fix(*): attempt to fix various memory leaks (#16)

bridge/odict-bridging-lib.go

@@ -1,11 +1,13 @@
 package main
 
 // #define CGO_EXPORT_BRIDGE_EXISTS
+// #include <stdlib.h>
 import "C"
 
 import (
 	"encoding/base64"
 	"encoding/json"
+	"unsafe"
 
 	odict "github.com/odict/odict/go"
 )
@@ -54,6 +56,11 @@ func SearchDictionary(query, dict *C.char) *C.char {
 	return C.CString(string(b))
 }
 
+//export Free
+func Free(res *C.char) {
+	C.free(unsafe.Pointer(res))
+}
+
 //export IndexDictionary
 func IndexDictionary(dict *C.char) {
 	d := getDictionaryFromBuffer(dict)

java/main/cpp/odict.cpp

@@ -14,22 +14,37 @@ Java_org_odict_Dictionary_lookup(JNIEnv *env, jobject, jstring query, jstring di
 {
   const char *dictionary = env->GetStringUTFChars(dict, 0);
   const char *entry_term = env->GetStringUTFChars(query, 0);
-  return env->NewStringUTF(LookupEntry((char *)entry_term, (char *)dictionary));
+  char *result = LookupEntry((char *)entry_term, (char *)dictionary);
+  jstring str = env->NewStringUTF(result);
+
+  free(result);
+
+  return str;
 }
 
 extern "C" JNIEXPORT void JNICALL
 Java_org_odict_Dictionary_index(JNIEnv *env, jobject, jstring encoded)
 {
-  IndexDictionary((char *)env->GetStringUTFChars(encoded, 0));
+  char *enc = (char *)env->GetStringUTFChars(encoded, 0);
+  IndexDictionary(enc);
+  env->ReleaseStringUTFChars(encoded, enc);
 }
 
 extern "C" JNIEXPORT jstring JNICALL
 Java_org_odict_Dictionary_search(JNIEnv *env, jobject, jstring query, jstring encoded)
 {
-  const char *q = env->GetStringUTFChars(query, 0);
-  const char *result = SearchDictionary((char *)q, (char *)env->GetStringUTFChars(encoded, 0));
+  char *q = (char *)env->GetStringUTFChars(query, 0);
+  char *enc = (char *)env->GetStringUTFChars(encoded, 0);
+  const char *result = SearchDictionary(q, enc);
+
+  jstring res = env->NewStringUTF(result);
 
-  return env->NewStringUTF(result);
+  env->ReleaseStringUTFChars(query, q);
+  env->ReleaseStringUTFChars(encoded, enc);
+
+  free((char *)result);
+
+  return res;
 }
 
 extern "C" JNIEXPORT jstring JNICALL
@@ -38,20 +53,33 @@ Java_org_odict_Dictionary_read(JNIEnv *env, jobject, jstring path)
   const char *dictionary_path = env->GetStringUTFChars(path, 0);
   char *encoded = ReadDictionary((char *)dictionary_path);
 
-  return env->NewStringUTF(encoded);
+  jstring res = env->NewStringUTF(encoded);
+
+  env->ReleaseStringUTFChars(path, dictionary_path);
+
+  free(encoded);
+
+  return res;
 }
 
 extern "C" JNIEXPORT void JNICALL
 Java_org_odict_Dictionary_write(JNIEnv *env, jobject, jstring xml, jstring path)
 {
   const char *dictionary_path = env->GetStringUTFChars(path, 0);
   const char *content = env->GetStringUTFChars(xml, 0);
+
   WriteDictionary((char *)content, (char *)dictionary_path);
+
+  env->ReleaseStringUTFChars(path, dictionary_path);
+  env->ReleaseStringUTFChars(xml, content);
 }
 
 extern "C" JNIEXPORT void JNICALL
 Java_org_odict_Dictionary_compile(JNIEnv *env, jobject, jstring path)
 {
   const char *dictionary_path = env->GetStringUTFChars(path, 0);
+
   CompileDictionary((char *)dictionary_path);
+
+  env->ReleaseStringUTFChars(path, dictionary_path);
 }

