[swig]: Fix swig template memory leak on issue 17025

.azure-pipelines/build-template.yml

@@ -110,7 +110,7 @@ jobs:
       displayName: "Install gcovr 5.2 (for --exclude-throw-branches support)"
     - script: |
         set -ex
-        sudo pip install Pympler==0.8
+        sudo pip install Pympler==0.8 pytest psutil
         sudo apt-get install -y redis-server
         sudo sed -i 's/notify-keyspace-events ""/notify-keyspace-events AKE/' /etc/redis/redis.conf
         sudo sed -ri 's/^# unixsocket/unixsocket/' /etc/redis/redis.conf

common/table.cpp

@@ -82,7 +82,7 @@ bool Table::get(const string &key, vector<FieldValueTuple> &values)
     for (unsigned int i = 0; i < reply->elements; i += 2)
     {
         values.emplace_back(stripSpecialSym(reply->element[i]->str),
-                                    reply->element[i + 1]->str);
+                                    string(reply->element[i + 1]->str, reply->element[i + 1]->len));
     }
 
     return true;

pyext/swsscommon.i

@@ -53,6 +53,8 @@
 #include "zmqclient.h"
 #include "zmqconsumerstatetable.h"
 #include "zmqproducerstatetable.h"
+#include <memory>
+#include <functional>
 %}
 
 %include <std_string.i>
@@ -152,31 +154,36 @@
     SWIG_Python_AppendOutput($result, temp);
 }
 
-%typemap(in, fragment="SWIG_AsPtr_std_string")
+%typemap(in, fragment="SWIG_AsVal_std_string")
     const std::vector<std::pair< std::string,std::string >,std::allocator< std::pair< std::string,std::string > > > &
         (std::vector< std::pair< std::string,std::string >,std::allocator< std::pair< std::string,std::string > > > temp,
         int res) {
     res = SWIG_OK;
     for (int i = 0; i < PySequence_Length($input); ++i) {
         temp.push_back(std::pair< std::string,std::string >());
-        PyObject *item = PySequence_GetItem($input, i);
-        if (!PyTuple_Check(item) || PyTuple_Size(item) != 2) {
+        std::unique_ptr<PyObject, std::function<void(PyObject *)> > item(
+            PySequence_GetItem($input, i), 
+            [](PyObject *ptr){
+                Py_DECREF(ptr);
+            });
+        if (!PyTuple_Check(item.get()) || PyTuple_Size(item.get()) != 2) {
             SWIG_fail;
         }
-        PyObject *key = PyTuple_GetItem(item, 0);
-        PyObject *value = PyTuple_GetItem(item, 1);
-        std::string *ptr = (std::string *)0;
+        PyObject *key = PyTuple_GetItem(item.get(), 0);
+        PyObject *value = PyTuple_GetItem(item.get(), 1);
+        std::string str;
+
         if (PyBytes_Check(key)) {
             temp.back().first.assign(PyBytes_AsString(key), PyBytes_Size(key));
-        } else if (SWIG_AsPtr_std_string(key, &ptr)) {
-            temp.back().first = *ptr;
+        } else if (SWIG_AsVal_std_string(key, &str) != SWIG_ERROR) {
+            temp.back().first = str;
         } else {
             SWIG_fail;
         }
         if (PyBytes_Check(value)) {
             temp.back().second.assign(PyBytes_AsString(value), PyBytes_Size(value));
-        } else if (SWIG_AsPtr_std_string(value, &ptr)) {
-            temp.back().second = *ptr;
+        } else if (SWIG_AsVal_std_string(value, &str) != SWIG_ERROR) {
+            temp.back().second = str;
         } else {
             SWIG_fail;
         }
@@ -187,13 +194,17 @@
 %typemap(typecheck) const std::vector< std::pair< std::string,std::string >,std::allocator< std::pair< std::string,std::string > > > &{
     $1 = 1;
     for (int i = 0; i < PySequence_Length($input); ++i) {
-        PyObject *item = PySequence_GetItem($input, i);
-        if (!PyTuple_Check(item) || PyTuple_Size(item) != 2) {
+        std::unique_ptr<PyObject, std::function<void(PyObject *)> > item(
+            PySequence_GetItem($input, i), 
+            [](PyObject *ptr){
+                Py_DECREF(ptr);
+            });
+        if (!PyTuple_Check(item.get()) || PyTuple_Size(item.get()) != 2) {
             $1 = 0;
             break;
         }
-        PyObject *key = PyTuple_GetItem(item, 0);
-        PyObject *value = PyTuple_GetItem(item, 1);
+        PyObject *key = PyTuple_GetItem(item.get(), 0);
+        PyObject *value = PyTuple_GetItem(item.get(), 1);
         if (!PyBytes_Check(key)
             && !PyUnicode_Check(key)
             && !PyString_Check(key)

