ impl TryFrom<&Metadata> for f64 {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_double()
+        value.get_double().ok_or(())
     }
 }
 
@@ -581,7 +578,7 @@ impl TryFrom<&Metadata> for BnString {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_string()
+        value.get_string().ok_or(())
     }
 }
 
@@ -589,7 +586,10 @@ impl TryFrom<&Metadata> for String {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_string().map(|s| s.to_string_lossy().to_string())
+        value
+            .get_string()
+            .map(|s| s.to_string_lossy().to_string())
+            .ok_or(())
     }
 }
 
@@ -597,7 +597,7 @@ impl TryFrom<&Metadata> for Vec<bool> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_boolean_list()
+        value.get_boolean_list().ok_or(())
     }
 }
 
@@ -605,7 +605,7 @@ impl TryFrom<&Metadata> for Vec<u64> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_unsigned_integer_list()
+        value.get_unsigned_integer_list().ok_or(())
     }
 }
 
@@ -613,7 +613,7 @@ impl TryFrom<&Metadata> for Vec<i64> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_signed_integer_list()
+        value.get_signed_integer_list().ok_or(())
     }
 }
 
@@ -621,7 +621,7 @@ impl TryFrom<&Metadata> for Vec<f64> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_double_list()
+        value.get_double_list().ok_or(())
     }
 }
 
@@ -629,7 +629,7 @@ impl TryFrom<&Metadata> for Vec<BnString> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_string_list()
+        value.get_string_list().ok_or(())
     }
 }
 
@@ -637,11 +637,14 @@ impl TryFrom<&Metadata> for Vec<String> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_string_list().map(|v| {
-            v.into_iter()
-                .map(|s| s.to_string_lossy().to_string())
-                .collect()
-        })
+        value
+            .get_string_list()
+            .map(|v| {
+                v.into_iter()
+                    .map(|s| s.to_string_lossy().to_string())
+                    .collect()
+            })
+            .ok_or(())
     }
 }
 
@@ -649,7 +652,7 @@ impl TryFrom<&Metadata> for Vec<u8> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_raw()
+        value.get_raw().ok_or(())
     }
 }
 
@@ -657,7 +660,7 @@ impl TryFrom<&Metadata> for Array<Metadata> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_array()
+        value.get_array().ok_or(())
     }
 }
 
@@ -665,20 +668,20 @@ impl TryFrom<&Metadata> for HashMap<String, Ref<Metadata>> {
     type Error = ();
 
     fn try_from(value: &Metadata) -> Result<Self, Self::Error> {
-        value.get_value_store()
+        value.get_value_store().ok_or(())
     }
 }
 
 impl IntoJson for &Metadata {
     type Output = BnString;
     fn get_json_string(self) -> Result<BnString, ()> {
-        Metadata::get_json_string(self)
+        Metadata::get_json_string(self).ok_or(())
     }
 }
 
 impl IntoJson for Ref<Metadata> {
     type Output = BnString;
     fn get_json_string(self) -> Result<BnString, ()> {
-        Metadata::get_json_string(&self)
+        Metadata::get_json_string(&self).ok_or(())
     }
 }