java/test/java/org/odict/TestDictionary.java

@@ -16,7 +16,7 @@ public void testLookup() throws Exception {
     String json = dict.lookup("run");
     String expected = "{\"term\":\"run\",\"etymologies\":[{\"id\":\"0\",\"usages\":{\"n\":{\"pos\":\"n\",\"definitions\":[\"Act or instance of running, of moving rapidly using the feet.\",\"Act or instance of hurrying (to or from a place) (not necessarily by foot); dash or errand, trip.\",\"A pleasure trip.\",\"Flight, instance or period of fleeing.\",\"Migration (of fish).\",\"A group of fish that migrate, or ascend a river for the purpose of spawning.\"]},\"v\":{\"pos\":\"v\",\"groups\":[{\"id\":\"\",\"description\":\"A number of verb usages\",\"definitions\":[\"(vertebrates) To move swiftly.\",\"(fluids) To flow.\",\"(nautical, of a vessel) To sail before the wind, in distinction from reaching or sailing close-hauled.\",\"(social) To carry out an activity.\",\"To extend or persist, statically or dynamically, through space or time.\",\"(transitive) To execute or carry out a plan, procedure or program.\"]}]}}}]}";
 
-    assertEquals(json, expected);
+    assertEquals(expected, json);
   }
 
   @Test
@@ -41,7 +41,8 @@ public void testWrite() throws Exception {
     Dictionary dict = new Dictionary("test.odict");
     String json = dict.lookup("hello");
 
-    assertEquals(json,
-        "{\"term\":\"hello\",\"etymologies\":[{\"id\":\"0\",\"usages\":{\"v\":{\"pos\":\"v\",\"definitions\":[\"hello world\"]}}}]}");
+    assertEquals(
+        "{\"term\":\"hello\",\"etymologies\":[{\"id\":\"0\",\"usages\":{\"v\":{\"pos\":\"v\",\"definitions\":[\"hello world\"]}}}]}",
+        json);
   }
 }

python/odict.py

@@ -28,37 +28,59 @@ def __find_library():
 
 lib = cdll.LoadLibrary(__find_library())
 
-lib.SearchDictionary.restype = c_char_p
-lib.LookupEntry.restype = c_char_p
-lib.ReadDictionary.restype = c_char_p
+lib.SearchDictionary.restype = c_void_p
+lib.LookupEntry.restype = c_void_p
+lib.ReadDictionary.restype = c_void_p
+lib.Free.argtypes = [c_void_p]
+lib.Free.restype = None
 
 
 class Dictionary:
 
     def __init__(self, path, should_index=False):
-        self.__encoded_dict = lib.ReadDictionary(path.encode('utf-8'))
-        print("hello")
-        print(self.__encoded_dict)
+        p = path.encode('utf-8')
+        self.__encoded_dict = lib.ReadDictionary(p)
+
         if should_index:
             self.index()
 
+    def __del__(self):
+        lib.Free(self.__encoded_dict)
+
     @staticmethod
     def compile(path):
-        lib.CompileDictionary(path.encode('utf-8'))
+        p = path.encode('utf-8')
+        lib.CompileDictionary(p)
 
     @staticmethod
     def write(xml, path):
-        lib.WriteDictionary(xml.encode('utf-8'), path.encode('utf-8'))
+        try:
+            lib.WriteDictionary(xml.encode('utf-8'), path.encode('utf-8'))
+        except:
+            print("An exception occurred")
+
+    def __get_dictionary(self):
+        return cast(self.__encoded_dict, c_char_p).value
 
     def search(self, query):
-        return self.__decode(lib.SearchDictionary(self.__encode(query), self.__encoded_dict))
+        v = lib.SearchDictionary(self.__encode(query), self.__get_dictionary())
+        d = self.__decode(cast(v, c_char_p).value)
+
+        lib.Free(v)
+
+        return d
 
     def index(self):
-        lib.IndexDictionary(self.__encoded_dict)
+        lib.IndexDictionary(self.__get_dictionary())
 
     def lookup(self, term):
-        print(self.__encoded_dict)
-        return self.__decode(lib.LookupEntry(self.__encode(term), self.__encoded_dict))
+        e = self.__encode(term)
+        v = lib.LookupEntry(e, self.__get_dictionary())
+        d = self.__decode(cast(v, c_char_p).value)
+
+        lib.Free(v)
+
+        return d
 
     def __encode(self, str):
         return str.encode('utf-8')