tests/redis_ut.cpp

@@ -16,6 +16,7 @@
 #include "common/table.h"
 #include "common/dbinterface.h"
 #include "common/sonicv2connector.h"
+#include "common/redisutility.h"
 
 using namespace std;
 using namespace swss;
@@ -845,6 +846,34 @@ TEST(Table, ttl_test)
     cout << "Done." << endl;
 }
 
+TEST(Table, binary_data_get)
+{
+    DBConnector db("TEST_DB", 0, true);
+    Table table(&db, "binary_data");
+
+    const char* bindata1 = "\x11\x00\x22\x33\x44";
+    const char* bindata2 = "\x11\x22\x33\x00\x44";
+    auto v1 = std::string(bindata1, sizeof(bindata1));
+    auto v2 = std::string(bindata2, sizeof(bindata2));
+    vector<FieldValueTuple> values_set = {
+        {"f1", v1},
+        {"f2", v2},
+    };
+
+    table.set("k1", values_set);
+
+    vector<FieldValueTuple> values_get;
+    EXPECT_TRUE(table.get("k1", values_get));
+
+    auto f1 = swss::fvsGetValue(values_get, "f1");
+    auto f2 = swss::fvsGetValue(values_get, "f2");
+    EXPECT_TRUE(f1);
+    EXPECT_TRUE(f2);
+
+    EXPECT_EQ(*f1, v1);
+    EXPECT_EQ(*f2, v2);
+}
+
 TEST(ProducerConsumer, Prefix)
 {
     std::string tableName = "tableName";

tests/test_redis_ut.py

@@ -1,5 +1,6 @@
 import os
 import time
+import psutil
 import pytest
 import multiprocessing
 from threading import Thread
@@ -801,4 +802,32 @@ def test_ConfigDBConnector():
     allconfig["PORT_TABLE"] = None
     config_db.mod_config(allconfig)
     allconfig = config_db.get_config()
-    assert len(allconfig) == 0
+    assert len(allconfig) == 0
+
+
+def test_TableSetBinary():
+    app_db = swsscommon.DBConnector("APPL_DB", 0, True)
+    t = swsscommon.Table(app_db, "TABLE")
+    buff = b""
+    for i in range(0, 256):
+        buff += bytes([i])
+    buff = buff.decode('latin-1')
+    fvs = swsscommon.FieldValuePairs([("binary", buff)])
+    t.set("binary", fvs)
+    (status, fvs) = t.get("binary")
+    assert status == True
+    assert fvs[0][1] == buff
+
+
+def test_TableOpsMemoryLeak():
+    OP_COUNT = 50000
+    app_db = swsscommon.DBConnector("APPL_DB", 0, True)
+    t = swsscommon.Table(app_db, "TABLE")
+    long_data = "x" * 100
+    fvs = swsscommon.FieldValuePairs([(long_data, long_data)])
+    rss = psutil.Process(os.getpid()).memory_info().rss
+    for _ in range(OP_COUNT):
+        t.set("long_data", fvs)
+        t.get("long_data")
+    assert psutil.Process(os.getpid()).memory_info().rss - rss < OP_COUNT
+